Women in Motion. Exploring the Dynamic Relationship of the Menstrual Cycle with Physical Activity and Exercise

The menstrual cycle (MC), a monthly series of changes the body goes through to prepare for a possible pregnancy, is crucial to females' reproductive lives. Despite its significance in female life, a substantial 80% of females encounter MC-related challenges at some point in their reproductive age. MC-related symptoms and disorders have the potential to impact women's overall health negatively. Concurrently, physical activity (PA) and exercise is recognized for its positive influence on well-being and health. While suggestions exist regarding the reciprocal relationship between PA and the MC, inadequate research exists on this interplay, particularly in recreationally active females. This dissertation addresses this gap by investigating the association between PA, exercise and MC-related symptoms and disorders in recreationally active females through a cross-sectional survey. Additionally, it explores the effects of MC-adapted endurance training on performance, cardiovascular health, and premenstrual syndrome through two randomized-controlled trials. The cross-sectional study highlights elevated prevalences of premenstrual syndrome, oligomenorrhea, and secondary amenorrhea among recreationally active females, underscoring the critical need for menstrual health considerations in this population. Although marginal associations were observed between light/moderate PA, total training volume, and MC disorders, no significant relationship was found concerning PA and premenstrual syndrome. Furthermore, the training interventions of the randomized-controlled trials significantly improved aerobic capacity in naturally menstruating females, yet no additional benefits were observed for MC phase-adapted training in terms of performance, cardiovascular health, or premenstrual symptoms. The results suggest that periodized training adapted to the MC may not yield distinct advantages over traditional training in this population. However, the substantial individual variability in training responses in all intervention groups must be emphasized. The observed variability underscores the necessity for replications with extended intervention periods, larger sample sizes, and improved accuracy in MC determination, guiding the refinement of training strategies for females. Future research should explore diverse populations, considering those at risk for MC-related health issues or with comorbidities, and analyze various outcomes, including MC health, well-being, and enjoyment, to enhance our understanding and contribute to long-term PA adherence.