The number of women practicing any type of exercise has increased a lot during the last decades, not only as a way of doing physical activity, but also at professional level. Women competing in Seoul 1988 were a 26%, a percentage that increased up to 45% in Rio 2016.
Despite this rise in sports women numbers, research focused on them is still limited. Because of their anatomical, physiological and hormonal differences it should not be assumed that research on men could be applied to them, and it happens too often.
The menstrual cycle (MC)
The MC is a biological rhythm affecting women characterised by a cyclic fluctuation in hormones, specially oestrogen and progesterone.
It is divided in three phases:
- Early follicular, with LOW oestrogen and LOW progesterone levels.
- Ovulatory, with HIGH oestrogen and LOW progesterone levels.
- Mid-luteal, with HIGH oestrogen and HIGH progesterone levels.
Although the main function of these hormones is related to reproduction, research has found that they also have multiple effects in many physiological systems, including the cardiovascular and respiratory. Consequently, they should influence exercise performance too.
A recent meta-analysis investigated the changes in exercise performance during the MC phases. It included 78 studies (total of 1193 participants, 18-40 years old, healthy, not taking hormonal contraceptives), although only 8% were valued as “high quality” and 24% as “moderate quality”.
We point out its main findings.
Exercise performance across the MC
- During the early follicular phase exercise performance might be slightly reduced when comparing with other phases, although with a big variance between studies.
- The current knowledge does not support a general guidance on modulating exercise across the MC. A personalised approach should be followed, based on the individual response of each women, of special interest in elite sportswomen.
- Future studies with better methodologies regarding factors such as training history or participants characteristics will help for a better understanding of performance across the MC.
Bibliography
The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis. McNulty, K.L., Elliott-Sale, K.J., Dolan, E. et al. Sports Med 50, 1813–1827 (2020). https://doi.org/10.1007/s40279-020-01319-3