Krah, S. A., Gonzales, J. U., Thompson, B. C., Thistelthwaite, J. R., & Scheuermann, B. W. (2006). Fatigue in females and males in response to repeated bouts of 30 s sprint cycling exercise. Medicine and Science in Sports and Exercise, 38(5), Supplement abstract 1729.

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"Studies demonstrate that females exhibit a greater resistance to fatigue than males and that this difference may persist even when differences in maximal force generation are taken into account. Most studies examining sex differences in fatigability have utilized either small or isolated muscle groups with relatively fewer comparisons made during whole body supramaximal exercise. However, studies indicate that ATP recovery between repeated sprint exercises is faster in females than males suggesting that differences in fatigability between the sexes may become more apparent with repeated bouts of supramaximal exercise".

This study compared the effect of repeated bouts of 30-s sprint cycling on peak power, rate of fatigue, and magnitude of muscle fatigue in males (N = 9) and females (N = 14). VO2peak was determined for all Ss. On a separate day, Ss performed three cycling sprint tests, each 30 seconds long with five minutes of rest between each trial. The resistance during the sprint test was set at 0.7 x body weight. Peak power (PPWR), mean power (MPWR) and overall fatigue index (FI = (peak - minimum power)/30 s) was determined for each trial. The rate of muscle fatigue (RMF) was determined by linear regression of power output from 5 to 30 seconds of exercise so as to exclude the rapid initial decline in power output at the onset of exercise.

Both peak and mean power were significantly higher in males than females in all three trials. Peak and mean power decreased progressively in both genders from trial 1 to trial 3 and remained significantly higher for males than females in spite of the correction for differences in body mass. The relative decline in power output (i.e. expressed as % from initial values) was similar between the genders (averaged across trials: males = 69.9%; females = 67.0%). The ratio of iEMG to power output was consistently lower (p<0.05) in males than females across each of the trials.

Implication. Both genders are similarly resistant to sprint cycling fatigue.

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