Jessica James

Females are often excluded from exercise performance research due to experimental challenges in controlling for the menstrual cycle (MC), causing uncertainty regarding how the MC impacts female performance. The present study examined the influences that biological sex and the MC have on the power-duration relationship (PDR) by comparing critical power (CP), Work-prime ( W′), and maximum power output ( P MAX ) in males and females. Our data provide evidence that the MC does not influence the PDR and that females exhibit similar reproducibility as males. Thus, when conducting aerobic endurance exercise research on eumenorrheic females without menstrual dysfunction, the phase of the MC does not need to be controlled. Although differences in body composition account for some differences between the sexes, sex differences in W′ and P MAX persisted even after normalizing for different metrics of body composition. These data highlight the necessity and feasibility of examining sex differences in performance, as previously generated male-only data within the literature may not apply to female subjects.