Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective [1 ed.] 9781619424661, 9781619424203

Citation preview

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science Publishers,

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

SPORTS AND ATHLETICS PREPARATION, PERFORMANCE, AND PSYCHOLOGY

PACING IN SPORT AND EXERCISE:

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

A PSYCHOPHYSIOLOGICAL PERSPECTIVE No part of this digital document may be reproduced, stored in a retrieval system or transmitted in any form or by any means. The publisher has taken reasonable care in the preparation of this digital document, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained herein. This digital document is sold with the clear understanding that the publisher is not engaged in rendering legal, medical or any other professional services.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

SPORTS AND ATHLETICS PREPARATION, PERFORMANCE, AND PSYCHOLOGY Additional books in this series can be found on Nova’s website under the Series tab.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Additional E-books in this series can be found on Nova’s website under the E-book tab.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

SPORTS AND ATHLETICS PREPARATION, PERFORMANCE, AND PSYCHOLOGY

PACING IN SPORT AND EXERCISE: A PSYCHOPHYSIOLOGICAL PERSPECTIVE

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

ANDREW EDWARDS AND

REMCO POLMAN

Nova Science Publishers, Inc. New York

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012 by Nova Science Publishers, Inc. All rights reserved. No part of this book may b e r eproduced, stored in a r etrieval system or transmitted in a ny form or b y any means: e lectronic, e lectrostatic, magnetic, tap e, m echanical photocopying, recording or otherwise without the written permission of the Publisher. For permission to use material from this book please contact us: Telephone 631-231-7269; Fax 631-231-8175 Web Site: http://www.novapublishers.com NOTICE TO THE READER The Publisher has taken reasonable care in the prep aration of this bo ok, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is as sumed for incidental or consequential damages in conn ection with or arising out of information conta ined in this boo k. The P ublisher sha ll not be liable for any s pecial, consequential, or exemplary damages resulting, in whole or in par t, from the readers’ use of , or reliance upon, this material. Any parts of this book based on government reports are so indicated and copyright is claimed for those parts to the extent applicable to compilations of such works.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Independent verification should be sought for any data, advice or recommendations contained in this book. In addition, no responsibility is assumed by the publisher for any injury and/or damage to pers ons or pr operty arising from an y methods, product s, in structions, idea s or otherwise contained in this publication. This publication is designed to provide accurate and authoritative information with re gard to the subject m atter co vered herein. It is sold with the cl ear unde rstanding that the Publisher is not engaged in rend ering lega l or a ny other pro fessional service s. If legal or an y othe r e xpert assistance is req uired, the services of a competent person s hould be so ught. F ROM A DECLARATION OF PARTICIPANTS JOINTLY AD OPTED B Y A COMMITTEE OF THE AMERICAN BAR ASSOCIATION AND A COMMITTEE OF PUBLISHERS. Additional color graphics may be available in the e-book version of this book. LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA Pacing in sport and exercise : a psychophysiological perspective / Andrew Edwards and Remco Polman , editors. p. cm. Includes index. ISBN 978-1-61942-466-1 (E-Book) 1. Sports--Psychological aspects. 2. Sports--Physiological aspects. 3. Cardiac pacing. 4. Endurance sports. I. Edwards, Andrew. II. Polman, Remco. GV706.4.P335 2011 796.01--dc23 2011047268

Published by Nova Science Publishers, Inc. † New York

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

For all my friends and family who have supported me over the years. In particular this is for my wife Tracy, son Alex and father Harry Edwards. Andrew To my mother for all her love and support throughout my life.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Remco 

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

CONTENTS List of Figures

vii 

List of Tables

xi 

Foreword

xv 

Preface

xvii 

Acknowledgments

xxi 

Author Biographies

xxiii 

Chapter 1

Evolution of Training and Performance 1.1. Abstract 1.2. Introduction 1.3. Evolution of Human Athletic Performance 1.4. Evolution of Training Methods 1.5. The Challenge of Sustaining Progress Conclusion References

1  1  1  2  6  15  18  19 

Chapter 2

An Introduction to Pacing in Sport and Exercise 2.1. Abstract 2.2. Introduction 2.3. The Concept of Pacing 2.4. The Origins of Paced Activity 2.5. Psychology of Pacing 2.6. Performance and Pacing Strategy Conclusion References

23  23  23  24  27  31  34  41  42 

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

iv

Contents

Chapter 3

Limitations to Physical Performance 3.1. Abstract 3.2. Introduction 3.3. The Nervous System 3.4. Limitations: Central and Peripheral Observations 3.5. Limitations: Cardiovascular Regulation 3.6. Limitations: Brain Regulation 3.7. Limitations: Psychological Considerations Conclusion References

49  49  49  50  53  55  58  65  69  70 

Chapter 4

Monitoring and Self-Regulating Training 4.1. Abstract 4.2. Introduction 4.3. Methods to Monitor Training Outcomes 4.4. Self-Regulatory Training Skills Conclusion References

77  77  77  78  87  95  95 

Chapter 5

Pacing for Endurance 5.1. Abstract 5.2. Introduction 5.3. Physiology of Endurance 5.4. Psychology of Endurance 5.5. Pacing and Strategy for Endurance 5.6. Self-Regulatory Training for Endurance 5.7. Athlete Comment: Endurance Conclusion References

99  99  99  100  105  109  114  123  124  125 

Chapter 6

Pacing for Power, Strength and Speed 6.1. Abstract 6.2. Introduction 6.3. Physiology of Anaerobic Exercise (Power, Strength and Speed) 6.4. Psychological Aspects of Pacing for Power, Strength and Speed 6.5. Pacing for Power, Strength and Speed 6.6. Self-Paced Anaerobic Training 6.7. Athlete Comment: Power, Strength, Speed

131  131  131 

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

132  134  136  140  150 

Contents

v

Conclusion References

150  151 

Chapter 7

Pacing for Team Sports 7.1. Abstract 7.2. Introduction 7.3. Match Demands 7.4. Pacing for Team Sports 7.5. Preparatory Psychological Skills for Team Sports 7.6. Training for Team Sports 7.7. Practitioner Comment: Team Sports Conclusion References

157  157  157  158  160  165  167  177  178  178 

Chapter 8

Pacing for Special Populations 8.1. Abstract 8.2. Introduction 8.3. Children and Pacing Conclusion References

183  183  183  184  194  195 

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Index

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

201 

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

LIST OF FIGURES Figure 1.1a (male) and 1.1b (female). Progression of male and female world record performances across selected track and field events .......... 3 Figure 1.2. Evolution of training periodization from the Greek tetrad to modern periodization...................................................... 9

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 1.3. Principles of overload whereby performance in response to each cyclic period of training (mesocycle) results in fatigue and subsequent adaptation and progressive performance gain .............. 13 Figure 1.4. An example of outcomes for training volume and intensity in response to nonlinear periodization resistance training. .................... 14 Figure 2.1a and 2.1b. The agony (800m) and ecstasy (1500m) of Sebastian (Lord) Coe vs. Steve Ovett at the 1980 Olympic games ....... 24 Figure 2.2. Humans and Cheetahs: both exhibit pacing behaviours in response to the known demands of a task ....................... 30 Figure 2.3. Average lap times (s) for 32 world record mile performances between 1880 and 1999. ................................................. 37 Figure 2.4. Six commonly observed pacing strategies. .................................. 39 Figure 3.1. Brain regulation of human movement in response to afferent and efferent signals................................................................... 50 Figure 3.2. Mechanism of fatigue according to AV Hill’s (Cardiovascular/Anaerobic) Model of Exercise Physiology ................. 56

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

viii

Andrew Edwards and Remco Polman

Figure 3.3. Example of oxygen uptake ( V⋅ O2) responses to two maximal incremental exercise challenges. ............................................ 59 Figure 3.4. Brain regulation of performance based on feedback (afferent) signals from different physiological systems and feedforward (efferent) signals to muscle ............................................... 61 Figure 3.5. A comparison of brain regulation models of human movement.................................................................. 64 Figure 3.6. Negative sensations such as metabolic acidosis develop in severity as exercise becomes progressively challenging ....................... 68 Figure 4.1. the CR10 Borg Rating of Perceived Exertion scale ..................... 85 Figure 4.2. An RPE-based system for monitoring responses and performance outcomes from a training programme .............................. 86 Figure 5.1. Summary of the main pathways of energy metabolism using carbohydrate and lipids as energy sources ................................. 101

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 5.2. Average speeds (m/s) (± SD) for swimming stage of the Lausanne 2002 ITU World Cup triathlons (n=68 males) ..................... 112 Figure 5.3. Speed (average±S.E. (km/h) over each bike lap of ITU male Triathlon by pack number to which the athletes belonged (5 packs) ... 112 Figure 5.4. Run speed (±S.E) for three packs of ITU World Cup male triathlon competitors. .................................................................. 113 Figure 5.5. Race pace profiles comparing on-water (n = 948) and ergometry (n = 170) trials. ............................................................ 114 Figure 6.1. Pacing of 1000m sprint performance in speed skating in experienced men and women .............................................................. 137 Figure 6.2. Power output in response to 30s Wingate testing, either with or without motivational music. .................................................... 139 Figure 6.3. Rating of perceived exertion (RPE) values at 50, 70, and 90% of 1 repetition maximum. ............................................................ 141 Figure 6.4. One repetition maximum (1RM) strength across leg press and chest press exercise both with and without a personal trainer being present .............................................................. 143

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

List of Figures

ix

Figure 7.1. Multi level model of pacing in team sports ................................ 162

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 7.2. An example of soccer match-play pacing strategy in operation with permission [3]. ........................................... 164

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

LIST OF TABLES Table 1.1. Progression of selected world track and field records from 1900 to 2011 .................................................................................... 4

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Table 4.1. A comparison of heart rate TRIMP outcomes for three training sessions and their accumulated score as an indicator of cyclic training load ............................................................................. 81 Table 4.2. Heart rate zone TRIMP [3]. This system allocates average heart rates into zones for subsequence TRIMP calculation (duration x zone) ..................................................................................... 82 Table 4.3. Summary of selected self-regulatory training skills. Many of these skills inter-relate ........................................................................ 94 Table 5.1. Preliminary profiling of interval (Int) training sessions for endurance athletes (duration x RPE) ............................................... 118 Table 5.2. Preliminary profiling of all continuous-run session options. ........ 119 Table 5.3. Preliminary profiling of all resistance training sessions ............... 119 Table 5.4. The example of a training schedule drawing on sessions identified from Tables 1-3 by the coach for implementation (endurance) ................................................................. 121 Table 5.5. Benchmarked descriptors and evaluation of training load (endurance).................................................................. 122 Table 5.6. Athlete’s weekly self evaluation and coping self assessments in relation to training load (endurance) ..................................................... 122

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

xii

Andrew Edwards and Remco Polman

Table 6.1. Preliminary profiling of interval training sessions (power, strength, speed) ........................................................................ 146 Table 6.2. Preliminary profiling of continuous-run sessions (power, strength, speed) ........................................................................ 147 Table 6.3. Preliminary profiling of resistance training sessions (power, strength, speed) ........................................................................ 147 Table 6.4. The training schedule and system for monitoring training load (power, strength, speed) ................................................................ 148 Table 6.5. Benchmarked descriptors and evaluation of training load (power, strength, speed) ........................................................................ 149 Table 6.6. Weekly training load (taken from table 4) and description, coupled with the athlete’s self assessment of coping (power, strength, speed) ..................................................................................... 149 Table 7.1. A summary of characteristics within the multi-level pacing model in elite team sport activities............................................ 162

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Table 7.2. Preliminary profiling of interval training (Int) sessions (team sports) ........................................................................... 172 Table 7.3. Preliminary profiling of small-sided games (SSG) (team sports) ...................................................... 173 Table 7.4. Preliminary profiling of skill-based training (SBT) (team sports) ......................................................................................... 173 Table 7.5. Preliminary profiling of continuous-run sessions (CON) (team sports) ......................................................................................... 174 Table 7.6. Preliminary profiling of strength and conditioning (SCT) (team sports) ........................................................................................ 174 Table 7.7. Match-play situations .................................................................... 175 Table 7.8.The training schedule and system for monitoring training load during the pre-season period of training (8 week programme) (team sports). ........................................................................................ 175 Table 7.9. Benchmarked descriptors and evaluation of training load (team sports). ................................................................... 176

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

List of Tables

xiii

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Table 7.10. Weekly training load and description, coupled with the athlete’s self assessment of coping (team sports) ................................. 176

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

FOREWORD Pacing is o ne of th e most important concep ts in s port and exercise. The regulation of ef fort is a choi ce that e very athlete a nd exerciser must ma ke continuously (if not alway s with awareness) throu ghout every worko ut and competition, and this choice has a profo und effect on o utcomes. The difference between successful and unsuccessful pacing is often the difference between achieving and falling short of goals; between benefiting and failing to benefit from the work that is done. Athletes, coaches, exercisers, a nd trainers hav e long reco gnized the importance of pacing and employed experience-based strategies and methods to t each and practice su ccessful pacin g. But un til recently pa cing received relatively little attention from exercise scientists. There was a tendency to view pacing as a psychological phen omenon an d th erefore outside the p urview of mainstream e xercise scie nce, whos e focus has always been phy siological. Inasmuch as pac ing was studied, i t was st udied fro m a physiological perspective t hat t ended to “ explain away” the obvious p sychological dimension of the phenomenon. Recent advances in ou r kn owledge of the b rain have lately b rought long overdue at tention t o pacing i n th e exercise science community. There is a growing recognition that pacing is a phenomenon with both psychological and physiological dimensi ons that are deeply mutually interpen etrating. Improvements in o ur understan ding of how the exercis e p acing mechanism really w orks a re opening up e xciting new pos sibilities for the pra ctice of effective pa cing in sport a nd exer cise. A need has therefore e merged for a comprehensive and authoritative resource that summarizes what we now know about exercise pa cing an d more f ully realizes th e pote ntial for practical

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

xvi

Andrew Edwards and Remco Polman

application of this new knowledge for a broad audience of scientists, coaches, trainers, athletes, and exercisers. Andrew Edwards and Remco Polman have met that need masterfully with this book. Pacing in Sport & Exercise pr esents a coge nt and compelling explanation of p acing that, while certainly not repres enting t he last word o n the su bject, is as cl ose as a nyone has y et come . O n t he soli d f oundation of their persuasive model the authors have constructed a perception-based system of monitor ing and controlling pace, as wel l as of quantifying and controlling training loads that is easy to compr ehend and apply, whether you’re a football coach or a beginning jogger seeking weight-loss. The bias toward phy siology an d technology t hat has dom inated sport training and e xercise pr escription f or many decades has disc ouraged pe ople from developing the refin ed sense of effort percep tion, the trust in such perception, and particular psychological tools without which optimal pacing is not p ossible. Pacing in Sport & Exercise holds the promise to cor rect th is imbalance with a single stroke, and I expect it to have a revolutionary effect in a wide range of sports and exercise modalities. For me per sonally, Edward s and Po lman’s book fills a big ho le that was left open i n my own efforts to help en durance athletes conceptually tie min d and body t ogether an d b ecome better p acers, hence bet ter racers—most notably i n my book s Brain Training for Runners and RUN: The Mind-Body Method of Running by Feel. I intend to rely heavily on Edwards and Polman’s invaluable new contribution to th e fi eld in m y future work as a w riter and coach, and I know I will not be alone. Matt Fitzgerald San Diego, California, USA

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

PREFACE The study of pacing is a r elatively new and exciting area of investigation, owing much to original studies by leading academics such as Professors Carl Foster, Ver onique Bi llat and T im N oakes. The se r esearchers, among ot hers, have demonstrated th at p acing is no t simply a muscle-driven outcome of performance; it is an i mportant regulatory proce ss that det ermines performance. Yet, the co ncept of pacing is not me rely confi ned to elite performance; it underlies all hu man m ovements in which vo luntary effort i s required. As s uch, t he mechanisms by whic h w e r egulate pace are complex, requiring mind-body in teraction. Th erefore, we have cons idered this top ic from a psychophysiological perspective. Pacing in Sport and Exercise: A Psychophysiological Perspective is , to our knowledge, the first book wh ich co mprehensively examines the way humans pace ex ercise and spor ting a ctivities. Rese arch on p acing has be en dominated b y p hysiological investigations despite the ackn owledgement by many authors on the interdisciplinary nature of pacing. Therefore, we consider both physiological and psychological influences on paci ng, before developing an interdisciplinary per spective. T his a pproach explains metabolic r egulation during e xercise and also f acilitates th e development of a practical ( selfregulatory) means with which to optimise training. Chapter on e of t his book provides a n o verview of the f actors as sociated with the evo lutionary development of human athletic performance. It presents a historical view on human training and conditioning perspectives and also on methods including the us e of linear and non-linear per iodization sy stems. Chapter two introduces the concept of pacing in sport and exercise. We define pacing as ‘the goal directed distribution and management of effort across the duration of an exercise bout’. Evidence from both animal and human studies is

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

xviii

Andrew Edwards and Remco Polman

presented to illustrate th e wa y species ad apt b ehaviour to contextual and personal constraints and pace activities accordingly. A guiding principle is to see pa cing as a ne ural buf fering pr ocess preventing premature physical exhaustion. In chapter three, both physical and psychological limitations to human performance are dis cussed. Limitations of traditional physiological models a nd a lso t he contemporary central governor model of metabolic control are outlined. We propose a new ‘conscious brain regulation’ model as a variation to the central governor model, which provides a simpler but mor e co mprehensive e xplanation of the many phenomena associated wit h p acing and fa tigue in spor t and exer cise from a psychophysiological p erspective. In chapter f our, self-regulatory s ystems f or developing skills and al so for monitoring training outcomes are identified and discussed. In p articular, the rate of perceived e xertion (RPE) f or monitoring training is suggested as a practical way of both setting and monitoring training across all mod es of exercise. The facilitating a nd debilitating role of psychological factors lik e mental t oughness, co ping s trategies and se lfconfidence ar e a lso disc ussed. P acing in relation to en durance activities is explored in ch apter five. The p hysiological an d psy chological d emands of activities l ike marat hon running, cycling, rowi ng and tri athlon ar e outlined. Although the ability to sustain high rate of work output continuously over time is i mportant, from a strategic perspective, fr ont loaded, fas t s tart p acing appears to b e optimal for most endurance events. Also , ass ociative co ping strategies appear to b e related to better per formance outcomes in h igh performance athletes. T his cha pter pr ovides t he r eader w ith a practical example o f s etting and monitoring e ndurance training using an example o f a RPE-based tr aining programme a llowing adoption o f an individualised training load. Although the role of p acing may no t be i ntuitively ap parent fo r p ower, strength an d speed events, in ch apter six we pr ovide t he r eader with information on the relevance of appropriate pacing strategies across anaerobic events. High intensity activities might also benefit from preparatory strategies to control arousal levels or ex pectancies. This chapter als o contains a se lfpaced system and practical example for t raining in power, strength and sp eed activities. In chapter seve n, pacing for t eam (in vasion-type) spo rts is discussed. Most t eam sp orts are i ntermittent in nature req uiring utilization of both a erobic and anaerobic energy systems. Pacing str ategies ar e a pparent i n team games, yet are more complex as energetic demands vary by position and the game situation. A multi-l evel pacing m odel is discussed based on observations in soccer, y et whi ch is applicable to all invasion gam es. A

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Preface

xix

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

practical example of s elf-regulatory tr aining f or te am s ports is provided. Finally, in chapter eight we outl ine a number of s ituations in whi ch s elfregulation of exercise might need to be acco mpanied by other extrinsic (support) t echniques. F or example, a ccuracy of self-perception is less developed in c hildren because of their inexperience and can also be distorted among all in dividuals when ho meostasis is co mpromised by il lness or medication. T he r egulation of e xercise behaviour in ch ildren, i n individuals with Multiple Sclerosis and the obese are examined.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

ACKNOWLEDGMENTS The authors would like to thank friends, colleagues and family for all their help, advice and assistance with preparing and proof reading this book. Tracy Edwards (MSc, Oxford) patiently led the proof reading process and for this we are ver y gr ateful. Er ika Borkoles (PhD, Hull) pr ovided much appreciated assistance and additional perspective. As inspiration, we would like to acknowledge Professor Tim Noakes who, in our opinion, remains the undisputed champion of exercise physiology. For Matt F itzgerald, w e gr eatly appr eciate his foreword to t his book and his meaningful contributions to t he literature wh ich prom ote se lf-regulatory exercise via a collection of books.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

AUTHOR BIOGRAPHIES

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Andrew M. Edwards BEd (Hons 1), MPhil, PhD

Andrew Ed wards g ained a P hD i n Ex ercise P hysiology fr om S heffield Hallam University in December 2003 and has since worked as an academic in the UK, New Zealand and Australia. He is a British Ass ociation of Sport & Exercise S ciences (BASES) accr edited s cientist and is th e D irector of th e Institute of S port & Ex ercise S cience (ISES) at James Cook U niversity, Cairns, Au stralia. An drew’s main re search in terest i s t he i nter-relations between fatig ue, p acing and hig h p erformance sport. He has written many original r esearch art icles and worked as a cons ultant to sever al pro fessional UK soccer clubs. In addition t o his academic a chievements, Andrew is a f ormer UK nationally ranked 400m hurdler and elite level rower/sculler. He competed at many national events in both sports, such as the AAA athletics championships and Henley Royal Regatta. In recent years he won the 400m and 400m hurdles at the N ew Zealand an d Pan P acific Masters ga mes r espectively. He is committed to ex amining t heory-practice in teraction in s port a nd exercise science. Contact details: [email protected]

Professor Remco Polman DPhil, CPsychol, AFBPsS, Csci Remco Polman’s initial training was in the Faculty of Human Movement Sciences at t he ' Vrije U niversiteit', A msterdam, The Ne therlands where h e

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

xxiv

Andrew Edwards and Remco Polman

gained a ' Doctorandus' qu alification ( 1992). F ollowing th is, he c ompleted a PhD degree at the University of York, England. Prior to commencing his current post as Professor and Research Leader in Active Li ving at V ictoria University (M elbourne, Australia), Rem co wa s Professor of S port and Exer cise Sciences and Di rector of the Centre of Applied S port and Exer cise S cience at the Uni versity of C entral La ncashire, Preston UK. He is a char tered psychologist by t he Briti sh Ps ychological Society (BPS) and an accredited sport and exercise psychologist by the Health Professions Coun cil in the UK. He is also accredit ed for psychological research by BASES and for pr actice, research a nd te aching by the Dutch Association o f S port P sychology ( VSPN). Remco has fu lfilled a n umber of roles with the Division of Sport and Exercise Psychology (DSEP) of the BPS, including c hair, chair el ect and honorary secr etary. His r esearch interests ar e diverse and incl ude stress, coping an d emotions i n s port an d exercis e, the psychology of (sport) injury rehabilitation; personality and sport and exercise (Mental to ughness, Ty pe D pe rsonality), ex ercise psy chology (special populations, e xercise pr escription) a nd a geing ( interaction be tween psychological and biomechanical factors).

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Contact details: [email protected]

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Chapter 1

EVOLUTION OF TRAINING AND PERFORMANCE

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

1.1. ABSTRACT The aim of this chapter i s to identify an d discuss inf luential factors pertinent to the evolutionary dev elopment of hu man athletic p erformance. Elite an d wo rld record performances are tracked fr om t he begi nnings of accurate r ecordings to the cur rent t ime. Th is analysis demonst rates th e commonalities of performance change o ver time and the relativ e performance plateau now commonly observed in el ite athletic events. The methodological evolution of training practices i s als o exam ined, thus com paring a nd contrasting sy stems w ith w hich t o or ganise, d istribute an d monitor training. The chapter concludes with an examination of issues surrounding the potential for sustainable performance gains.

1.2. INTRODUCTION The study of pacing in sport and exercise in a relatively new phenomena [1], yet the practice of distributing effort to finish (and perhaps win) a race is not new. To win a race requires the willingness to outperform others and such a des ire produce s beh aviours to achieve that goal. As one race i s won , oth er competitors seek to gain the upper hand and will also adop t new behaviours. This means future strategies fo r both tr aining a nd pe rformance must be developed to attain, or re- establish th e com petitive edge. Such competition

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

2

Andrew Edwards and Remco Polman

inevitably d rives up th e general s tandard of performance and th e emph asis placed on innovative and effective training practices. The distribution of effort (pacing) t herefore applies acutely to a n exercise b out and also t o the e ffort applied to systematically improve performance through dedicated training. Striving for excellence in athletic performance has historical basis [2] and the desir e t o win may be co nsidered cornerstone of co ntemporary society. However, there are ma ny fa ctors th at contribute t o athl etic success. By understanding the evolutionary development of elite performance, changes to training practices and the challenges faced in sustaining performance gains we may better understand the place of pacing in sport and exercise.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

1.3. EVOLUTION OF HUMAN ATHLETIC PERFORMANCE It is easily observable that in the i mmediate years followi ng the introduction of the m odern Olympics, fr equent im provements were rapidly made to wor ld r ecord p erformances ( Figure 1.1a and 1. 1b). H owever, s uch gains have now slowed to such an extent that it is possible the human species may be approaching its physical limits [3]. Based on evidence of exponential data tr ends, it has b een es timated performances have r eached ap proximately 99% of human capability and unless there is an unexpected change to human evolution, it is further predicted that most world records will no t be improved by more than 0.05% over the next 15-20 years [3]. Numerous investigators have ap plied e xponential m athematical m odels (e.g. [ 4]) to predict future ath letic performances a nd es timate the probable limits of human capabili ty. One event anticipated to demonstrate m inimal improvement is the 100 metres sprint. The 100m is the shortest Olympic track running distance and therefore represents an interesting test case for examining speed generation in humans. The firs t men’s 100m w orld record to be ratified by the International Amateur Athletics Fe deration (IAAF) was set in 1912 by Donald Li ppincott of the USA who r ecorded a time of 10. 6s [ 5]. This performance has now been improved to the current world record of 9.58s set in 2009 by Usain Bolt of J amaica; however, this only represents a pe rformance gain of 9.6% across 99 years to the present time (Table 1.1). For wome n, the f irst ratified 1 00m wo rld re cord w as set in 1922 Marie Mejzlikova II of Czechoslovakia who reco rded a time of 13 .6s [ 5]. This performance was a pproximately 23. 5% slower th an th e co mparative male world record of that time (Charlie Paddock: 10.4s) but that w orld record has

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

3

now improved to the cur rent t ime s et by Florence Griffith-Joyner in 1 988 (10.49s).

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Male 

Female 

Figure 1.1a (male) and 1.1b (female). Progression of male and female world record performances across selected track and field events (taken with permission) [6]. Note the rate of change in the javelin declined in the 1980s due to altered equipment specifications as competitors began to reach a level of performance that would mean throwing the javelin beyond the length of an athletics stadium.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Table 1.1. Progression of selected world track and field records from 1900 to 2011 Men

100m, time (date)

Women First record

Current record

Improvement (%)

First record

Current record

Improvement (%)

00:10:60 (1912)

00:09:58 (2009)

9.6

00:13:06 (1922)

00:10:49 (1988)

19.7

400m, time (date)

00:47:08 (1900)

00:43:18 (1999)

8.3

01:04:04 (1922)

00:47:60 (1985)

25.7

1500m, time (date)

03:55:08 (1912)

03:26:00 (1998)

12.4

04:17:03 (1967)

03:50:46 (1993)

10.3

10,000m, time (date)

30:58:08 (1911)

26:17:53 (2005)

15.1

32:17:20 (1981)

29:31:78 (1993)

8.5

Marathon, time (date)

02:55:19 (1908)

02:03:59 (2008)

29.3

03:40:22 (1926)

02:15:25 (2003)

41.2

Long jump, distance (date)

7.61 m (1901)

8.95 m (1991)

17.6

5.16 m (1922)

7.52 m (1988)

45.7

Shot put, distance, (date)

15.54 m (1909)

23.12 m (1990)

48.8

10.15 m (1924)

22.63 m (1987)

123.0

Time is represented as h:min:s.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Evolution of Training and Performance

5

Griffith-Joyner’s 100m record considerably closed the gender difference to its current level of 8 .7% a ndthe progression of th e w omen’s r ecord r epresents a 19.7% improvement from the first ratified world record to the present day. As Griffith Joyner’s record is often deb ated for legi timacy (e.g. it was windy that day) ev en substituting in t he winni ng performance from th e la st World Athletics Ch ampionships (Sh elly-Ann Fra ser of Ja maica: 10.73s), i t st ill represents a n improvement o f 21.1% across alm ost 90 y ears. This i s ov er double the performance change in men and explains the closed gap (23.5% to 8.7%) between genders [ 6]. There r emains considerable debate as to whether world record perfor mances between g enders are na rrowing to the exten t that males and females may one day c ompete e qually, or whether thi s gen der difference wi ll e ver close. However, th e gap b etween e lite spr inting performances of males and females has ceased to narrow substantially during the last 50 years and has even widened in some athletic events since the mid1990s [7]. It is p ossible that c urrent ge nder performance diffe rences may reasonably reflect true phy siological dif ferences bet ween ma les an d females [7]. Nev ertheless, it rem ains a viable possibility of natural s election that gender-specific differences in performance could continue to reduce. An explan ation of the lim ited ch ange in the men’s 1 00m sprint performance over t he las t 1 00 years is obvio usly related to the s hort performance time/duration, but may also be specific to that event in so far as sprint ability h as g eneric u sefulness to a wi de rang e of s ports activi ties. In 1912, the ability to sprint would have been a useful attribute for athletic males wishing to pe rform in Soccer, B aseball, American Football or ot her well known sports. Ther efore, elite ma le sprinters in 1912 wer e pr obably already well trai ned and likel y m ore so than co mparative women for whom competition was l ess s ignificant and opportunities for participation in organised sports less readily available. If sprinting to some extent represents an innate ability to maximally exert physical p ower on an at hletics track, long dis tance runn ing exemplifies different attri butes such as the wi llingness to resist the develo ping s ensations of fatigue an d bo redom over prolong ed activ ity. This is n ot to diminish the amazing ac hievements an d ha rd work of elite sprinte rs or the va lue of dedicated sprint training; however, it is possible long distance events may, to a greater extent, demonstrate th e impacts of more recentl y ev olving t raining developments such as perio dization and biotechnological tr aining techniques. Long distance events such as the marathon demonstrate greater change in elite performance over similar time frames to sprint events, having progressed from the first male record of 2:55:18.4 set by Johnny Hayes of the USA in 1908 to

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

6

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

2:03:59 by Haile Gebrselassie of E thiopia in 2008 [5]. This is a per formance improvement fo r m ales of 29.3%, while for fema les, th e wo rld re cord marathon perfor mance has improved fro m 3 :40:22 in 1926 (Violet Piercy o f the U K) to 2:15:25 s et by Paula Radcliffe of the UK in 2 008 (41.2% improvement). Anti dop ing c ontrol procedures, ex trinsic rewards, political bo ycotts of major even ts, two world war s and r ule modifications, ha ve all i mpacted o n sports participation and t he de velopment of w orld r ecords ov er t he las t 100 years. C onsiderable expansion of participating co untries and athletes in Olympic events has also occurred, increasing from only 14 nations competing in t he f irst modern Oly mpics of 1896 in Ath ens ( 240 co mpetitors), to 204 nations for the 2008 Beijing Olympics (11,028 competitors) [8]. Nevertheless, despite greater number s of elite competitors, gr eater acc essibility to modern training facilities and a growing world population, elite performance have not continued to improve linearly. This undoubtedly represents a slowing of gains in el ite level per formances and it is pos sible th is m ay eventually impact on consumer i nterest in s ports where sp ectators enj oy wit nessing world r ecords broken and new role models established based on their athletic achievements.

1.4. EVOLUTION OF TRAINING METHODS It is t empting to ass ume that modern tr aining te chniques s uch as periodization and state-of-art technologies are modern phen omena exclusively derived from co ntemporary trainin g pr actices out side of the sc ope and comprehension of ath letes in antiquity. However, this per spective would be na?ve and do a disserve to our athletic predecessors who were well known to complete phy sical training, prepare the mselves for athletic eve nts and also demonstrated understanding of th e as sociation between phy sical acti vity a nd health [9]. The earliest known records of physical activity are documented in ancient tomb drawing s of r itualised dance and hunting such as thos e d epicted in t he Lascaux Cav es approximately 13 ,000 BC [10 ]. H owever, th e earliest k nown records of planned, purposeful physical activity (exercise) for acquiring fitness or ot her health benefit s appear fr om approximately 2 500 BC in Ch ina. Surgeons at that time encouraged patients to participate in exercise for health benefits, m odelled on t he m ovement of an imals, chiefly the t iger. In mo dern terms, this would barely constitute plan ned exercise as we mig ht cons ider it, and s o the earliest evidence of a like -for-like structured approach to physical

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

7

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

training with whi ch to c ompare our cur rent pr actices is that of the ancient Olympians. The ancient Olympics w ere f irst d ocumented to be held in Olympia, Greece in the year 776 BC a nd continued to be c elebrated f or ov er on e thousand years, bro adly on a 4 -year cy cle [2]. Th is 4 -year c ycle h as been replicated in the modern Oly mpics, although we ar e some way short of achieving the longevity o f the ancient Olympics ( approx 112 y ears vs. 1 000 years). There were three main criteria for entry to the Gam es: the participants had to be m ale, of Greek origin and had to be free men [11]. Women, slaves and non-Greeks were therefore excluded. The programme of events lasted for five days and only individual sports were contested. These included equestrian events s uch as horse-drawn chariot r acing, p ugilism ( boxing), wr estling, athletic events such as the pentathlon (discus, long jump, javelin, run ning and wrestling), and se lected r unning events. For the r unning events, str aight li ne races were held as the stadium was rectangular and an oval track had not yet been introduced. Consequently, races were classified in terms of their relative length to the length of the stadium. There were four races [2]: 1. 2. 3. 4.

The stade (a sprint one length of the stadium: approx 192m) The diaulos (an extended sprint two lengths of the stadium: approx 384m) The dolichos (an endurance event, 7 to 24 lengths: approx 1300 – 4600m) The race-in- arms in which co mpetitors raced in ar mour wit h helmet a nd carrying a shield.

Potential participants f or t he O lympics had to g ive an undertaking t o individually train for 10 mo nths prior to the Ol ympics before tr avelling to a dedicated training camp four weeks before the Games to join other participants for an int ensive preparatory period. The specifics of either individual training practices or the intensive tr aining c amp ar e scant, but i t is c lear a f inal selection of s uitable athletes was made once all training had been completed. This process would be analogous to satisfying a se lection committee that the appropriate level of qualifying performance had been obtained. Although i t is common to view ancien t train ing meth ods at that time as unstructured and inferior to modern practices, t his vie wpoint may be misguided. For example, Philostratus (ca. 1 72-250AD) de scribed th e traditional Greek at hletic training system whic h wa s a four day cycle of activities, known as the tetrad:

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

8

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

“By t he tetrad system we mean a cy cle of fo ur da ys, ea ch one of which is devoted to a different activity. The first day prepares the athlete; the s econd is an all -out trial th e t hird is r elaxation; and the fourth is a medium-hard workout. ..[Regarding ] ex ercise of the first day, ..[it] is made up o f s hort, int ense movements whi ch stir up t he athl ete and prepare h im f or the h ard workout to follow on the next day. [T his] strenuous d ay is an al l-out test if h is p otential. The third [day ] employs his energy in a moderate way, while on the day of the medium workout [or last day], the athlete [himself] practices breaking holds and preventing his opponent from breaking away.” [12]

The tetrad sy stem is s imilar to th e modern concep t of periodization and yet is given little credit as the basis for cyclic exercise in which work and rest are c onsidered wit hin t he t raining plan ( Figure 1. 2). E ach cycle of the tetrad was designed to avoid overloading the athlete with consecutive high intensity training days and thus follows a fairly con ventional pro gramme of 1 ) preparatory exercises (day one), 2) very heavy training (day two), 3) rest (day three) and 4) mod erate intensity exe rcise ( day four). The completion of one such cycle would be followed by the f irst day of the cycle, meaning that moderate exercise was followed by preparatory (or perhaps technical) training, and thus leaving a reaso nable per iod for recovery between high intensity sessions. This or ganisation of the tr aining cy cle w ould minimise the r isk of overtraining and fac ilitate r easonable reco very f rom training wi th which to manage o verload and p hysiological adaptation to t raining st imuli. S uch concepts ar e obvious to ath letes an d coaches undertak ing training i n modern times and yet it is apparent this was in the case in ancient times too. Interestingly, t he limitations of fo llowing a reg imented, generic and inflexible training programme not accounting for diet and a holistic approach were also noted. The tetrad was therefore not without its critics: “While the gymnasts [coaches or athletic trainers] are following this fixed rou tine of the tetrad, they pay no attention to the condition o f th e athlete they are training, even though he is being harmed by his food, his wine, th e secret sn acks he eats, mental str ain and fatigue...How can we [prepare athletes] by a schedule of tetrads?” [13, 14]

Lucian (AD 120-ca 180) identified the need to vary the training stimulus, manipulate the training environment such as ground surface, and demonstrates an und erstanding for the n eed t o tr ain f or dis tance as well as s peed work f or the preparation of Olympic runners:

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

9

“We train [young men] to run, getting them to endure long distances as well as speeding them up for swiftness in the s prints. This running is not done on a firm springy surface but in d eep sand, where it is not easy to place one’s foot forcefully and not push off from it since the foot slips against the yielding sand.” [14] a  Preparatory exercise

Tetrad training cycle

Day 1

Heavy training Rest Day 2 Moderate exercise

Day 3

Day 4

0

20

40

60

80

100

Emphasis (% )

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

b 

Figure 1.2. Evolution of training periodization from the Greek tetrad (a) to modern periodization (b). Periodization (b) diagram taken with permission from Flueck and Eilers [19].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

10

Andrew Edwards and Remco Polman

Professional co aches had ther efore learned a practical appreciation of basic e xercise phy siology and the principles o f at hletic training; howe ver, medical philosophers at th e tim e d id not al ways agree th at h igh volumes of training were positive. Galen (c. 200- 129BC) for example, wrote an extensive essay on gymnastic exercises in a major work on health. He perceived that too much ex ercise wa s no t necessarily p ositive for health, an obse rvation consistent with m odern observations of gr eater sus ceptibility to i llness in response to high training volumes. Full-time athletes therefore did not always find favour with those who promoted physical culture for health. Galen q uotes Hippocrates who co nsidered th at professional ath letes trained to excess: [2].

“..the perfect condition which these fellows strive for is dangerous.”

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

As a consequence, the science of training theory was referred to as ‘Health Science’ an d wa s co nsidered w ithin th e sc ope of the tr ainer, whi le a new subject ‘hygiene’ was taught b y the physician and could perhaps be described in modern terms as ‘Sports Medicine’. “..athletes live a life quite contrar y to the precepts of hygiene, and I regard their mode of living as a regime far more favourable to illness than to health.” [14]

It i s i nteresting to also note at thi s t ime th at Nike was i nvolved in th e Olympics even i n a ntiquity. The Gr eeks co nsidered it was the gods who decided to gr ant v ictory to an at hlete. Vic tory was oft en r epresented in th e form of a winged female character k nown as Nik e, meaning ‘v ictory’ in Greek. However, as competitors performed nude in the ancient Olympics one could also assume performance was free of commercial endorsement. During th e Roman E mpire (up u ntil c. 500 A D) physical fitness was an essential military skill but was also seen in a more general context. There was a difference be tween the Ro man attitude to a thletic events an d the Greeks. Romans, although w illing to develop f itness thro ugh sport, did not enjoy public par ticipation in the sa me way as the Gr eeks. Public spec tacles of athletic pursui ts we re through combat-based ac tivities such a s gladiatorial events. Gladiator training was highly specialised, event specific work that was overseen by teams of coaches/trainers, many of whom were former gladiators. Equipment was state-of-art for that period of history and training was highly intense. Nev ertheless, multi spor t festivals m odelled on the early Olympic

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Evolution of Training and Performance

11

Games were never p opular am ong th e Romans. After the downfall o f th e Roman Empire and the beginning o f the Dark Ag es, t he Church becam e a dominant influence in many countries. The role of sport in society such as in Eng land at t his ti me was largely dictated b y re ligion and affairs of state. S port was not consistent w ith Puritanism and only became a more acceptable feature of society (particularly in B ritain) with t he decline of Puritanism. The later emergence of t he public school sy stem in England re-established th e be nefits o f sport, such as where sport was seen as exerting a pos itive, cha racter forming, an d stabilizing influence on th e youth. With thes e cha nging at titudes, sport was no t only encouraged for its physical benefits but also spiritually. In contrast to the Dark Ages, ex ercise was n ow considered a pr actical component of religion, hen ce the the 'muscular Christian' ethos, but as sport evolved further, it became not so much a means to an end, but an end itself [15]. Galen's early view that vigorous exercise could be harmful persisted into the nin eteenth centur y. It may have b een t his per ception that pr ompted JE Morgan ( 1873) [ 16] to stu dy the h ealth of t hose w ho had p articipated in t he Oxford vs C ambridge University Boa t Race. Morgan studied lon gevity a nd subsequent effect on health of university oarsmen who had participated in the first 4 0 y ears o f th e boat race fr om the years 18 29-1869. H e fo und that the average length of life for each oarsman after the boat race, assuming an age of 20, wa s 42.2 y ears. The n ormal e xpectation of life a t that time b ased on contemporary English life tables was 40 years. This su pported a positive role of exercise on long term health outcomes. Although the tetrad of ancient Greece identified athletes working in fourday training cycles, the modern schema of dividing a training programme into stages or cy cles ( periodization) or iginated i n Europe in the early twentieth century (~1910) [17]. C oaches beg an to s tructure training prog rammes to incorporate diff erent st ages for emph asis to tr aining, such as ge neral, preparatory and specific (pre-event) considerations [17]. In the 1920s and 1930s, more clearly defined cycles of training b egan to emerge. Exp erts b egan to recognize the need to clearly alte rnate per iods of work an d rest, to graduall y prog ress from hi gh-volume/low-intensity t o l owvolume/high-intensity tr aining close to a race and to h ave ea ch phase of training build on the training completed in the previous phase. During the 1950s and 1960s, pro minent N ew Z ealand r unning coach Arthur Lydiard refined the periodization concept to include base t raining, hill training and s harpening w ork [ 18]. Ly diard w as o ne of the f irst to di vide a training cy cle into di stinct phases and estab lish a defi ned order for the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

12

Andrew Edwards and Remco Polman

different types of training within them; however, it was not until the latter half of the 20 th century that the idea of per iodizing an athlete's trainin g b ecame common practice. The modern periodization training method divides a y ear of training into major periods called macrocycles, each about three to four months in duration [19]. The se macrocycles are fu rther subdiv ided into s maller mesocycles, which typically last three to four weeks (but can last up to 6 we eks) and even smaller microcycles, wh ich ar e ty pically on e wee k long [20]. T hus, thr ee t o four microcycles c omprise one mesocycle; and t hree to f our mesocycles constitute one macrocycle(Figure 1.2).. The final wee k o f a mesocycle is usually designed as a res torative micro cycle before und ertaking the work of the next mesocycle. This restoration period can involve both reduced training loads and periods of rest. The basic goal of periodization training is to introduce a series of training loads an d re covery t imes that provide a stimulu s fo r a daptation and su percompensation [21]. This causes overload (Figure 1.3), whereby the body (e.g. muscles and physiological sy stems) is periodically stress ed in response to higher than normal work. The body adapts and thereafter is able to work more efficiently at a higher work. I f the tr aining stimulus is too s mall in eit her intensity or duration, lit tle or no adaptative ov erload will t ake place (Figure 1.3). Conversely, if the stress is too severe, the adaptation could be delayed or may even b e compromised. Ther efore, de termining an appropriate tr aining load for each individual is a key consideration to opti mising athletic potential. A one-size fits all approach to training is rarely the answer. The L ydiard-style p eriodization o f training i s known a s linear periodization because th e va rious ma jor tr aining stimul i (e.g . aerobic, anaerobic, str ength or spe ed) a re la rgely se gregated f rom eac h oth er in the training pr ocess a nd are ar ranged in a l ine s uch that each makes way for the next. This approach is disti nct fr om nonli near p eriodization, in which th e various training stimuli are mixed together throughout the training programme and only the emphasis or importance of each component changes from cycle to cycle. There ar e s everal major cr iticisms of Ly diard-style l inear periodization systems. For example, many experienced coaches and athletes believe that the sudden introduction of h igh-intensity tr aining after a le ngthy period of lowintensity training carries a high risk of muscular injury. A second criticism is that the various importan t aspects o f running fitness are not developed in unison [ 22]. This is particularly the cas e whe n str ength a nd speed characteristics are developed in diff erent phases of tr aining, only for the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

13

athlete to experience so me extent of d etraining i n one while th e oth er is practiced. Finally, linear periodization systems are also criticized for requiring months of d edicated (linear) pr eparation towards a sp ecific g oal r ather t han facilitating numerous goals across a competitive period or season. Meso cycle 4 Meso cycle 3

Performance

Meso cycle 2 Meso cycle 1

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Fatigue

Recovery

Figure 1.3. Principles of overload whereby performance in response to each cyclic period of training (mesocycle) results in fatigue and subsequent adaptation and progressive performance gain. The solid diagonal line represents performance gain in response to four consecutive mesocycles.

Nonlinear periodization att empts t o a ddress al l of these li mitations by mixing to gether th e various major training stim uli throughout the training cycle. The pr esence o f si multaneous strength a nd s peed tr aining ac ross the training period may mini mize injury risk and retain p erformance to a greater extent [ 20, 2 2]. It also gives athletes more f lexibility to co mpete w hen required. As athletes are therefore continually in a reasonable broad-base state of conditioning, they can achieve a peak for a particular event fairly quickly by appropriately increasing the emphasis and p revelance of race-like t raining characteristics. Ther e is t herefore no requirement to wait f or each fitness component to be a dded t o the pr ogramme linearly one by one. In li near periodization, outco mes can be difficult to quan tify tho ugh as t raining intensities and loads can b e much more difficult t o disc ern a mid a s eries of training targets within the overall training plan (Figure 1.4).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

14

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 1.4. An example of outcomes for training volume and intensity in response to nonlinear periodization resistance training.

Most of the more recent pe riodization system s a re ba sed o n n onlinear principles [22]. One example is the multi-pace tr aining method developed by David Martin and P eter Co e [ 23], whic h cha nges t he emphasis w ithin cy clic training pe riods without dedicating t he whole t raining schedule to one modality, or specific focus. This enables sev eral strands of training to be progressed simultaneously while the specific emphasis can still be maintained. This has been suggested to minimise risk of injury as it removes the necessity for broad base change of training when changing the phase of training [20]. Training methods have certain ly evolv ed to the extent wher e ph ases of training, e mphasis of components of fi tness, sp ecific goals, and methods of determining intensity of effort are all par amount to achieving optimal balance. However, rather than being a c ompletely new concept it appears such training is an ev olution rather than a m odern invention. In m any ways, t raining methodologies may hav e r eached th e s tage at wh ich they h ave beco me too complicated and a simpler i ntuitive ap proach such as self-paced an d selfregulated exercise may prove optimal. Fleck summarised [20]: "We h ave, in th e USA, overdone o veranalyzed a nd overplayed periodization. We have created too many rules, to the stage where it is too daunting to wade through the plethora of literature to gain or i mply any practical use.”

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

15

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

1.5. THE CHALLENGE OF SUSTAINING PROGRESS In antiquity, body masses were approximately 70% of curr ent values [24]. In m odern tim es, ( 1900-2002), the mean hei ght of h umans has in creased by approximately 5cm, w hile over the s ame perio d, the mean height of elite swimmers and r unners incre ased by 11 cm and 16cm, re spectively [ 25]. F or many s ports ther e appear to b e spec ific phy sical or anthr opometric characteristics tha t i ndicate suitability, or potential, to c ompete a t t he highes t level. I n basketball, the heights an d masses of al l retired NBA players are significantly pos itively associated (p < 0.01) with the length of car eer and regression analysis suggests player body mass equates to, on average, an extra year in career len gth [ 26]. For exa mple, it has been es timated that,for every extra 1.0cm in h eight or 1.3k g in mass, this co rresponds to ap proximately $US43,000 in additional player payments over a career [26]. In soccer, differences in age, stature, b ody mass a nd B MI have be en observed and these differences vary across different European soccer leagues. For e xample, goalkeepers and defenders tend t o be o lder than o ther ou tfield players suggesting that they have longer careers wit h increased earning potential. In addition, on average, players in the Spanish, Italian, English and German soccer leagues are taller and leaner than the secular population of their respective countries [27]. Spanish soccer players were, for example, 7cm taller than the general Sp anish population [27]. Of co urse s port is evolving on a continuing ba se an d s o ar e the a thletes co mpeting in th ese sports. Olds [ 28] provided some evidence f rom Rug by union to suggest that chan ges in t he physical characteristics of players is ab ove and beyond t hat of the se cular population. For example, rugby players showed significantly greater increases in body mass and BMI in comparison to the normal population. The demands of the diff erent sports and th e possible rewards mean that for m any to reach and/or survive in profess ional sport they may be tempted to adopt illegal and dangerous behaviours with which to modify body size and shape. Different sports and playing positions within team games appear to require specific morphologies for success and thus role-specific physical characteristic requirements are now common. Since 1980, the rate of increase in body mass and height has been observed through evaluation of BMI among sports people. This has shown an approximate increase in body size of 0 .159 BMI u nits per year. In addition, studies involving the anabolic steroid androgen showed that, even in doses much lower than those used by athletes, muscular strength could be improved by 5–20% [29].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

16

Andrew Edwards and Remco Polman

Although improv ed n utrition, biotechnologies and u p to d ate training practices ma y contribute to th e ob served change in el ite per former morphology; it i s a lso li kely that b oth legal and ill egal ergogenic aids are influential. F or ex ample, Ben Johns on is sug gested to have s tood to gai n an estimated $US30 million in endorsements for his 1988 Olympics sprint victory [30]. It is difficult to deny the attraction of such an incentive. In response to announced d rug testing, less th an 1% of Oly mpic a thletes during th e 1980s (19 84 to 1 989) wer e found to te st p ositive [2 6] which suggests d rug tak ing in s port is a rela tively minor is sue. H owever, t his low percentage is misleading as i t is w idely acce pted that t he u se of illegal performance enhancing drugs is one of the greatest problems facing sport. To put th is issue in per spective, [ 31] it h as been r eported that whe n the US Olympic Committee conducted unannounced drug tests involving no punitive actions, ap proximately 50 % of athletes tested posi tive to anabolic steroids. There is also c onsiderable colloquial e vidence t hat in sp orts s uch as NFL American Football, steroid use in some positions may be as high as 90% [32]. The International Amateur Athletic Federation estimates that only 10–15% of participating a thletes are tested in ea ch m ajor competition [33] a nd so m ost athletes are relatively unlikely to ev er undergo testing. As a consequence, the risk of expulsion is relatively low in relation to t he p ossible gains. This i s unsurprising given the financial and publicity incentives for reaching the upper echelons in professional sport. Elite athletes can earn many millions of dollars every y ear in prize money, sponsorships and e ndorsements. The extrinsic rewards of success are therefore great, but the penalties relatively minor. The issue of drugs in s port has b een hotly deb ated fo r many y ears with researchers such as Haugen [34] predicting that where the risk of being caught is zero, all athletes will choose to cheat. The enormous rewards for the winner, combined with the e ffectiveness of t he dru gs, and t he l ow rate of tes ting al l interact to create an environment of loosely accepted cheating [35]. However, due to th e apparent necessity of ideal physical condition, body size and shape for high pe rformance s port, we may b e placing modern a thletes in an untenable position. It is conceivable that cheating could eventually be the only option f or success as ev en athl etes with id eal physical attributes may no t consider elit e level p erformance ob tainable wit hout pharmaceutical support. One could question whether i s it mo rally rig ht to place su ch expectations on athletes while denying them effective pharmaceutical aids. Savulescu and colleagues [ 33] su ggested t hat perhaps the answer to t he dilemma of drugs in sport might be to simply allow all performance enhancing drugs. In support of this argument it has been pointed out that many classical

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Evolution of Training and Performance

17

musicians use ? blockers to control performance anxiety as these drugs lower heart r ate and b lood pr essure, thereby r educing t he effects o f s tress. I t h as previously been s hown t hat th e quality of a m usical pe rformance gene rally improves if the musician tak es thes e dr ugs [36] and y et there is n o stigma attached to the use of the se drugs in the performance of music. The au dience assesses the pe rformance a nd the use of pha rmaceutical ai ds is la rgely irrelevant to that context. There are many examples of tenuous legality and selective morality in the limitations of accept able cheating in s port. For exampl e, there i s li ttle difference of intent b etween e levating blood cou nt by alti tude training, by using a hypoxic air chamber, or by injecting erythropoietin (EPO). The aim is largely the same for each, although results are only consistently effective with the latter [37]. It is the EPO fo rm of blood doping which is the only activity not per mitted. Assu ming altitude and hy poxic training proved consistently effective, it is l ikely th ey to o would be banned. Yet s ome c ompetitors ha ve naturally hi gher p acked r ed b lood cell s, or have better su ited muscular characteristics to a giv en activity, each of whic h is an adv antage b y genetic good fortune [35]. Some individuals can afford hypoxic chambers for training; some liv e at altitude, or ca n aff ord r egular train ing trips to suitable environments. Some gymnasts are more flexible, and some basketball players are seven feet tall. It is apparent that nature has not dealt us all an equal hand. It h as additionally been proposed th at any legali zation o f performanceenhancing drugs in sport, if it were to occur, would need to be s ubject to limitations [37]. However, this i s a self defeating argument as th e presence of any imposed limit on per missible drugs enco urages a thletes to seek ou t and exceed such l imitations in th e q uest of the co mpetitive edge. An il legally obtained competitive edge is not so simply circumvented as to allow a free(er) environment for doping. If there were a legalization of performance enhancing drugs in sports, the athletes m ay be inclined to ad opt greater risk t aking behaviour which could mean world records are extended beyond the extent of that achievable in drug fr ee performances. In the short ter m, this might satisfy the viewing public, media and sponsors but does not address th e issu e of whether this is a moral or fair situation for athletes who are seeking to reach the top in their event. If an athlete strives to reach the top, he or she can only realistically try to beat the co mpetition at the time of racing. Whet her or not this requires a world record performance is largely irrelevant compared to the specific goal of simply out performing the opposition. Placing the athlete in an untenable p osition r equiring personal health risks to achieve this goal i s no t consistent wi th a morally resp onsible modern soci ety and sur ely canno t b e

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

18

Andrew Edwards and Remco Polman

permissible. It could be considered exploitative of impressionable, vulnerable individuals who are phy sically able a nd wil ling t o d ope for the avarice of spectators and media. This is not a situation we should condone. Performance enhancing drugs primarily facilitate the desire of t he athlete (or coach) to improve performance in excess of that otherwise perceived to be achievable. This is presumably in response to an ide ntified need or deficiency recognised in the athlete, a lthough this as sessment may often be made un der false assumptions. Th e desi re to improve, to seek o ut wa ys to improve and adopt practices to ou t perform others i s perfectly natural an d en tirely consistent with the evolution of sport. Improvements can also be accomplished legitimately, especi ally if ap propriate drug t esting i s ad opted systematically across all sports. There then remains the question of how performances can be optimised in the absence of illegal drugs? This question can be address ed by understanding the mechanisms of how physical performance is managed. The simple ex planation is that hu mans dist ribute e ffort a cross the d uration o f an exercise bout (or race) in relation to: 1) the known demands of the task, 2) an innate se nse o f th eir physical ca pabilities and 3) their motivation to suc ceed. Nevertheless, t his explanation r equires considerable el ucidation suc h a s the ways in which effort is applied, whether or not it is possible to increase effort, where this e ffort is best applied, a nd what ar e th e phy siological a nd psychological mechanisms that potential r estrict a ll voluntary ef forts? Although the mechanisms un derlying the applica tion o f effort are h ighly pertinent t o p erformance of al l phy sical tasks, i t is an area o ften neglected. This is, in many ways, surprising as Triplett identified the concept of pacing as long ago as in 1897 [38 ], and y et his o bservation w ere largely ignored. As a consequence, the study of pacing r emains an emerging ar ea of r esearch in contemporary sport and exer cise science [39]. It is ther efore the pur pose of this book to thoroughly describe the role of pacing across contemporary sport and exercise situations.

CONCLUSION •

•

It is now predicted that without an unexpected change to human evolution most world r ecords will not be im proved by mo re than 0.05% over the next 15-20 years. Analysis of elite s printing p erformance be tween males and f emales demonstrates t hat current gen der pe rformance di fferences ma y now reasonably re flect true p hysiological d ifferences bet ween males and

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Evolution of Training and Performance

•

•

•

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

•

•

• •

19

females. The ancient Greek t etrad sy stem of tr aining is s imilar to the mo dern concept of periodization and yet is given little credit as the basis for cyclic exercise in which work and rest are considered within the training plan. Each cy cle of the tetrad was d esigned to av oid overloading t he at hlete with consecutive h igh in tensity t raining d ays a nd thus follows a fairly conventional p rogramme of 1 ) p reparatory exercis es (day on e), 2) very heavy tr aining ( day two), 3) r est ( day thr ee) a nd 4) mo derate intensity exercise (day four). The modern sy stem of linear per iodization trai ning div ides a year o f training int o major periods called ma crocycles, ea ch about thr ee to four months in d uration. The se macrocycles are furt her subdivided into mesocycles, which typically last t hree to four weeks (but can last up to 6 weeks) and microcycles, which are typically one week long. Criticisms of li near per iodization systems include: 1) ma ny c oaches and athletes b elieve th e su dden introduction of high-intensity ex ercise af ter low-intensity training carries a risk of injury; 2) various important aspects of training are not developed in unison through this training system and 3) it requires months of dedicated preparation towards a specific goal rather than simultaneously facilitating several goals. Nonlinear periodization att empts t o a ddress al l of these li mitations by mixing t ogether the v arious major trai ning s timuli wi th differential emphasis throughout the training cycle. Different sp orts and play ing p ositions appear t o requ ire specific morphologies. It has b een suggested that to remo ve unfair advantage in sport, it may be simplest to a llow all per formance enhancing drugs. Th is co uld be considered exploitative of impressionable, vulnerable individuals who are physically able a nd willing to do pe f or the avarice of sp ectators and media.

REFERENCES [1]

Foster, C., et a l., Effect of pa cing stra tegy on c ycle time trial performance. Medicine & Science in Sports & Exercise, 19 93. 25 : p. 383-388.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

20 [2] [3] [4] [5] [6] [7] [8] [9]

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[10] [11] [12] [13] [14] [15] [16]

[17] [18]

Andrew Edwards and Remco Polman Robinson, R., Sources for t he hi story of G reek a thletics 1980: Ares Publishers. Berthelot, G., et al., Exponential g rowth co mbined with exponen tial decline explains lifetime performance evolution in individual and human species. Age, 2011. Online ahead of print(ONLINE). Berthelot, G., et al., At hlete aty picity on the edge of hu man achievement: pe rformances stag nate a fter the la st peak, in 1 988. PLoS ONE, 2010. 5: p. 1-8. IAAF, IAAF world championships in athletics : I AAF statistic s handbook. Daegu. IAAF Media & Public Relations Department, 2011. Lippi, G ., e t a l., Upda tes o n imp rovement of h uman at hletic performance: f ocus on wo rld re cords i n at hletics. British Medical Bulletin, 2008. 87: p. 7-15. Seiler, S ., J. D. Koning, and C. F oster, The f all and r ise of the ge nder difference in elite a naerobic p erformance 19 52–2006. Medicine & Science in Sports & Exercise, 2006. 39: p. 534-540. IOC, Factsheet. International Olympic Committee, 2011. Galenus, C., De par vae pilae exercitio, in Medicorum Graecorum opera quae exstant, C. Kuhn, Editor. 1964, G. Olms: Leipzig. Williams, J. , Med ical as pects of spo rt and p hysical f itness. 1 965, London: Pergamon Press. Crowther, N., Athle te an d state: q ualifying for the O lympic Ga mes in ancient Greece. Journal of Sport History, 1996. 23: p. 34-43. Philostratus, F., Con cerning gy mnastics ( Translated), i n The Research Quarterly, T. Woody, Editor. 1936, Ann Arbor: MI. Bowie, E. and J. Elsner, Philostratus. Greek culture in the Roman world. 2009, New York: Cambridge University Press. Grivetti, L. and E. Applegate, F rom Ol ympia to Atlanta: a culturalhistorical perspective on diet and athletic training. Journal of Nutrition, 1997. 127: p. 860S-868S. Holt, R., Sport and History: the state of the subject in Britain. Twentieth Century British History, 1996. 7: p. 231-252. Morgan, J., University oars being a cr itical enquiry into the after health of men w ho rowed in th e O xford and C ambridge Bo at Race from t he year 18 29–1869, based o n th e personal experience o f th e rowers themselves. 1873, London: McMillan. Pedemonte, J., Fou ndations of training p eriodization. Par t I: His torical outline. National Strength and Conditioning Journal, 1986. 8: p. 62-65. Lydiard, A. and G. Gilmour, Run to the top. 1962: AH Reed, NZ.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Evolution of Training and Performance

21

[19] Flueck, M. and W. Eiler s, Training mo dalities: impact on endurance capacity. Endocrinology and Metabolism Clinics of North America 2010. 39: p. 183-200. [20] Fleck, S . and W. K raemer, The ul timate training s ystem: p eriodization breakthrough. 1996, New York: Advanced Research Press. [21] Bompa, T. and G. Haff, Per iodization: Theory and methodo logy o f training. 5th ed. 2009, Champaign IL: Human Kinetics. [22] Fleck, S., Periodized strength training: A c ritical r eview. Journal of Strength and Conditioning Research, 1999. 13: p. 82-89. [23] Martin, D. and P. Coe, Better training for distance runners 2nd ed. 1997, Champaign IL: Human Kinetics. [24] NHANES, Nat ional health and nutr ition exa mination sur vey: a verage weight for an adult man, 1999-2002. 1999. [25] Charles, J. and A. B ejan, The evo lution of sp eed, s ize and s hape in modern athl etics. The Journal of Experimental Biology, 2009. 212: p. 2419-2425. [26] Norton, K. and T. Olds, Morph ological evol ution of athl etes over the 20th Century: caus es and consequences. Sports Medicine, 2 001. 31 : p . 763-783. [27] Bloomfield, J., e t al., A nalysis o f age, statu re, body m ass, BMI a nd quality of el ite s occer pl ayers from 4 european leagues. Journal of Sports Medicine and Physical Fitness, 2005. 45: p. 58-67. [28] Olds, T., Th e evolution of physique in male rugby union players in the twentieth century. Journal of Sports Sciences, 2001. 19: p. 253-262. [29] Hartgens, F. and H. Ku ipers, Effects of androgenic-anabolic steroids in athletes. Sports Medicine, 2004. 34: p. 513-554. [30] Lucas, J., Future of the Olympic Games. 1992, Champaign (IL): Human Kinetics. [31] Voy, R., Drugs, sport and politics. 1991, Champaign (IL): Leisure Press. [32] Yesalis, C., A nabolic s teroids in spo rt and ex ercise. 1993 : Champaign (IL): Human Kinetics. [33] Savulescu, J., B. Foddy , and M. Clay ton, W hy we s hould allow performance enhancing drugs in sp ort. British Journal of Sports Medicine, 2004. 38: p. 666-670. [34] Haugen, K., The perfo rmance-enhancing drug g ame. Journal of Sports Economics 2004. 5: p. 67-87. [35] Noakes, T., Sh ould we allow performance-enhancing drugs in sport? A rebuttal to the article by Savulescu and colleagues. International Journal of Sports Science & Coaching, 2006. 1: p. 289-316.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

22

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[36] Brantigan, C., T. Br antigan, and N. Joseph, Effect of beta blockade and beta stimulation on s tage fri ght. American Journal of Medicine, 19 82. 72: p. 88-94. [37] Wiesing, U., Should performance-enhancing drugs in sport be legalized under medical supervision? Sports Medicine, 2011. 41: p. 167-176. [38] Triplett, N. , The dynamogenic f actors in p acemaking and competitio n. The American Journal of Psychology, 1897. 9: p. 507-533. [39] Foster, C ., e t a l., Pa cing stra tegy a nd athletic pe rformance. Sports Medicine, 1994. 17: p. 77-85.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Chapter 2

AN INTRODUCTION TO PACING IN SPORT AND EXERCISE

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

2.1. ABSTRACT The aim o f t his chap ter is t o identi fy, de fine a nd discuss the conceptual bas is of pacing in sport and exe rcise. Evidence of behaviour consistent with paci ng exi sts in animals and hu mans, y et lev els of organism co mplexity di ffer between species. Decisi on-making an d responsiveness t o afferent se nsory information are consistent f eatures in many species, with each demonstrating a coping behaviour with which to avoid catastrophic physical exhaustion. Th is suggest s that pacing is a mechanism with wh ich to manage the co mpletion o f a s pecific t ask in relation to the known d emands and the perceived physical capabilities of the ind ividual. For hum ans, co mmonalities o f pacing stra tegy also exist and it seems likely these are driven by personal and situat ional demands. Typical pacing strategies are categ orised and th eir particular applications to performance are discussed in this chapter.

2.2. INTRODUCTION Pacing is a r elatively new ar ea of r esearch wi thin s port a nd ex ercise science. To our kn owledge, there is not yet a wo rking def inition o f what is meant by pacin g an d it is likely t hat a definition to satisfy all th e diverse attributes of pacing wi ll still remain elusive. Nevertheless, for the purpose of understanding the aut hors’ interpretatio n of pacing in resp onse to sp ort an d exercise, we propose the following definition:

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

24

Andrew Edwards and Remco Polman

Pacing: ‘The goal directed distribution and management of effort across the duration of an exercise bout.’ This is a definition of th e topic which best fits our view of paci ng in this book. Pacing is a strategy with which to manage effort across an exercise bout in relation to a specific goal and in the knowledge of the likely demands of the task. It is widel y recognised that individuals distribute effort thro ughout an exercise bout and it is this dis tribution of applied work that has already been loosely termed pacing [1]. Yet, pacing does not purely apply to elite athletic performances. It is al so in evidence during all non -reflex exercise situations where in dividuals are ab le to r eceive and act on neur al f eedback fr om peripheral phy siologic systems [2, 3]. Y et little is kn own o f th e sp ecific physiological, cognitive and/or environmental factors that affect or control the distribution of work during exercise [4, 5].

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

2.3. THE CONCEPT OF PACING The 1 980 Oly mpics games held in Moscow was r emarkable for s everal sporting and non sporting reasons. It was the first time a major sporting event had been subject to substantial political boycott, the last time a Caucasian male won the 100 metre sp rint [6] a nd also be cause it was th e a rena for in tense competitive rivalry between two British middle distance runners (Figur e 2.1a and 2.1b).

Figure 2.1a and 2.1b. The agony (800m) and ecstasy (1500m) of Sebastian (Lord) Coe vs. Steve Ovett at the 1980 Olympic games (with permission from Topham Picturepoint).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

25

Both runners were suprem e athletes and each was in peak physical condition. Sebastian Coe was the cur rent wor ld r ecord holder for the 80 0 metres ( 1:42.33 min:s a t t hat ti me) a nd S teve O vett had r ecently set a new world reco rd for the 1500 metres (3: 32.09 min :s), marginally b ettering th e previous record set by his rival, Coe [ 7]. Each w as sc heduled t o co mpete i n both 800m and 1500m events with Coe the favourite fo r the 800m and Ovett the 1500 m. The fact th at Ovet t then won t he 800m race while several day s later Co e wo n the 1500m is not s o rema rkable in itself as middle dis tance runners ar e of ten able t o perform similarly well acr oss these two d istances. However, it was the ma nner of Coe’ s defeat in the 800 metres th at was unexpected, parti cularly as he was p laced l ast after the f irst 400m lap. Considering the race leader completed that lap in a relatively modest time of 54.55s, it should ha ve be en well with in Coe’s cap abilities to b e placed somewhere other than last. At that stage of his career, Coe had a personal best performance of 46.87s for 400m [7] and yet, in the most important race of his career so far, he sp ent th e 2 nd 4 00m lap running in an ou tside lane and attempting to accelerate past all the other competitors from last place. It is not surprising he didn’t win t he race from that situation and it wa s actually quite an achievement that he managed t o ov erhaul everyone els e e xcept f or Ove tt and claim the si lver medal. Yet, Ovett’s winning ti me of 1:4 5.4 minutes was 3s slower than Coe’s wor ld r ecord. This duration r epresents a lifetime in the competitive world of middle distance running and it i s perhaps a race Sebastian Coe has run over in his mind more than once, subsequently selecting a different r ace ( pacing) str ategy. A sl ow start to the ra ce was also not the strategy he chose for the 1500m a few days later. The s cientific study of p acing has previous ly been d escribed as ‘the unexplored territory in spo rt performance’ [1] and, until recen tly, few studies had examined th e influence of p acing on e xercise performance [ 8]. This is surprising as the distribution of effort is an integral part of racing, but this also suggests that a voluntary behaviour (effort) may limit performance rather than the absolute capacity of a s ingle physiological system [9]. For example, many experimental studies have assumed athletes run to the point of exhaustion and cease exercise directly as a consequence of depleted fuel sources, severe local muscle acidosis, a limiting co re body tem perature, deh ydration or other examples of a system failure [ 10, 11]. Howev er, no ne of t hese f actors h as consistently been shown to b e cau sal to exercise-induced fatig ue. Each variable may be strongly associated with the sensations of fatigue and declines in work outputs, but such associations do not infer causality.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

26

Andrew Edwards and Remco Polman

Perhaps the most logical way of view ing pa cing is to consider it as a neural buffering pro cess to prevent premature ph ysical exhaus tion. Th is buffering process may avoid the necessity to conclude an exercise bout prior to its scheduled finish, or attain an unnecessarily high peak power output prior to the specific point where it is most required, or expend too much energy on one exercise bout wh en the task requires sus tained p erformance quality acr oss a series of activities. Pacing is not a perfect process and some people are better at it than others. Nevertheless, it is a pparent that the ability to a ccurately pac e o neself can b e improved with training o r, if not by t raining, with ex perience [1 2]. Prior experiences o f simil ar cir cumstances whether in spo rts, day -to-day life, or clinical exercis e rehabilitation s ettings are important feat ures i n the ability to pace [4]. If pacing is a buffering mechanism to ena ble people to successfully complete t asks, th en prior ex perience an d accurate kn owledge of the task demands are crucial to success [ 9]. I t is the coupling of pr ior ex periential knowledge a nd acc urate a wareness of t he task d emands that en ables us to consider th e requirements for likely su ccess in relation to o ur indiv idual capabilities [ 12]. The more accurate th is knowledge, th e m ore likely pacing will accurately reflect o ur int entions or maxi mal capability. These intentions might be to simply complete a race, perhaps to win it, to work at a fixed effort level during training, or to complete a series of tasks while distributing efforts across each. In sport, it is know n that individuals p erform less well in unfamiliar circumstances [ 9], when the d emands o f the task are unclear [ 13] and th at impaired performance o ccurs p rior to the abs olute fa ilure of any single physiological system [14]. In all exercise situations, voluntary power output is immediately reduced when individuals are confronted with adverse conditions such as extreme heat i n comparison t o n eutral c onditions [ 15] an d certainly well in advance of any phy sical necessity to d o so. I t h as also be en demonstrated that dif ferences in po wer out puts f or endurance e vents ar e evident in the fir st minutes of ex ercise between c arbohydrate l oaded and normal carbohydrate conditions, while me tabolic f uel st orage of glycogen is still high i n b oth [16]. This sug gests p acing is est ablished in an ticipation of, and not after, physiological system failure, especially as individuals appear to run down fuel stores to sim ilar po st-exercise co ncentrations (i.e. not fu lly depleted) of muscle glycogen regardless of initial starting levels [16, 17]. The concept of pacing is not exclusive to sports and race performances. It applies to almost all exercise situations [18-21] as will be demonstrated in this book. The concept of pacing dictates that effort is distributed to facilitate task

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Introduction to Pacing in Sport and Exercise

27

accomplishment at the pe rceived inten sity requ ired by the individual. Th e requirements of the individual depend on many factors and are not restricted to the physiological limitations of the hu man body. As sub sequent chapters will identify, no single phy siological system demonstrates cat astrophic sy stem failure du ring exercise in he althy sub jects. A lso, n o single phy siological variable ac curately pre dicts a thletic pe rformance [9] and it is the purpose of this book to iden tify the r ole o f pacing i n this c onundrum and mo re importantly to discuss the factors that influence pacing. It should be apparent at this stage that the pr otective buffering role of pacing cannot be investigated purely f rom a ph ysiological perspect ive. As p acing is an informed decision based on accu rate knowledge of p ast and present factors [4], it must also b e considered a psy chological i ssue. The int eraction of physiological and psychological factors i s cr ucial to pacing an d m ore generall y to human performance. Therefore the philosophy of this text is to view the human body from a psychophysiological pe rspective w hereby phy siological and psychological components contribute to the complexities of behaviour.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

2.4. THE ORIGINS OF PACED ACTIVITY Although the study of pacing is a relatively new concept, the premise that both humans an d an imals ex hibit behaviour consistent with pacing is not novel, n ew, or ev en sp eculative. The abilities o f e fficient and effective locomotion ar e im portant to the survi val of all species [ 22, 23]. Hunting, foraging, or avoidin g predators are all achievement based outcomes [24] and the mor e co mplex the or ganism, th e greater the co mplexity of behaviour and task ex ecution. The principles of na tural sel ection [25] infer that the most successful at achieving their outcomes will provide the future genetic basis of their pop ulation. A slow mo ving animal, pr one to premature fa tigue, and unable to respond to environmental demands would seem an unlikely evolutionary forerunner. Organ isms adjust b ehaviour to th e s timulation they receive from the environment [26] and the orig ins of pacing are perhaps best described through investigation of behaviour-environment interactions. It is well noted in laboratory studies that single cell amoeba display simple avoidance behaviour in response to stimulation wi th mech anical shock, weak electric cur rents, and light [ 26]. This is as a co nsequent to sensitization to a single stimulu s. Am oebas d o not poss ess a br ain; ho wever, as organism complexity increases, greater sophistication of behaviour is observed.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

28

Andrew Edwards and Remco Polman

The concept of condit ioned learn ing w as neatly dem onstrated b y I van Pavlov [27]. Pavlov observed that dogs salivated when a bell was rung if th e sound o f th e bel l had p reviously o ccurred while th e dog had the pleasurable sensation of m eat in it s mo uth. Pavlov p roposed the over lap i n time of th e meat in the mouth with the sound of the bell resulted in the creation of a neural association between the two stimuli, such that the sound was able to substitute for the meat and elicited saliv ation. Pavlov called the meat an unconditioned stimulus, the bell a co nditioned s timulus an d the s alivation res ultant to the conditioned s timulus a co nditioned r esponse. The s alivation of th e dog was therefore a learned (conditioned) behaviour in response to a stimulus. The cognitive abilities of birds are also now appreciated as more complex than p reviously assumed [ 28]. Pigeons for ex ample, h ave been sh own to b e able to m emorize u p to 725 different visual patterns, wh ile par rots can learn human words and use them to communicate reciprocally with humans. In cold environments, birds adjust their posture to contribute to heat conservation [29] while in hot environments they voluntarily seek out shade and remain inactive [30]. This is inherently sensible behaviour. Reptiles hav e br ains s imilarly organized to birds due to t heir common ancestry. Repti les ar e capable of both non- associative ( response-stimulus reflex) an d associative learning s uch as when a sa ltwater cr ocodile noti ces a routine p attern o f behav iour in a poten tial prey and l ies in waiting for an opportunity to str ike. Reptiles are a lso t he f irst vertebrate c lass in whic h a neocortex is present in the b rain (site of conscious th inking), but this is minimally develo ped and so h igh o rder co nceptual learning is generally considered beyond their scope [31]. As a moeba, mammals, b irds, an d r eptiles a ll demonstrate the ability to interact with their environments it seems unlikely that environmental triggers would not fo rm p art of a sens ory process infor ming exercis e beh aviour. If a bird is able to recognize the need for shade on a hot day [28, 30] so to avoid overheating, then a human is also perfectly capable of this behaviour. Animals d emonstrate a m ultitude of complex behaviours. Predators such as large cats (e.g. lions) are only ever intermittently active, while lizards also exhibit s top/go movement patterns, ev en w hen p ursued. Migratory bi rds sustain constant motion during long flights and dogs such as the Cape Hunting dog or wolves are capable of tracking prey for extens ive periods [32]. Despite this o bvious diversity, th e c ommonality of all animals is the ou tcome driven nature of their l ocomotion. Each animal ha s morphological an d biochemical differences whi ch make it su ited t o its uni que lifestyle and aims. It is uncommon to observe an ani mal fall short in achieving its aim. It m ay fail to

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

29

execute the ta sk (e.g. a lion ma y m iss capturing a gaze lle) b ut w e d o not observe it continue the chase un til it reaches abs olute exhaustion. That is unless s ome unexpected environ mental circumstances den y th e animal its usual means of recovery. Therefore, a lio n does not ru n itself to exhaustion, a Cape H unting d og trac ks an animal for 2 5-50 minute s be fore re sting a nd reassessing new prey targets [ 33], migratory birds land early if adverse wind speeds precl ude r eaching the expected destination [28], and lizard s do no t exhaust the mselves, even when pursued [23, 34]. None of thes e an imals possess the cognit ive abilities of human an d yet all are ab le to respond effectively to t heir env ironments. All thes e organisms have a brain which receives s ensory feedback and each a dopts behaviour i n response to this sensory inform ation. Th e main difference be tween sp ecies re sts on wh ether that behaviour is instinctive, or consequent to a conscious cognitively-derived decision. Instinct is an i nnate, unlearned p attern of resp onse [31]. Instin ctual behaviour is therefore fixed b y permanent neu ral patterns which ar e genetically deter mined and pass ed on to f uture ge nerations. In contrast, learned (acqu ired) beh aviour is gen erally co nsidered t o be a result of experience. Laboratory-bred rats, for example, will freeze if they encounter a cat, d espite n ever having p reviously seen o ne [3 5]. Freezing is ther efore a built-in ( innate) response and s imple behaviours d o not require conscious decisions (i.e. they are automated, sub a ware behaviours). Humans, like other animals, receive afferent feedback to inform us o f such sensations of hunger, thirst, ex cessive heat storage or nausea in the p resence o f metabolic disturbance. T hese se nsations g radually grow i n se verity i f we t ry t o ignore them and if we do not c hange o ur be haviour; they the refore s timulate us to adopt s ensible behav iours to avo id phy sical damage. I n so me sit uations, the sophistication of the human is als o its limi tation; in other words, our superior cognitive abilities enable us t o i gnore, ra ther than im mediately a ct o n t he feedback information our bodies are providing.

2.4.1. Case Study: Cheetah, Acinonyx jubatus The cheetah is a rather special animal and worthy of closer inspection in the study of pacing and behaviour. In many ways, the behaviour of the cheetah is similar to our own, in so far as it recognises the demands of a given task, has a pl an of how t o ex ecute the task, r ecognises whe n t he desired o utcome is likely or unlikely to be achieved and it also learns from experience.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

30

Andrew Edwards and Remco Polman

The cheetah has a de ep chest, small waist and proportionally longer limbs than the other big cats [36]. An average adult male cheetah weighs 43 kg [37], it has r elatively small canines which allows for a larger n asal aperture, facilitating increased air i ntake during r ecovery fr om activity while it suffocates its pr ey by throttling it. However, what makes the cheet ah a cause c?l?bre of the animal kingdom is its ability to reach incredible speeds. A cap tive ch eetah has rep ortedly been observed to reach 112 k ph over a short dis tance with 0 -60 kph acceler ation not u ncommon within 3 seconds [38]. Antelopes, the main prey of cheetah reach top speeds of 80-97 kph [34] and so although the peak speed of the cheetah is exceptional; it is a necessary capability f or its hunting pr actices. N evertheless, cheetah hunts are relatively brief and seldom last longer than 200-300m (e.g. 10-15s). Cheetahs have be en o bserved to h ave a s uccessful hunt t o ki ll ratio of approximately 6:1, although this improves to 4: 1 in open gr asslands where it has the b est opportunity to use its p ace [ 38]. S tudies in the Nairobi National Park found that cheetahs had significantly longer chase distances in successful (189m) than i n u nsuccessful hunts ( 96m). The s uccess o f longer ch ase distances indicates that cheetahs are able to gauge their chances of success and decide to give up early if failure is predicted. In this way, energy is conserved, exhaustion avoided an d further h unts rem ain v iable. Any longer distance (>300m) unsucce ssful hun ts are g enerally in itiated by ju venile cheetah, suggesting that, as with h umans, (prio r) ex perience is a key factor i n th e hunting process. Learning an d gaining ex perience from tria l and error is of course a ke y feature in developing succ essful be haviour. Thus earlier recognition of likely success in animal hunting in rel ation to the specific task is consistent with human (anticipatory/predictive) p aced be haviour ( Figure 2.2).

Figure 2.2. Humans and Cheetahs: both exhibit pacing behaviours in response to the known demands of a task (www.scenicreflections.com).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Introduction to Pacing in Sport and Exercise

31

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

2.5. PSYCHOLOGY OF PACING Whilst phy sically ac tive or exercis ing, humans have t he abi lity to consciously process afferent sensory information arising from the internal and external e nvironment and make de cisions ba sed on t his information. In comparison, a sy stem bas ed ent irely on har dwired r eflexes t o d eal wit h al l sensory s ignals woul d be i nfinitely large, sl ow to r espond and cumbersome. The capacity to make conscious decisions in this respect has allowed humans to optimise their behaviour [39]. This provides a huge evolutionary advantage. Information reaching th e centr al n ervous sy stem has fo ur ch aracteristics: quality, intensity, duration, and hedonicity [39]. Quality, intensity and duration provide positive information and are multiplicative. Hedonicity (how useful or harmful an even t is) pr ovides positive, negative or neutral information and is additive in n ature. Hedonicity refer s to our ca pacity t o associate different sensations with pleasant or unpleasant responses. It is hig hly likely t hat the consci ous s ensation of effort cons ists of a combination of peripheral and central sen sory i nformation. Hence, the perceptions of effort or perceived ex ertion are not based on a single sensation but an amassing of multiple signals. The Borg scale of perceived exertion [40] in t his r espect assesses o ur global perceptions ar ising f rom the internal environment. Thi s m ental repres entation has been sh own to be as g ood a measure of e xercise i ntensity as physiological p arameters s uch as heart r ate [41]. According to Cabanac [3 9], behaviour is regulated by hedonicity, commonly known as the pursuit of optimizing pleas ure. Pleasure in his view equals use fulness. Engagement in mu scular exer tion therefore is th e r esult of direct or indirect motives. There is evidence that muscular exertion in itself is rewarding and imp roves m ood [42, 43] and its instigation ca n th us b e intrinsically motivated. Also, acutely sustained muscular activity itself can be unpleasant, howev er the resulting r eward compensates for th e feelings of unpleasantness. In sport, individuals often engage in training regimes which are extremely strenuous and not pleasurable at all. So w hy would a thletes b e mo tivated to experience high levels of displeasure? Cabanac [39] has suggested that there is a trade off between our ability to tolerate displeasure and the anticipated future rewards. An athlete might train extremely hard because his desire to run faster, jump f urther or make t he soccer squa d outweigh tha t of f eeling immediate pleasure. The athlete is abl e to delay gratification to a future point in time. As such, the s election of a b ehavioural r esponse or the way we pace ou r s elf

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

32

Andrew Edwards and Remco Polman

during exercise is based on phy siological properties (e.g. anaerobic threshold) as we ll as t he i mmediate or f uture n eeds of th e indiv idual ( achieving f uture gains). The latter would explain why an exerciser or athlete engages in training practices whilst ignoring ot her hedonic messages ( fatigue, pai n). The a thlete might not l ike the training session but c ontinues b ecause o f th e pleasure experienced in the foreseeable future. To achieve o nes goals, i t is key tha t indi viduals are motivated. As outlined, this m otivation m ight co me from within the individual (intrinsic) because of the enjoyment or pleasure derived from the activity or alternatively from o utside ( extrinsic) sources such as r ewards, t hreats or compet ition. Hence, co mpetition indicates th at t he athlete p articipates in the event to beat opponents rather than f or the i nherent pl easure of the ac tivity itself. Besi des Cabanac’s explanation why ind ividuals might engage i n exercise t here ar e a large nu mber of other m otivational theories. A nu mber of th ese motivational theories are concerned with the needs of individuals. One such theory is S elfDetermination Theory (SDT) [44] . According to SDT individ uals h ave t hree needs to be autonomous, competent and feel r elated and connected to others. SDT has be en a succ essful theory in predicting eng agement in spor t an d physical activ ity. A cognitive moti vational theory relevant to p acing is goal theory or achievement motivation theory [45, 46]. According to t his theory individuals can have two goal orientations. Task goal or ientation refers to the i ndividual being i nterested in the mastery of a particular ski ll, to g et better at it. E go goal orien tation refer s t o individ uals who are i nterested in demonstrating their superior ability in competition with others rather than self-improvement. Mast ery an d ego goal o rientation are independent constructs and individuals c ould be high in b oth, low in b oth or high in one and low in the other [47]. More recently other goal orientations have been proposed. Social approval goal orientation ref ers to s ocial acceptance through co nformity to nor ms. In addition, Gernigon et al . [ 48] suggested th at indiv iduals m ight hav e an orientation to av oid emba rrassment or defeat (in co ntrast to bea ting the opponent). Both goal orientations would have consequences for pacing. Social approval goal o rientations are associated wi th d isplaying max imum effort whereas goal orientations to avoid failure would result in individuals putting in just enough effort not to fail. Also important for pacing is the motivational climate created in which the sport or exercise takes place. The sporting environments can also be classified as either task or e go-oriented. A task oriented environ ment would emph asise and reward e ffort, cooperation a nd improvement, whereas an ego- oriented

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

33

environment i s ch aracterised b y encouraging competitio n an d punish ing mistakes or poor performance. There is evidence to s uggest that th e individual’s g oal-orientation and the m otivational cli mate int eract and m ight influence the way athletes behave in such an environment [49]. On the whole, both, individual goal orientation and motivational climate appear to be f actors which are likely to influence the way athlet es or exercisers r egulate their behaviour and therefore pace their exercise bouts or competition performance. Self-efficacy is defined as the ‘beliefs in one’s capabilities to organise and execute the course of action required to produce given attainments’ [50]. Selfefficacy h as been show n to be a co nsistent predictor of at hletic performance and has been associated with more effort, persistence, and higher performance levels. For exa mple, Moritz et al. [51] f ound, i n their meta-analysis, a moderate positive relationship (r = .38) between sport specific skill-based selfefficacy and a thletic performance. I f an at hlete believes t o be in control and has the ability to p roduce certain outcomes than he/she will be motivated and happily engage in the activity. An a thlete w ith high levels of ef ficacy is a motivated athlete who is likely to work hard to succeed. There is also evidence that g roup se lf-efficacy b eliefs re sult in hi gher p erformance le vels [5 2]. Although not specifical ly researched to d ate i t is ap parent that indivi dual or group self-efficacy beli efs ar e lik ely to influence sp orting or exercise behaviour and as suc h the pacing strategies adopted by athletes and exercisers during training and competition. Two p sychological concepts wh ich h ave also been shown to influence athletic p erformance ar e a nxiety and sel f-confidence. Since t he wor k of Spielberger [53] it is now wel l es tablished th at th ere i s a distinction be tween anxiety as a personality characteristic (trait-anxiety) and anxiety as a transient mood s tate ( state-anxiety). State- anxiety is the ‘r ight now’ feeling of apprehension and t ension in a specific situation [54] whereas trait-anxi ety is a general disposition to fee l anxious in cert ain environmental s ituations [55 ]. Research ha s shown that pe ople wi th high levels of tr ait anxi ety are more likely to interpret a situation as t hreatening than peop le low in trai t anxiety [56]. To achieve sporting excellence it is generally believed that athletes need to possess a hig h d egree of self- confidence [ 57]. This co nstruct has been perceived by both athletes [58] and coaches [59] to be a salient characteristic in order to achieve success. Meta-analytic studies have provided evidence for this contention [60]. An additional psychological state associated with outcome in sport is preperformance mood state. Mood has been defined as “a changing non-specific

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

34

Andrew Edwards and Remco Polman

psychological di sposition to evaluate, in terpret, and act on past, current, or future conc erns in certain pa tterned ways” [ 61]. Mo od dif fers from e motions in terms of its cause, consequence, and intention. That is, emotions are specific to a par ticular e vent, fo cuses on spec ific obj ects, and inf luences b ehaviour. Mood, on th e other han d i s a co nsequence of minor even ts and internal metabolic or cognitive processes, is u nspecific in its direction, and influences cognition [62]. A meta-analysis [63] found a small-to-moderate effect of mood on performance (mean Effect Size = 0.31). In particular, effects were moderate for vigour, co nfusion, and depression, s mall fo r anger and tens ion, an d very small for th e fatigue subs cale of the Profile of Mo od States qu estionnaire (POMS). Mood has been found to influence decision making [64] attentionalfocus [65], an d motivation [66 ]. C onsequently, like state anxiety and selfconfidence, mood is likely to influence the selection of the pacing strategy for the upcoming competition or training event. It is apparent that a number of psychological constructs might have direct or indirect influence on the way an athlete select a p acing strategy. Although these r elationships have n ot b een explicitly tested so me o f th e evidence suggests that these psychological con structs will det ermine th e athletes intentions which in turn will influence the strategy adopted for the task at hand as well as the maintenance of this strategy during performance. It is also likely that t hese ps ychological cons tructs interact w ith physiological s tates and behaviour and th at the inter action eff ects b etween thes e v ariables ha ve additional influence.

2.6. PERFORMANCE AND PACING STRATEGY The observation of Steve Ov ett beating Seb astian Coe in the 1980 Olympics 800m final i s ha rdly analogous t o t he t ortoise b eating the hare; however, it de monstrates that a runner with a slower personal best performance time is capable of winn ing if the mar gins between athletes ar e relatively minor and decision making is required as part of the activity. How an a thlete distr ibutes wor k an d energy thr oughout an exercise bout c an profoundly impact performance [5] and, in elite competition, a well executed pacing strategy may mean the difference between 1st and last place. Strategy is a cognitive process of planning action(s) designed to achieve a particular goal [1]. In many exercise situations, strategy is pre-conceived prior to task execution, particularly in tasks of s hort duration such as ve rtical jumping. I n these cases, all the n ecessary information is already he ld by the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

35

individual prior to the task. This situation is referred to as an open-loop control system as s ensory information is either not required or the task is s imply too brief to facilitate action modification as a consequence of the feedback. Where the individual has sufficient time to consider the implications of sensory neural feedback and co nsequently modifies action, it is referred to as a closed-loop control system [4]. Therefore, a single vertical jump may not require sensory feedback f or the purpose o f t he p erformance ( open l oop control), b ut if t he individual w ere r equested to p erform a series of repet itive vertical jumps (closed lo op co ntrol) this would r equire the dist ribution o f effort ( pacing) in response to c onsiderations such as the number of bouts and t he physical condition of the i ndividual [2]. Consequently, i t could be ex pected that peak performances would be diminished in a series of bouts compared to a maximal single, o ne-off ef fort whi le en ergy is co nsciously ma naged a cross the entire series. Closed loop co ntrol of ex ercise, fo rms the found ation of p acing. In response to exercise, afferent (towards the centre) in formation is sent by peripheral ( e.g. muscle, skin, or gans) r eceptors to the brain [ 2]. T his sens ory information is used to modify behaviour. It can also can be influenced by selfawareness (anxiety, self-confidence), previous experience of similar situations, environmental, and situational c onsiderations such as th e dur ation of t he exercise b out [67]. The se f actors inf orm the str ategy and its effective execution. Nevertheless, in many exercise situations there is often little time to deliberately plan a s trategy, or even to a djust a pre-planned strategy. Therefore, greater familiarity with one’s ca pabilities and the circu mstances of the task can lead to reductions in the processing time of information and refine the execution of appropriate strategic action. Pre-planning of pacing strategies f or exer cise s ituations not previously encountered can lead t o misjudgements in pace [ 14, 68] . This is due t o inaccurate estimations of individual capabilities and uncertainty of the specific demands of the task. In these circumstances it is relatively common to adopt a more circumspect approach to th e starting pace of the exercise bout [ 1] while intra-bout sen sory information i s process ed and the tas k d emands are dynamically evaluated [4]. I naccuracies of pacing c an al so le ad to over estimations of in dividual capab ilities (p articularly among novice e xercisers) and re sult in o ptimistically hi gh initial p ower o utputs o r ve locity. This potentially presents serious issues in situations where the individual has a pr e existing health condition. I n exer cise cases am ong h ealthy in dividuals it i s unlikely t hat an overly o ptimistic approach to pac ing i ntensity wi ll re sult in anything other than premature sensations of fatigue (e.g. overheating, muscle

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

36

Andrew Edwards and Remco Polman

pain, nausea), wh ich will req uire a b ehaviour modification to d own-regulate effort at an earlier than optimal stage to avoid exhaustion. Athletes generally learn pacing strategies in training as a consequence of physical practi ce [1]. Th is process is also infor med by observatio ns of other successful at hletes, and advice from coa ches. Ther efore, optimal pa cing may depend on n umerous facto rs such as experience, p rior knowle dge and self awareness in similar circumstances [12]. The ty pe of exercise task be ing performed can i nfluence t he e xtent of strategic planning involved in the task execution. For example, in head to head competitions, athletes ar e r equired to directly compe te agai nst e ach other whereas in t ime-trial ev ents, indivi duals c ompete against the clock [ 8]. F or success in a head to head race the winner simply needs to be faster than that of the ot her competitors. The strategic plan in this circu mstance, places greater emphasis on managing physical resources efficiently while retaining sufficient reserve of energy in case it is requ ired for a f inal ‘end spurt’ to outsprint an opponent [69]. In contrast, time-trial performances tends to produce more even pacing a s the a im is s imply to fi nish the r ace in the shortest ti me with n o requirement to retain energy for a ny other pu rpose th an the avoidance of physical harm. The evidence f or p acing, rather t han s imply running to exhaustion in response to head to head racing has recently been demonstrated by Noakes and co-workers [ 70] in an examination of la p times for w orld mile record performances b etween 1 886 and 1 999. Over t hat period ther e wer e o nly 2 races (from 32) in which the final lap was the slowest of the four lap race. In 24 of the 32 races (76%), the fi nal lap was either the fastest or slightly slower than the opening lap, while in 90% of t he races, the mid dle two laps were slowest. T he presence of th is final end spurt of speed n eatly supports the presence of a common pacing strategy in which a reserve of energy is retained in the final stages during head to head races (Figure 2.3). Studies in short duration events (120s), laboratory studies h ave found that p erformances m ay benefit fr om strategies in which po wer output and energy are distr ibuted mor e e venly [1]. As t he duration of t he e xercise event extends, a n e arly pe ak power i s of less consequence to the race o utcome and so a fast s tarting s trategy i s l ess consequential to performance. Th at is, unless t actical/positional requirements enhance the specific relevance of a fast start [72].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

38

Andrew Edwards and Remco Polman

Studies focusing on pacing strategies have tended to examine differences in performance d uring t he f irst a nd second hal ves of a race ( i.e. spli t times) [73]. However anal ysis o f race split times is a relatively si mple or gross analysis of one’s overall pacing strategy and may miss more subtle variations of p ace within a l ap. Th e r ecent development of more a ccurate a nd r eliable power a nd tim e me ters has allowed scie ntists to specifically ex amine performance profiles during field co mpetitions [74, 75]. Nevertheless, pacing strategies in r esponse to athletic a ctivities can be categorised according t o common characteristics of power output or velocity profiles [1, 5, 12, 76, 77]: 1) positive, 2) negative 3) even, 4) all-out, 5) parabolic-shaped, and 6) variable pacing strategies (Figure 2.4). A positive pacing strategy is one in w hich power outpu t or velocity gradually declines throughout the duration of the event. Positive pacing could be referred to as a d epletion-based pacing strategy in which energy gradually diminishes over the course of the event towards event completion. This type of power output or speed profile is consistent with the popular view of exercise physiology in which peri pheral m uscle or m etabolic fu el vari ables are gradually exhausted. An event is con sidered to h ave b een performed with a negative pacing strategy when ther e is a n increase in power output or v elocity obser ved over the durati on of the event. A negative-style paci ng st rategy is occasi onally observed during middle dist ance ev ents when po wer ou tput and velocity are increased to wards th e e nd of the e vent. This fi nal end spur t in exercise intensity co mmonly occ urs when a thletes ar e made aware of the r emaining distance or duration. During mo re prolonged events the st arting pace has less of an e ffect on overall performance times because of the lower percentage of time spent in the acceleration phase [1]. As such, it ha s been sugge sted th at an even pa ced strategy may be op timal for p rolonged (> 2min) lo comotive events su ch a s running, swimming, rowing, skiing, speed skating and cycling [78, 79]. All-out pa cing strategies a re those in which th e athlete comm ences the exercise bo ut ma ximally and thereafter at tempts to ma intain max imal power output for the duration of the bout. This is perhaps the least cognitive strategy and could be construed as a non-paced strategy. However, even in a short duration exercise bout resources must be managed but are probably done so at a s ub awar e lev el rath erthan co nsciously. Alt hough all -out exercise implie s maximal work will be achieved for the duration of the bout, physical resources gradually decline over the bout.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

39

Figure 2.4. Six commonly observed pacing strategies. Note for panel d (all-out pacing), the aim (dotted line) may be to retain maximal power output/velocity but practical observations suggest this will deteriorate and produce a profile similar to positive pacing, albeit with a higher initial power output. The parabolic-shaped strategy (e) produces several variations of power/velocity as U, J or a reverse J shape.

Parabolic-shaped pac ing is that wh ich demonstrates a fast s tart fo llowed by a progres sive r eduction in pow er or speed during the middle of an endurance trial but tends to increase during the latter portion of the event such as by the production of an end sp urt. This tactic us ually results in U, or J or reverse J-shaped pacing strategies.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

40

Andrew Edwards and Remco Polman

Evidence f or su ch a pacing stra tegy w as sho wn by Garland [ 75] who examined the v elocity of el ite rowers dur ing Ol ympic and World Championships. I n each o f th ese 20 00m r aces, rowers compl eted the first 500m in the fastest time, slowed during the middle 1000m but increased speed during the final 500m of the race. This r esulted in the adoption of a reverse Jshaped pacing strategy. It i s unco mmon fo r athletes to experience con stant e xternal conditions during act ual out door competition. Under t he var ying extern al con ditions associated w ith f ield r ace conditions it has b een sug gested that a variable pacing s trategy ma y be optimal in so me cases whi ch po wer o utput or speed frequently fluctuate [80]. These fluctuations may be influenced by a number of external factors including race duration, course geography and environmental conditions, such as wind and environmental temperature. From a practical athletic perspective, pre-planning a race strategy using an appropriate situation-specific strategy may be a u seful way to distribute effort and optimize performance for that event. However, this also pre-supposes that pacing is p urely a pre- conceived ( anticipatory) not ion and this form of prior planning does no t facilitate dy namic variat ions to s trategy d uring a n ev ent, unless of course a variable (free) pacing strategy is selected. In consideration of t his, Ed wards an d N oakes [ 81] de vised an alternative p acing model specifically designed for te am (invasion-style) ga me p erformances (see chapter seven) but which may also be applied elsewhere. In this model, pacing for an event (e.g. a soccer match) is considered at three levels: macro, meso, and micro. At the macro level, o verall d emands of the task ( e.g. match) ar e appraised p rior to th e task and an appropriate level of en ergy expenditu re is distributed over the course of the t ask by the pl ayer in accordance with b oth intrinsic and extrinsic considerations. At a meso level of pacing, major events may occur during the exercise task (e.g. match) such as a change in the score, tactical team alterations, positional change, or re-evaluation of strategy at halftime. Meso-pacing evaluations may therefore inform the overall macro pacing strategy and lead to ad justments of pacing if co nsidered necessary. Instantaneous variations of pa ce dur ing the t ask are considered a t a micro pacing level in which the metabolic cost of a short sprint may be evaluated in relation to t he higher order macro strategy. As such, an intense period of high energy sp rinting may lead to sub sequent rest or tactical behavioural changes such as tracking or passing the ball rather than the more demanding tasks such as tackl ing or dribbling u ntil the play er perceives sustainab le metabolic demands have b een re established and the immediate (micro) activity will not

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Introduction to Pacing in Sport and Exercise

41

compromise the overall pacing plan i.e. a pre-set level of tolerable discomfort the individual is prepared to ensure for the specific event (match). The circumstances, co nsequences a nd s cientific b asis of ea ch pa cing strategy will be consi dered in greater depth in subsequent chapter s a nd i n specific relat ion to the demands of di fferent ex ercise s ituations. There is currently no evidence to suggest a single type of pacing strategy is common to all f orms of exer cise and situ ation-specific strategies ar e l ikely to be appropriate for m ost goals. Ho wever, for m ost race and time-trial a ctivities, numerous s tudies h ave broadly identified a r elatively fast starting strategy as preferential to most circumstances although there ar e several variations to this approach [5, 80].

CONCLUSION •

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

•

•

•

• •

•

Pacing defined: ‘The goal directed distribution and management of effort across the duration of an exercise bout.’ In sport, it is know n that individuals p erform less well in unfamiliar circumstances and this impairment o ccurs prior to the f ailure of any physiological system. In shor t duration exercise ( e.g. v ertical ju mp), str ategy is pr e-conceived prior to task execution. I n th ese cas es, a ll t he ne cessary infor mation is already held by the individual prior to the task. This situation is referred to as a n op en-loop control sy stem as sensory infor mation is ei ther not required. Where t he individual has sufficient time t o consider t he i mplications of sensory neural feedback and co nsequently modify action ( e.g. a s eries of vertical jumps, or when r unning and so o n), it is r eferred t o as a closedloop control system. The most lo gical way o f vie wing pacing is to consider it as a neural buffering process to prevent premature physical exhaustion. The ab ilities of e fficient and ef fective locomotion are i mportant to the survival of all sp ecies. Huntin g, forag ing, or avoid ing pred ators ar e all achievement based ou tcomes a nd th e more comple x the o rganism, the greater the complexity of behaviour. Pacing s trategies in response to at hletic activ ities can be categorised according to common characteristics of power output or velocity profiles: 1) po sitive, 2 ) n egative 3 ) ev en, 4) all- out, 5) par abolic-shaped, and 6)

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

42

•

Andrew Edwards and Remco Polman variable pacing strategies. To achieve a goal it i s key that the in dividual is m otivated. This motivation might co me fr om within (in trinsic) becaus e of the enjoyment or pl easure d erived fr om the act ivity or from ou tside (ext rinsic) so urces such as rewards, threats or competition.

REFERENCES

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[1]

Foster, C ., e t a l., Pa cing stra tegy a nd athletic pe rformance. Sports Medicine, 1994. 17: p. 77-85. [2] St Cl air Gibson, A . and T. N oakes, Evid ence for complex system integration and dynamic neural regulation of skeletal muscle recruitment during exercise in humans. British Journal of Sports Medicine, 2004. 38: p. 797-806. [3] Noakes, T., A . St Cl air Gi bson, and E. Lam bert, Fr om cata strophe to complexity: a novel model o f integrative cen tral neu ral r egulation o f effort and fatigue during exercise in humans: summary and conclusions. British Journal of Sports Medicine, 2005. 39: p. 120-124. [4] St Clair Gibson, A., et al., The r ole of in formation proces sing between the brain and peripheral physiological systems in pacing and perception of effort. Sports Medicine, 2006. 36: p. 705-722. [5] Abbiss, C. an d P. Lau rsen, Des cribing and understanding pacing strategies duri ng athletic co mpetition. Sports Medicine, 2008. 3 8(3): p. 239-252. [6] Wallechinksy, D. , The compl ete b ook of the Oly mpics 200 8: Aurum Press Ltd. [7] Miller, D ., S ebastian Coe: born t o r un. 1 992, L ondon: Pavillion Books Ltd. [8] Foster, C., et a l., Effect of pa cing stra tegy on c ycle time trial performance. Medicine & Science in Sports & Exercise, 1993. 25 : p. 383-388. [9] Noakes, T. , Ti me to move beyond a br ainless e xercise phy siology: t he evidence for complex regulati on of human exerci se p erformance. Applied Physiology, Nutrition and Metabolism, 2011. 36: p. 23-35. [10] Costill, D., H . Thom ason, a nd E. R oberts, Fr actional utilization of the aerobic capacity during distance running. Medicine & Science in Sports, 1973. 5: p. 248-252.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

43

[11] Bassett, D . and E. H owley, Limi ting fa ctors for ma ximum oxyge n uptake and determinants of endurance performance. Medicine & Science in Sports & Exercise, 2000. 32: p. 70-84. [12] Tucker, R . and T. N oakes, Th e ph ysiological regulation of pa cing strategy dur ing e xercise: a c ritical r eview. British Journal of Sports Medicine, 2009. 43: p. 1-9. [13] Paterson, S. and F. Marino, Effect of deception of distance on prolonged cycling pe rformance. Perceptual and Motor Skills, 2004. 98: p. 10 171026. [14] Lambert, E ., A. S t Clair Gibson, an d T. Noa kes, Complex systems model of fatigu e: integrative ho moeostatic control of p eripheral physiological sy stems d uring exercise in humans. British Journal of Sports Medicine, 2005. 39: p. 52-62. [15] Dugas, J., e t a l., Rates of fl uid i ngestion alter pa cing but no t thermoregulatory responses during prolonged exercise in hot and humid conditions with ap propriate conv ective cooling. European Journal of Applied Physiology, 2009. 105: p. 69-80. [16] Rauch, H ., A . St C lair Gi bson, a nd E. Lambert, A si gnaling rol e for muscle glycogen in the regulation of pace d uring prolon ged e xercise. British Journal of Sports Medicine, 2005. 39: p. 34-38. [17] Rauch, L., et al., Effects of carbohy drate lo ading on muscle gly cogen content and cy cling p erformance. International Journal of Sport Nutrition, 1995. 5: p. 25-36. [18] Low, D., M. Gramlich, and B. Engram, Self paced exercise program for office wo rkers: im pact on prod uctivity and heal th outcomes. AAOHN Journal, 2007. 55: p. 99-105. [19] Day, M. , et al ., Mon itoring exer cise intensity during resistance training using the s ession RP E scale, Journal of Strength and Conditioning Research, 2004. 18: p. 353-358. [20] Impellizzeri, F., et a l., U se of RPE-based training load in so ccer. Medicine & Science in Sports & Exercise, 2004. 36: p. 1042-1047. [21] White, P ., et al., P rotocol f or the PACE trial : A randomised controlled trial of a daptive pacing, co gnitive behaviour th erapy, and graded exercise as supplements to sta ndardised specialist me dical car e versus standardised s pecialist me dical car e al one for pa tients with the chronic fatigue sy ndrome/myalgic encephalomyelitis or encephalopathy. BMC Neurology, 2007. 7: p. 1-20. [22] Garland, T., Scaling the ecological cost of t ransport t o body m ass in terrestrial mammals. The American Naturalist, 1983. 121: p. 571-587.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

44

Andrew Edwards and Remco Polman

[23] Garland, T., Physiological cor relates of lo comotory performance in a lizard: an al lometric approach. American Journal of Physiology, 19 84. 247: p. R806-R815. [24] Christian, K. and C. Tracy, The effect of the thermal environment on the ability of hatch ling G alapagos l and iguanas to avoid predation du ring dispersal. Oecologia, 1981. 49: p. 218-223. [25] Darwin, C., On the origin of species by natural selection. 5th Edition ed. 1872, New York: Appleton. [26] Cloninger, C. an d G illigan, Neuroge netic mechanisms o f learning: A phylogenetic perspective. Journal of Psychiatric Research, 1987. 21: p. 457-472. [27] Pavlov, I ., Co nditioned ref lexes, ed. T. G. V. Anrep. 1927, New York: Liveright. [28] Jarvis, E. and e. al., Avian brains and a new understanding of vertebrate brain evolution. Nature Reviews Neuroscience 2005. 6: p. 151-159. [29] Whittow, G., Sturkie's avian physiology. 5th Edition ed. 1999: Academic Press. [30] Dawson, W., Physiological stu dies of desert b irds: presen t and fut ure consideration. Journal of Arid Environments, 1984. 7: p. 133-155. [31] Thorpe, W., Le arning and instinct in a nimals. 1956, C ambridge, Massachusetts: Harvard University Press. [32] Kramer, D. and R. McLaughlin, The behavioural ecology of intermittent locomotion. American Zoologist, 2001. 41: p. 137-153. [33] Taylor, C., et al., Eff ect of hyperthermia on heat balance during running in the African hunting dog. American Journal of Physiology, 1971. 220: p. 823-827. [34] Garland, T., Scaling maximal running speed and maximal aerobic speed to body m ass i n mammals and liz ards. The Physiologist, 1982. 2 5: p. 338. [35] Blanchard, R. and D. B lanchard, Effects of hippocampal lesions on the rat's r eaction to a c at. Journal of Comparative and Physiological Psychology, 1972. 78: p. 77-82. [36] Gonyea, W., Ada ptive differences in t he b ody proportions of l arge felids. Acta Anatomica, 1976. 96: p. 81-96. [37] Caro, T., Cheetah mothers' v igilance: looking out for p rey or fo r predators? Behavioural Ecology and Sociobiology, 1987. 20: p. 351-361. [38] Eaton, R., Hunti ng b ehaviour of the cheetah. The Journal of Wildlife Management, 1970. 34: p. 56-67.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

45

[39] Cabanac, M., Exertion and pleasure from an evolutionary perspective, in Psychobiology of Physical Activity E.A.P. Ekk ekakis, Ed itor. 2 006, Human Kinetics: Champaign IL. p. 79-89. [40] Borg, G., Psychophysiological bases of perceived exertion. Medicine & Science in Sports & Exercise, 1982. 14: p. 377-387. [41] Ekkekakis, P ., Let them r oam f ree? Physiological and psychological evidence f or the potential of self- selected exe rcise i ntensity in pu blic health. Sports Medicine, 2009. 39: p. 857-888. [42] Thayer, R., e t a l., W alking more e ach day elev ates mood, es pecially energy, a cen tral m ood element, in 16th Annual Convention of the American Psychological Society. 2004: Chicago. [43] Polman, R., M. Kai seler, a nd E. B orkoles, Ef fect of a singl e bout o f exercise on t he mo od of p regnant women. Journal of Sport Medicine and Physical Fitness, 2007. 47: p. 103-111. [44] Deci, E. a nd R. Ry an, I ntrinsic mot ivation an d s elf-determination in human behaviour. 1985, New York: Plenum. [45] Nicholls, J., The competiti ve et hos and dem ocratic education. 19 89, Cambridge, MA: Harvard University Press. [46] Nicholls, J., Conceptions of abi lity and achievement m otivation, in Research on m otivation in education: Student motivation R.A.C. Ames, Editor. 1984, Academic Press: New York. [47] White, S. and J. D uda, The relationship o f g ender, level of s port involvement, and p articipation motivation t o t ask and ego or ientation. International Journal of Sport Psychology, 1994. 25: p. 4-18. [48] Gernigon, C., et al., A dynamic system perspective on goal involvement states i n sport. Journal of Sport & Exercise Psychology, 2004. 26 : p. 572-596. [49] Treasure, D. and G. Rob erts, Relationship between female adolescents’ achievement goa l orientations, perceptions of t he m otivational climate, belief about su ccess and so urces of satisfact ion in b asketball. International Journal of Sport Psychology, 1998. 29: p. 211-230. [50] Bandura, A., Self-efficacy: the exercise of control. 1997, San Francisco: Freeman. [51] Moritz, S ., et al., The relatio n of self-efficacy meas ures t o s ports performance: A m eta-analytic review. Research Quarterly for Exercise and Sport, 2000. 71: p. 280-294. [52] George, T . and D . Feltz, M otivation in sport from a collective efficacy perspective. International Journal of Sport Psychology, 1995. 26: p. 98116.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

46

Andrew Edwards and Remco Polman

[53] Spielberger, C. , Theor y and r esearch on a nxiety, in Anxi ety a nd behaviour. Spielberger, Editor. 1966, A cademic Press: New York. p. 320. [54] Gould, D., C. Gr eenleaf, a nd V. Krane, Ar ousal-anxiety and sport, in Advances in s port psy chology. 2002, Human Kinetics: Champaign, IL. p. 207-241. [55] Moran, A., Sp ort and exercise psychology: a cr itical introduction. 2004, London: Psychology Press. [56] Scanlan, T. and M. Passer, Factors related to competitive stress among male y outh sport participants. Medicine & Science in Sports, 1978. 10: p. 103-108. [57] Vealey, R. and M. Chase, Self-confidence in sport, in Advances in sport psychology, T. Horn, Editor. 2008, Human Kinetics: Champaign, IL. [58] Gould, D., K. Dieffenback, and A. Moffett, Psychological characteristics and their development in O lympic champions. Journal of Applied Sport Psychology, 2002. 14: p. 172-204. [59] Gould, D., et al., A survey of U.S. Olympic coaches; variables perceived to hav e in fluenced athlete per formance an d coach ef fectiveness. Sport Psychologist, 2002. 16: p. 229-250. [60] Woodman, T. an d L. Har dy, The r elative impa ct of c ognitive a nxiety and self-confidence upon sport performance: a meta-analysis. Journal of Sports Sciences, 2003. 21: p. 443-457. [61] Parkinson, B., et a l., Changing mo ods: th e psychology of m ood an d mood regulation. 1996, London: Longman. [62] Lane, A., C. Be etie, an d M. Stevens, Moo d matte rs: a re sponse to Mellalieu. Journal of Applied Sport Psychology, 2005. 17: p. 319-325. [63] Beedie, C., P. Te rry, a nd A. Lane, The p rofile o f mood st ates a nd athletic pe rformance: t wo meta-analyses. Journal of Applied Sport Psychology, 2000. 12: p. 49-68. [64] Bird, A. and A. Horn, Cogn itive a nxiety and men tal er rors in sport. Journal of Sport & Exercise Psychology, 1990. 12: p. 211-216. [65] Abernethy, B., Attention, in Handbook of sport psychology H.A.H. R.N. Singer, & C.M. Janelle Editor. 2001, John Wiley: New York. [66] Frijda, N ., T he emotions. 1 986, C ambridge: Cambridge University Press. [67] St Clair Gibson, A., et al., The conscious perception of the sensation of fatigue. Sports Medicine, 2003. 33: p. 167-176.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Introduction to Pacing in Sport and Exercise

47

[68] Micklewright, D., et al., P revious experience inf luences p acing during 20 km time trial cycling. British Journal of Sports Medicine, 2010. 44: p. 952-960. [69] Foster, C., et al., Physiological responses during simulated competition. Medicine & Science in Sports & Exercise, 1993. 25: p. 877-882. [70] Noakes, T., M. Lambert, and R. Hauman, Which lap is the slowest? An analysis of 32 world mile record performances. British Journal of Sports Medicine, 2009. 43: p. 760-764. [71] Tucker, R., M. Lambert, and T. Noakes, An analysis of pacing strategies during men’s world-record performances in track athletics. International Journal of Sports Physiology and Performance, 2006. 1: p. 233-245. [72] Macdermid, P . and A. Edwar ds, Influence of cr ank length o n c ycle ergometry per formance o f well-trained f emale cross-country mountai n bike at hletes. European Journal of Applied Physiology, 20 10. 10 8: p . 177-182. [73] Ingen-Schenau, G. J.D. Konin g, and G . Groo t, The distribution of anaerobic ener gy in 10 00 an d 400 0 metre cycling bouts. International Journal of Sports Medicine, 1992. 13: p. 447-451. [74] Abbiss, C. an d P. Laursen, Models to explain fatigue during prolon ged endurance cycling. Sports Medicine, 2005. 35(10): p. 865-898. [75] Garland, S., An a nalysis o f the pacing st rategy ado pted b y e lite competitors in 2000 m rowing. British Journal of Sports Medicine, 2005. 39: p. 39-42. [76] Davies, C. and M. Thompson, Aerobic performance of female marathon and mal e ultr amarathon athl etes. European Journal of Applied Physiology, 1979. 41: p. 233-245. [77] Billat, V., et al., Effect of free versus constant pace on performance and oxygen kinetic s in running. Medicine & Science in Sports & Exercise, 2001. 33: p. 2082-2088. [78] Koning, J.d., M . Bo bbert, and C. Foster, Determination of op timal pacing s trategy in track cy cling with an ene rgy flow model. Journal of Science and Medicine in Sport, 1999. 2: p. 266-277. [79] Thompson, K., et al., The effect of even, positive and negative pacing on metabolic, kinematic and tem poral v ariables durin g breaststroke swimming. European Journal of Applied Physiology, 2003. 88: p. 438443. [80] Liedl, M., D . Swa in, an d D. B ranch, P hysiological effects of c onstant versus variable power during endurance cycling. Medicine & Science in Sports & Exercise, 1999. 31: p. 1472.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

48

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[81] Edwards, A. and T. Noakes, De hydration: cause o f fatigu e o r si gn o f pacing in elite soccer? Sports Medicine, 2009. 39: p. 1-13.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Chapter 3

LIMITATIONS TO PHYSICAL PERFORMANCE

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

3.1. ABSTRACT The aim of t his chapter is to investigate th e circumstances and potential ca uses o f performance li mitations in r esponse to exercise. Traditional th eories have t ended to pr esent p olar pers pectives on this issue such as central (nervous system) vs. peripheral (muscle) limitations. However, neither hypothesis explains the occurrence of fatigue across all situations leading to the suggestion that an integrative control system may be in fluential. Diff erent pe rspectives and interpretative models are discussed in this chapter and a new psychophysiological model presented, in whic h the conscio us ( aware and sub aware) brain r egulates performance b ased on aff erent sensor y information received and vi a efferent instructions for muscle recruitment.

3.2. INTRODUCTION Human performance is limited [1, 2]. It is not possible to endlessly sustain high i ntensity physical wor k as th is is usua lly accompanied by increased severity of unpleasant physical sensations such as localised pain, nausea, and heat s tress [ 3]. W hile th ere may b e no argument that l imits exist to w hich humans can perform p hysical tasks, th e caus es of s uch limitations rem ain fervently disputed [4]. The inability t o voluntarily prev ent a decline in work ou tput despite o ur best efforts is generally referred to as fatigue [5]. Many complex physiological and psychological factors contribute to performance limitation and this chapter

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

50

Andrew Edwards and Remco Polman

will consider these. However, it should be clear; th e search for a single factor which ca uses fatigue an d t hus lim its performance c ould be considered analogous to the search for the source of the Nile [6].

3.3. THE NERVOUS SYSTEM

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

The n ervous system in fluences all phy siological activity an d is in many ways akin to a sop histicated computer network. In this system, the br ain acts as th e h ub, int egrating all se nsory i nformation rec eived ( via afferent pathways), se lecting an appropriate resp onse an d then provid ing th e motor stimulus (v ia efferent p athways) to i nitiate the process of voluntary m uscle recruitment and su bsequent p hysical ac tion. Thi s r equires i ntegrative communication and coordination between different regions of the brain, body and physiological systems [7] (Figure 3.1). Such conscious r egulation occurs in the c erebral cortex as a c onsequence o f e ither plan ned thought, or automaticity if t he response is s o fa miliar as to not w arrant s ignificant attention [8-10].

Figure 3.1. Brain regulation of human movement in response to afferent and efferent signals. Taken with permission [24].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

51

The structural components of the brain that are most directly involved in control of mov ement a re the ce rebrum, diencephalon, cerebellum and brainstem (e .g [11 ]). Th e c erebrum co nsists of tw o hal ves (right and le ft hemispheres) which are connected by a sheet o f n erve fib res kno wn a s th e corpus callos um. Bo th hemisp heres are co vered by an undulat ing, wr inkly, gray coloured surface called the cerebral cortex. This covering of thin tissue of nerve cell bo dies has b een r eferred to as th e s ite of the conscious mind and intellect [12]. The fr ontal l obe of the c erebral cortex is the ar ea anterior to t he c entral sulcus (central l ateral groove of the brain) an d contains areas v ital to th e control of v oluntary m ovement. Th e frontal lobe is invo lved in plann ing actions and mov ement, as well as abstract thought. This region of the cerebral cortex also hosts the primary motor cortex which contains motor neurons that send im pulses t o specific sk eletal muscles th roughout th e body [9]. The parietal lobe is the area immediately posterior to the central sulcus and is the brain region primarily involved in the perception of sensory feedback. Specific types of s ensory inf ormation are su bsequently trans mitted fro m the pa rietal region of the cortex vi a sensory ner ves t o the relevant ar eas of t he br ain for further processing. Inter-communication between cortical regions is crucial for the execution of voluntary movement [13]. The cerebral cortex is commonly desc ribed as comprising thr ee ma in parts: sensory, motor, and association areas [9, 11]. The sensory areas are the regions that r eceive and p rocess inpu ts fr om the th alamus and are call ed primary sens ory ar eas. The sup plementary motor ar eas an d pr emotor c ortex which se lect voluntary movements (a ssociation areas) l ie ant erior t o the primary mo tor cor tex. I t is the primary motor c ortex that e xecutes voluntary movements in response to inputs from the motor association areas. Subcortical b rain regions also p lay i mportant roles in the con trol of movement as for exa mple the deep ly ing b asal g anglia, recei ving b oth descending information from the motor cortex and ascending information from the brainstem. This small region of nuclei is involved in the control of force, and initiation of movement [14]. The di encephalon contains the thalamus and hypothalamus and is a further deep region of the brain which lies between the cerebrum and the brainstem. The th alamus pr imarily ac ts as a r elay c entre, receiving an d integrating m ost sens ory inputs from the s pinal cor d and brainstem to high er brain regions (e.g. t he cerebral cortex) f or c ognitive processing. The thalamus also plays an important role in th e control of mood, attention, and the perception of pain [10]. The hypothalamus lies im mediately beneath t he thalamus and is the brain r egion for the co ntrol of t he endocrine

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

52

Andrew Edwards and Remco Polman

system, r egulation of ho meostasis, body tem perature, hu nger, thirst and physiological responses to stress. Located dir ectly u nder the cerebral hem ispheres and c onnected to the spinal cor d, the br ainstem cont ains thr ee mai n ar eas th at ar e in volved i n involuntary human movement [9]. The p ons is located at the top of the brain stem and acts as a bridge between the cerebral cortex and cerebellum. Various neural pathways either pass through the pons from the cortex on their way to the spinal cord or terminate as they come from the cortex. The pons region is involved in fu nctions s uch as chewing, s wallowing, s alivating and b reathing. The second area, t he medulla [oblongata] is primarily an extension of t he spinal cord a nd se rves as a re gulatory re gion for v arious auton omic physiologic processes such as respiration. Although it appears ever ything starts an d stop s with the b rain, there ar e specific r eflex c ases wh ere phy sical action precedes br ain activity. F or example, wh en an impuls e resulting fr om sensory stimul ation of the skin is transmitted via sensory ner ves to the spina l cor d, i t ca n tr igger a loc al (immediate) reflex at that level, prior to travelling to t he br ain [1 1]. Such ‘spinal’ r eflexes ar e immediate r esponses whi ch a ct in a pr otective role. A common example is the withdrawal r eflex. Th is ma y oc cur whe n a person touches a h ot o bject and withdraws their hand fro m the h ot o bject wi thout thinking about it. Th is occurs as the heat s timulates tem perature and p ain receptors in the skin, trig gering a sensory nerve impul se th at trav els to the spine. The s ensory neur on then synapses with i nterneurons in the sp ine tha t connect to motor neurons. Some of these neurons send motor impulses directly to the f lexor muscles o f t he ar m to al low with drawal; o ther motor neurons send inhibito ry im pulses to th e ex tensor muscl es so fl exion is not inh ibited (reciprocal in nervation). This split-second action is ev oked prior t o brain involvement. Concu rrently, interneurons r elay the sensory i nformation up to the brain so that the person becomes aware of the pain, what has occurred and will adopt a conscious behaviour (i.e. to stay away from the heat) so not repeat the action. As th e level of control moves from sp inal cor d to the m otor c ortex, the degree o f possible movement complexity increases from simple reflex action to highly complicated movements. Thus, it is likely that all non-reflex exercise situations should be co nsidered subject to neural regulation [15]. In summary, motor (neural) dr ive evokes muscular ac tion and is t he f inal r esult of communication between brain centres, collectively acting on the motor cortex. This process describes how sensory information stimulates a motor response.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

53

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

3.4. LIMITATIONS: CENTRAL AND PERIPHERAL OBSERVATIONS This section w ill e xamine the c oncepts a nd pe rspectives of performance limitation fr om central an d per ipheral ne uromuscular control perspectives. Both mechanisms bro adly predict the same ou tcome wher eby reduced force generating capacity of the muscle is experienced, albeit with a different cause. Peripheral fatigue has been defined a s the loss of fo rce ca used by processes occurr ing at or dis tal to the neuromuscular junction [1 6]. It is generally cons idered as f atigue o ccurring within the muscle. Conversely, central f atigue is ass ociated with i nstances wh ere th e central n ervous sy stem has a diminished n eural (b rain) drive to muscle [15 ]. I f so me loss of f orce occurs because of the failure of the central nervous system to maximally drive the muscle, it is known as central fatigue [16]. The debate is therefore broadly one of control mechanisms either within the central nervous system (brain and spine - central) or anywhere outside the central nervous system (e.g. muscle – peripheral) a s the sour ce o f di minished force ou tput/performance ( fatigue) [17]. The common model us ed to describe the pr ocess a nd ca use o f f atigue among exercise phy siologists h as been the per ipheral ( muscle) expl anation [18]. The gen eral acceptance o f t his interpretation may be largely due t o the early observations of Mer ton [17]. Merton addressed t he i ssue of central vs. peripheral m echanisms by i nducing fatigue in a muscle group in response to maximal voluntary contraction (MVC). He had th e novel idea to additionally innervate the active mus cles dur ing th e MVC wi th localized e lectrical stimulation utilising an interpolated twitch technique. Merton reas oned it was po ssible to dis tinguish bet ween fatig ue components der ived from the con tracting muscle (peripheral f atigue) an d components within the central nervous system (central fatigue). For example, an i ncrease i n muscle t ension durin g MVC wi th the addition of electrical stimulation w ould su pport a ce ntral fati gue hypothesis (i. e. that greater stimulation fr om the b rain could in crease m uscle tension and fo rce). The production of greater force with stimulation would demonstrate that sustained maximal v oluntary contract ions do not r esult in the recruitment of all motor units, des pite sustained maximal effort. Co nversely, if muscle tension and force did n ot incr ease a s a con sequence of a dditional el ectrical s timulation, this would indicate a peripheral (muscle) source of fatigue. In Merton’s study, a series of twitches evoked by stimulation of the ulner nerve did not alter the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

54

Andrew Edwards and Remco Polman

fatigue pattern and consequently he logically concluded that the site of fatigue must have been within the muscle fibres.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

“Fatigue is p eripheral, for when strength fai ls, electrical stimulation of the motor nerve cannot restore it.” [17].

The study of Merton [17] pr ovided co mpelling evidence for th e pr imary role o f peripheral (muscle) mechanisms in the l imitation of maxi mal h uman performance. Nevertheless, it is possible that this classic study also influenced many scientists to aut omatically adhere t o a model which is always peripheral in nature [19]. The t witch in terpolation technique u sed by Merton is s till utilised i n modern investigations, but it is i nteresting to note that these s tudies have not confirmed the original findings of Merton that motor units are fully recruited and d ischarged at the onset of MVC. In c ontrast, it seems c onsistent t hat voluntary action recr uits 8 5-90% of motor units during M VC [20 ]. Thus, further motor units seem to be k ept i n r eserve for p ossible us e i n ins tances such as a final spurt of force if r equired in a r ace. An e xtreme example of the influence of ce ntral (stimulation) f actors occurs when a task cannot b e continued (task failure) bu t the muscles could still produce the required force when stimulated electrically [19]. The debat e between central and peripheral me chanisms was r eignited following Merto n’s wo rk, wh en Biglan d Ritchie [21] proposed th ree m ain regions as s ites of f atigue 1) t hose wh ich l ie in the cen tral n ervous s ystem (neural drive), 2) those concerned with the transmission from central nervous system to muscle, and 3) those within the indi vidual m uscle fibr es. Nevertheless, alt hough this study provided a welcome re-ex amination of fatigue it did not identify a primary site for limitation: “A major q uestion y et to be answered i s whi ch of the se ev ents determine performance and which are si mply inci dental by- products.” [21].

Evidence fro m various subsequent res earch studies s uggests f unctional changes occur at each of the sites proposed by Bigland Ritchie [21, 22] an d it is po ssible that they m ay work synergistically du ring exer cise to control human p erformance [ 23]. However, a n important sh ared characteristic of a ll central and per ipheral fatigue models is th e de termination of researchers to search for a single site of catastrophic (limiting) system failure. In each model, individually nom inated sites have been p roposed as a sou rce of per formance

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

55

limitation either central ly or p eripherally. I n th is regard all models s hare t he common goal of s earching for a site ( e.g. per haps se eking the sour ce of the Nile) [ 6]. The same s tudy in which n umerous ( central and peripheral) causal sites were proposed [21] contains two interesting passages:

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

1) ‘Everyone has ex perienced th e sensations of fatigue an d the increasing difficulty of continuing a given level of physical exercise.’ 2) ‘…much evidence sug gests that th e physiological even ts underlying fatigue co mmence at th e on set of activit y, although th ey cannot always be readily detected.’ [21] The central nervous system plays a crucial role in the m aintenance of the steady state of the internal environment (homeostasis) [24]. The motor cortex of th e brai n is responsib le for t he generation of th e motor d rive a nd recruitment of mot or units dur ing e xercise [ 25]. We are co nscious of this motor drive, but we are unaware of the co ncomitant motor control of muscles regulating our posture during exercise [5]. Furthermore, the brain is the centre of c ognition an d r ecognition of phy sical s ensations experienced a s fat igue develops. Sens ations o f fatig ue ca used by ex ercise are comm on and du ring exercise the work load may create such an intense sensation that it is perceived necessary to reduce force so to su ccessfully complete the bout (pace), or even cease exercise if t he se nsations are too severe [ 3]. The s ensations of f atigue and exh austion may b e co nsidered p sychological en tities, w hich induce changes in b ehaviour. The phy sical and biochemical changes during exercise are physiological entities. When taken together as both being of importance in our ability to sustain exercise intensity, complete work as required, or simply successfully pace ourselves, it is perhaps useful to consider the possibility of integrated ph ysiological an d psychological mod els (psychophysiological) in which catastrophic system failure does not occur.

3.5. LIMITATIONS: CARDIOVASCULAR REGULATION The cardiovascular system comprises t he heart ( pump), hi gh pressure blood vessels (for distribution of arterial blood) and a low pressure collection and r eturn system (ven ous blood return ed to the h eart and lun gs). For many years, it has been widely considered that it is this system which regulates and limits sus tained exercise [ 1, 26] . F rom this p erspective, the cardiovascular system restricts performance via exercise induced deficiencies to the delivery

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

56

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

of b lood, nutrients and oxygen to the working muscles, by local muscle utilisation pr ocesses for the r e-generation of ATP ( energy cur rency), an d by limitations t o (pulmonary) blood ci rculation w ith t he lungs f or gas exchange [1, 18]. Cardiovascular limitation to physical performance is usually described by the cardiovascular/anaerobic model [27] (Figure 3.2). P rofessor Tim Noakes has previously identified several flaws with this model [2], such that it predicts fatigue develops as a consequence of the heart no longer being able to supply oxygen nor is the cardiovascular system able to remove waste products from the wo rking muscles. Ac cording to th is de finition, limitations to 1) t he pumping capabilities of the he art, 2) th e density of capillaries sup plying skeletal mu scle wi th oxygenated blood an d 3) the quantity of mit ochondria with which to extract oxygen could all directly restrict performance.

Figure 3.2. Mechanism of fatigue according to AV Hill’s (Cardiovascular/Anaerobic) Model of Exercise Physiology. Taken from Noakes [74] with permission.

Numerous studies have co nfirmed maximal car diac output improves as a consequence of t raining-induced changes to strok e volume [ 28]. Cap illary density is also enhanced f ollowing tr aining prov iding greater quantities of oxygenated blood to muscle, and mitochondrial density has also been reported to improve as a consequence of dedicated endurance training [18, 29]. These adaptations either singularly or collectively work to delay the onset of skeletal muscle ana erobiosis at exercise int ensities above the anaerobic th reshold, thereby r educing bl ood lactate c oncentrations in muscle and b lood [ 27]. I n a

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

57

highly trained state, the delayed onset of blood lactate accumulation allows the exercising muscles t o c ontinue contracting for longe r at hig her intensities before the onset of fatigue and th e eventual d evelopment of e xhaustion. According to th is mod el, exer cise must cease as it i s pr ogressively d riven towards the p oint of p hysical exhaustion, when p hysiological s ystem f ailure occurs. Variations to th e cardiosvascular/anaerobic mo del have been pr oposed to incorporate f actors suc h as energy supply and energy depletion (see [2] fo r review). Brie fly, in the energy supply model, fatigue d uring high in tensity exercise has been s uggested to occur as a consequence of t he inability to supply adenosine triphosphate (ATP) at rates su fficiently fast to sus tain exercise [ 26]. I n that model, tr aining a nd di etary ind uced increases to ( e.g. glycogen) storage capacity and improved ability to utilize metabolic substrates during exercise may provide a greater capab ility to produce ATP (i.e. supply energy). The r elated energy depletion m odel is largely specific to endurance exercise s ituations l asting in excess of two hours. I n th at variation of t he cardiovascular/anaerobic m odel, it has been a rgued that e ndogenous carbohydrate stores is a limiting (depleting) factor [ 26]. This is probably due to t he ob servation that f atigue in pr olonged exercise is asso ciated with significant r eductions in liver and muscle glycogen [ 18, 30 ]. In addition, correction of ex ercise-induced hypoglycaemia e nables e xercise to b e continued [3 0] w hile s upplementary c arbohydrate i ngestion du ring e xercise appears to dela y or slow the p rogression of fatigue [31]. Nevertheless neither energy supply and energy depletion models have un iversally received acceptance. F or example, in the energy supply mod el, ex ercise oug ht to terminate when muscle ATP depletion occurs; however, that is only the case when muscle rig or de velops (i.e . po st death). ATP c oncentrations, e ven in muscles f orced to contract u nder isch aemic conditions, d o no t d rop b elow ~ 60% of resting values [18 ]. In th e energy depletion mod el, pre-exercise carbohydrate l oading o ught to produce a n ergogenic effect but t his is not consistently the c ase [ 32]. Als o, a lthough car bohydrate supplementation may improve ex ercise outco mes in so me cases, studies have also sh own that post (endurance) exe rcise c oncentrations of m uscle gl ycogen a re sim ilar between normal and supplementation conditions. Th is sugges ts that carbohydrate may be u seful to exercise performance (i.e. t he tr ajectory of per formance may be different, b ut bot h ar e managed towards the sa me minimal r eserve of glycogen) [31], it is still likely to b e r egulated and managed by a central (brain) p rocess t o avoid total depletio n of muscle glycogen [3 3, 34 ]. The

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

58

Andrew Edwards and Remco Polman

cardiovascular/anaerobic model an d its variations h as b een the prevalent model in exercise physiology.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

3.6. LIMITATIONS: BRAIN REGULATION The cardiovascular/anaerobic model has r eceived con siderable criticism in recent y ears [ 2, 3, 15, 3 5] as it does not explain t he occurrence of fatigue across all situations where it would be expected [36]. That model ignores the role of neu ral c ontrol over a ll physiological s ystems. Regulatory c ommand from t he br ain op erates both d uring th e pre ex ercise anticipatory period and also i n response to e xercise wher e motor cor tex s timulation of the medulla (brainstem) oscillates in accordance with the size of the muscle mass required to b e act ivated d uring ex ercise. S ince the co nscious br ain e xpresses a voluntary desire (impulse) to the mot or cortex t o initi ate and continually regulate m uscle recruitment d uring ex ercise [9], it is surprising that brain regulation of performance is considered a contentious or new concept. Examples of neural regulation of performance can easily be discerned in hot co nditions, wh ere at hletes are well known to self-regulate (pa ce) performance from the initial stages of the bout [37, 38], well in advance of the failure of heat dissipation mechanisms such as sweating [39]. According to the traditional cardiovascular/anaerobic model, fatigue shou ld be a gradual involuntary process o f a decli ning force generating capacity of m uscle as it approaches depletion of a sub strate or other phy siological factor [1, 26 ]. Fatigue wou ld th erefore b e cons equent to a failing physiological sy stem. Eventually the sy stem w ould fail (a dep leted/empty state) at wh ich ti me t he individual is no longer fatiguing, but exhausted. However, this p erspective is not compatible with sport or exercise observations in which athletes are free to choose ho w to pace th emselves. Ath letes display behav iour similar to o ur animal counter parts and p ace in acco rdance to the environ ment and th e demands o f th e task [40 ]. Th e consequence o f th is behaviour is a v oluntary redistribution o f effort when tired so to a void ex cessive fatigu e sensations [15]. This action is adopted in response to continual and progressively stronger afferent sensations (signals) received by the brain [7]. It is a sensory feedback system which becomes more intense and persuasive if the intensity of exercise continues to increase towards its endpoint. The decision to either slow down or cease exercise therefore pr ecedes the de velopment of phy siological sy stem failure. The ca rdiovascular system provides powerful afferent feedback to the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

59

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

brain which infor ms th e decision to slow do wn or cease exercise, but is unlikely to directly limit performance. Further evidence for the presence of a behavioural mechanism controlling physical performance is pr esent in both 1 ) tests of maximal aero bic power ( V⋅ O2 max) and 2) during exercise performed at moderate to high altitude [3]. In re sponse to V⋅ O2 max testing, the cardiovascular/anaerobic m odel predicts that i ndividuals will reach a maxi mal le vel of oxy gen uptake at w hich p oint oxygen uptake will plateau as the cardiovascular system reaches capacity. The observation of a plateau in oxygen uptake has been a central tenet of V⋅ O2 max testing for many years and yet ~60% of individuals undertaking this test show no sign of attaining such a plateau [41]. A substantial proportion of individuals reach a maximal level of tolerable discomfort at wh ich point they voluntarily decide t o cease exercise without exhibiting a plateau in V⋅ O2. Thi s qu estions whether m aximal performance i s truly e xperienced, o r s imply whether a maximal le vel of to lerable di scomfort (or e ffort) is r eached i n advance o f physiological system capacity. I f mor e muscle w ere able t o be voluntarily recruited at maximal effort, more oxygen would be consumed and V⋅ O2 would continue to increase. The V⋅ O2 max should perhaps more correctly be labelled the ‘maximum of voluntary effort’ (Figure 3.3).

⋅

Figure 3.3. Example of oxygen uptake ( V O2) responses to two maximal incremental ⋅ exercise challenges. The dotted line represents a progressive increase in V O2 towards a maximal (peak) value without evidence of a plateau. The solid line represents a similar maximal value but with evidence of a plateau due to brain-imposed regulation of further motor units in the active muscles. Each are examples of maximal voluntary performance, restricted by the limits of tolerable discomfort.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

60

Andrew Edwards and Remco Polman

At moderate to high altitude, physiological responses to exercise have also been cited as clear c ontrary evide nce t o th e c ardiovascular/anaerobic model [41]. For example, the reductions of O2 partial pressure at altitudes above sea level inevitably restrict the amount of O2 that can be taken up by muscles and used to provide aerobic energy. This should mean exercise will require greater anaerobically sourced ener gy at an earlier stage than experienced at sea level due to the reduced av ailability of O 2. As a co nsequence, co ntinuation of exercise would have to be powered to a greater extent by anaerobic energy in which la ctic a cid is a by-product. The fact that m aximal blood la ctate at altitude rem ains either unchan ged or, more f requently, is lower t han at sea level has been termed the lactate paradox [42]. Importantly for the cardiovascular/anaerobic, energy supply, and energy depletion models, ea ch predic ts p hysiological sy stem fai lure at the poi nt o f physical exhaustion. In all cases, fatigue is a developing feature in the gradual progression to wards a final ( terminal) ex haustion (e.g. running to em pty) where it is a physical imperative to immediately cease exercise. However, as skeletal muscle is n ever f ully r ecruited during e xercise, muscle ATP never falls b elow 60% of r esting lev els, gly cogen con centration d eclines but is not depleted during exercise [34], and fatigue in many circumstances occurs prior to high concentrations of metabolites such as lactate and hydrogen ions [2]. In 1996, Ulmer proposed that exercise performance might be regulated by a control centre located somewhere in the central nervous system [43]. In this model, it was sugg ested alte rations i n exercise i ntensity we re continuously regulated by a feedback system where afferent information (such as muscular metabolism or for ce) ar e received by th e central c ontroller v ia afferent pathways. The controller would th en be ab le to us e this infor mation from the muscles, as well as f eedback fro m o ther organ s to optimise and regulate performance. Professor Tim Noakes and his group have sin ce expanded Ulmer’s theory by sugg esting tha t central skeleta l muscle activation i s co ntrolled by a regulator, probably located in the brain which acts to protect vital organs from injury or da mage [15 ]. This sy stem has been termed the central governor model of metabolic control [3, 44 ]. It is proposed in this model th at exercise performance is continuously man ipulated in r esponse to the interaction of numerous physiological systems monitored by a central controller via constant feedforward and feedback loops between peripheral systems and the br ain [7]. In this system, the endpoint of the bout represents a known variable by which the central governor continually manipulates pace [45, 46] (Figure 3.4). In this sense, t he brain controls ( and os cillates) motor uni t recruitment s o th at th e

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

61

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

athlete can complete th e known duration o f the task without ex periencing intolerable physical dis comfort wh ich might ne cessitate i mmediate ces sation of e xercise. In this model, f atigue is a s ubconscious p rocess, representing an underlying n eural inte grative p rocess [1 5, 2 4, 47]. Therefore, according to Noakes an d co-workers the central controller s ubconsciously osc illates and regulates muscle rec ruitment so to avo id unsu stainable and, eve ntually, intolerable conscious physical sensations [45, 46].

Figure 3.4. Brain regulation of performance based on feedback (afferent) signals from different physiological systems and feedforward (efferent) signals to muscle. Regulation by the brain is in accordance with the willingness to tolerate discomfort across the exercise bout in knowledge of the known demands of the task, prior experience, and motivation. Taken with permission from Noakes [41].

An interesting recent pers pective to the brain r egulation model was proposed b y M arcora who, w hile a ppearing to accept the bra in regulates muscle recruitment and limits performance, also questioned whether there is a need for a central regulatory governor [48]. This perspectiv e suggests that the search for a central governor in the subconscious brain could be similar to that currently pursued by reductionists searching for a singular cause of fatigue. Another simpler perspective which we propose, is that the conscious brain is t he central governor. A single n eural ( controller) region wh ich regulates

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

62

Andrew Edwards and Remco Polman

exercise performance within the subconscious is mos t unlikely as the br ain is the su mmation of a v ast neural n etwork a nd e ach r egion is tasked w ith contributory fun ctions t owards over all sy stem ( brain) oper ation. Mill ions of nuclei ensu re inter-region neural co mmunication wi thin t he circui try of the brain without the need for a s ingle ‘master’ or ‘governor’, other than perhaps regulation by our consciousness. In many ways the idea of a single intelligent regulatory go vernor w ithin th e subconscious mind is ak in to the homunculus theory of a ‘little man’ operating the body from within the brain [49]. Clearly such a co ncept wo uld al so require the homunculus to have decision m aking intelligence; however; t his would re quire conscious awar eness wi thin the subconscious brain. Therefore the homunculus would require a homunculus of its own (and so on). After all, a b ird is capable o f tho ught an d cons cious awareness [ 50], yet does no t poss ess a neocortex (outer lay er of th e cer ebral cortex) where t houghts occur i n the mammalian brain. Neural circuitry adapts among our avian contemporaries to counteract this anatomical omission and so still facilitates conscious thought. Admittedly, the avian brain is not capable of sophisticated thou ght processes, but co nscious behavioural decis ions such as seeking sh ade in hot weather are not beyond the average bird. I t might therefore mak e gr eater pr actical s ense t o c onsider the brain as a complex system of neural communications, regulated by consciousness. It i s well known that sensor y (afferent) in formation is re ceived by the thalamus [10] a nd comm unicated to the pri mary sensory cortex wi thin th e parietal lobe. Visu al information is pr ocessed in the occ ipital l obes ( visual cortex) a nd temporal l obes pr ocess auditory information (auditory cortex). These sources of information interact with considerations such as planning and problem s olving ( prefrontal regions of the cerebral cortex). Addition ally, the cerebellum provides coordinative information while deep brain regions such as the hippocampus process memories of past experiences and nuclei within the hypothalamus receive and pass on important infor mation from the brainstem such as body temperature, hunger, and thirst [9]. These factors all interact, and collectively act upon t he motor cortex to s timulate v oluntary muscle recruitment. Nevertheless, th is does not explain how we slow down, or speed up during exercise without consciously deciding to do so. Hence, this leads to the current search for an unlikely regulatory control centre in the subconscious brain [15]. We propose that it is possible to alternatively explain neural regulation of exercise p erformance by re-examining t he way in which th e subconscious brain is i nterpreted. F or exa mple, if the s ubconsciousness is c onsidered as a state o f ‘sub awareness’ w ithin a conscious s tate [ 12], then the pot ential for

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

63

neural regulatory c ontrol bec omes more com pelling. The subc onscious logically oper ates to keep the brain active whi le i n either a state of r est ( i.e. sleeping) or f or au tomating processes which r equire s keletal muscle activity but ar e considered s o r outine as to not r equire our c onscious awareness. W e are capable of executing many physical tasks without dedicating much of our ‘aware’ consciousness to them (such as changing gear at the appropriate time in a car ) a nd these tasks all require motor unit recr uitment which is st ill regulated by the same n eural pr ocesses, but w ithout awar eness from the conscious mi nd [ 10]. As we bec ome more consciously aware of a n exercise situation it is usu ally consequent to sensory information bombarding the brain with increasingly negative cues such as developing sensations of thirst, nausea, and o ver heatin g [ 3, 51]. In the contin uance of hig h intensity exercise, th e severity of thes e sensory c ues eventually r eaches suc h int ensity as to tr igger conscious awareness. Until that time, such as at low levels of physical effort, regulatory control can be ac complished with mi nimal consc ious awar eness. This regulation would t herefore s till b e maintained by the c onscious br ain, albeit at a level of automated sub awareness (Figure 3.5). This pr ocess is no t merely lim ited by physiological sensations but could also be triggered by psychological str ess. Hence, o ne of t he characteristics of increased s tress is switching fro m an im plicit or sub awar e mode of task ex ecution to a consciously aware attempt to regulate behaviour [52]. Such an inter pretation o f br ain regulatory con trol rem ains largely consistent with the models proposed by Noakes [15] and also Marcora [48] but removes the requirement for a single intelligent, decision making homunculus in the s ubconscious brain . It i s therefore a regulatory process of the brain which operates at r elative levels of o ur conscious awareness. This is a subt le difference, but i t e xplains regulatory control of exer cise performance as a gross function of th e cerebral cor tex. Individual neur al a ctivities may predominate i n is olated brain r egions (e.g. p lanning within th e prefrontal cortex) bu t are not limited t o s pecific n eural site s. Reg ulatory afferent information is cons tantly passed to the thalamus fr om the peripheral ner vous system and upwards to different parts of the cerebral cortex for attention. It seems likely that while that regulatory information is within parameters considered to be of automaticity, it does not receive our significant conscious attention. Where acceptable l imits of automaticity (i.e. based on prio r experience or expectations of the task demands) are encroached, the stimulus gains intensity (e.g. increasing sensations of nausea, or developing a thirst) and thus reaches a level of awareness that requires significant attention and a gross behaviour. A behaviour (e.g. to take a drink) is therefore a gross response to a

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

64

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

developing st ate o f awareness a t a t ime of si gnificant need. This r esponse is less s ubtle than the minor manipulations a nd co ntrol of pe rformance that we make without significant awareness or apparent thought.

Figure 3.5. A comparison of brain regulation models of human movement. The Central Governor Model (A) and Psychological-Motivational Model (B) conceptualize the brain as comprising conscious and subconscious. The Conscious Brain Regulation model (Edwards and Polman) suggests the brain is continually in a conscious state, thus regulating muscle activation at different levels of awareness. At a low intensity of effort (minimal physical discomfort), the brain is able to regulate (oscillate) muscle activity via automaticity and minimal conscious awareness. As afferent sensations become increasingly severe, they reach conscious awareness thus requiring a less subtle (gross) behaviour to attend to the negative metabolic feedback.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

65

In situ ations where maximal effort is sustained t owards the end of an exercise bout an d yet p ower ou tput/force st ill declines, this r epresents a conscious desire to o verride the overwhelming sensations of f atigue, but also represents a voluntary failure to do so. At this point, conscious attention may be focused on achievin g t he best p ossible o utcome, but this des ire i s als o tempered by the realisation of the physical conse quences an d pr ojected (apprehensive) se nsations of sy stem failure . It is dif ficult to separate these considerations wh en determining maximal v oluntary eff ort. I n s ummary, the brain is t he sum of many par ts, each co mmunicating v ia c omplex neur al circuits. Therefore, maybe the question should not be where in the brain is the central governor? Perhaps the brain is the central governor.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

3.7. LIMITATIONS: PSYCHOLOGICAL CONSIDERATIONS Researchers have tried on many occasions to identify those psychological factors or skills w hich limit o r enhan ce athletic performance. The re i s some tentative evidence that the psy chological prof ile of successful athletes is different fr om t hose w ho ar e less s uccessful. Usi ng ques tionnaires ( e.g. Psychological Sk ill In ventory f or Sp ort [53]) to a ssess di fferences in psychological factors between athletes who have been more or less successful it h as b een fo und that s uccessful athletes ar e more s elf-confident, us e more imagery, are better in controlling levels of anxiety, prepare better mentally, use positive s elf-talk, se t clear go als, are more c ommitted, c ompetitive, and motivated to do w ell, and h ave better concentration or ar e better at refocussing (e.g. [54, 5 5]). Qualitative studies have suppo rted mo st o f these quantitative fin dings but have also uncovered a number of add itional psychological a ttributes. These in clude a positive atti tude, distraction control strategies, use of competitive s imulation, emphasis o n q uality rather than quantity of pr actice; pos t-competition evaluation a nd continual refinement o f their mental approach ( e.g. [56]). F ailure or poo r per formance has been associated with poor arousal control, negative thoughts, concerns about losing, not being able to concentrate, feeling listless and lack of coping [57, 58]. What seems clear is that psychological factors influence the way we behave in sport and exe rcise settings. Th ese psy chological fac tors ca n e nhance and h elp the way an athlete trains-competes or worsen and impede performance. Stress is an important factor which might limit athletic performance [59]. Although the sport psychology literature is awash with descriptions of sources of sport specific stressors few studies have reported pacing to be a stressor. For

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

66

Andrew Edwards and Remco Polman

example, in a recent study using concept maps, 18 stressors were identified by athletes f rom di fferent s ports and of different ac hievement levels [ 60]. Although keeping pace was not identified as a stressor, there were a number of stressors which were related to this including f itness, pe rformance and training. However, Lazar us [61] indicated th at s tressors are situation specific and th ere h ave b een d ifferences in th e str essors exp erienced by athl etes competing in different sports [62]. The demands of the sport or activity appear to influence t he ty pe o f s tressors experienced by at hletes or e xercisers. F or example, i n a study of in ternational cross-country runners, fat igue was th e most repo rted stre ssor (21. 4%) during training [63]. H owever, this wa s le ss important during co mpetition (3.6%). This is a common fin ding. That is, athletes t end to experience more, bu t le ss in tense s tressors, d uring tr aining than competition. This suggests that intervention should be tailored to both the training and competition context. The process by whic h an a thlete or exerciser at tempts t o reduce t he unpleasant feelings an d emotions fo llowing stress i s called coping [59]. It seems logical to assume that pacing is associated with coping. Hence, athletes need t o be a ble t o deal w ith th e p ain a nd n egative emotions associated with high intensity training load s. Adopting the s tress an d coping model proposed by Lazarus [59] it is important to distinguish a nu mber of phases. This model depicts stress and coping to be a dynamic process which involves transactions between environmental and personal variables. Primary appraisal refers to the process of as sessing t he impact of the event o n an individual’s p hysical and psychological w ell-being. An im portant di stinction is w hether an e vent i s perceived as a challenge/benefit or threat/loss. Hence, if a situation is perceived as a challenge or benefit the at hlete or exe rciser is li kely to experience le ss stress, ex perience positive emotions, and be more committed to achieve their goals. A thr eat/harm appraisal on th e ot her hand is likely to result in higher levels of stress, experience of negative emotions and failure to achieve goals [64]. Secondary appraisal involves t he assessment o f th e p ossible coping options to deal with the specific situation whilst trying to maximize gains and favourable outcomes and reducing harm [59]. This includes judgments of the resources available by the athlete or exerciser to deal with the event including coping strategies and perceptions of control over the event [65]. Following the appraisal process athletes will invoke coping strategies to deal with the stress. Having an extensive co ping repertoire will help athletes to cope more effectively with t he stress they experience and the e motions experienced. Hence, if co ping wa s succ essful then the i ndividual is li kely to experience

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

67

positive emotions, whereas a failure to cope effectively will result in negative emotions. The emotional state in turn will have a significant influence how the next stressful encounter is appraised. Coping a lways ta kes p lace within an em otional environment. It i s important to recognize th at the intensity a t which we exercis e influences th e emotions w e experience [ 66]. Hi gher l evels of ex ercise in tensity (a bove the anaerobic threshold) results in experiencing adverse or unpleasant emotions or a la ck or pl easurable em otions (r educed p leasure o r increased d ispleasure) whereas exercise intensities below the anaerobic threshold are associated with positive emotions. This suggests that the anaerobic threshold could perhaps be viewed as a pleasure/pain point (Figure 3.6). Consequently when exercising at high in tensities str ess exp erienced i s lik ely to be aug mented by the negative emotions i nduced by the ex ercise itself. This would requ ire the indi vidual to first utilize coping strategies which down regulate the negative emotional state which ar e s tressful in them selves. Also, the negat ive emotions can interfere with more active and adaptive ways of coping. Of course coping only refers to a str ategy used to deal wit h a s tressful encounter and does no t g uarantee a reduction in unpleasant emotions [67]. The ability to pace an exercise bout is an important skill. However, this is likely a very difficult thing to do for those about to e mbark on a new exercise programme and who have little experience in engagement in phy sical activity or exercise. This might be particularly the case for individuals who are obese or have chronic condition s which might make it more d ifficult to p ace themselves. Experience with di fferent e xercise regimes is therefore a n important variable which influences se lf-regulation of p acing. Although lack of e xperience app ears to be a n obv ious fac tor whi ch influences exercise behaviour the re ar e a lso differences in performance a t th e e lite level whi ch might to some extent be attributed to familiarity or learning factors. The ‘home advantage’ phenomenon s uggests th at teams and i ndividual a thletes at all levels are more likely to perform well and succeed on their ho me ground [68]. Although it is unclear what causes these dif ferences in per formance, it co uld be due to a number of factors such as learning, environmental familiarity, and critical psychological, physiological and behavioural states. Although the evidence is equivocal, another explanation for differences in selection of p acing s trategy in general and tolerance for e xercise intensity i n particular is per sonality. For e xample, ther e is eviden ce to suggest that extraverts perceive lower levels of RPE and better mood than introverts after a high in tensity exercis e bou t [ 69]. Ext raverts h ave al so bee n found to sh ow higher per sistence in a s tatic le g contr action task [ 70] a nd cycling against a

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

68

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

constant l oad tha n i ntroverts [ 71]. Extr aversion is also pos itively related t o exercise participation a nd a dherence. I n par ticular, ext raverts en gage in mor e demanding physical activ ities and are mo re likely to par ticipate in endurance sports requiring pacing skills, than introverts [72] .

Figure 3.6. Negative sensations such as metabolic acidosis develop in severity as exercise becomes progressively challenging. Exercise performed at low intensity or where the cost of the muscle action is metabolically minimal, could be considered pleasurable as the stimulus of outcome satisfaction outweighs physical discomfort. It is possible to conceptualize the anaerobic threshold therefore as a pleasure/pain threshold.

It ha s re cently been sugge sted [ 73] tha t prefe rence fo r e xercise a nd tolerance f or e xercise intensity are r elatively stable pr edispositions or traits which infl uence the ex ercise i ntensity an individ ual wil l select if g iven the freedom to d o so (intensity-preference) and their abi lity to continue an exercise bout with an imposed intensity (intensity-tolerance). Ekkekakis et al. (2005) developed the Preference for and Tolerance of the Intensity of Exercise Questionnaire ( PRETIE-Q) and pr ovided some s upport for the predictive validity of thi s ins trument. Although the research in this area is st ill in its infancy this provides a promising avenue to explain the large inter-individual differences in the sele ction and tolerance of exercise intensities ( pacing) by individuals.[24] A number of psychological constructs are likely to positively or negatively shape the way we pa ce our e xercise. Thi s include s leve ls of trait and s tate anxiety, self-confidence, self-efficacy believes, mood, motivational orientation of the in dividual, th e en vironment an d personality. All these psychological

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Limitations to Physical Performance

69

variables will to some ext ent influ ence how the indi vidual wi ll ap praise th e upcoming tr aining s ession or co mpetition and th e decision on th e amount of effort to be e xerted. The way the ex ercise or competition is progressing will also influence the individual’s appraisal of the situation and determine whether to continue, put in more or less effort, or terminate the activity altogether.

CONCLUSION •

•

•

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

•

•

•

•

While ther e m ay be no argument th at li mits ex ist to whi ch human s can physically perf orm t asks, the c auses of s uch l imitations r emain fer vently disputed. Peripheral fatigue has been defined a s the loss of fo rce ca used by processes occu rring at or di stal to th e neuromuscular junction. I t is generally considered as fatigue occurring within the muscle. Central f atigue is associated with instances where the c entral nervous system has a diminished neural (brain) drive to muscle. The traditional model used to explain the occurrence of exercise –induced fatigue ho lds that t he car diovascular system lim its performance via exercise induced de ficiencies to t he delivery of blood, nutr ients and oxygen to the working muscles, by l ocal muscle utilisation processes for the r e-generation of ATP ( energy curr ency), and by limit ations to (pulmonary) blood circulation with the lungs for gas exchange. A new the ory suggests that s keletal muscle a ctivation i s c ontinually managed by a subconscious/conscious regulator in the brain which acts to protect vital organs from injury or damage. This sy stem has been termed the central governor model of metabolic control. Psychological factors interact t o c ontribute to negative a fferent information received by the brain and thus limit performance. Overriding negative sensations is fundamental to extending exercise capabilities from a psychophysiological perspective. It is poss ible to explain b rain r egulation of exercise perfo rmance b y considering that the br ain remains in relative states of consciousness (e.g. aware a nd s ub a ware). In this new conscious awareness model of regulatory co ntrol, t here i s no requir ement for a n elusiv e and p erhaps implausible intelligent central regulator within the subconscious.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

70

Andrew Edwards and Remco Polman

REFERENCES [1] [2] [3] [4] [5] [6]

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[7] [8] [9] [10] [11] [12] [13] [14]

Bassett, D . and E. H owley, Limi ting fa ctors for ma ximum oxyge n uptake and determinants of endurance performance. Medicine & Science in Sports & Exercise, 2000. 32: p. 70-84. Noakes, T., Physiological models to understand exercise fatigue and the adaptations th at predict or enha nce a thletic per formance. Scandinavian Journal of Medicine & Science in Sports, 2000. 10: p. 123-145. Noakes, T. , Ti me to move beyond a br ainless e xercise phy siology: t he evidence for complex regulati on of human exercise p erformance. Applied Physiology, Nutrition and Metabolism, 2011. 36: p. 23-35. Gandevia, S., Spina l an d sup raspinal f actors in hum an muscle f atigue. Physiological Reviews, 2001. 81: p. 1725-1789. St Clair Gibson, A., et al., The conscious perception of the sensation of fatigue. Sports Medicine, 2003. 33: p. 167-176. Bruce, J., Travels to discover the source of the Nile, in the years 17681773. 1804: General Books Club (2010). St Clair Gibson, A., et al., The r ole of in formation proces sing between the brain and peripheral physiological systems in pacing and perception of effort. Sports Medicine, 2006. 36: p. 705-722. Abernethy, B., Attention, in Handbook of sport psychology H.A.H. R.N. Singer, & C.M. Janelle Editor. 2001, John Wiley: New York. Magill, R ., Mo tor learning an d control: co ncepts and applications. 9th ed. 2011, New York: McGraw Hill. Portas, C ., et a l., A sp ecific role for the thalamus in m ediating the interaction of at tention and arousal i n hu mans. The Journal of Neuroscience, 1998. 18: p. 8979-8989. Rolls, E. and A. Treves, Neural netwo rks a nd brain fun ction. 1998, Oxford: Oxford University Press. DeYoung, C., J. Peterson, and D. Higgins, Sources of openness/intellect: cognitive and neu ropsychological correlates of th e fifth factor of personality. Journal of Personality, 2005. 73: p. 825-858. Windhorst, U. an d G. Boorman, Over view: potential r ole of s egmental motor circuitry in muscle fatigue., in Fatigue, S. Gandevia, Editor. 1995, Plenum Press: New York. p. 241-258. Alexander, G. and M. Crutcher, Functional architecture of basal ganglia circuits: neural substrates of par allel pro cessing. Trends in Neurosciences, 1990. 13: p. 266-271.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

71

[15] Noakes, T., A . St Cl air Gi bson, and E. Lam bert, Fr om cata strophe to complexity: a novel model o f integrative cen tral neu ral r egulation o f effort and fatigue during exercise in humans: summary and conclusions. British Journal of Sports Medicine, 2005. 39: p. 120-124. [16] Taylor, J ., G. Todd, an d S. Gandev ia, ev idence f or a s upraspinal contribution to hu man muscle fatigue. Clinical and Experimental Pharmacology and Physiology, 2006. 33: p. 400-405. [17] Merton, P., Voluntary strength and fatigue. Journal of Physiology, 1954. 123: p. 553-564. [18] Fitts, R., Cellular mechanisms of muscle fatigue. Physiological Reviews, 1994. 74: p. 49-94. [19] Laurent, C . and J. Green, Mult iple models can con currently exp lain fatigue during hu man p erformance. International Journal of Exercise Science, 2009. 2: p. 280-293. [20] Herbert, R. and S. Gandevia, Muscle activation in unilateral and bilateral efforts ass essed by motor nerve an d cortical s timulation. Journal of Applied Physiology, 1996. 80: p. 1351-1356. [21] Bigland-Ritchie, B. an d J . Woods, Changes i n m uscle contractile properties an d neural co ntrol du ring human muscular fa tigue. Muscle and Nerve, 1984. 7: p. 691-699. [22] Bigland-Ritchie, B., et al., Changes in motorneurone firing rates during sustained maximal voluntary contractions. Journal of Physiology, 1983. 340: p. 335-346. [23] Kent-Braun, J., Central and peripheral contributions to muscle fatigue in humans d uring sustained maxim al eff ort. European Journal of Applied Physiology, 1999. 80: p. 57-63. [24] Lambert, E ., A. S t Clair Gibson, an d T. Noa kes, Complex systems model of fatigu e: integrative ho moeostatic control of p eripheral physiological sy stems d uring exercise in humans. British Journal of Sports Medicine, 2005. 39: p. 52-62. [25] St Clair Gibson, A., M. Lambert, and T. Noakes, Neural control of force output durin g m aximal an d submaximal exer cise. Sports Medicine, 2001. 31: p. 637-650. [26] Costill, D., H . Thom ason, a nd E. R oberts, Fr actional utilization of the aerobic capacity during distance running. Medicine & Science in Sports, 1973. 5: p. 248-252. [27] Bassett, D. and E. Howley, Ox ygen uptake: "cl assical" vs. "contemporary" vi ewpoints. Medicine & Science in Sports & Exercise, 1997. 29: p. 591-603.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

72

Andrew Edwards and Remco Polman

[28] Mier, M., et al., Cardiovascular adaptations to 10 days of cycle exercise. Journal of Applied Physiology, 1997. 83: p. 1900-1906. [29] Coyle, E., et al., Physiological and biomechanical factors associated with elite en durance cycling per formance. Medicine & Science in Sports & Exercise, 1991. 23: p. 93-107. [30] Coggan, A. and E. Coyle, Reversal of fatigue during prolonged exercise by ca rbohydrate infusion or i ngestion. Journal of Applied Physiology, 1987. 63: p. 2388-2395. [31] Coyle, E., et al., Muscle glycogen utilization during prolonged strenuous exercise wh en f ed carbohydrate. Journal of Applied Physiology, 19 86. 61: p. 165-172. [32] Hawley, J., E. Schabort, and T . Noakes, Carboh ydrate loading and exercise performance: An update. Sports Medicine, 1997. 24: p. 73-81. [33] Rauch, L., et al., Effects of carbohy drate lo ading o n muscle gly cogen content and cy cling p erformance. International Journal of Sport Nutrition, 1995. 5: p. 25-36. [34] Rauch, H. , A. S t C lair G ibson, an d E. Lam bert, A si gnalling role fo r muscle glycogen in the regulation of pace d uring prolon ged e xercise. British Journal of Sports Medicine, 2005. 39: p. 34-38. [35] Edwards, A. and T. Noakes, De hydration: cause o f fatigu e o r si gn o f pacing in elite soccer? Sports Medicine, 2009. 39: p. 1-13. [36] Hargreaves, M., Fatigue mechanisms determining exercise performance: integrative physiology i s sy stems bi ology. Journal of Applied Physiology, 2008. 104: p. 1541-1542. [37] Tucker, R . and T. N oakes, Th e ph ysiological regulation of pa cing strategy dur ing e xercise: a c ritical r eview. British Journal of Sports Medicine, 2009. 43: p. 1-9. [38] Tucker, R ., Th e anticipatory regulation o f performance: t he physiological b asis fo r pacing s trategies and the de velopment of a perception-based m odel for e xercise perfo rmance. British Journal of Sports Medicine, 2009. 43: p. 392-400. [39] Saunders, A., et al., The effects of different air velocities on heat storage and body te mperature in h umans cycling in a hot, h umid environment. Acta Physiologica Scandinavica, 2005. 183: p. 241-255. [40] Noakes, T., Lore of Running. 2002: Human Kinetics. [41] Noakes, T., Testin g for maximum oxygen consumption has produced a brainless model o f hu man exercise pe rformance. British Journal of Sports Medicine, 2008. 42: p. 551-555.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

73

[42] Hochachka, P., The lactate paradox: analysis of underlying mechanisms. Annals of Sports Medicine, 1988. 4: p. 184-188. [43] Ulmer, H., Concept of an extracellular regulation of muscular metabolic rate during heavy exercise in humans by psychophysiological feedback. Experimentia, 1996. 52: p. 416-420. [44] Noakes, T., The central governor model of exercise regulation applied to the marathon. Sports Medicine, 2007. 37: p. 374-377. [45] Tucker, R., et al., Non-random fluctuations in power output during selfpaced ex ercise. British Journal of Sports Medicine, 20 06. 40 : p. 912 917. [46] Lander, P ., R. Bu tterly, and A. Edwards, S elf-paced ex ercise is less physically challenging than enforced constant pace exercise of the same intensity: influence of co mplex central metab olic contro l. British Journal of Sports Medicine, 2009. 43: p. 789-795. [47] St Cl air Gibson, A . and T. N oakes, Evid ence for complex system integration and dynamic neural regulation of skeletal muscle recruitment during exercise in humans. British Journal of Sports Medicine, 2004. 38: p. 797-806. [48] Marcora, S., Do we reall y need a central governor to ex plain brain regulation of exercise performance? European Journal of Applied Physiology, 2008. 104: p. 929-931. [49] Impellizzeri, F., et a l., U se of RPE-based training load in so ccer. Medicine & Science in Sports & Exercise, 2004. 36: p. 1042-1047. [50] Whittow, G., S turkie's A vian Physiology. 5th Edition ed. 1999: Academic Press. [51] Edwards, A. , et al., I nfluence of moderate dehy dration on s occer performance: ph ysiological r esponses to 45 m in of outdoor match -play and the immediate subsequent performance of spor t-specific and mental concentration tests. British Journal of Sports Medicine, 2007. 41: p. 385391. [52] Masters, R ., R . Polma n, a nd H. Ha mmond, “Re investment”: A dimension of perso nality implicated i n s kill br eakdown under pressure. Personality and Individual Differences, 1993. 14: p. 655-666. [53] Mahoney, M., T. Gab riel, an d T. P erkins, Ps ychological s kills and exceptional ath letic per formance. The Sport Psychologist, 19 87. 1: p . 181-199. [54] Meyers, M. , A. L eUnes, an d A. B ourgeois, Psychological s kill assessments and at hletic pe rformance in collegiate rod eo athl etes. Journal of Sport Behaviour, 1996. 19: p. 132-146.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

74

Andrew Edwards and Remco Polman

[55] St Clair Gibson, A. and C. Foster, The role of self-talk in the awareness of physiological state and physical performance. Sports Medicine, 2007. 37: p. 1029-1044. [56] Krane, V. and J. Williams, Psychological c haracteristics of pea k performance, in Applied sport psychology: Personal growth to peak performance, J. Williams, Edi tor. 2010, McGraw Hill : New York. p. 169-188. [57] Eklund, R., A season l ong investigation of competitive cogn ition in collegiate wr estlers, Research Quarterly for Exercise and Sport, 199 4. 65: p. 169-183. [58] Nicholls, A., N . Holt, an d R. Polman, A ph enomenological ana lysis of coping effectiven ess in go lf. The Sport Psychologist, 2 005. 19: p. 111130. [59] Lazarus, R., Stress, appraisal and coping. 1984, New York: Springer. [60] Nicholls, A., et a l., Stressors, coping, and coping effectiveness: Gender, sport t ype, and abil ity differences. Journal of Sports Sciences, 20 07. 25(1521-1530). [61] Lazarus, R., Stress and em otion: A new synthesis. 1999, Springer: New York. [62] Polman, R., Elite athletes’ experiences of coping with stress, in Coping and emotio ns i n sport, M.J. J. That cher, & D. Lava llee Edito r. 201 1, Routledge. [63] Nicholls, A., et al., S tress appr aisals, coping, a nd c oping eff ectiveness among international c ross-country runners d uring training and competition. European Journal of Sports Science, 2009. 9: p. 285-293. [64] Nicholls, A., e t al. , An exploration of th e two-factor schematization of relation meaning and emotions among professional rugby union players. International Journal of Sport and Exercise Psychology, 2011. 9: p. 114. [65] Zakowski, S., et a l., A ppraisal control, coping, and stress in a community sample: A t est of the Go odness-of-Fit hypothesis. Annals of Behavioural Medicine, 2001. 23: p. 158-165. [66] Ekkekakis, P., E. Lind, and S. Vazou, Affective responses to in creasing levels of ex ercise intensity in no rmal-weight, over weight, and obese middle-aged women. Obesity, 2009. 18: p. 79-85. [67] Compass, B., Coping a nd stress d uring childhood a nd adolescence. Psychological Bulletin, 1987. 101: p. 393-403.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Limitations to Physical Performance

75

[68] Pollard, R. and G. Pollard, Long- term tr ends in home ad vantage in professional team sports in North Amer ica an d England. Journal of Sports Sciences, 2005. 23: p. 337-350. [69] Koller, M., M. Haider, and H. Recher, Metabolic stress during different work loads as personality-related risk factor. Activitas Nervosa Superior, 1984. 26: p. 134-137. [70] Costello, C. and H. Eysenck, Pers istence, personality , a nd motivation. Perceptual and Motor Skills, 1961. 12: p. 169-170. [71] Shiomi, K., Pe rformance diff erences between ex traverts and introverts on exercise using an ergometer. Perceptual and Motor Skills, 1980. 50: p. 356-358. [72] Courneya, K. and L. Hells ten, Personality cor relates of exercise behaviour, motives, barriers and preferences: An application of the five factor model. Personality and Individual Differences, 1998. 24: p. 625633. [73] Ekkekakis, P. , E. Ha ll, a nd S. Petruzzello, Som e like it v igorous: measuring individual differences in th e preference for a nd toler ance of exercise intensity. Journal of Sport & Exercise Psychology, 2005. 27: p. 350-374. [74] Noakes, T., How did A V Hill understand the V⋅ O2 max and the ‘‘plateau phenomenon’’? S till no clarity? British Journal of Sports Medicine, 2008. 42: p. 574-580.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved. Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Chapter 4

MONITORING AND SELF-REGULATING TRAINING

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

4.1. ABSTRACT The ai m o f this chapter is to examine the basis of generi c and selfregulatory sy stems for monitoring training and to i dentify ski lls wh ich may assist in optimising training outcomes. Numerous systems have been developed for monitoring training responses such as by heart rate or other metabolic variables. However, such systems are unlikely to be suitable to all exercise situations where physical con ditioning, type o f exercise, or the env ironment can ch ange from day to day. A ratin g of p erceived exertion system for monitoring training is discussed, as a re specific selfregulatory ski lls w hich may assist i n the d evelopment of a n opti mal training strategy.

4.2. INTRODUCTION The an cient Gr eek tetrad ( see chapter one) d emonstrated an early appreciation of the need to vary the intensity and focus of training from day to day t owards a specific goa l (e .g. th e Olympics) [ 1]. It seem s clear that thorough plan ning an d implementation of an appropriate tr aining programme are v ital considerations for pr eparing a thletes f or competition or f or individuals aim ing to a chieve a spe cific personal ta rget (e .g. wei ght lo ss or improved fitness). The content of a training programme is highly specific to the needs of the individual an d consequently task -specific c onsiderations fo r training in

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

78

Andrew Edwards and Remco Polman

different contexts are addressed in subsequent chapters of this book. However, the u sefulness o f a training prog ramme extends bey ond s imply performing physical t asks in th e anticipation t hat t hese wil l l ead to the a chievement of goals. A systematic method of tracking performance outcomes in response to the training stimulus (e.g. load) is vital [2, 3]. This is the means of identifying whether or n ot the stimulus is ap propriate f or the individual an d that key targets are r egularly att ained. I f the training st imulus is inadequate, physiological ad aptation will not be optimal while o ver zealous training c an lead to s ustained o verreaching a nd eventually to o vertraining [ 4]. It is therefore of c onsiderable impor tance th at tr aining is regularly checked vi a a systematic approach to monitoring both tangible outcomes (e.g. performance) and some form of feedback as to wh ether or not th e prescribed stimul us (training load) is appropriate for the individual [5, 6].

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

4.3. METHODS TO MONITOR TRAINING OUTCOMES Monitoring training requires the assembly of relevant, usable information. Gathering inf ormation for no sp ecific purpose is po intless and can lead to situations wh ere u nreliable, inc onsistent data are acted upo n si mply be cause these ha ve been collected. I t is th erefore i mportant to det ermine how the monitoring of t raining will be helpful, what information is useful, and how to best obtain reliable data. Modern t raining methods usuall y ad opt the p rinciples of either linear or non-linear p eriodization [7 ], t hereby focu sing on or em phasizing different qualities at various stages of the tr aining programme. Therefore, the obj ective indices used to monitor t raining may al so nee d to differ, de pending on t he activities un dertaken. This c an pr ove pr oblematic i f, f or e xample, a physiological var iable (e.g. he art r ate) is use d to gaug e th e tr aining response and that variable is not relevant or overtly stressed for all compo nents of th e programme (such as when resistance training) [5, 8, 9]. The s implest, most common an d pr obably effec tive too l of monitoring training outcomes is for an athlete to m aintain a tr aining log [10]. Although obvious, a training lo g co ntaining p erformance o utcomes an d det ails of t he training load is not always maintained. This log is a personal monitoring tool for an individual and should represen t a record of session-to-session performance outcomes and thoughts or feelings about the session. The training log often can also reflect factors peripheral to training such as s leep, diet, and other stressors which may all indirectly impact on training and performance. In

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Monitoring and Self-Regulating Training

79

addition to the individual’s log, the t rainer/coach s hould als o maintain a training log of outcomes for each athlete in their squad as this can be useful to identifying areas o f concern or explanatory observations f or go od or poor performance. It can also act as a d ata source f or f uture d evelopment of performance targets and improved session design. Perhaps most importantly, it can b e us ed to su mmarise planned vs. actual w ork co mpleted, co mpare the perceived r ating of the athlete in response to the intended intensity o f the work, and contain the detailed description of performance outcomes. Monitoring training should address the issue of session-to-session exercise intensity for ind ividuals [2, 3]. This ha s acute i mplication to w hether or no t each s ession is of a meaningful i ntensity for different athletes. For exampl e, two athletes mi ght complete t he same tr aining session, ac hieve the s ame training performance, an d y et experience dif ferent ad aptive responses [11]. This is most often due to differences in their maximal performance capabilities whereby a more a dvanced performer may a chieve the sa me r esult as their training p artner bu t w ith a lower e ffort a nd reduced physiological s train [ 5]. This wou ld clearly represent a lo wer relative training load fo r the more advanced ath lete and ther efore pr esent a r educed stimulus for po tential adaptation which might impede further progress [12]. Therefore, performance should b e monitored n ot j ust s imply in ter ms of performance ou tcome ( e.g. performance tim e) bu t als o in terms of physiological and psy chological responses to t he impos ed training stimulus [3]. This will enable th e co ach t o determine whether or not the stimulus from an individual session or even the overall programme is appropriate. Such a systematic approach also minimizes the p otential for issu es o f o verreaching and ov ertraining which may occur if the stimulus is too severe or is generalized to a group. Numerous systems have been proposed for monitoring training responses (e.g. [3, 13]) using a var iety of metabolic and performance variables. Several of the most common systems are discussed in the following chapter.

4.3.1. Metabolic and Performance Outcome Variables The measurement of heart rate during a training session is commonly used as a bio feedback marker to estimate physiological response, or to d irectly set the i ntensity of e xercise ( i.e. r unning a t a l evel of effort to produce a target heart rate) [13]. Increases to heart rate during aerobic exercise are well known to be directly related to the intensity of work performed and, as a consequence,

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

80

Andrew Edwards and Remco Polman

this me asurement may provide us eful explanatory info rmation to supplement performance outcomes. Cardiac ou tput (C O) i s w ell k nown to increase to match t he de mand of exercise [14] and this is accomplished by increases to both stroke volume (SV) and heart rate (HR) (CO = SV x HR). Stroke volume may increase from ~100 to 160 mL (approx 50% increase) during exercise but not in d irect relation to exercise intensity; h owever, heart r ate increases gr adually in r esponse t o exercise, f rom ~ 6 0 b/min a t rest to maximal levels ~ 185 b /min d uring strenuous e xercise ( approx 200% increase). Therefore, incr eases to heart r ate accounts for a larger proportion of the increase in cardiac output [15] and, as such, this easily m easured vari able has gain ed co nsiderable po pularity as a means of quantifying physiological stress in response to exercise. Heart rate s can provide useful feed back of prog ressive cardiovascular changes to standardised exercise sessions. Also, numerous studies have shown that aerobic capabilities improve if the sustained exercise intensity is broadly maintained within a heart rate zon e o f 55-70% of max imum age p redicted heart rate ( e.g. 220 – age) [ 14]. This kn owledge c an provide r eassurance to novice athletes that the tr aining s ession has pr ovoked an ap propriate physiologic response, or t hey can alternatively directly pace an exercise bout to achieve a target heart rate in the required target zone. Monitoring, or pr e-setting, training intensity via heart rate methods can yield usef ul biofeedback in formation for a thletes and their co aches, but it i s difficult to use these data bey ond simple identification of the required training zone fo r a s ingle s ession. To ex trapolate this information for the pu rpose of monitoring training outcomes, a system called the TRaining IMPulse (TRIMP) was developed [13]. The T RIMP is a practical tech nique fo r monitoring the intensity of prescribed physical work acr oss sessions and estimates a tr aining impulse based on session duration and the average heart rate in response to it: Heart R ate T RIMP = tr aining se ssion duration x av erage s ession heart rate. The TRIMP therefore, represents a basic dose of aerobic training such that a 30 min exercise session completed with an a verage heart rate of 160 b/min results in a TRIMP of 4800 ( 30 min x 160 b /min = 4800). A longer training session (e.g. 40 m in) completed at the same heart rate (intensity) (160 b/min) represent a greater sust ained met abolic chal lenge and so der ives a hig her TRIMP. Tabl e 4.1 d emonstrates a comp arison o f TR IMP outcomes for th ree different trai ning sess ions. The accumulation of sess ion to session TRIMP

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Monitoring and Self-Regulating Training

81

scores w ithin a cycle of tr aining ( e.g. microcycle) c an therefore be used to quantify a basic training load. Table 4.1. A comparison of heart rate TRIMP outcomes for three training sessions and their accumulated score as an indicator of cyclic training load Session

Time (min)

Average Heart rate (b/min)

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

High intensity 25 192 continuous run Continuous steady run 30 160 Continuous steady run 40 160 Aerobic circuit training 60 150 Total TRIMP load (accumulation of selected scores)

TRIMP (duration x HR) 4800 4800 6400 9000 25000

The TRIMP me thod e nables coaches and a thletes t o plan and monitor a range o f aerobic activities usin g bo th expected heart r ates (applying th e TRIMP to plan sessions if usi ng a t arget hear t r ate) and s ubsequently the actual h eart rate r esponses ach ieved (applying TRIMP to monitor se ssion responses). At a basic le vel, it fac ilitates prac tical orga nisation of aerobic training and b roadly e nsures wee k-to-week (or cycle-to-cycle) ba lance of training load can be planned and achieved. Although this system is intuitively a ttractive an d simple to implement, a significant f law is th at i t d oes not accurately dist inguish be tween different levels of activity. As identified, the ex ample of a 30 min e xercise bo ut a t an average heart rate of 160 b/ min pr ovides a TRIMP of 48 00 (Table 4.1). However, it is also evident that 25 minutes of exercise at an average heart rate of 192 b/min also results in a TRIMP of 4800. These two sessions are likely to produce qu ite differen t metabolic outco mes, u tilise d ifferent energy systems and require differential recovery periods despite being TRIMP being matched. Quite obviou sly, twenty five m inutes of ex ercise at an average hea rt rate of 192 b/min is a much harder training session than 30 min at 160 b/min. To overcome this limitation, the basic TRIMP concept was modified (e.g. Foster et al. 200 1) to i ncorporate weighting for i ntensity of exe rcise in the calculation. I n this r evision, a h eart rate zone n umber ( 1-5) replaces t he average heart r ate f rom the or iginal TR IMP cal culation to qua ntify tr aining intensity (Table 4.2).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

82

Andrew Edwards and Remco Polman

The revised heart rate zone TRIMP is therefore calculated as the total time spent in each zone. For example, 30 min of aerobic exercise completed at an average heart rate of 160 b/min by an athlete wi th a m aximum h eart r ate of 200 b/min (80% of max heart rate) would place that individual in zone 4. The calculation of duration (30 min) x hear t rate zone (4) p roduces a revised TRIMP of 120. Using our prev ious comparison with a har der session, 25 min at an average heart rate of 192 b/min by the same athlete places the session in zone 5 (96 % o f max imum) and multiplied by exercise d uration (2 5 min) produces a T RIMP of 1 25. This method now distinguishes b etween the two sessions where the intensity of sustained physical effort is different. It is only a subtle difference but potentially meaningful.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Table 4.2. Heart rate zone TRIMP [3]. This system allocates average heart rates into zones for subsequence TRIMP calculation (duration x zone) Heart Rate Zone 1 50-59 2 60-69 3 70-79 4 80-89 5 90-100

% of maximum heart rate

There ar e, o f co urse, limit ations to usi ng any s ingle physiologic var iable (e.g. heart r ate, or blo od lactate concentrations) for th e pur pose of planning and/or monitoring training. The par ticular limitation of both the TRIMP heart rate methods is that they are only suited to endurance-based exercise. Strength, speed, anaerobic and technical sessions, which do not evoke high heart rates or where heart rate does not accurately reflect overall effort, cannot be calculated accurately by these means. A furth er l imitation to the use of heart rate methods i s the i mpact of environmental conditions on the cardiovascular system. For example, it is well known that th e heart mus t be at faster than nor mal to mai ntain the r equired cardiac output in hot conditions due to peripheral redistribution of blood to the skin [16]. Consequently, in hot conditions, power output is lower than for the same heart rate as in cool conditions [8]. This has implications for assigning or evaluating tr aining sessions to h eart rate z ones wh en the en vironmental conditions differ between sessions. As indicated earlier in this section, heart rate is a metabolic response to the exercise performed and as such i t also t akes time t o r eflect t he w ork already

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Monitoring and Self-Regulating Training

83

being performed. F or e xample, at the start of a r unning in terval, heart r ate takes se conds, or e ven minutes i n some cases t o a ccurately reflect th e t ask [17]. During a short sprint he art r ate inc reases, ye t simply re flects a cardiodynamic, general increase in frequency which does not accurately reflect the task requirem ents an d thu s c annot give a n accu rate m easurement of the applied effort in that context. Although heart rate methods are generally well suited to endurance events, these may also not be r eliable f or ultra-endurance a ctivities such as Ironman triathlon events [18]. During these events, most competitors are able to sustain a constant heart r ate, bu t due to p hysiological c hanges s uch as dehydration (inducing cha nges to blood visc osity), car diovascular dr ift occurs. The t erm cardiovascular dr ift des cribes th e gradual time-dependent ‘ drift’ in fa ctors such as stroke volume (which declines as blood viscosity increases) [19]. This means that heart rate must increase during such prolonged exercise to sustain a constant car diac outp ut and co nsequently the ef fort required to sustain a constant target heart rate increases over the course of th e event. Therefore, it can be misleading to use this as an external indicator of exercise intensity for the purpose of pacing. The relat ively recent development of reliable telemetry s ystems (s uch as power meters and G lobal P ositioning Sy stems: GP S) for the measurement of power ou tput and distances co vered can b e us eful for spor ts su ch as cy cling, rowing and team sports [2]. These can provide useful feedback for estimations of a ccumulative wor k achi eved in a se ssion, movement p atterns and other outcome driv en data. Ho wever, d ay t o day fluct uations of health/wellbeing /soreness and so on als o affect the ab ility to attain a given power ou tput, as does t he environmental con ditions, sur face c onditions and t errain. Examination of power output or GP S data does not provide any physiological explanation for chang es to per formance, bu t if co upled w ith perceptu al feedback ( i.e. RP E e valuations) t his could b e a useful means of qu antifying training. For example, the pow er output at tained at ke y stages of an exercise bout can be coupled with o ther sensory information to determine regulatory check points of physical and mental wellbeing in comparison to previous bouts of exe rcise ove r the sa me course or in re sponse to the same ta sk. If, for example, a cy clist cli mbed to t he top of a steep hill it wou ld r epresent considerable physical work. The work required to r each to the top of that hill will be the same regardless of how fast or slow it was climbed; however, if the climb w as twice as f ast as the ti me before, the cyclist would have exerted twice t he a mount of a verage power , uti lized different energy sy stems and worked at quite a different intensity. Therefore, this information is useful, but

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

84

Andrew Edwards and Remco Polman

should be coupled with additional sensory data to properly assess the extent of physical challenge.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

4.3.2. Self-Regulated Management of Training The prin ciples o f sel f-regulation suggest t hat suitably c onstructed RP E methods o f monito ring training are likely to be eff ective across all types of exercise. The American Coll ege o f S ports Me dicine position st atement r ecognizes RPE as a v alid and reliable indicator o f l evel of phys ical exertion du ring endurance exercise [2 0]. Thi s psy chophysiological approach to monitoring training requires athletes to rate on a numerical scale their perceived feelings relative to an exert ion level [ 21]. RPE r epresents a cons cious per ception of effort experienced during exercise and consequently has considerable practical value to the athlete. I n ad dition, exer cise corresponding to h igher leve ls of energy ex penditure and p hysiologic str ain cons istently produce hig her RPE ratings [ 22] and i ndividuals appear to l earn quite quickly to exer cise at a specific RPE [17]. Exercise paced at an RPE of 13-14 (somewhat hard; 6-20 RPE sc ale) c onsistently coincides wit h approx 70% HR max dur ing cy cle ergometer and tr eadmill e xercise, whil e other research h as shown RPE t o be related to the percentage of heart rate during running and to the time spent at different intensities corresponding to heart rate at l actate thresholds [ 22]. Consequently, exer cising a ccording to RP E pr ovides an ef fective way to prescribe exercise b ased on individual’s per ception of effort tha t c oincides with individualised metabolic strain (e.g. %HR max, % V⋅ O2 max, blood lactate concentration). The practical usefulness of RPE has also been suggested to extend beyond simply self- regulating or monitoring the i ntensity of trai ning, to actually replacing heart rate in the calculation of TRIMP for the assessment of training load. As RPE r elates to all ty pes of exer cise and not merely aerobic sessions [3, 5 ] i t means the same monitoring sy stem can be applied to all ty pes o f sessions and is thus hi ghly attractive to co aches s eeking to qui ckly a nd effectively monitor all training sessions. The session rating of perceived exertion (RPE) TRIMP model is a simple system for co aches to monitor t he load of ALL diff erent train ing modalities (technical, t actical, endurance, sp eed an d strength). W ith this sy stem, individuals are required to provide an RPE based on the 10-point (CR10) scale [21] (F igure 4.1) for each exercise session which is then multiplied by the

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Monitoring and Self-Regulating Training

85

training s ession duration (min) to det ermine training load. Week ly o r otherwise periodically summed training load (i.e. microcycle) can then offer a tangible r epresentation of t he training experience a nd offer a r apid, effective and m eaningful meth od for monit oring the training ex periences acr oss m ost sport and exercise contexts. This makes it a very powerful monitoring tool for many different types of training sessions and/or sports. Rating 0 Rest 1 2E 3 Mo 4 Som 5H 6– 7 Very 8– 9– 10 Maxi

Descriptor Very, very easy asy derate ewhat hard ard hard mal

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 4.1. the CR10 Borg Rating of Perceived Exertion scale [21].

To cal culate t he RPE TRIMP, the sess ion dur ation is m ultiplied b y the RPE eval uation. F or example , for 60 minutes of training, rated as very ha rd (RPE = 7), TRIMP = 60 x 7 = 420. Using the RPE TRIMP system, the individual provides a ‘global’ rating of the s ession a nd s o enables co mparisons be tween different ty pes of tr aining (Figure 4 .2). Th is sy stem has also b een shown to be useful for re sistance training, further demonstrating considerable di versity of its appl ication [5]. It is also potentially useful for athletes in sports that involve a variety of training modes, especially anaerobic and technical training, e.g. team games and power sports. Athletes in these sports may train for long periods of time, while their average heart r ate f or th e session may be l ow. Us ing h eart r ate TRI MP methods, the overall training l oad may a ppear of low er str ess t han actually experienced by factors such as lo cal musc le soreness, men tal fatigue a nd dehydration. RPE eval uations cap ture th e afferent sensations r eceived by th e brain and can thus represent a holistic view of metabolic challenge across all physiologic systems when either dev ising a t raining load , o r e xamining its impact on the individual.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

86

Andrew Edwards and Remco Polman

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 4.2. An RPE-based system for monitoring responses and performance outcomes from a training programme. As the brain regulates all physiologic systems and perceived sensations, it is possible for this system to provide a quick and effective means of determining training load and response across all exercise types.

In su mmary, there are n umerous methods f or obj ectively ev aluating th e intensity and lo ad o f trai ning. The b asic heart rat e T RIMP method may be suited in s ome cases to those training for general h ealth benefits; however, it contains s everal inac curacies which are to some extent address ed by th e TRIMP heart rate zone method. This is a simple modification for monitoring all aerobic tr aining and is generally well sui ted for end urance a thletes. Ther e are several confoundin g var iables relating to differences i n environmental conditions, d ehydration and train ing where sustai ned high hear t r ates do not properly r eflect the demands of the task. The use of v ariables su ch a s blood lactate concentrations as a gauge of training intensity or training adaptation are largely impractical, except t o t hose wi th access to port able blood testing equipment. It co uld not be used pract ically to quantify responses t o t raining. Monitoring power output or p erformance da ta pr ovides a us eful index of objective outcomes fr om trainin g, but this would best be cou pled with a system of biofeedback ( such as RPE) to properly exp lain the bas is be hind performance. Th e fin al method, sess ion RPE, is the most ver satile and practical si nce i t ca n be us ed t o ex post facto rate th e load of any kind of training and al so ca n be u sed ante eventum to pre s et a l evel of effort to perform exer cise i.e. per form t he se ssion at a pr escribed RPE. Coupled with performance outcome data, session RPE provides a powerful and practical tool for both setting the exercise intensity and also for monitoring training via selfregulation (Figure 4.2). However, the ability to use a self-regulatory system in sport and exercise may take some training and skill [23].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Monitoring and Self-Regulating Training

87

4.4. SELF-REGULATORY TRAINING SKILLS

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

‘Good judgment is the result of experience. Experience is the result of bad judgment.’ Mark Twain

Inexperienced athletes are unable to pace themselves effectively compared to exp erienced athletes [24]. This is lar gely due to th e in tricacies of performing such a compl ex s kill [ 25] an d specific self-regulatory training is likely to assist i n the capacity to improve t he execution of a pacing strategy. This is a con cept implicitly based on the in tegration of mind and bo dy in regulating performance [26]. As ac tive muscl es a nd th e cardiovascular sy stem ap proach the ir li mits during su stained e xercise, th e br ain has to overcome incr easingly ne gative stimuli sugg esting it might b e a good id ea to reduce motor d rive an d slow down. This is not usually desirable in a competitive situation and so the brain must resist increasingly potent n egative stimuli in th e effo rt to sus tain the required pa ce. Th is ine vitably d rives the p erception of e ffort e ver up wards until such time as negative (afferent) sensations can no longer be tolerated and the athlete feels compelled to either slow down, stop, or, if well-judged, cross a f inish line in a physical stat e co nsidered to b e of maximal manageable discomfort [2 7]. As di scussed prev iously t hough, this d oes not rep resent a state of cat astrophic exh austion at which ti me a p hysiological sy stem has failed [ 28]. It is a phy sical s tate determined by th e i ndividual’s a ppraisal, based on the phy sical limits of to lerability the individual is ab le to endure in response to t hat activity. It is a matter of pain/d iscomfort management and once accepted that this is THE limit ation to exercise p erformance, i t is trainable. In 2 007, ‘ Brain Training for Ru nners’, Matt F itzgerald [23] presen ted a practical inter pretation of how to integrate mind-body for the purpose of optimising tr aining by f eel r ather than external i nstruction. The concept of training the b rain may see m u nusual to many coa ches an d ath letes, but th e concept st rongly relates t o overriding c entral regulatory (brain) c ontrol o f performance. If th e brain lim its our physical efforts, per haps with s ystematic and dedicated training we can get closer to our true physical limits. Of course this do es not me an ig nore al l phy sical training and merely con centrate on training the mind; the brain is the limitation to physical effort and so rel easing some of ou r n atural inhibition may facilitate gr eater physical training and performance outcomes. Th erefore, physical training r emains v ital t o a thletic

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

88

Andrew Edwards and Remco Polman

success, but specific (brain) self-regulatory training skills may be useful to aid this process. ‘The body does not want you to do this. A s you r un, it t ells y ou t o stop but the mind must be strong. You always go too far for your body. You must handle the pain with strategy…It is not age; it is not diet. It is the will to succeed.’ Jacqueline Gareau (Boston Marathon winner, 1980)

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

4.4.1. Coping Strategies Participation in sport an d e xercise is a lmost inevitably associated wit h encountering str essors an d th ese c an i nclude ma king technical or tactical mistakes, of ficials ma king wr ong de cisions and bodily feedback associated with the physical work performed (e.g., pain or fatigue). The dev elopment of appropriate coping s trategies may help ath letes to perceive stres sful events positively as challenges rather than negatively as threats. Athletes can b e taught c oping strategies. Prior to implementing a c oping intervention it is useful to first assess the stressors athletes regularly encounter in their trai ning and co mpetition as wel l as the copin g strategies they use to deal with these situations and their perceived effectiveness. Hence, athletes are frequently not aware of which situations cause stress to them and often do not invoke ad equate coping str ategies wh en experiencing a s tressful event [29 ]. Not coping with a stressful event is related to frustration [30] and performance decrements [31]. Evidence app ears to sug gest that at hletes improve pe rformance by developing co ping st rategies to make the ex ercise situation b etter. Fo r example, one study of competitive rowers induced pain by occluding specific limbs during tr aining and obser ved t hat t he r owers showed b oth gr eater tolerance to pain and also reported using a range of their own coping strategies to manage the pain. Th ese coping s trategies wer e reported to be th e same as used i n competition thus s uggesting t heir spor ting ex perience had pr epared them to tolerate considerable pain and also to develop their own methods for dealing with it; certainly more so than untrained subjects [32].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Monitoring and Self-Regulating Training

89

4.4.2. Mental Toughness

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

‘Sport is not about being wrapped up in cotton wool. Sport is about adapting to th e un expected and being ab le t o modify plans at th e last minute. Sport, like all life, is about taking risks.’ Sir Roger Bannister

Clough, Earle and Sewell [33] suggest that mental toughness consists of 4 inter-related but i ndependent factors: (1) Co mmitment ( stickability, abili ty to execute t asks succ essfully des pite any pr oblems or o bstacles that arise); ( 2) Challenge (regard challenges as opport unities f or self dev elopment); ( 3) Control ( in co ntrol of environment, emo tions and li fe); and (4) Confiden ce (self-belief to s uccessfully c omplete tasks). Although ope rationalised as a personality construct these four factors which make-up mental toughness each relate to poten tially trainable characteristics. Mental toughness training would therefore be a gateway to influence exercise behaviour in athletes and help the athlete to buffer against stress [29]. The way an ath lete a ppraises a s tressful encounter has cons equences f or the am ount of stre ss expe rienced a nd the selection of coping strategies. F or example, if significant stress is experienced it will be difficult for the athlete to make r ational and accurate j udgements. I n such a situation i t wou ld be advisable f or the athlete to fir st down-regulate t heir e motional s tate be fore trying to sol ve th e pr oblem. Athle tes w ith more mental to ughness h ave been shown to appraise str essful events as les s stressful, mor e controllable [34], view the stressor as a challenge rather than threat [35], tolerate pain better, and have lo wer lev els of p erceived exertion. Additionally, m ental to ughness h as been f ound to be r elated t o the us e of more ad aptive copi ng s trategies and greater use o f some performance strategies in competition, namely activation, relaxation, self-talk, emotional control, and goal setting [36]. Tak en together, these fi ndings might explain why bein g mentally tough i s often associated with success in sport. Increasing an athlete’s mental t oughness could b e accomplished by teaching athletes psychological skills which are akin to stress management and include thinking optimistically ( see the ch allenge r ather tha n t he thr eat), development of structured approaches to comp etition and tr aining ( e.g. pr eperformance r outines), l earning to deal wi th ner vousness (e.g. pr ogressive muscular relaxation, breathing), le arning n ot to worry ab out w hat can’t be controlled, learning from failure or mistakes, use of positive self-talk, keeping perspective and not dwelling on mistakes.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

90

Andrew Edwards and Remco Polman

Baron and co-workers [37] recently suggested that athletes select optimal pacing strategies by associating a level of emotion with the ability to maintain a particular pace. At the high end of exercise intensities, this is likely to be a negative emo tion driven by unwillingness to in cur sign ificant physical discomfort unless it is absolutely necess ary. To r esist t he urge to s low d own requires considerable men tal toughness a nd, intuitiv ely, most athlete s will know that fighting the temptation to ease off in training is a significant battle. This is a batt le th at can be eas ily l ost by inter mittently at tending t raining sessions and/or simply completing work directed by a coach with no reg ard to personal investment of significant effort. There are many occasions in training where other commitments mean it is diff icult to attend sessions, when it is too cold or too hot to apply the necessary effort dur ing tr aining, wh en exter nal factors h ave meant a thletes we re mentally f atigued prio r t o tra ining a nd so were u nable to f ully co mmit, or si mply when the athlete did n ot apply themselves each day with the same dedication. Training is a constant battle for most i ndividuals a nd m ental to ughness is required to b oth to lerate the discomfort of training and t o withstand t he des ire to simply p ut it off to another day. As Sir Rog er Ban nister i dentifies: ‘Sport is n ot abo ut being wrapped in cotton wool.’ It takes dedication, commitment and the confidence to succeed. Such ch aracteristics of men tal t oughness ap ply to all p hysical activity situations. We are not all likely to wi n an Olympic medal or even win a race, but we do need mental toughness to stick to a task and achieve our aims.

4.4.3. Improvisational Training This form of training does not mean an athlete should simply turn up to an athletics tr ack a nd co mmence ex ercise w ithout con sciously considering, or adhering to, a training plan. What it means is that the athlete should consider, be given, and explore new innovative options in training. Options when placed in the han ds of ine xperienced athletes ca n lead t o poor choic es, bu t selfregulatory exercise is simply a process of listening to the body and should not be confused as a process of ignorin g the ad vice of experienced coaches. Devising a training s chedule means wo rking to an ove rall plan , while also facilitating flexibility. The ancient Greek tetrad was criticised by many at that time for bein g inflexible to individual differences and i t is i mportant we recognise the need to amend training according where r equired. A m ethod to develop flexibility in resp onse to training is simply to have options and to use

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Monitoring and Self-Regulating Training

91

them. F or more expe rienced athle tes with greater understanding of thei r limitations, this may in volve great er autonomy an d mo re choice . For l ess experienced a thletes o r general exer cise en thusiasts, t he opti ons w ould therefore be more li mited. F or exa mple a coac h may deter mine a pa rticular style o f s ession which on a given day f its w ithin the ov erall p lan. T here is nothing wrong with this an d t hat sty le of sess ion coul d st ill i nclude v ariety encompassing choices of low, m edium and high intensity variations. To make a properly informed choice, the athlete needs to consider their feelings on th e day in relation to the session requirement, its place in the week’s schedule and other factors such as suitability of the session to the environmental conditions. The coach can certainly guide the athlete to ensure the required training load remains on track, but flexibility and inclusion in the decision-making process will l ead to po sitive psychological associations, g reater engage ment, enjoyment and hopefully improved performance [17]. A further example of improvisational training is to perform some exercise sessions by tempo. Compl eting sustained periods of t raining at competitive pace enables the athlete to improve task familiarity and respond to the exercise challenge confidently when required to do so in a race. However, exercise in accordance wi th te mpo re fers t o the sk ill of li stening t o the bod y’s op timal rhythm and deter mining a self-selecte d preference f or wor k int ensity. This does no t necessarily mean choosing a l ow in tensity of ef fort b ecause i t feels easy, it is t he voluntary desire to ex plore different te mpos (e.g. oc casionally over te mpo) of pe rformance and e xperience dif ferent ( e.g. heightened) physical sensations in largely familiar/routine training circumstances. In competition, the rhythm of performance and level of tolerable physical discomfort are invariably increased and th is makes tempo work an important feature of training. For example, what may seem over-tempo in training may coincide wi th r ace p ace in compe tition. To simply w ork a t a ‘ race pa ce’ in training based on prior race per formance times ca n lead to disappointment, anxiety and an inability to sustain the required level of work. Augmented raceday m otivation often l eads to min or increases in pace for the same level of perceived effort, but en abling the athlete to work at their naturally perceived race (high) tempo pace rather than externally forcing a pace upon them is more consistent with sel f-regulatory p rocesses. A re cent stu dy [ 38] f or e xample clearly demonstrated that when athletes are forced to adopt an externally paced intensity it is more physically demanding and leads to premature fatigue more than self-pacing a bout, even though th e power o utput is exactly the s ame. Therefore, va rying the t empo w ork ac cording to the a thlete’s p erception of their own relative intensities is the best mix.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

92

Andrew Edwards and Remco Polman

Central regulation infers t hat the br ain c ontrols performance an d, a s mentioned previously, part of that process is to pace a session (or bout) based on prior experience and o ther avail able knowledge of the task demands (e.g. distance or ti me) [39, 40]. Occas ionally sur prising an athlete with an unexpected ch ange in the s timulus such as by extending the distance or time can lead to an augmented exercise challenge if the aim of that session (e.g. a preconceived high intensity workout) is to ove rride central regulatory control [41]. If th e athlete has p aced the bout or sessi on to finis h in a particular physical co ndition, an acute (late in th e sess ion) change to the stimulus can increase the level of physical discomfort beyond that anticipated by the athlete. Of cours e, if this ty pe of s urprise i s over-used, it c an mean anticipation of surprise will be factored into the pacing plan by the athlete which will leads to more conservative, slower performances in training.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

4.4.4. Self-Confidence Being confident i n on eself and o ne’s ability are cr ucial to s uccess. Commitment to training requires dedication, to lerance to significant physical discomfort, and substantial self-sacrifice. Each of these attributes can, and are, displayed to a gr eater or lesser exten t by all in dividuals; but wit hout h igh levels of se lf-efficacy beli efs and self-confidence non e are likely to b e meaningful. If a n individual is not confiden t in his ability t o succ eed in the task (low se lf-efficacy beli ef), compromise i s i nevitable and most li kely wil l be evident by poor effort and adherence to exercise. Compromise is also likely for bo th (dim inished) to lerable level of physical discom fort the athlete is prepared to endure, and the sacrifices he is prepared to make. Confidence und erpins al l training and t his is where a co ach can be invaluable. The coach must not only tell the athlete he believes in him, he must actually believe in him a nd en courage th e athlete to believe in hims elf. Although ne arly all at hletes a nd coaches mus t wor k with a sens e of perspective and, to s ome ex tent dis appointment, th at can be managed w ith realistic expectations and goal setting. Young athletes experiencing rapid improvements tend to believe they will one d ay represent thei r c ountry, ap pear at th e O lympics, s core the winning goal in a W orld Cup match or break a world record. Th e coach’s role in confidence building and goal setting doesn’t mean the s hattering of childhood dreams, but it should be a matter of setting short and long term targets that can be attained, are appropriate to the athlete and can be obj ectively assessed and

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Monitoring and Self-Regulating Training

93

measured. Ap propriate go al setti ng is the cornerstone of c onfidence build ing and it is important th e co ach provides at hletes or exerciser with suc cessful experiences. This can b e done by setting short-term challenging, but realistic, goals w hich when achieved wi ll increase p erceptions of competence. Similarly, providin g athlete s or e xercisers wit h vicarious expe riences o r helpful verbal encouragements will enhance self-efficacy beliefs which in turn will result in enhanced athletic performance. It is important that individuals have the confidence to manage an exercise session, gai ned fr om prior ex perience in similar c ircumstances. Th is could include th e knowledge of s afe practice of liftin g w eights o r executing a complex fi ne mot or skill. Alternatively it cou ld be man aging eff ort a cross a series o f r epetition runs s o that t he en tire series i s co mpleted or having t he confidence to set off at a goo d p ace and self-regulate a ti me-trial, finishing with enough, but not too much energy intact. Knowing the task, the demands of it, whether and how it ca n be op timally completed are consequent to experience. Finally, a more recen t development in in fluencing particular ex ercise behaviour is to tap into unconscious processes. There is now some agreement that m any behaviours can be g uided by bo th explicit ( conscious, a ware) or implicit (conscious, s ub awa re) processes. In par ticular, through implicit priming t asks it is possible to manipulate and activate an individual’s motivation. This has resulted in exercisers improving the effort and duration of the e xercise bout as we ll as f uture e xercise f requency. In addit ion, the behavioural differences were accompanied by higher ratings in enjoyment and lower r atings of p erceived exertion [ 42]. The under lying mechanisms w hich accompany implicit or unconscious priming of exercise behaviour are unclear; however, such m echanisms c ould hav e a significant in fluence on paci ng strategies used by athletes and exercisers. In summary, the skills identified in this section are not exhaustive, but do identify a n umber o f factors w hich a ffect t raining behaviour (T able 4.3). Although t here is more e mpirical e vidence for t he ef ficacy of th ese psychological factors in r elation to athletic performance it is easy to see that these are also of benefit to the regular exerciser. It is an impor tant aspect that all thes e psy chological factors are tr ainable and wo uld help the athlete or exerciser to better self-regulate their behaviour. As with physical skills, mental or psychological skills need to be trained in a systematic way to be effective. To this end it is important that i ndividuals l earn a var iety of psy chological skills. Thi s will al low them to cope more effectiv ely wi th s tressors they encounter to circumvent the negative effects on performance and satisfaction.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

94

Andrew Edwards and Remco Polman

Table 4.3. Summary of selected self-regulatory training skills. Many of these skills inter-relate. Gains in mental toughness, improvisation, selfconfidence and self-efficacy could each be considered a strategy with which to self manage exercise. These strategies should be considered additions to existing training practices and not replacements

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Coping strategies

Description Practiced mechanisms to deal with stressful situations. Often classified as problem-focused, emotion-focused or avoidance coping strategies.

Mental toughness

Personality trait which helps to deal with negative sensations during exercise and helps to cope more effectively

Improvisation

Poor performance is associated with unfamiliar situations. Improvisation of training intentionally places the individual in different and unfamiliar situations.

Selfconfidence

Believe that you can perform a desired behaviour (e.g. to execute physical, perceptual, or psychological skill) Perception that you can perform a specific task successfully (situation specific self-confidence)

Self-efficacy

Example Problem-focused: Planning, goal-setting, increasing effort or concentration. Emotion-focussed: Breathing, imagery, self-talk. Avoidance: Block or stop thinking about stressful event. Training to sustain effort in the presence of considerable negative sensations. Interpreting stressful stimuli as a challenge rather than a threat. Occasionally varying pace during an exercise bout to adopt different tempos of performance. This may assist coping with the unpredictable demands of racing and competition. Confidence comes from practice, familiarity, experience and appropriate goal setting. Have successful performance accomplishments; see others completing the task successfully; receiving verbal acknowledgement that you are capable of executing the task.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Monitoring and Self-Regulating Training

95

CONCLUSION •

•

•

•

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

•

•

Monitoring training requires the assembly of relevant, usable information. Gathering information for no specific purpose can lead to situations where unreliable, inco nsistent d ata ar e acted u pon s imply bec ause these have been collected. The simplest, mo st co mmon and effective tool of mon itoring training outcomes is for an athlete to maintain a training log. The training log often can also reflect factors peripheral to training such as sleep, diet, and other stressors which may all indirectly impact on training and performance. Monitoring training should address the issue of session-to-session exercise intensity for individuals. This has acute implication to whether or not each session is of a meaningful intensity for different athletes. The limitation of heart rate or o ther metabolic va riables for monitoring training i s that t hey ar e task sp ecific. F or exa mple, str ength, spee d, anaerobic and technical training sessions do not evoke high heart rates and thus heart rates cannot be used to accurate ly represent th e metabolic challenge of these activities. The prin ciples o f sel f-regulation suggest t hat suitably c onstructed RP E methods of monitoring training are likely to be effective across all types of exercise. Important sel f-regulatory trai ning sk ills i nclude mental tou ghness, s elfconfidence, i mprovisational training a nd co ping st rategies t o co unteract the many obstacles blocking the path to success.

REFERENCES [1] [2] [3] [4]

Crowther, N., Athle te an d state: q ualifying for the O lympic Ga mes in ancient Greece. Journal of Sport History, 1996. 23: p. 34-43. Impellizzeri, F., et a l., U se of RPE-based training load in so ccer. Medicine & Science in Sports & Exercise, 2004. 36: p. 1042-1047. Flouhaug, C.F.J., et al., A new approach to monitoring training. Journal of Strength and Conditioning Research, 2001. 15: p. 109-115. Fleck, S ., P eriodized s trength tr aining: a critical review. Journal of Strength and Conditioning Research, 1999. 13: p. 82-89.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

96 [5] [6]

[7] [8] [9] [10]

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

[11] [12] [13] [14] [15] [16] [17] [18]

Andrew Edwards and Remco Polman Day, M. , et al ., Mon itoring exer cise intensity during resistance training using the s ession RP E scale, Journal of Strength and Conditioning Research, 2004. 18: p. 353-358. White, P., et al., Proto col for th e PACE trial: a r andomised controlled trial of a daptive pacing, co gnitive behaviour th erapy, and graded exercise as supplements to sta ndardised specialist me dical car e versus standardised s pecialist me dical car e al one for pa tients wi th the chronic fatigue sy ndrome/myalgic encephalomyelitis or encephalopathy. BMC Neurology, 2007. 7: p. 1-20. Fleck, S . and W. K raemer, The ul timate training system: p eriodization breakthrough. 1996, New York: Advanced Research Press. Stannard, S. and M. Thompson, Heart rate monitors: coaches' fr iend or foe? Sports Coach, 1998. 21: p. 36-37. Glass, S. a nd D . Sta nton, Se lf-selected re sistance train ing in tensity in novice weigh tlifters. Journal of Strength and Conditioning Research, 2004. 18: p. 324-327. Mazzetti, S., et al., The influence of direct supervision of resi stance training on s trength p erformance. Medicine & Science in Sports & Exercise, 2000. 32: p. 1175-1184. Gamble, P ., Periodization o f train ing for team s ports athletes. Strength and Conditioning Journal, 2006. 28: p. 56-66. Ratamess, N., et al., Self-selected resistance training intensity in healthy women: the influen ce of a personal trainer. Journal of Strength and Conditioning Research, 2008. 22: p. 103-111. Bannister, E. and T. Ca lvert, A sy stems model of training f or athl etic performance. Australian Journal of Sports Medicine, 1975. 7: p. 57-61. McArdle, W ., F . Katc h, and V. Katch, Exercise p hysiology: nu trition, energy an d human per formance. 7 ed . 2 010: Lippincott Williams & Wilkins. Leff, A ., Cardiopulmonary e xercise te sting. 1 986, Lo ndon: Grune & Stratton. Edwards, A. and T. Noakes, De hydration: cause o f fatigu e o r si gn o f pacing in elite soccer? Sports Medicine, 2009. 39: p. 1-13. Edwards, A., e t al., Se lf-pacing in in terval traini ng: a tel eoanticipatory approach. Psychophysiology, 2011. 48: p. 136-141. Davies, C. and M. Thompson, Aerobic performance of female marathon and ma le ultr amarathon athl etes. European Journal of Applied Physiology, 1979. 41: p. 233-245.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Monitoring and Self-Regulating Training

97

[19] Coyle, E . and J . Go nzalez-Alonzo, Ca rdiovascular d rift du ring prolonged exer cise: new per spectives. Exercise and Sports Science Reviews, 2001. 29: p. 88-92. [20] Whaley, M., et al., AC SM’s guidelines f or exer cise tes ting and prescription. 7th ed. 2006, Philadelphia: Lippincott Williams & Wilkins. [21] Borg, G., Psychophysiological bases of perceived exertion. Medicine & Science in Sports & Exercise, 1982. 14: p. 377-387. [22] Chen, M. , X. F an, and S . Moe, Cr iterion-related v alidity of the Borg ratings of perceived exer tion scale in healthy i ndividuals: a metaanalysis. Journal of Sports Sciences, 2002. 20: p. 873-899. [23] Fitzgerald, M ., Br ain training f or r unners. 20 07, New Yor k: New American Library. [24] Eston, R. and J. Will iams, Re liability of r atings of perceived ef fort regulation of exer cise intensity. British Journal of Sports Medicine, 1988. 22: p. 153-155. [25] St Clair Gibson, A., et al., The r ole of in formation proces sing between the brain and peripheral physiological systems in pacing and perception of effort. Sports Medicine, 2006. 36: p. 705-722. [26] Fitzgerald, M., Run: The mind-body method of running by feel. 20 10, Boulder, Colorado: Velopress. [27] Noakes, T., The central governor model of exercise regulation applied to the marathon. Sports Medicine, 2007. 37: p. 374-377. [28] Noakes, T., A . St Cl air Gi bson, and E. Lam bert, Fr om cata strophe to complexity: a novel model o f integrative cen tral neu ral r egulation o f effort and fatigue during exercise in humans: summary and conclusions. British Journal of Sports Medicine, 2005. 39: p. 120-124. [29] Polman, R., Elite athletes’ experiences of coping with stress, in Coping and emotio ns i n sport, M.J. J. That cher, & D. Lava llee Edito r. 201 1, Routledge. [30] Nicholls, A ., et al., S tress and coping amon g international adoles cent golfers. Journal of Applied Sport Psychology, 2005. 17: p. 333-340. [31] Haney, C. an d B . Lo ng, Coping e ffectiveness: a path analysis o f se lfefficacy, control, coping and performance in sport competitions. Journal of Applied Social Psychology, 1995. 25: p. 1726-1746. [32] Ord, P. and K. Gi jsbers, Pain thresholds a nd t olerances of competitive rowers a nd theur use of spontaneous sel f-generated pain -coping strategies. Perceptual and Motor Skills, 2003. 97: p. 1219-1222.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

98

Andrew Edwards and Remco Polman

[33] Clough, P., K. Earle, an d D. Sewell, Mental toughness: the concept and its measurement, in So lutions in sport psychology I. C ockeril, Edi tor. 2002, Thompson Publishing: London. p. 32-43. [34] Kaiseler, M. , R . Polm an, and A. Nicholls, Mental tou ghness, stress, stress ap praisal, coping and copi ng ef fectiveness in sport. Personality and Individual Differences, 2009. 47: p. 728-733. [35] Polman, R., P. Clough, and A. Levy, Personality and coping in sport: the big fiv e an d mental tough ness 2010, Nova Scie nce Pub lishers. p. 141157. [36] Crust, L. and K. Aza di, Ment al t oughness and at hletes’ us e of psychological s trategies. European Journal of Sport Science, 2010. 10: p. 43-51. [37] Baron, B., et al., The rol e of emotions on pa cing stra tegies and performance in middle and long duration sport events. British Journal of Sports Medicine, 2011. 45: p. 511-517. [38] Lander, P ., R. Bu tterly, and A. Edwards, S elf-paced ex ercise is less physically challenging than enforced constant pace exercise of the same intensity: i nfluence of complex central metabolic control, British Journal of Sports Medicine, 2009. 43: p. 789-795. [39] Albertus, Y. , et al. , Effect of dis tance feedback on pacing st rategy a nd perceived exerti on during cycling. Medicine & Science in Sports & Exercise, 2005. 37: p. 461-468. [40] Nikolopoulos, V., M. Arkinstall, and J. Hawley, Pacin g s trategy in simulated cy cle t ime-trials is based on percei ved rather than actual distance. Journal of Science and Medicine in Sport, 2001. 4: p. 212-219. [41] Paterson, S. and F. Marino, Effect of deception of distance on prolonged cycling pe rformance. Perceptual and Motor Skills, 2 004. 98: p. 10 171026. [42] Banting, L., J. Dimm ock, and J. Grove, The impact o f au tomatically activated mo tivation on exercise-related outc omes. Journal of Sport & Exercise Psychology, 2011. 33: p. 569-585.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Chapter 5

PACING FOR ENDURANCE

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

5.1. ABSTRACT The aim of this chapter is to examine the issue of pacing specifically in r elation t o endur ance. The ch apter id entifies and di scusses physiological and psychological demands o f act ivities su ch as marathon running, cy cling, triathl on and row ing. Regular training for these activities produces specifically adaptive responses with which to improve performance. These f actors are discu ssed i n addi tion to evidence-based observations o f successful paci ng s trategies in end urance events. Common pacing strategies for endurance events suggest front loaded, fast start approaches are optimal for most endurance events, other than those of e xtreme duration as, in the ear ly stages of a p erformance, t here i s relatively minor metabolic disturbance. Increasing the pace of an exercise bout i n th e presence of accumulating ne gative s ensations o f fatigue requires con siderable motivation. There fore, p sychological cop ing strategies for endurance act ivities are identified. Finall y, a practical model for devising and monitoring training via a self-paced programme is presented and explained. This can be adapted to the specific requirements of the endurance performer.

5.2. INTRODUCTION The ability to sust ain physical work fo r prolonged peri ods underpins successful performance in many sports, most of which have been deliberately designed to maximally tax the physical limits of the participants. In endurance activities, t he abil ity to tolerate phy sical dis comfort fo r prolonged periods is

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

100

Andrew Edwards and Remco Polman

vital to succe ss an d a s such , we have sug gested in previous chapters of this book th at this m ay be accomplished through th e dev elopment of selfregulatory training skills (see chapter four). Many nutritional, phy sical, psy chological, or techni cal interventions can also aid performance and each may be broadly grouped as 1) augmenting the physical attributes of the pe rformer (e.g. by direct physical training or using a technical innovation), 2) im proving the performer’s m ental s tate (e.g. psychological ski lls trai ning), or 3 ) improving regulat ory p hysiological processes (e.g . nutriti onal supplem entation). Viewing th e human from a psychophysiological per spective, it i s possible to see how these factors interrelate [ 1]. Fo r ex ample, it has been s uggested that conducting tr aining in a state of carbohydrate depletion m ay p roduce po sitive performance outcomes [2, 3] despite intuitively sounding like a very bad idea. Performing endurance training wi th minimal m uscle glycogen is un likely t o lead to qual ity performance outco mes and if over-used could lead to a de training ef fect; however, i f ad opted as an o ccasional training practice it may b e us eful from both psychological and physiological perspectives. The volu ntary d enial or d ebilitation of a me tabolic subs trate such as carbohydrate would r educe r esidual mu scle glycogen stor es an d r equire a mental c oping r esponse as a means t o i mprove factors s uch as mental toughness (see ch apter fo ur). Additionally, v oluntarily performing end urance exercise in a state of glycogen depletion not on ly develops mental toughness, but al so encourages the body to up regulate f at metabolism while g lycogen stores ar e diminished [ 2]. Consequently, the res ponses of the human body to endurance ex ercise ar e multi -dimensional an d th is chapter co nsiders fact ors pertinent to bo th physiological and psy chological perspectives bef ore combining into a practical psychophysiological training model specifically for the development of endurance capabilities.

5.3. PHYSIOLOGY OF ENDURANCE The critical determinant of success for all endurance-based activities is the ability t o susta in a high ra te of work fo r p rolonged periods [4]. End urance trained athletes are better able to sustain high levels of physical effort powered from aerobic e nergy pa thways tha n no n-athletes and co nsequently [5 ] p lace less d emand on the body’s limited body stores of muscle gly cogen. Metabolism of gl ycogen fa cilitates m ore ra pid ATP re generation than f rom

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Pacing for Endurance

101

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

lipid [ 6] an d the pr eservation of glycogen fo r t imes o f n eed is o f pr ime importance as a conserving/protecting mechanism [7]. An overview of e nergy metabolism from carbohydrate and lipid sources is shown in Figure 5.1.

Figure 5.1. Summary of the main pathways of energy metabolism using carbohydrate and lipids as energy sources. Through the reactions of glycolysis, carbohydrates are broken down to pyruvate under aerobic conditions and lactate under anaerobic conditions. The anaerobic process of glycolysis produces limited ATP, but does so rapidly. In response to slower demand for energy (aerobic exercise), carbohydrate converted to pyruvate is further converted to acetyl CoA and then completely oxidized in the tricarboxylic acid (TCA or Krebs’) cycle within mitochondria. Lipids are hydrolysed to fatty acids and glycerol. Glycerol can enter the glycolytic pathway, while fatty acids are converted via beta-oxidation to acetyl CoA and subsequently enter the TCA cycle. The TCA cycle produces ATP, as does the electron transport chain which removes electrons from hydrogen. In this process, oxygen accepts hydrogen to form water.

It wou ld b e easy to con clude t hat carbohydrate availability si mply limits performance by facilitating higher power outputs until muscles are completely depleted of glycogen. Thereafter, the athlete would be forced to slow down to facilitate resynthesis of ATP from the slower energy producing substrate of fat

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

102

Andrew Edwards and Remco Polman

[6]. Such an observation is an alogous to r unning a c ar unt il t he f uel t ank is empty. However, most pe ople ar e abl e to lo ok a t the f uel gauge of their car and behaviourally av oid this o ccurring. Brain r egulation of ex ercise su ggests we are able to prevent running on empty b y l istening to afferent sensory information (whether or not we are consciously aware of this) and thus avoid the potential catastrophe of running out of fuel [8]. According to th e principles of conscious brain regulation, the body stores of glycogen should never fully deplete during exercise. This has s hown to be the ca se in several s tudies whereby individuals pace themselves in r eceipt of afferent s ensory feedb ack alerting t hem to r eductions in metabolic stores [ 9, 10]. The brain therefore adjusts pace to properly manage the fuel stores across the exe rcise bout so th ey a re not maxim ally d epleted. Thi s ca n be seen in practical oper ation d uring endurance time t rial p erformances as carbohydrate loading has frequently been demonstrated to result in greater pace compared to a placebo condition. However, at the conclusion of exercise, the residual stores of glycogen are not diff erent bet ween loading an d placeb o condition, neither of which results in maximal muscle glycogen depletion [10]. The trajectory of power out put reflects the avai lable substrates, su ch t hat th e con dition w ith greater i nitial intra-muscular stores of h igher energy fu el usually results in a better pe rformance. This s imply r eflects eff ective pa cing via muscle-neural communication in the sub awar e kn owledge of gr eater metabolic fuel [7]. Sensations of fatigue (i.e. m etabolic war ning sign s) occur prior to gl ycogen depletion. T his tends to s upport th e th eory of a conserving mechanism by which s ensory feedback in forms the b rain of gl ycogen a vailability amongst other variables. All successful endurance tr ained at hletes obviously possess good aerobic fitness. An in dividual’s oxy gen uptake respons e to a grad ed, in cremental exercise test is a reasonable predictor of endurance performance [4] and this is commonly referred to as a test of maximal aerobic power ( V⋅ O2 max) [11]. The capacity of t he i ndividual for en ergy tr ansfer r equires the i ntegration of t he respiratory, car diovascular, an d neuromuscular sy stems f or the p urpose o f 1) up take, 2) transport and 3) utilization of O2. This facilitates improved oxygen uptake ( O2) at the lungs, gr eater tr ansport of O 2 i n the blood t o th e working muscles, and more effective O 2 extraction from the blood as it reaches muscle [6]. Improvements to V⋅ O2 max can b e obser ved in the c ardiovascular sy stem by means of increased cardiac output during exercise [12, 13]. Cardiac output is the product of heart rate and stroke volume and as the maximal achievable heart rate does not change with training [13], the potential to improve maximal

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Pacing for Endurance

103

cardiac outpu t is cons equent to increases in beat-to-beat eff iciency via stroke volume augm entation. This oc curs as a l ong ter m adap tation to endurance training, by which the heart becomes more efficient to pump greater quantities of oxygenated blood around the body with each beat. Therefore, to achieve a given cardiac output, the trained heart grows in efficiency and no longer needs to beat with the same high frequency of an untrained heart which pumps lower volumes of oxygen carrying blood with each beat [6]. The co ncept of V⋅ O2 max has b een studied extensively to gau ge it s importance to pe rformance a nd a high V⋅ O2 max ( e.g. > 70 ml/kg/min) is commonly assoc iated w ith succ ess in endurance events [ 5]. Howev er, this measurement does not have a high correlation among homogenous populations of endurance athletes. For example, several studies have demonstrated a wide range of endurance performances among populations with similar V⋅ O2 max or alternatively, equivalent p erformances wit h dissi milar V⋅ O2 max (e .g. 5 0-80 ml/kg/min) [14]. This is largely to be expected as the aim of endurance sports performance is to win a race, competition or complete a specific task. The aim is not t o i mprove V⋅ O2 max and altho ugh this is a by -product of enhanced endurance capab ilities, n umerous studies h ave shown that V⋅ O2 max do es not vary to a l arge exte nt with tr aining [15]. As discussed in cha pter three, i t is also per haps na ive to assume tha t V⋅ O2 max repr esents a true phy siologic maximum as w e ha ve seen p reviously t hat pe rformers do no t fu lly t ax physiological sy stems [16, 17]. Therefore it is more suitable t o refer to V⋅ O2 max as ei ther V⋅ O2 peak o r V⋅ O2 max ( maximum v oluntary effo rt). As a consequence, although the maximal ability to take up and use oxygen during exercise ( V⋅ O2 max) is one of the parameters explaining successful performance in prolonged exercise, performance is most likely dependent upon a co mplex blend of contr ibutions from a nu mber of p hysiological f actors, all subject to regulation by the brain. Metabolic changes occur with endurance training in th e muscles to allow for the efficient use of available oxygen. These adaptations include: increased number and size of mitrochond ria [18], increased ATP production, decreased amounts of lactic acid, increased triglyceride content, increased energy derived from fa tty acid, lower glycogen us age in th e mu scles dur ing e xercise, increased enz yme a ctivity for ener gy turnover, a nd improved efficiency in utilising oxygen from the blood supply [19]. Endurance tr aining in creases th e nu mber and size of th e mitoch ondria within muscle fibres for aerobic production of ATP and this is accompanied by greater concentrations of ox idative e nzymes to up r egulate metabolic

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

104

Andrew Edwards and Remco Polman

reactions, a nd incr eases to the de nsity of capillaries supply ing oxygenated blood t o mus cle [6, 20]. There i s also an ass ociation in the time cou rse between the ch anges in oxidative enzyme activities and improvement in V⋅ O2 max [4, 21]. The efficiency with which the c hemical ener gy of ATP hydrolysis is converted to p hysical work depends g reatly on muscle factors. Ty pe I ( slow twitch) fibres have been shown to display greater mechanical efficiency. Elite endurance ath letes t ypically possess a predominance of type I m uscle fib res and these are more mechanically efficient at the velocities of distance running [18, 22]. It is t herefore no t s urprising that elite end urance athl etes typically possess a higher percentage of type I muscle fibres, given that they are more efficient. Although ty pe I muscle fib res i n u ntrained humans possess h igher mitochondrial density compared with type II fibres (fast twitch), it is important to no te that with intense, sustained cardi ovascular training, mitochondrial activity can be increased in both fibre ty pes [ 23]. Thus, w ith endurance training over many years, the main f unctional a dvantages of ty pe I fibr es appears to be efficiency and a greater ability to oxidize fat. Mechanical e fficiency doe s not oc cur spontaneously, it is ac quired through p rior experience an d d edicated pract ice to improve neuromuscular coordination. A natural tendency to f avour genetic dispositions for exercise is evident in th e events or sports indiv iduals tend to select for part icipation. Equally, while per forming acti vities, m ovements r eflect individuals’ in herent abilities although it is difficult to discern whether this is consequent to unique morphological char acteristics, or whet her char acteristics be come c onsequent to movements through specific training [24]. An interesting study by Hansen et al. [ 18] sought to investigate w hether athl etes display a na tural pr eference for movement s trategy based on their mus cle char acteristics. In that investigation, subjects wer e requested to s elf select an opt imal cycling pe dal rate so to attain at p ower output e quivalent to 70% o f their m aximal aerobic power. Perhaps unsurprisin gly, su bjects with hig her levels of type II (fast twitch) muscle fibres self selected faster pedal rates to attain the target power output while t hose with greater t ype I (m ore O 2 efficient) mus cle fibres selected slower rates. Th is study neatly demonstrated t hat athletes tend to sel f select m ovement pat terns closely related t o their natur al dis position for exercise. Other f actors t hat influence t he metabolic re sponses to exercise i nclude training stat us, d iet, environmental temperature, a nd gende r [ 4, 2 1, 2 5-27]. These all combine to produce improvements in exercise efficiency, attenuation of lactate and H+ concen trations during exercise, diminishing the reliance on

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Pacing for Endurance

105

limited body fuels such as glycogen and reducing the need for aggressive sweating to evoke evaporative cooling as a means of counteracting excessive heat production.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

5.4. PSYCHOLOGY OF ENDURANCE At the elite level, long d istance runners complete training loads in ex cess of 1 50 km each week wh ich not only p lace significant phy sical a nd psychological de mands on th e athlete but may also pl ace strain on th eir personal lives. Sin ce the 1980s, participation in mar athon ru nning by recreational athletes has also increased dramatically[28]. The motives for this group of r unners ar e as sociated to so me e xtent w ith w inning but more generally with the ach ievement of p ersonal goals, health, s elf-esteem and affiliation [29]. Acc umulative ru nning tim e means that athletes ha ve a significant amount of thinkin g t ime (more than 2 hours during a m arathon event) and during this perio d, ath letes p rocess internal and ex ternal information while also maintaining concentration for ra cing. In the marathon, it is ge nerally assume d t hat athl etes hav e to be aware of th eir own physical limitations to pace their race correctly. As alluded to in chapter two, differences in personality have been reported between athletes. Much of this research started with long distance runners [30] and th ere is ev idence that su ccessful athlete s hav e certain de sirable psychological ch aracteristics. F or exa mple, long d istance r unners have been found to be more emotionally stable, less introverted and neurotic and have a more d esirable mental h ealth profile ( so called ‘ iceberg’ pr ofile; [ 30]). The y have also been reported to have lower l evels of depression and anxiety, with concomitant higher levels of vigour [31, 32]. Finally, marathon runners score higher in ac hievement mo tivation a nd ar e mor e in trinsically m otivated [33]. Since personality traits are assumed to be relatively stable over time this would indicate th at these psy chological factors wou ld at le ast, to some e xtent, b e predictors to both running participation and success. With regard to th e latter, the d esirable psy chological char acteristics ar e more evident in s uccessful athletes in comparison to less successful athletes [34] and they are more likely to allow athletes to cope with the physical and psychological stressors innate to endurance activities. Although some of the psychological factors outlined above are modifiable, there are other ways to hel p athletes with the stress associated with endurance activities. A nu mber of st udies have examined th e cogni tions of endurance

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

106

Andrew Edwards and Remco Polman

athletes during their t raining and competi tion. These studies hav e gen erally investigated how the at hletes cope with t he extr eme phy sical ( pain and discomfort) a nd psychological d emands of th eir e vents (e .g. [35, 36]. Successful athletes, in t his respect, will use either association or dissociation as co ping strategies durin g endurance ev ents [30, 35 , 37 ]. Association is th e monitoring of p hysical or b odily sen sations related to run ning (e.g. body awareness and breathing) and tactics (including running pace). Dissociation is the diversion of attention away from unpleasant physical sensations. A number of sub-categories have been i dentified for dissociation. Goode and Roth [37], in the development o f the Though ts During Ru nning Scale (TDRS), distinguished between external su rrounding, in terpersonal relatio nships, daily events, and s piritual r eflection. I t has also been suggested that associative (task-relevant) an d d issociative ( task-irrelevant) c ognitions ha ve b oth an internal and e xternal dimension [38]. Ex amples of inte rnal asso ciative cognitions wou ld b e related to brea thing, pe rspiration and ot her b odily functions. Internal di ssociative co gnitions could incl ude daydreams, f antasies and philo sophical musing. Alt ernatively, ex ternal associative cognitions may be related t o strategies or spl it times, wh ile extern al di ssociation cognit ions could involve thoughts on the enviro nment, s cenery o r attention t o o ther athletes. The s uggestion has be en ma de tha t th e ter m diss ociation in a sports context would be inappropriate because of its use in clinical settings. Although both clinical patients and athletes use dissociation to escape unpleasant stimuli in the environment, athletes generally have control over this cognitive strategy and some have suggested t hat the te rms internal ver sus external cognitive strategies should be used (see [39] for a review). In his article ‘ the mind of the marathoner’, Morgan [35] o utlined that successful marathon runn ers are more l ikely t o use asso ciative co ping strategies. Based on the ex amination of 24 Un ited States of America world class runners he found that these elite athletes were in tune with their bodies and monitored p hysiological se nsations of exer tion such a s respiration, temperature, heaviness in their legs, hydration, muscular pain, and abdominal sensations whilst running. On the whole the lit erature supports the notion that associative coping strategies result in faster running performance. Associative coping str ategies c an be used t o op timize efficiency and determine pac e an d there is so me e vidence that associative coping s trategies are r elated to r unning economy. I n a stu dy of 18 co mpetitive male dis tance runners it w as fo und that running economy was r elated (r = - .50) to self attention. Th at is r unners who habitually dir ected att ention inwards ha d th e

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Pacing for Endurance

107

most economical running style [40]. An in ward focus would allow the runner to be more sensitive and deal appropriately with muscular tension which might interfere wit h per formance or eng age the u se of othe r associ ative co gnitive strategies aimed at improving running economy. Running speed is a f actor wh ich moderates th e relationship between running performance and the us e of associative coping stra tegies. Tamm en [41] i n a study of e ight elite run ners req uired to run at different sp eeds, showed th at as running pace in creased the a thletes reported mor e use of associative rather than dissociative coping strategies. The runners in the study found it diffi cult to use internal cues to regulate th eir pace at lower speeds because they were not used to running at such low running velocities. In these situations they relied on external feedback to regulate their pace (e.g. listening to experimenter). At maximum pace, which was close to training or race pace, the r unners us ed their bo dily sensations, breathing and cadence to deter mine their performance. The stage of a running event might also be a factor which influences the use of associative or di ssociative coping strateg ies. Disso ciation coping strategies are used early in a race and associative strategies towards the end of a r ace [ 36]. A t th e end of a race t he runner will suffer fr om reduced energy resources and at thi s s tage, ass ociative coping wo uld al low f or be tter monitoring and regulation of pace and therefore optimize performance. Non-elite runners have been found to use a n umber o f psychological strategies whic h i ntentionally distract them fr om the often uncomfortable sensations associated with intense p hysical e xertion. Such s trategies inc lude listening to music, a dhering t o pr e-race str ategy, cond ucting c omplicated mathematical calculations, or imaging pleasant past experiences. Morgan [35] in hi s classic paper co nsidered d issociative strategies to be dangerous with athletes more likely to hit the proverbial ‘wall’ and increase the probability of injury by ignoring important afferent ( warning) signa ls. Ho wever, although elite ma rathon ath letes ap pear m ainly to us e associative coping s trategies during competition, many use and prefer dissociative coping strategies during training r uns [39]. A pos sible exp lanation f or th e pr eference of diss ociation during training runs is that these tend to be conducted at lower pace. The ‘wall’ ( often called ‘ bonk’ by cy clists and tri athletes) i s a p articular psychological p henomenon in endurance sp orts which i s perhaps best explained as a neural anticipatory (protective) response preceding a necessary change of the domin ant ener gy sup ply fr om glycogen t o lipid. Th is occ urs after approxim ately 3 0 k m of running. Up t o 50% of r unners e xperience the wall ( e.g. [28]) with a higher pr evalence in males in comparison t o females.

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

108

Andrew Edwards and Remco Polman

The us e of associative c oping str ategies has b een s hown t o pr otect athl etes from experiencing the wall [30]. In a more recent study by Buman et al. [28] the c ognitive, behavioural, an d af fective characteristics as we ll as th e coping responses of hitting the wall w ere examined q ualitatively in a sam ple of 5 2 marathon runners of d ifferent ab ilities. This study highlighted th e notion that the wal l is a multi-facet ted phenomenon t hat consists of the i nteraction between physiological (cramping, di et/hydration, gen eralized fatig ue, illn ess, pain, leg-relate d fatigue, ca rdio-respiratory, senso ry dis tortions), behav ioural (loss o f running for m, pace d isruption, runnin g difficulty, tunnel vis ion), cognitive (anxiety , c hanging goal s, confu sion, mental battle, trouble focussing), affect ive (cr ying, discour agement, frustrati on, irr itability, s hame) and motivational (decreased motivation, desire to quit or walk) characteristics. Although t he runners us ed associative and dis sociative coping str ategies, not all their cop ing responses could be class ified u nder t his higher o rder distinction. Surprisingly a significa nt n umber o f participants (30 %) h ad no strategies to cope wi th hi tting the wall (not sur e what t o do; not hing works; just let it happen). A lso, the run ners used mental r eframing ( race segmentation; p erformance j ustification) and willpower ( e.g. j ust keep running; tough it out; push through it) to cope with it. An important practical implication from this research is that runners need a large repertoire of coping strategies to deal effectively with the different interacting elements associated with hitting the wall. For example, to deal with the physical stressors could be through the use of associative strategies whereas the cognitive or motivational aspects might be be st dealt with throug h sel f-regulatory stra tegies like dissociation, mental reframing and self-talk [28, 42]. A ver y common di ssociative te chnique us ed by endurance athletes is music. F indings suggest that in p articular s ynchronous music has e rgogenic properties and that individuals feel less t ired whils t r unning or cy cling to music and w orkout times ar e increased up t o 20% [ 43]. This is also tr ue f or clinical popu lations. Ch ronic obs tructive pu lmonary disease (COPD) p atients do more wor k on the treadmill wh en l istening to music and report ed lower maximal RPE levels [44]. This would suggest that music diverts attention from fatigue as w ell a s altering pe rception of ho w ha rd an in dividual is working. Music can also increase positive mood and decrease negative mood and alter psychomotor arousal. As such, it can b e used as a s timulant or psy ching-up strategy, or e ven as a r elaxation tool pr ior to a nd during phy sical exercise depending on the characteristics of the music [43, 45]. Musical preferences are very individual and selection of the right stimulus may take prior planning to ensure that t he music chosen w orks as inten ded. A goo d example i s th e

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Pacing for Endurance

109

Ethiopian Olympic long distance winner Haile Gebreselassie. He enjoys music and has previously indicated it gives him energy, while provid ing him with a rhythm to fit with his r ecord pa ce. Alternatively, music can als o hinder performance; the Engli sh f ormer Olympic d ecathlon w inner Dal y Thompso n apparently found music an unwanted distraction.

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

5.5. PACING AND STRATEGY FOR ENDURANCE The ability to a ccurately self-pace an endurance e xercise b out i s an important feature of race and time trial performances [27, 46]. However, selfpaced exer cise bouts are know n to de monstrate co nsiderable intra-trial fluctuations of p ower outpu t, [47 ] an d this may have led to a misconception that they are unreliable. It is perhaps due to the variability of power output in self-paced exercise that sc ientists have t ended to develop l aboratory ex ercise protocols i n which par ticipants are requ ired to respo nd to externally imposed/fixed w ork ra tes. T his i s o f c ourse a co mpletely a lien form of exercise compared t o r acing and is pr obably the mo st o bvious r eason why protocols such as thos e us ed to tes t V⋅ O2 max do no t accurately re flect the determinants of endurance race performances. In race situations, competitors anticipate and decide how best to approach the race in the knowledge of the race duration, the circumstances of the event and their own capabilities. To som e extent, athletes respond (dynamically) to the race circumstances as these unravel around them, while still adhering to an overall performance strategy [48]. Interestingly, a r ecent study identified that pacing i n r esponse t o an e xternally imp osed protocol is considerably har der than conducting exactly the same activity when self-paced [47]. Consequently, fluctuations i n wor k output during exercise pr obably represent m eaningful changes of pac e, mediated by the transient s ensations of well being (i.e. feeling good or bad fro m moment to moment). Nevertheless, variable p acing strategies hav e not always b een sh own t o be au gment performance a mong well-trained endurance run ners, prob ably beca use their well es tablished and intrinsic sense of pacing [49, 50]. This is less likely to occur in less automated activities such as race or competitive situations. In most solo competition timetrials, fluctuations of pace may be driven by sensations of wellness (or absence of negat ive em otions), while i n a race with fel low competitors, th ey m ay represent unexpected and externally forced work rate changes with additional

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

110

Andrew Edwards and Remco Polman

self-mediated changes (such as down-regulating effort as a coping mechanism) in r esponse to s ignificant metabolic disturbance wh ere, when , or if poss ible [51]. Externally paced exer cise do es no t facilitate deviation fr om a pr escribed work outp ut and s imply drives a ll phy siological sy stems to a sta te of discomfort which at some point will dev elop into a level of i ntolerance which in turn will provoke the athlete to decide to stop the exercise bout [17]. This of course does not oc cur in a r ace, b ecause r aces ar e se lf-paced and th e competitors are able to decide how to properly pace themselves to get the best out of their per formance. Racing a nd competitive s ituations are therefore prime examples of brain regulation controlling performance. Consequently, a number of psychological factors, like pre-race state anxiety or self-confidence will impinge on determining pacing. A race, in this respect, is usually judged on the final performance outcome, not on the length of time taken to reach a maximal p lateau in a m easured physiological variable and d isplayed o n a computer screen. That would be a very dull race. The outcome of all Olympic endurance events has been estimated to occur at intensities above 85% V⋅ O2 max [20] which means each event requires a high level of ener gy metab olism and cons iderable m otivation t o sustain exercise intensity. Of co urse, p articipation at events s uch as t he Oly mpics i s a motivating factor in itself, but data t rends have emerged in recent years which enable comparisons of how hig h performance athletes determine pacing plans for particular events. In chapter two, numerous categories of pacing strategies were identified which m ay be ad opted by athletes to op timize perfor mance. There is n o ‘ one-size f its a ll’ model of pacing f or e ndurance events as each model requires specific ph ysical a ttributes, could be a ffected by the race circumstances, and of cour se, be influenced by th e d uration of t he ev ent. However, o utcomes fr om mo st en durance bas ed activities generally demonstrate success is consistent with utilizing front loaded strategies and/or ‘U’ shaped pacing i.e. a relatively fast start and a final end spurt [52-54]. This makes practical racing sense as the accumulated negative sensations of fatigue in t he middle-latter s tages of a r ace diminish th e des ire to pr opel t he b ody towards a sta te of greater physical disc omfort, unle ss t he event is o f particularly mea ningful i mportance. In the e arly s tages of a r ace, hi gh wor k outputs can be attained while negative aff erent s ensory i nformation is relatively minor. These sensations of course accumulate during a race, but by that stage considerable work has been accomplished. An ex ample of pa cing s trategies in pr actical oper ation during en durance events may be observerd in Tr iathlon [ 55]. Tr iathlon r aces vary in d istance

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Pacing for Endurance

111

with 1) ‘Sprint’ events (7 50 m sw im, 2 0 km b ike, 5 km ru n), 2) t he ‘Short Course’ commonly referred to as "Olympic” (1.5 km swim, 40 km ride, 10 km run), 3) the ‘Long Course’ commonly referred to as th e Half Ironman (1.9 km swim, 90 km r ide, 21.1 km r un, and 4) the U ltra Distance (3.8 km s wim, 180 km ride, and a marathon: 42.2 km run), known as the Ironman distance. Le Meur et al. [56] identified that all of the 136 triathletes competing in an international Oly mpic dis tance event adopted a ‘‘ positive p acing strategy’’ through the running phase. During this race, the first of the four laps was run 10.0% faster than the three remaining laps. However, it is not always possible to discern from thes e dat a wh ether or not a fi nal end s purt exists as triath lon laps are lo ng and en d s purts relative ly brief. Nevert heless, Le Meur’s observations ar e broadly similar to thos e of V leck et al. [ 57] who neatly demonstrated triathlon pacing across the different stages of Olympic distance racing among elite ITU competitors. The s wimming stage of triathlon (Figure 5.2) demonstrates a substantially faster pace for the first 200m compared to all other sectors of that stage. This could suggest that the athletes are seeking to maximize t heir physiologic performance while fr esh; h owever, a much more likely explanation lies in seek ing optimal race po sition and s trategy. In triathlon, the swimming s tage commences as o ne large c ohort a nd the f irst 200m is la rgely a sc ramble a s at hletes s eek cle ar w ater a nd separation f rom other racers. Field-based r esearch h as shown that w ell-trained tri athletes perform the cycle p hase o f th e Ironman tr iathlon at ap prox 80—8 3% of maximum heart rate and 55% of peak power o utput [ 58]. Ho wever, cy cling pace is la rgely consequent to t he ‘pack’ pace and an even pacing s trategy is commonly observed in this st age of t riathlon (Figure 5.3). Each of th e thr ee sta ges in triathlon are obvio usly part of the same race performance and alth ough there may be occasional deviations of pace due to tactical considerations i.e. seeking to quickly transit from bike to ru nning, p acing i s perfo rmed in re lation to completing t he collective e vent (triathlon) a nd no t si mply eac h stage. Th e running stage is t he f inal element for the tr iathlon and Vl eck d emonstrated a common reverse ‘J’ shape triathlon running where a final end spurt is clearly observable a s th e co mpetitors acc elerate t owards th e finish despite considerable physical sensations of fatigue (Figure 5.4).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

112

Andrew Edwards and Remco Polman 1.45

Sector speed (m/s)

1.4

1.35

1.3

1.25

1.2

1.15 0 0-222m

222-496m

496-693m

693-915m

915-1189m

1189-1385m

Race sector (m)

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 5.2. Average speeds (m/s) (± SD) for swimming stage of the Lausanne 2002 ITU World Cup triathlons (n=68 males). Original drawing from previously published data [57].

Figure 5.3. Speed (average±S.E. (km/h) over each bike lap of ITU male Triathlon by pack number to which the athletes belonged (5 packs). All packs except pack 5 (∗) adopted an even pace strategy. Pack 5 dropped from the pace at lap 2 and worked to rejoin the even pacing strategy of the whole group from laps 3-6. Taken with permission [57].

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

Pacing for Endurance

113

Copyright © 2012. Nova Science Publishers, Incorporated. All rights reserved.

Figure 5.4. Run speed (±S.E) for three packs of ITU World Cup male triathlon competitors. Although the running stage is the final phase of the triathlon, a fast start and final end spurt of speed is evident. This would not occur if athletes simply ran to exhaustion without a means of self-regulating performance. It is a pacing response to manage effort effectively across the entire triathlon, thus retaining energy for the final stage. Taken with permission [57].

In other endurance events such as rowing, elite competitive 2000 m races take 3 30–460 se conds t o complete [ 53]. I n t hese events, it is tactically a nd psychologically advantageous t o gain pl acement at t he f ront of t he ra ce b y increasing effort at the sta rt (F igure 5.5). This allows the r owers to look backwards do wn the course, so to s trategically mon itor the position of ot her boats and react to any sudden advances from other crews, while also allowing them to av oid the wake (wat er disr uption) of other b oats. Inexperienced rowing crews occasionally overestimate their physical conditioning and set off at a pace that is too fast, but the consequences of this miscalculation are rarely repeated with gain ed ex perience [53, 54]. Interestingly, positiv e pacing strategies in rowing are also evident in dry land ergometer training (admittedly to a l esser extent) su ggesting that 1) rower s t rain to race and 2) that thi s i s probably d ue to the ad vantages of working harder wh en negative afferen t sensations are less severe in the early stages of the bout (Figure 5.5).

Pacing in Sport and Exercise: A Psychophysiological Perspective : A Psychophysiological Perspective, Nova Science

114

Andrew Edwards and Remco Polman

*Significant differences between the two groups (p