Sport and the cycle

Interesting facts about the mutual influence of sport and the menstrual cycle

As a recreational or professional athlete, you have probably noticed that you perform better in some phases of your cycle. We'll explain why in the following.

One important insight right from the start: women can train more effectively if they pay attention to their cycle! A workout in the first half of the cycle is much more effective than in the second half, according to studies conducted by the Universities of Bochum and Umeå (Sweden)^1,2. The scientists found that maximum strength and muscle thickness increased significantly better in the follicular phase (time before ovulation) than in the luteal phase (time after ovulation).

The Swedish researchers divided the women between the ages of 18 and 35 into three groups. One group of women exercised three times a week regardless of their cycle. The second group did this five times a week only in the first phase of their cycle. The third group also exercised five times, but only in the second half of their cycle. The results were clear: the women who exercised in the first phase of their cycle gained significant muscle mass, while the other two groups did not.

Why training in the first half of the cycle is more effective

The reason for the different training effects is the changing hormone concentrations during the cycle (see figure). In the first half of the cycle, the hormone oestradiol increases until ovulation, which acts like the body's own doping. With ovulation in the middle of the cycle, the concentration of oestradiol decreases, but the level of progesterone increases. Progesterone does not have an anabolic (building up) effect, but on the contrary, a rather catabolic (breaking down) effect. This explains why your training is more efficient in the first half of the cycle than in the second.

Exercise during menstruation

Even if some people prefer not to exercise during their period, sport is actually beneficial. Physical activity reduces muscle cramps as well as pain³ - and bad moods don't stand a chance!

How too much exercise can reduce your fertility.

If you want to get pregnant, you should not exercise too intensively. Exercising every day to the point of exhaustion has a negative effect on fertility. This was found by researchers at the University of Science and Technology in Trondheim, Norway⁴. If you have a desire to have children and want to exercise every day, you should do so only moderately. It is even better to take a few recovery days a week.

However, not exercising at all would be the wrong approach, because it would also reduce your chances of getting pregnant. The scientists advise sports fanatics to watch out for warning signs such as long cycles or the absence of menstruation. However, they can also give the all-clear: In the long term, extreme sport has no effect. The important finding of the studies is that if you cut back on your exercise, your chances of getting pregnant increase.

How to get to know your body and cycle better with Daysy.

Many women are not fully aware of the changes in their body that are directly related to their cycle. Our fertility tracker Daysy helps you know when you are ovulating and what phase of your cycle you are in. This will help you coordinate your training and exercise in harmony with your body's own rhythm.

Live in harmony with your body and get to know yourself and your cycle better!

¹⁾ Sung, E. et al. Effects of follicular versus luteal phase-based strength training in young women. (2014). doi:10.1186/2193-1801-3-668

²⁾ Frisén, L. W. Mood and Oxytocin Blood Levels in Physically Active Women with and without Oral Contraceptive Use in Relation to Seasonal Daylight Variation. Int. J. Sport. Exerc. Med. 3, (2017).

³⁾ Dehnavi, Z. M., Jafarnejad, F. & Kamali, Z. The Effect of aerobic exercise on primary dysmenorrhea: A clinical trial study. J. Educ. Health Promot. 7, 3 (2018).

⁴⁾ Hakimi, O. & Cameron, L.-C. Effect of Exercise on Ovulation: A Systematic Review. Sport. Med. 47, 1555-1567 (2017).

Authors: Niels van de Roemer, Andrea de Groot, Petra Schenke