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These include the games of association football, the rugby codes union and league and the national codes American, Australian and Gaelic.. He is President of the World Commission of Scie

Science and Football VI

Science and Football VI showcases the very latest scientific research into the variety

of sports known as football These include the games of association football, the rugby codes (union and league) and the national codes (American, Australian and Gaelic) The book aims to bridge the gap between theory and practice in football studies and presents important new work in key areas such as:

Thomas Reilly is Director of the Research Institute for Sport and Exercise Sciences

at Liverpool John Moores University He is President of the World Commission

of Science and Sports and Chair of the International Steering Group on Science and Football

Feza Korkusuz is Director of the Medical Centre and Chair of the Department of

Physical Education and Sports at Middle East Technical University, Ankara, Turkey

He is corresponding editor for Clinical Orthopaedics and Related Research and is on the International Education Board of Technology and Health Care Journal.

The papers contained within this volume were first presented at the Sixth World Congress on Science and Football, held in January 2007 in Antalya, Turkey

Science and Football VI

The Proceedings of the Sixth World Congress on Science and Football

Edited by

Thomas Reilly and

Feza Korkusuz

First published 2009

by Routledge

2 Park Square, Milton Park, Abingdon, Oxon OX14 4RN

Simultaneously published in the USA and Canada

by Routledge

270 Madison Ave, New York, NY 10016

Routledge is an imprint of the Taylor & Francis Group, an informa business

© 2009 Thomas Reilly and Feza Korkusuz, selectuion and editorial matter; individual chapters, the contributors

All rights reserved No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers.

British Library Cataloguing in Publication Data

A catalogue record for this book is available from the British Library

Library of Congress Cataloging-in-Publication Data

A catalog record for this book has been requested

ISBN10: 0–415–42909–9 (hbk)

ISBN10: 0–203–89368–9 (ebk)

ISBN13: 978–0–415–42909–2 (hbk)

ISBN13: 978–0–203–89368–5 (ebk)

This edition published in the Taylor & Francis e-Library, 2008.

“To purchase your own copy of this or any of Taylor & Francis or Routledge’s

collection of thousands of eBooks please go to www.eBookstore.tandf.co.uk.”

ISBN 0-203-89368-9 Master e-book ISBN

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vi Contents

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l Bo KRiSTeNSeN ANd T Bull ANdeRSeN

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10 Kinematic analysis of high-performance rugby props

m SAyeRS

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12 ground reaction force of a drop jump on different kinds of

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Part III

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15 enthesis pain and height growth velocity curve in junior high

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17 A comparison of injury in professional and non-professional male

F le gAll, c cARliNg ANd T Reilly

Contents vii

18 The effect of a succession of matches on the activity profiles

K odeToyiNBo, B WooSTeR ANd A lANe

19 effects of whole-body vibration and PNF stretching on

the flexibility and range of movement in elite Australian

Part IV

20 heart rate and match analysis of Finnish junior football players 119

T VANTTiNeN, m BlomqViST, h lehTo ANd K hAKKiNeN

21 influence of age, maturity and body dimensions on selection

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ANd N mimouNi

22 chronological versus skeletal bone age in schoolboy footballers 132

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23 A cross-cultural comparison of the participation histories of

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24 Physical loading, stress and recovery in a youth soccer

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25 differences in muscularity of psoas major and thigh muscles

in relation to sprint and vertical jump performances between

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26 Relationship between the ability to repeat sprints and maximal

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29 influence of playing in the european champions league on

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30 deceleration and turning movements performed during

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31 comparative analysis of the high-intensity activity of soccer

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33 Activity profile, heart rate and blood lactate of futsal referees

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34 Analysis of actions ending with shots at goal in the Women’s

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J KuRoiWA, i KAmeyAmA, m KuRoSu, T iToh, m yAmAdA,

K KomATSu, T TSuBAKihARA, i WATANABe ANd y ueNo

Contents ix

36 match activities and fatigue development of elite female

P KRuSTRuP, h ANdeRSSoN, m mohR, m BRedSgAARd RANdeRS,

J mAJgAARd JeNSeN, m zeBiS, d KiRKeNdAl ANd J BANgSBo

37 diachronic analysis of interaction contexts in the

J cASTellANo PAuliS, A PeReA RodRíguez ANd

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38 The impact of individualism on the outcome of penalty

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39 match analyses of Australian international female soccer

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40 Performance profiles of soccer players in the 2006 ueFA

champions league and the 2006 FiFA World cup tournaments 229

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Part VI

42 Thermoregulatory response to base-layer garments during

B c RoBeRTS, T WAlleR ANd m P cAiNe

43 The impact of pre-cooling on soccer-specific exercise

N d clARKe, B dRuST, d P m mAclAReN ANd T Reilly

44 effect of leg cooling at half-time breaks on performance of

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h hASegAWA, S.iShizAKi ANd T yodA

R mARTíNez-SANToS, A BlANco, F J SÁNchez ANd A loS ARcoS

A J couTTS, A c SiRoTic, c cATTeRicK ANd h KNoWleS

48 development of an offensive evasion model for the training

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K.BAll

50 effects of hypertrophy and a maximal strength training

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51 intermittent high-intensity drills improve in-seasonal

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52 The effects of strength training and practice on soccer throw-in

g m S de cARNyS ANd A leeS

A hulToN, T FoRd ANd T Reilly

54 The effect of short-term intense soccer-specific exercise on

T RoSTgAARd, F m iAiA ANd J BANgSBo

Contents xi

J BANgSBo ANd P KRuSTRuP

56 Physiological responses to playing futsal in professional players 331

c cASTAgNA, S d’oTTAVio ANd J c BARBeRo ÁlVARez

Part VIII

57 The reliability of a repeated sprint test during simulated

A c SiRoTic ANd A J couTTS

58 Validity of a group intermittent high-intensity test for repeated

J c BARBeRo ÁlVARez ANd c cASTAgNA

59 match performance and yo-yo iR2 test performance of players

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ANd P KRuSTRuP

60 Performance on two soccer-specific high-intensity intermittent

m SVeNSSoN, P coNWAy, B dRuST ANd T Reilly

61 Seasonal changes in intermittent exercise performance of

soccer players evaluated by the yo-yo intermittent recovery

F m iAiA, T RoSTgAARd, P KRuSTRuP ANd J BANgSBo

62 comparison of physiological profiles of soccer players in

A K emRe, A yildiRim, Ş çiçeK ANd F KoRKuSuz

63 A comparison of skinfold thickness measurements and

dual-energy X-ray absorptiometry analysis of percent body

J WAllAce, m mARFell- JoNeS, K geoRge ANd T Reilly

xii Contents

64 Physiological profiles of soccer players with respect to playing

A yildiRim, A K emRe, F KoRKuSuz ANd Ş çiçeK

65 criterion validity of an intermittent futsal-specific

67 Adaptation of ‘Self ‘and ‘other’ versions of the Revised Power

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71 emotions at the penalty mark: an analysis of elite players

g JoRdeT, m T elFeRiNK- gemSeR, K A P m lemmiNK ANd

Contents xiii

73 Sleep, pre-game fatigue, and game performance in female

V mARTiNez ANd e coyle

74 Sport motivation and self-efficacy in American football players 424

m çeliK ÖRücü ANd S meTiN cAmgÖz

h hoRiNo

76 The effect of memory recall on perceptual-cognitive skill in

J Bell-WAlKeR ANd A m WilliAmS

77 The microstructure of effective practice: the nature of the

i S yATeS ANd A m WilliAmS

78 The microstructure of practice in soccer: a comparison of

i S yATeS ANd A m WilliAmS

Part X

R T STeFANi, R PollARd ANd A SecKiN

80 FiFA provisions on government interference in administration

of national football federations: hindrances to full compliance

e olATuNde moRAKiNyo

81 Research informing practice: implications of rule changes to

d A o’coNNoR

h mAedA

xiv Contents

83 career development process for youth soccer players in

the J-league Academy: career formation and career orientation 471

y iidA, K uemuKAi ANd m y yAmAmoTo

84 youth development structures, philosophy and working

mechanisms of top-level football clubs: a pan-european

h RelVAS, d RichARdSoN, d gilBouRNe, ANd m liTTleWood

3.2 Representative trace of the computational spine to vertical (S2V)

3.3 Representative trace of the computational outside upper leg to

3.4 Representative trace of the computational inside upper leg to

4.1 Rank sums ± ½ Fisher’s LSD for each question asked during

5.1 Athlete motion simulators; ‘manusimulator’ and ‘roboleg’ 31 5.2 Launch characteristics simulators; high speed tennis serve device

5.3 CAD images depicting the completed kicking robot and kicking leg 34 7.1 (a) Definition of marker location and vector for calculation of

3-D foot angular motion; (b) 3-D hemisphere model of the

7.2 Three-dimensional angular displacement of the foot during

7.3 The aspect of ball-foot interaction during ball impact phase 45

9.1 Means and standard errors for ball velocity and GRF

9.3 Means and standard errors for perception parameters 54

10.1 Representation of the stick figure created by linking the

10.2 Knee angular velocity versus time data for each scrum type

10.3 Ankle, knee, and hip angular velocity versus time data for one of the

xvi List of figures

11.2 Contours of velocity magnitude (a) and path lines of the ball (b)

11.4 Flow visualization of a non-spinning soccer ball from side view 67 11.5 Flow visualization of the large-scale fluctuations of the vortex trail 68

12.3 Analysed parameters of the vertical ground reaction force 72

13.3 Comparison of temperature rise on different surfaces 78 13.4 Comparison of sliding distance on different surfaces 78

23.2 Mean (and s.d.) hours per week spent in coach-led practice as

24.1 Relationships between the perceived exertion of players and

24.2 The relative stress indices of the consecutive tournament days

24.3 The relative relaxation indices of the consecutive tournament days 147 25.1 Relationship between the multiple regression model and 15m sprint

27.1 a) Centres of the team during a small-sided game; b) surface area during a small-sided game; c) centres of team when a goal is scored;

31.1 Confidence interval for the average distance run over by the

33.1 An example of the heart rate response of a futsal referee during

33.2 Mean heart rate and peak heart rate for referees in 10-min

List of figures xvii

34.1 The topography of the passes which start actions ended with a

34.2 Accuracy and effectiveness of shots on goal according to the

36.1 High-intensity running in 15 min periods by top-class and

36.2 High-intensity running in 15 min periods by elite female soccer

36.3 Counter-movement jump height (a) and repeated sprint

performance (b) before and after elite female soccer games 209

41.3 Place from what the goal was scored (except for the penalty) 23741.4 Distribution of the periods of play in which goals were scored 238

41.7 The distribution of the players scoring goals according to

42.1 Graphical representation of the treadmill protocol 247 43.1 Core temperature during the soccer-specific protocol with and

44.2 Heart rate during soccer-simulated exercise with cooling (LC) and

44.3 Change in seconds on 30 m sprint during soccer-simulated exercise with cooling (LC) and without cooling (NC) during half time 258 47.1 Periodisation of the various types of training through the different

48.1 Diagram of the rugby-based agility test as viewed from above 280 48.2 Standard residuals for χ2 analysis on overall phase outcome and

50.1 Percent changes in lean leg volume (LLV), maximal half-squat

strength (1RM) and relative half-squat strength (1RM/LLV) 294

51.1 Heart rate during one of the intermittent high-intensity

51.2 Heart rate after 5 min of the Yo-Yo intermittent recovery level 1 test 298 51.3 Performance of the Yo-Yo intermittent recovery level 2 test 299 51.4 Maximum oxygen uptake before and after the IH-period 300 52.1 Two-minute circuit training set to be repeated three times 303 53.1 Mean heart rate (beats.min–1) response to the different speeds

53.2 Rating of perceived exertion for the different speeds and conditions 310 53.3 Post-exercise lactate accumulation due to the different speeds and

xviii List of figures

53.4 Average V.o2 (ml.kg–1.min–1) during the final 2 minutes of exercise 310 54.1 Test score at the PT-test (squares) and CON-test (circles) during

55.1 Percentage of maximal heart rate for two players during an

aerobic high-intensity ‘back-to-back’ exercise drill 325 55.2 Heart rate distribution during two eight-day preparation periods 329 57.1 Activity profile of the 30 min team-sport running simulation 339 59.1 High-intensity running (a) and sprinting (b) of players in top-,

59.2 Yo-Yo intermittent recovery test level 2 performance of

59.3 Individual relationship between performance of the Yo-Yo

intermittent recovery test level 2 and amount of high intensity

running for midfield players during a soccer game 348 60.1 Percentage of total time spent in each heart rate zone for

60.2 Percentage of total time spent in each heart rate zone for Group 2 354 61.1 Individual and mean seasonal changes in the Yo-Yo IR2 test

69.2 A) Salivary cortisol levels of volunteers before (A, AL), soon

after (LD, LLD) and 45 min (45 m, L45 m) after task performance; B) logistic fit to performance of volunteers in a simulated penalty

70.2 Logistic fit of the mean percentage of correct responses as a

function of ‘available time’ in control (PKC) and fatigue (PKF)

70.3 Logistic fit of the mean percentage of correct responses as function

of ‘available time’ in control (PKC) and stress (PKS) conditions 407 71.1 The number of participants identifying positively toned and

negatively toned emotions in their experiences of participating

73.1 Collection of data for players’ sleep duration and perceived levels

of head alertness and leg quickness before a game 421

76.1 Mean group scores for accuracy (%) on perceptual-cognitive tests 436 76.2 Mean memory recall error across groups for individual, team and

77.1 Rate per minute of behaviours exhibited by coaches

77.2 Rate per minute of behaviours exhibited by coaches working

List of figures xix

77.3 Rate per minute of behaviours exhibited by coaches working

84.1 Representation of the two types of club structure evidenced

1.1 Proceedings of the previous Congresses on Science and Football 4 1.2 Distribution of communications to the first five World Congresses on

3.1 Mean angular ranges of motion values of computed lean angles for

4.1 Friedman’s T values for the questions asked during the passing and

6.1 Mean and standard deviation of measured parameters and statistical

8.1 Approach and ball velocities and work performed on the shank

originating from the different movement dependant torques 48 12.1 Analysed parameters for the drop jump on artificial turf with TPE

12.2 The ICC Cronbach alpha value (correlation r) and Wilcoxon signed

13.1 Measured rise in temperature (average and standard deviation) as a

14.2 Lumbar disc degeneration differences between groups 89 14.3 Comparisons of the four groups’ trunk extension/flexion strengths

15.2 Enthesis pain and height growth velocity curve phase 94

List of tables xxi

20.2 Average heart rate, oxygen uptake and energy expenditure

20.3 Proportion of playing time under 50%, between 50–75% and

21.1 Mean and standard deviation of age, weight, height, body fat,

lean body mass and thigh circumference of regional and national

22.1 Year-on-year age data for each measurement approach 135

26.1 Players’ characteristics and physiological responses 156 28.1 Results obtained in the variance and generalizability analysis 168 29.1 The results of teams in the Spanish Football League: the influence

29.2 The results of teams in the Spanish Football League: the influence

of playing the European Champions League for teams making their

30.1 Frequency of activities preceding and following deceleration

30.2 Frequency of movements that preceded and followed

30.3 Frequency of locomotive movements performed immediately

before and after turning movements during purposeful movement within 13 minutes and 45 minutes of soccer match play 178 30.4 Frequency of locomotive movements performed immediately

before and after turning movements of different angles in different

31.1 Distances covered in various positional roles according to types of

32.2 Group tactical actions of teams of different qualification in a game 190 32.3 Number of group combinations in a single scheme of attack and

33.1 Activity profile of futsal referees during competitive games, data are

35.1 Game results of top four games of Asian qualifying Tournament

35.2 Scoring profiles in the Asian qualifying Tournament of 2006

35.3 Mode of play of Asian qualifying Tournament of 2006 WRWC

37.1 Interaction contexts proposed in the observational tool SOCCAF 213 37.1 Matching behaviours for the prospective and retrospective

xxii List of tables

37.3 Obtained adjusted residuals, Pearson’s χ2, degrees of freedom and

38.3 Analysis of variance for individualism and penalty shoot-out

39.1 Whole-game locomotor activity profile of Australian international

39.2 Results of 2006 Women’s Asian Cup, playing formations and

total average distance covered by Australian players per match 226 40.1 Frequency of events performed by players within matches 233

42.1 Mean (°C) ±SD skin (torso) and core temperatures for each

42.2 Maximum and minimum (°C) ±SD skin temperature for each

43.1 Heart rate during the soccer-specific protocol with and without

48.1 Significant correlates between various spatiotemporal stride

variables during the direction changing task, and the linear velocity

49.1 Number of kicks for Group 1 (regulation ARF balls) and Group 2 (combination of regulation and weighted ARF balls) 286 49.2 Mean kick distances and change in distance for Group

regulation balls), Group 2 (weighted balls) and Group 3 (control) before and after a four-week distance kicking intervention 287 50.1 Mean duration of each training item per session during the six

50.2 Changes in force–velocity and power–velocity parameters and peak

52.1 The effect of a six-week strength and practice programme on

55.1 Training schedule for two nine-day periods (phases 1 and 2) before

List of tables xxiii

57.1 Measures of reliability of performance and fatigue variables of

a 5 ×6 s RSA test completed at the end of a 30 min team-sport

62.1 Means and standard deviations for anthropometric variables for age

62.2 Means and standard deviations for HR of the age different groups 362 62.3 Means and standard deviations for running velocities of different

63.1 Percent body fat values (Mean ± SD) and correlation coefficient with

64.1 Means and standard deviations for age, height, and mass of players 371 64.2 Means and standard deviations for independent variables for

65.1 Physiological variables for the treadmill test and FIET protocols 376 66.1 Components of mental toughness in professional soccer 381

71.1 The number, mean intensity and standard deviation of positively toned, negatively toned facilitative, and debilitative emotions

experienced by the participants in the penalty shootout 413 72.1 Stabilographic parameters registered in soccer players 417 72.2 Stabiligraphic parameters registered in soccer players of different

74.1 Descriptive statistics and intercorrelations among study variables 427 74.2 Results of the linear regression analysis for predicting intrinsic sport motivation, extrinsic sport motivation and amotivation 428 75.1 Mean score of Group Embedded-Figures Test (GEFT) 432

78.1 Categories and definitions for time-motion analysis 441

81.2 Mean and standard deviations for game events under different

83.2 Career development process as youth soccer players 473 83.3 Mean and SD for intensity of professional career orientation on

83.4 Mean and SD for intensity of professional career orientation by

The current volume represents the proceedings of the Sixth World Congress of Science and Football The event was held in Antalya, Turkey from 15–20 January

2007, hosted by the School of Physical Education and Sports, Ankara University

in collaboration with the School of Physical Education and Sports at Middle East Technical University The Congress continued the line of previous conferences held under the aegis of the International Steering Group on Science and Football The series of conferences was initiated at Liverpool in 1987, later followed by meetings at Eindhoven (1991), Cardiff (1995), Sydney (1999) and Lisbon (2003) The proceedings providing a scientific record of these events have been published

by E&FN Spon or by the publishers of this volume – Routledge

The Steering Group on Science and Football is one of a number affiliated to the World Commission of Science and Sports This body is charged by the International Council for Sports Science and Physical Education (ICSSPE) with building bridges between theory and practice in specific sports It does so by orchestrating regular conferences and a major World Congress on a four-yearly basis, co-ordinated by the relevant Steering Group and publishing the proceedings This publication therefore is a compendium of research activities and findings which are both up

to date and relevant to practice Its usefulness is reflected in the large number of citations evident in peer-review publications within mainstream journals and the applied nature of the contents

The International Steering Group on Science and Football operates not just

to effect links between research and its applications but also to identify common threads between the various football codes The Congress therefore provides a unique opportunity for cross-fertilization between the football games and the transfer of ideas across them The end result is a strengthening of sport science support work by extending the knowledge base from which personnel working in applied settings can draw

The Sixth World Congress benefited from the administrative help provided by the staff of Serenas Tourism Congress Organisation Services and from its supporting institutions, namely the Turkish Football Federation, the Turkish National Olympic Committee and the General Directorate of Youth and Sport Ernin Ergen and Feza Korkusuz shouldered the bulk of the organisational work, ably supported by their academic colleagues and the Scientific Programme Committee Without the

Preface xxv

support of their many colleagues from within the two universities and the highly efficient secretarial help from Biken Inanc, the Congress administration would have buckled under the enormous workload

The Congress programme included keynote addresses, oral communications, posters, demonstrations, symposia and workshops A special thanks goes to Surhat Münıroğlu for co-ordinating the link with the Turkish Football Federation and for setting up the workshops Technical support at the formal sessions was ably implemented by the staff of Serenas

The presentation of the Book of Abstracts for the Congress was facilitated by

Hakim Gur, editor of the Journal of Sports Science and Medicine These abstracts

were published in a special supplement of the journal (Volume 6 No 10, 2007) These are available at: http://www.fssn.org

An innovation at the closing ceremony of the Congress was the award of prizes

in the open and poster categories prior to the passing of an Australian Rules football

on to the organisers of the Seventh World Congress of Science and Football The literal pass from podium to platform symbolised the inclusion of the different football codes at this gathering as well as the forward progression of the ‘science and football’ movement The location of the next Congress was decided after formal presentations by candidates for host The outcome was that Nagoya, Japan was selected as the site of the Seventh World Congress in 2011 The intervening years are likely to witness further burgeoning in research programmes to reach fruition for communication at this attractive forum for scientific exchanges

Thomas ReillyChair, International Steering Group on Science and Football; President of the World Commission of Science and Sports

(a service group of the International Council for Sports Science and Physical Education)

July 2007

This volume comprises the proceedings of the Sixth World Congress on Science and Football held in Antalya, Turkey in January 2007 It reflects the sustained research output in the different sciences applied to football in its various codes since the first of the series was published in 1988 A comparison of the content

of the six volumes demonstrates how research programmes have paralleled developments within the games All the football codes, international and national forms of football, are represented and the range of topics addressed testify to the fact that football is a fertile area for research investigation

The contents represent a record of the subjects covered in the Sixth World Congress for those manuscripts having passed the peer review process The ten parts of the book demonstrate similarities with previous volumes and illustrate

a balance of work across these areas Inevitably there is some overlap between different parts, for example injuries in young football players could find a place either in ‘sports medicine’ or ‘paediatric exercise science’ Similarly, some of the contributions in the ‘social sciences’ section might have been included with

‘paediatric exercise science’ The decision was based on attempts to provide a reasonable balance in the distribution of articles among the parts of the book.Roughly one-quarter of the communications at the Congress were accepted for publication The editors thank the authors for their careful preparation of manuscripts and also the referees for scrutinising the first drafts A special note

of thanks for coping with the nuances of the electronic submissions and revisions goes to Laura Ramsay and zoe Miveld at the office of the Research Institute for Sport and Exercise Sciences at Liverpool John Moores University Whilst the contents constitute but a fraction of the material presented and discussed at the Congress, they nevertheless provide a sizeable sample of activity at the event They also identify for readers the areas of research into football that are currently attracting scientific investigation

Thomas ReillyFeza Korkusuz

Part I

Introductory keynote address

1 Science and football

This opening address provides an opportunity to place the Sixth World Congress

in Science and Football in perspective The event is held every four years, previous meeting having been organised in Liverpool (1987), Eindhoven (1991), Cardiff (1995), Sydney (1999) and Lisbon (2003) The meetings are held under the auspices of the World Commission of Science and Sports (WCSS) The WCSS has separate steering groups for football, swimming, skiing, racket sports and cricket, with a group dedicated to Science and Cycling recently formed

The aims of the movement in science and football are to:

bring together scientists whose work is directly related to football and

1

practitioners keen to obtain current information about its scientific aspects;bridge the gap between research and practice so that scientific knowledge

2

about football can be communicated and applied;

debate the common threads among the football codes, both in research and

The material communicated at the Science and Football congress is published

as proceedings and contributes to the scientific knowledge base All manuscripts are subject to peer review so there is strict quality control over what findings are reported in the public domain Details of previous proceedings are listed in Table 1.1 and material from these sources is often cited in experimental reports

A glance at previous contents illustrates the range of topics covered (Table 1.2) The most popular area of application is match analysis, irrespective of the code All scientific disciplines are represented and frequently novel use of contemporary technologies are reported and discussed

4 Reilly

The Steering Group is also pivotal in supporting satellite meetings and facilitating links with relevant governing and professional bodies For example, its workshop on ‘talent identification and development’ in Sydney (1999) was a

platform for a special issue devoted to this topic in the Journal of Sports Sciences

(see Williams and Reilly, 2000) The WCSS is formally linked to this journal which was recently the outlet for the FIFA/FMARC Consensus on Sports Nutrition, also published in book form (Maughan, 2007)

Development of science and football

The First World Congress of Science and Football was held in Liverpool in 1987

It was remarkable for a number of reasons, mainly for being the event at which representatives from all the football codes convened formally for the first time Since then there have been noteworthy developments among each of the football games

The increasing commercialisation of association football (soccer) has been linked to its massive television appeal American football arguably has a global audience but without a worldwide attraction Rugby union and rugby league have both professional high-performance levels, accentuated since the first Rugby World Cup was held in 1987 Practitioners in Australian Rules have embraced technology as much as have counterparts in any other game Gaelic football provides a model for community engagement with its firm base in the local parish and inter-county systems The hybrid game of International Rules played between

Table 1.1 Proceedings of the previous Congresses on Science and Football; the first three

volumes were published by E& FN Spon, the last two by Routledge, London

T Reilly, A Lees, K Davids and

W J Murphy

T Reilly, J Clarys and A Stibbe

T Reilly, J Bangsbo and M Hughes

W Spinks, T Reilly and A Murphy

T Reilly, J Cabri and D Araujow

Table 1.2 Distribution of communications (excluding keynotes and workshops) to the first

five World Congresses on Science and Football

Paediatric exercise science

Nutrition and metabolism

Physiology of match-play

Sociology

51 41 39 30 29 27 26 20 16 13 4

Science and football: an update 5

Australia and Ireland is still striving to bring the two codes together satisfactorily

in an international context

There is now opportunity to study football from a range of scientific perspectives Biomechanics and physiology are utilised to examine equipment, shoes and clothing, the immediate interface with players and the training and competitive environment, surfaces, facilities and climate; behavioural, social, economic and organisational issues are relevant topics in psychology and the social sciences The football scenario is constantly changing, this state of flux posing new challenges with each change

In all football codes there has been a growing acceptance of sports science support services Support for coaches and practitioners is primarily in the form

of expertise in performance analysis, nutrition, psychology, lifestyle counselling, physiology and strength and conditioning

The emphasis on performance analysis is reflected in the adoption of camera systems for analysis of activities in matches These services are available

multi-to all the multi-top European association football clubs, individual professional clubs and international rugby teams This service has revolutionised the nature of the feedback given to players and coaches This type of technology has been embraced less readily in assisting match officials, its main input being in the rugby codes.Laboratory methods are still accessible to footballers, mainly when there is a link

to university facilities Assessments include maximal and submaximal responses

in the case of maximal oxygen uptake and determination of lactate threshold, respectively Sophisticated assessment of body composition may be undertaken

using dual-energy x-ray absorptiometry (Egan et al., 2006) Innovations in training

technology are quickly trialled by football players, often before they are validated scientifically These include strength training modalities for improving eccentric muscle actions Deep-water running is more readily accepted in the scientific

literature (Reilly et al., 2003) as useful in recovery, during rehabilitation and as

supplementary training to reduce injury risk Vibration loading that causes damage

in occupational contexts is employed in football contexts without strict guidelines for separating the training stimulus from risk to health

In all the football codes there has been a growing acceptance of sports science support services Support for coaches and practitioners is desired in the form of performance analysis, nutrition, physiology, strength and conditioning, psychology and life-style counselling

Simulating different environments

The work rate associated with match play can be simulated in laboratory conditions using protocols that correspond closely to the activity patterns of competition In this way training and nutritional interventions can be accommodated When a non-motorised treadmill is used, the sprint portion of the protocol can be adopted

as a measure of performance with power output being recorded from measurements

of treadmill belt velocity and the force resisting forward motion

6 Reilly

Hypoxic normobaric chambers have rendered it possible to study altitude and provided an augmented training stimulus, especially during rehabilitation from injury Heat chambers allow players to cope better with high ambient temperatures but pre-cooling the body has been explored as an alternative coping strategy The mechanisms whereby pre-cooling the body assists performance in sports like football have been addressed but post-exercise cooling as a means of assisting recovery processes is still to be fully investigated

The competitive environment is now a worldwide platform for participants in all the football codes The Irish diaspora means that players can compete as far away as Australia and USA There is a brawn drain of rugby union players from Argentina and soccer players from Brazil, mainly to the lucrative professional leagues in Europe Similarly, Europe has benefited from the migration of rugby union players from South Africa and rugby union, rugby league players, coaches and sports scientists from Australia and New zealand Such movement entails travel fatigue, jet lag and climatic stress whose long-term consequences for health are unknown Monitoring such effects places an emphasis on the application of scientific methods and the use

of portable equipment suitable for field conditions (Reilly et al., 2001).

Virtual reality environments provide simulations where the competitive context can be visualised and experienced subjectively In this scenario it is possible to explore individual responses to a range of challenging stimuli The utility of these facilities is yet to be examined in full, albeit useful in defined contexts such as penalty taking Here the eye movements, reactions and forces can be registered to identify characteristics of successful performers

The behavioural and social context

As a social phenomenon, the games are regulated by match officials with varying degrees of power and discretion Referees and their assistants are treated with relative disrespect despite the fact that they are working physiologically as hard as the players This level of strain is reflected in their mean heart rate

The stress on referees is also manifest in the decision-making requirements of the game The quality of mental performance is affected by physiological state and the concomitant exercise at high intensity For example, cognitive performance is likely to be adversely affected at the work-rate levels observed in match officiating (Reilly and Smith, 1986; Reilly and Gregson, 2006)

Football in its different forms is also a great means of bringing communities together Passion is expressed on the terraces and the stands Fan behaviour is still a problem issue, whether it is friendly invasion of the pitch after an important victory or hooliganism at football stadia in Argentina Although largely eliminated from its birthplace in the English leagues, crowd behaviour and control are persistent concerns for the game’s regulators

Science and football: an update 7

The political context

The political context of high-performance sport has changed enormously over the last two decades, since science and football became a recognised entity The Berlin Wall entered was a symbol of separation between Eastern Europe and the western world Eastern Europe, and East Germany in particular, provided the model

of state-aided sports science support This model was in sharp contrast to the funding of the United States Olympic Centre in Colorado Springs, for example The Australian Institute of Sport in Canberra provided a more recent and more polished model, before its expansion to accommodate satellites in the Australian states with a central co-ordinating hub Within Europe the Swedish Olympic Centre receives good reviews from its athletes The Japan Institute of Sports Science (JISS) is technologically the most advanced, with laboratory facilities that are comprehensive and state of the art Other ambitious programmes include the ASPIRE Centre in Doha, qatar, focusing first on soccer, and track and field athletics, its aspirations in the former being realised in its victory in the 2006 Asian Games final

Where the football codes are concerned, there has been a re-think about how best

to identify and develop young talent In soccer France has based its central system

at Clairefontaine The professional clubs in the Netherlands choose to have their own nurseries, a system adopted also in Spain, Portugal and Italy, for example The Football Association in England has moved from a National Centre of Excellence

to locate young talent among the professional clubs What model fits best may depend on national and cultural circumstances Around the world there is huge investment in talent development programmes Thailand is due to follow the JISS model, albeit on a much smaller scale In countries where soccer is not the top sport,

a different model applies The Irish Institute of Sport set up in 2006 caters chiefly for Olympic aspirants, yet Gaelic football, the other Gaelic games and rugby union dominate the competitive sports environment The former games are based on the parish and county units whilst the provinces provide the key to success in rugby union Basketball in Lithuania is the dominant sport so the new football academies

in Kaunas and elsewhere have the task of changing attitudes of youngsters towards the game With organisation and strategy being required for success at international level, those countries without systematic support are at a competitive disadvantage This necessary support includes the input of well trained sports science personnel

Overview

The acceptance of scientific applications to the football codes is no longer questioned Scientific support systems have been promulgated hand in hand with the progressive professionalisation of the various codes of the game at their highest competitive level These developments have been accompanied by the growth of sports science as a viable profession, most notably in its applied aspects

The globalisation of the football games has helped to elevate the level of play

in the domestic leagues that are most highly commercialised The outcome is

8 Reilly

that the cosmopolitan nature of playing populations has made it more difficult

to nurture the national teams in those countries, and in the nations whose best players migrate to participate in the really top leagues The trend has, in turn, placed emphasis on the importance of national schemes for talent identification and development and the incorporation of scientific know-how alongside the craft knowledge of practitioners engaged in such schemes

Participation in high-performance sport is the prerogative of a relatively small proportion of the active population The football codes possess great spectator appeal, generate passion and emotions that sometimes spill over into problems

of misbehaviour and crowd control Their main attraction may lie in football as

a healthy recreational activity and in an era of increasing morbidities associated with a sedentary lifestyle, as a health intervention Arguably, compliance may be better for recreational football than for traditionally prescribed exercise regimens The ultimate benefit of football in its various forms may lie in its ability to promote community commitment in its activities and their outcomes

Nutrition London: Routledge.

Reilly, T and Gregson, W., 2006, Special populations: the referee and assistant referees

Journal of Sports Sciences, 24, 795–80.

Reilly, T and Smith, D., 1986, Effect of work intensity on a psychomotor task during

International Journal of Sports Medicine, 22, 166–74.

Reilly, T., Dowzer, C.N and Cable, N.T., 2003, The physiology of deep-water running

Journal of Sports Sciences, 21, 959–72.

Reilly, T., Cabri, J and Araujo, D., 2005, Science and Football V (London: Routledge) Spinks, W., Reilly, T and Murphy, A., 2002, Science and Football IV (London: Routledge) Williams, A.M and Reilly, T., 2000, Talent identification and development in soccer Journal

of Sports Sciences, 18, 657–67

Part II

Biomechanics

2 The biomechanics of football

a stationary ball that has received most attention in the biomechanical literature The soccer kick is three-dimensional (3D) in nature but it is only recently that 3D studies have been undertaken Prior to that, the studies conducted used a two-dimensional (2D) analysis Naturally, the information derived from these studies was limited, but nevertheless provided a good starting point for future investigations Both 2D and 3D studies have concerned themselves with the kinematics and kinetics of the kicking skill Most have been concerned with the characteristics of the kicking leg although more recently there has been an interest

in the support leg and upper body actions

Other football skills have received less attention The soccer throw-in is one skill which has been the subject of contemporary interest as it is now recognised that a throw-in in the attacking third of the pitch can provide goal-scoring opportunities

The purpose of this overview is to report recent developments in the application

of biomechanics to selected football skills

analyses of the kicking skill: 2D and early 3D studies

Lees and Nolan (1998) have previously reviewed a number of 2D studies This review has been useful for (a) defining the general characteristics of the kicking skill as it evolves from the young child to the mature adult; (b) providing values of maximal ball velocity (ranging between 20 to 30 m.s–1); (c) establishing the nature

of football interaction (ball velocity is approximately 1.2 times foot velocity); (d) reporting data on kicking leg linear kinematics (velocities of the ankle, knee and hip); (e) describing kicking leg angular kinematics (segmental interaction between the thigh which rotates more slowly and the shank which rotates more rapidly during the downswing); (f) reporting kicking leg angular kinetics (joint moments at the ankle, knee and hip), and (g) noting ground reaction forces acting

of the skill and most authors had neither the equipment nor analytical skills to

go beyond their 2D approach The frame-rate limitation of 2D analysis was the easiest to overcome, and the availability of more sophisticated high-speed cameras (with frame rates up to and beyond 200 Hz) enabled appropriate recordings to be obtained These cameras were expensive items of equipment and the development

of video provided a cheaper alternative The immediate disadvantage of video was its low frame rate (50 or 60 Hz) which is generally unsuitable for fast skills like kicking High-speed video systems have been developed but these were as expensive as the high-speed cine film cameras and so provided little advantage.The method for obtaining 3D reconstructions of a skill was developed by Adbel-Aziz and Karara (1971) but it was only in the early 1990s that this method began

to have an impact on sports skills This was due to the cost of multiple cameras and the development of suitable algorithms for implementing the method The method required two or more 2D recordings from cine film (or video) and from the coordinates recorded from each view it was possible to reconstruct the 3D position of the joint marker This was a time-consuming process which required the manual digitisation of many points in each frame of film over many frames and for a minimum of two camera views Nevertheless, biomechanists were interested

in applying these new analysis methods to sports skills in general, and the maximal instep kick in particular Many reports using this method were incomplete and most have, in general, not managed to identify critical characteristics of the 3D nature of the kicking action, namely hip, trunk and shoulder rotations Further comment on these limitations is provided by Lees and Nolan (2002)

Contemporary 3D studies of kicking

The increasing availability of suitable equipment for analysing 3D sports skills meant that by the end of the 1990s more detailed analyses were being reported

in the literature These studies in general are characterised by appropriate methodology, detailed presentation of data, including a focus on the 3D aspects of the skill and a sound discussion of results

Kinematic analyses were the first to be reported in the literature A kinematic description and a comparison of the kicking leg for the maximal instep and side-foot kicks have been reported by Levanon and Depena (1998) for skilled amateur players They used a dual film camera configuration and a frame rate of 200 Hz

As well as reporting a comprehensive set of data for joint angles of the ankle, knee and hip in three planes (flexion/extension, abduction/adduction, internal/external rotation) for each kick, they also presented the only data in the literature to date

The biomechanics of football skills 13

on the orientation of the pelvis during the kick Unsurprisingly, the authors found that the side-foot kick was slower with the foot and shank angled out more (to give

a side foot impact with the ball) The value of this study, however, is that it reports comprehensive 3D data for kicking leg kinematics which had been rigorously obtained It should therefore be considered as a landmark report in this area

Nunome et al (2002) also had an interest in the instep and side foot kicks but

they also reported the kinetic characteristics of the joints of the kicking leg for skilled amateur players The kinetic analysis of kicking has been surprisingly absent from the literature since the early 2D work reported in Lees and Nolan (1998) In Nunome and co-workers’ study, the authors also used a dual film camera system operating at 200 Hz and reported data on joint moments at the ankle (about 35 Nm dorsiflexion, 15 Nm inversion) knee (about 100 Nm extension, 15 Nm external rotation) and hip (about 280 Nm extension, 40 Nm external rotation, 100 Nm adduction) Small differences were apparent between the instep kick and the side foot kick which related to the slower and more outwardly rotated foot in the side foot kick The value of this study is that it was the first to provide comprehensive and rigorous 3D kinetic data on kicking

Changes in the variables that characterise the kick as the speed of the kick increased were investigated in professional players by Lees and Nolan (2002) Ball speed was manipulated by using a speed–accuracy paradigm so as the accuracy demand increased the speed of kick reduced This was thought to be a more appropriate manipulation of kicking speed than by asking subjects to make voluntary changes They used a dual film camera system operating at 100 Hz and concluded that (1) the movement patterns demonstrated by players were consistent, but greater consistency was associated with the slower more precise action used in the accuracy condition and (2) the increases in ball speed were associated with increases in range of motion at the pelvis, hip and knee joints The latter finding was related to a ‘principle of movement’ which implies that to increase performance, a greater range of motion at the joints is necessary

Nunome et al (2006) extended their previous research to investigate kinematic

and kinetic characteristics of kicking with the preferred and non-preferred foot, again using a dual film camera system at 200 Hz and skilled amateur players They found ball velocities of 32 and 27 m.s–1 with foot velocities of 22 and 20 m.s–1 for the preferred and non-preferred foot respectively The difference in performance was attributed to the greater speed of the preferred foot, which in turn was related

to the increased muscle moment at the knee They concluded that the improved performance of the preferred foot was due to strength rather than co-ordination

in their highly skilled players Of course, the same may not be true for less skilled players

All of the above studies focused exclusively on the kicking leg during a maximal

kick Kellis et al (2004) investigated the influence of approach angle on the 3D

kinematics of the support leg for skilled amateur players They used a dual video camera system operating at 120 Hz They also investigated ground reaction forces and the influence of approach angle They reported that approach angle had no effect on ball speed, contrary to that reported by Isokawa and Lees (1988) They