Menstrual Cycle and Performance: What Is Next?

United Nations data indicate that the world includes approximately 2 billion women of reproductive age. ⁶ General growth of this population segment and the increased participation in sports by women worldwide has generated scientific interest in the potential impact of menstrual cycle (MC) fluctuations on sport and exercise performance.

Early beliefs that exercise during menstruation could lead to infertility were rebutted by American physician Mary Putnam-Jacobi’s seminal research related to the effects of menstruation on physical performance. This work resulted in her being awarded the Boylston Prize in 1876 by Harvard University. ⁵ Subsequent research has proposed various physiological explanations of MC-based changes in performance. ³ Conventional wisdom and related sociocultural beliefs that MC phase is linked to physical performance do not have clear scientific support. The current literature related to this topic is inconsistent, with some evidence suggesting MC fluctuations may affect resistance training parameters and other research indicating only trivial impacts on physical performance. A recent umbrella review ⁴ synthesized 5 other reviews on this topic and concluded that there was no evidence to support the claim that performance is affected by the MC and pointed to the lack of robust study designs as a primary limitation of the current body of knowledge.

Well-established thus far is that ovulation is characterized by a surge in luteinizing hormone and this action triggers follicular rupture. As such, prevailing beliefs suggest that ovulation consistently occurs midcycle and divides the MC into 2 equal-length phases, but this now seems to be an overgeneralization given observed MC variability. ² Adoption of accurate and reliable MC phase detection methods is now recognized as a primary challenge and objective of contemporary MC research, which must address the patterns and timing of sex-related hormones in order to advance this important field of study.

Emerging insights also suggest that future research must consider individual variations within and across individuals. ¹ Anecdotal reports indicate that MC symptomatology is often modest and manageable, but may sometimes be severe and unbearable. Wide symptom variation presents challenges in the development of appropriate exercise programming. These observations generate important questions. Can we confidently state that all women are significantly impacted by MCs? Can we draw conclusions about the impact of the MC based on a single cycle? To answer these questions research must consider variations and reevaluate performance on a woman-to-woman, cycle-to-cycle, phase-to-phase, and day-to-day basis, all of which require adopting novel and rigorous methodological criteria.