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Abstract Females have often been reported to have a greater muscle fatigue resistance than males, especially during exercise at low-to-moderate intensities. Differences in muscle mass, muscle metabolism and voluntary activation patterns have been the primary explanations for the differences in performance and physiological responses to exercise between sexes. However, while ample data are available for isometric contractions, dynamic activity is a less studied mode of exercise, and there is even less information regarding multiple-sprint exercise (MSE). This is surprising given that MSE places unique demands on metabolic processes in the muscle where energy supply oscillates between fuelling contractile activity and restoring homeostasis. As such, MSE provides a rich area for future applied research. This review examines the limited data available concerning the physiological responses of males and females to sprint exercise, and discusses the methodological confounds arising from non-appropriate comparison methods. Based on original findings, we highlight that sex differences in the absolute mechanical work performed during a given task might explain a significant part of the differences in physiological responses of males and females to sprint exercise. We therefore suggest that future studies using male and female subjects to answer basic physiological questions use mechanical work as a covariate.
Human skeletal muscle fatigue can be defined as a transient, exercise-induced reduction in the maximal force capacity of the muscle.'1·21 Several mechanisms have been proposed that contribute concurrently to the fatigue exhibited by a muscle or muscle group following exercise, and the classic approach used to identify the cause of muscle fatigue has been to distinguish between 'central' and 'peripheral' mechanisms. Typically, peripheral skeletal muscle fatigue involves processes occurring at or distal to the neuromuscular junction, in the presence of unchanged or increasing central motor output.'3"61 On the other hand, central fatigue is due to failure at a site within the CNS.[27,8] Studies applying an electrical stimulus to peripheral nerves and/or a magnetic stimulus to the motor cortex have demonstrated that both 'central' and 'peripheral' mechanisms are involved during fatiguing contractions, and a number of good scientific reviews on this topic are available to the reader.[1,2]
It has also been demonstrated that human skeletal muscle fatigue is influenced by the biological sex of the individual.'9"1 1I Studies on the physiological function of females have...