chapter  4
28 Pages

Body Composition and Gender Differences in Performance

ByPeter R.J. Reaburn, Ben J. Dascombe, and Xanne Janse de Jonge

As more and more women started participating in sports over the past 50 years, they embarked on a “catch-up” race for the world records. World records improved at a

4.1 Introduction .................................................................................................. 121 4.2 Gender and Strength ..................................................................................... 123

4.2.1 Gender Differences in Strength Performance .................................. 123 4.2.2 Factors Influencing Strength Performance ...................................... 123

4.2.2.1 Muscle Characteristics ....................................................... 123 4.2.2.2 Neural Activation ............................................................... 125 4.2.2.3 Hormonal Factors .............................................................. 126 4.2.2.4 Menstrual Cycle ................................................................. 127

4.3 Gender and Anaerobic Performance ............................................................ 127 4.3.1 Gender Differences in Anaerobic Performance ............................... 127 4.3.2 Factors Influencing Anaerobic Performance .................................... 130

4.3.2.1 Muscle Mass ...................................................................... 130 4.3.2.2 Bioenergetics and Energy Metabolism .............................. 131

4.4 Gender and Endurance Performance ............................................................ 133 4.4.1 Gender Differences in Endurance Performance ............................... 133 4.4.2 Factors Influencing Endurance Development ................................... 133

4.4.2.1 VO2max ................................................................................ 134 4.4.2.2 Lactate Threshold .............................................................. 137 4.4.2.3 Economy ............................................................................ 138 4.4.2.4 Muscle Mass ...................................................................... 138 4.4.2.5 Blood Volume .................................................................... 139 4.4.2.6 The Role of Estrogen ......................................................... 139

4.5 Summary and Conclusion ............................................................................. 139 References .............................................................................................................. 139

faster rate for females than for males from the 1950s until the late 1980s.1 However, since the 1990s a stable gap has been observed between male and female elite performances, though it is evident that men typically possess greater levels of strength and power, and have larger anaerobic and aerobic capacities.2,3

The relatively small number of gender-specific research studies makes it difficult to elicit the physiological mechanisms responsible for these performance differences between genders. The responsible mechanisms are probably related to specific gender differences such as body composition,3,4 muscle characteristics, 4-7 and hormonal influences.2,8-10 It seems likely that much of the reluctance to include females as subjects in research studies is related to the need to control for hormonal fluctuations due to the menstrual cycles or oral contraceptives. Over the past 10 years, exercise physiology research on gender differences has increased, but many areas require further clarification.