Menstrual cycle and exercise
How the menstrual cycle affects women’s sports performance has been studied for decades. But not only in that of high-performance athletes, but also in those who practice it as an amateur, or simply exercise in the gym.
The hormonal explosion and its variability during the cycle mean that the responses and adaptations to exercise are completely different as the days go by, and even the individual symptoms before and during the period mean that the workouts must have special peculiarities.
The ovaries and endometrium appear to be the main protagonists, but in reality they coordinate in a complex and sequential way with the hypothalamus and the anterior pituitary. The hypothalamus secretes gonadotropin (GnRH), which stimulates the anterior pituitary, which secretes both follicle stimulating hormone (FSH) and luteinizing hormone (LH). GnRHs stimulate the ovary to produce steroid hormones, estrogen, and progesterone, as well as several key peptides (autocrine, paracrine, and endocrine). Steroid hormones in turn stimulate endometrial proliferation.
The menstrual cycle is made up of the follicular phase (days 1 to 14) and the luteal phase (days 14 to 28). During the follicular phase, folliculogenesis occurs , which is the maturation process of the ovarian follicle, and its phases are as follows: promordial follicle, preantral follicle, small antral follicle, preovulatory follicle, and corpus luteum.
Changes during the menstrual cycle that affect training
- Basal temperature increases during the luteal phase.
- The follicle-stimulating and lutenizing hormones remain at moderate levels during the follicular phase, but peak just before and during ovulation, especially FSH. LH levels are higher during the follicular phase than during the luteal phase, and have a small drop just before ovulation occurs. FSH levels are also higher in the follicular phase than in the luteal phase.
- Progesterone levels increase progressively in the luteal phase, to begin to decrease, from day 21, also progressively.
- Estrogens have three peaks during the cycle: the first, very mild, during the first week of the cycle; the second, the highest, from the second week, obtaining the maximum values during ovulation, decreasing progressively, to finally rise moderately until the beginning of the last week.
What happens during the cycle can easily be affected by environmental factors, such as exercise, stress, eating disorders, and obesity. In fact, it has been possible to verify how there is a strong inverse association between physical activity and estrogen levels in the luteal phase.
But how should I schedule training so that these hormonal levels and other issues associated with the menstrual cycle do not interfere too much with the adaptations I want to achieve?
- In the first 5 days (primary follicular phase) the intensity should be mild.
- From day 6 to 8 (middle follicular phase) the intensity must be moderate, it is a conditioning zone.
- From day 9 to 13 (late follicular phase) the intensity should be increased, combining strength and metabolic training.
- Right at ovulation and in the days after (day 15-20, primary luteal phase), although the intensity remains high, the components are directed more towards maximum strength and power.
- From day 21 to 24 (medium luteal phase) the intensity is moderate again and you return to a conditioning zone.
- Before menstruation arrives, in the last days (late luteal phase), the intensity should be reduced again, moving to a regeneration zone.
Inform your coach about your menstrual cycles, adapting the training can help you achieve your goals sooner. In addition, knowing the irregularities in menstruation also tells us why the desired changes occur sooner or later.