Physiological demands of performance in Classical Ballet and their ...

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Physiological demands of performance in Classical Ballet and their relationships with injury and aesthetic components An original contribution to knowledge By

By Emily A. Twitchett BSc (HONS) GSR, RAD RTS, AISTD A Thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of Philosophy 2009

This work or any part thereof has not previously been presented in any form to the University or to any other body whether for the purposes of assessment, publication or for any other purpose (unless otherwise indicated). Save for any express acknowledgments, references and/or bibliographies cited in the work, I confirm that the intellectual content of the work is the result of my own efforts and of no other person. The right of Emily Twitchett to be identified as author of this work is asserted in accordance with ss.77 and 78 of the Copyright, Designs and Patents Act 1988. At this date copyright is owned by the author. Signature……………………………………….. Date……………………………………………..

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Abstract At performance level, classical ballet is a form of high-intensity, intermittent exercise, requiring a strong aerobic foundation. Existing training methods have remained largely unchanged over the past century, resulting in poorly conditioned dancers who are prone to injury. The purpose of the thesis was to examine, through several inter-related studies, the demands of training and performance at professional level, and whether fitness levels of classical ballet dancers affect both aesthetic components of performance, and injury. All participants were either in the final year of elite vocational training or were professional dancers. Initial, observational, investigations indicated that both rehearsal and performance posed a variety of demands on different ranks of dancer within a company’s structure, and depicted daily workloads which supported previous complaints of fatigue. Before examination of fitness or performance could begin, novel tools to assess both aerobic fitness, and performance proficiency in ballet dancers were designed and tested for reliability and validity. Both tests met with test-retest reliability standards, with 95% limits of agreement of ±6.2 ml.kg.-1min-1 for the aerobic test, and ±1.5 points (out of 10) for the performance rating scale. High overall performance scores were then best predicted by high jumps of both legs and good active flexibility of the left leg (F=4.142, df=3, P=0.042). Following this, an intervention study investigated the effects of a period of supplemental fitness training, designed to enhance aerobic fitness, jump height and local muscular endurance, on the performance scores of a randomly assigned group of dancers. A control group continued with regular training. Performance scores at the outset of the study were compared to those following the intervention period. Overall scores for the intervention group increased by significantly more than those of the control group, (p=0.03), with greatest gains seen for control and skill, indicating that supplemental fitness training, specifically targeting aerobic and local muscular endurance, can help improve performance, particularly elements such as control and skill. Finally, two separate studies confirmed that low aerobic fitness and low body fat percentage were related to injury in ballet dancers. Further research needs to focus on fully ascertaining the physical demands of ballet, and whether better training dancers to meet these demands results in enhanced performance and reduction in injury.

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Table of Contents Abstract ......................................................................................................................................... 2 Table of Contents ........................................................................................................................... 3 List of Figures and Tables ............................................................................................................... 5 Figures ............................................................................................................................................. 5 Tables .............................................................................................................................................. 5 Acknowledgements ....................................................................................................................... 6 1

Introduction.......................................................................................................................... 7 1.1 Reasons for the research ....................................................................................................... 8 1.1.1 Summary of previous research .................................................................................... 8 1.1.2 Research aims ............................................................................................................ 11 1.2

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The research ‘dilemma’; can performance be quantified? .................................................. 12

Literature review ................................................................................................................ 14 2.1 Exercise physiology relating to classical ballet .................................................................... 15 2.1.1 Introduction ............................................................................................................... 15 2.1.2 Flexibility .................................................................................................................... 16 2.1.3 Muscular Strength ...................................................................................................... 21 2.1.4 Muscular power ......................................................................................................... 25 2.1.5 Local Muscular Endurance ......................................................................................... 28 2.1.6 Energy Systems .......................................................................................................... 32 2.1.7 High-intensity, intermittent exercise ......................................................................... 34 2.2 The demands of classical ballet performance and fitness levels of classical ballet dancers 38 2.2.1 Introduction ............................................................................................................... 38 2.2.2 Physiological Demands of Classical Ballet .................................................................. 39 2.2.3 Aerobic Capacity of Classical Ballet Dancers .............................................................. 41 2.2.4 Muscular Power and Endurance ................................................................................ 44 2.2.5 Muscular Strength ...................................................................................................... 45 2.2.6 Anthropometry .......................................................................................................... 48 2.2.7 Flexibility .................................................................................................................... 52 2.2.8 Agility ......................................................................................................................... 53 2.2.9 Summary .................................................................................................................... 54 2.2.10 Recommendations for future research ................................................................. 55

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The demands of classical ballet ........................................................................................... 56 3.1 Video analysis of classical ballet performance .................................................................... 57 3.1.1 Introduction ............................................................................................................... 57 3.1.2 Methods ..................................................................................................................... 58 3.1.3 Results ........................................................................................................................ 59 3.1.4 Discussion ................................................................................................................... 63 3.1.5 Conclusion .................................................................................................................. 67 3.2 The demands of a working day among professional female ballet dancers........................ 68 3.2.1 Introduction ............................................................................................................... 68 3.2.2 Methods ..................................................................................................................... 70 3.2.3 Results ........................................................................................................................ 73 3.2.4 Discussion ................................................................................................................... 76 3.2.5 Conclusion .................................................................................................................. 80

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The development of novel assessment tools ...................................................................... 81 4.1 Development, validity and reliability of a ballet-specific aerobic fitness test ...................... 82 4.1.1 Introduction ............................................................................................................... 82 4.1.2 Method....................................................................................................................... 83 4.1.3 Results ........................................................................................................................ 85 4.1.4 Discussion ................................................................................................................... 88 4.1.5 Practical applications ................................................................................................. 91 4.2 The development, and reliability analysis of a ballet-specific performance test ................. 92 4.2.1 Introduction ............................................................................................................... 92 4.2.2 Methods ..................................................................................................................... 93 4.2.3 Results ........................................................................................................................ 97 4.2.4 Discussion ................................................................................................................. 100

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Associations between fitness, and both classical ballet performance and injury status. ... 104 5.1 Associations between selected fitness parameters and classical ballet performance proficiency ................................................................................................................................... 105 5.1.1 Introduction ............................................................................................................. 105 5.1.2 Method..................................................................................................................... 107 5.1.3 Results ...................................................................................................................... 112 5.1.4 Discussion ................................................................................................................. 116 5.2 Do increases in selected fitness parameters affect classical ballet performance and incidence of injury?...................................................................................................................... 119 5.2.1 Introduction ............................................................................................................. 119 5.2.2 Method..................................................................................................................... 120 5.2.3 Results ...................................................................................................................... 124 5.2.4 Discussion ................................................................................................................. 125 5.2.5 Practical Applications ............................................................................................... 127

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Physical fitness, injury occurrence and time loss through injury ....................................... 128 6.1 Does Physical Fitness Affect Injury Occurrence and Time Loss Due to Injury in Elite Vocational Ballet Students? ........................................................................................................ 129 6.1.1 Introduction ............................................................................................................. 129 6.1.2 Method..................................................................................................................... 131 6.1.3 Results ...................................................................................................................... 132 6.1.4 Discussion ................................................................................................................. 134 6.2 The effect of body composition on injury in elite vocational ballet students..................... 138 6.2.1 Introduction ............................................................................................................. 138 6.2.2 Method..................................................................................................................... 141 6.2.3 Results ...................................................................................................................... 144 6.2.4 Discussion ................................................................................................................. 147

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Summary .......................................................................................................................... 152

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Limitations ........................................................................................................................ 157

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Suggestions for future research ........................................................................................ 159

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Bibliography ..................................................................................................................... 161

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Appendices ....................................................................................................................... 181

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List of Figures and Tables Figures Figure 3-1 The mean time at each intensity, as a percentage of performance ......... 60 Figure 3-2 Occurrence of jumps, plies and changes of direction per minute........... 62 Figure 3-3 Mean work-to-rest percentages ............................................................. 62 Figure 3-4 Percentage of day spent in each intensity band, grouped by ranking ..... 74 Figure 3-5 Mean exercise intensity (METS) ............................................................ 74 Figure 3-6 Amount of rest (minutes) for one minute of work ................................. 75 Figure 4-1 VO2 intake for the final minute of each stage of the test ...................... 86 Figure 4-2 Mean VO2 consumption for the last minute of each stage .................... 87 Figure 4-3 Test- re-test correlation (r=0.998, p