Author(s): KUBICA, C., REIFLER, L., LEHMANN, L., NIGG, C.R. , Institution: INSTITUTE OF SPORT SCIENCE , Country: SWITZERLAND, Abstract-ID: 684

INTRODUCTION:
Subjective perceptions suggest that the menstrual cycle (MC) may negatively affect physical activity (PA), particularly in the presence of premenstrual symptoms (Kolic et al., 2021). However, most evidence is based on cross-sectional designs, limiting insight into MC phase-based variability (Goaplan et al., 2024). This study examined daily fluctuations in PA and premenstrual symptoms across two consecutive MCs using a longitudinal design.
METHODS:
Women aged 18–35 years with a natural MC (21–35 days) completed daily assessments over two consecutive MCs via a mobile application. Measures included MC tracking, premenstrual symptoms (Screening Instrument for Premenstrual Symptoms), and self-reported PA. PA was analyzed separately for light (LPA), moderate (MPA), and vigorous (VPA) intensities. MC phases were classified as menstrual (MP), follicular (FP), ovulatory (OP), luteal (LP), and premenstrual (PP) according to Elliott-Sale et al. (2025). Linear mixed-effects models were used to examine phase-related differences, adjusting for symptom burden and relevant covariates.
RESULTS:
Thirty-five women (26.5 ± 5.4 years) contributed 1,456 daily observations across two MCs. MC phase was not associated with LPA, MPA, or VPA. For LPA, no significant phase differences were observed, although a trend toward higher activity during the ovulatory phase emerged (β = +7.67, p = 0.079); women with PMS showed higher overall LPA (β = +20.70, p = 0.033). MPA did not differ across MC phases, but higher symptom burden was associated with lower MPA (β = −0.65, p = 0.035). No MC phase effects were observed for VPA (all p > 0.30).
CONCLUSION:
PA levels were largely stable across MC phases at the group level. Premenstrual symptom burden showed modest but consistent associations with PA, suggesting that symptoms, rather than MC phase per se, may be more relevant for understanding day-to-day PA behavior.
References

Elliott-Sale, K. J., Altini, M., Doyle-Baker, P., Ferrer, E., Flood, T. R., Harris, R., ... & Burden, R. J. (2025). Why we must stop assuming and estimating menstrual cycle phases in laboratory and field-based sport related research. Sports Medicine, 55(6), 1339. https://doi.org/10.1007/s40279-025-02189-3

Gopalan, S. S., Mann, C., & Rhodes, R. E. (2024). Impact of symptoms, experiences, and perceptions of the menstrual cycle on recreational physical activity of cyclically menstruating individuals: A systematic review. Preventive Medicine, 184, 107980. https://doi.org/10.1016/j.ypmed.2024.107980

Kolić, P. V., Sims, D. T., Hicks, K., Thomas, L., & Morse, C. I. (2021). Physical activity and the menstrual cycle: A mixed-methods study of women’s experiences. Women in Sport and Physical Activity Journal, 29(1), 47-58. https://doi.org/10.1123/wspaj.2020-0050