The female menstrual cycle

The female menstrual cycle is a natural process in the body that usually lasts around 28 days, but can also vary (24-35). It comprises four main phases: Menstruation, follicular maturation, ovulation and the luteal phase.

Menstruation occurs at the beginning of the cycle (day 1 of bleeding is day 1 of the cycle), followed by the maturation of an egg in a follicle. Ovulation is the time when the egg is released and the luteal phase prepares the body for a possible pregnancy. If fertilization does not occur, the cycle begins again. The menstrual cycle is regulated by hormones such as oestrogen and progesterone.

Swiss Olympic 2020

Phase 1 Follicular phase

The follicular phase is the first phase of the female menstrual cycle. It begins on the first day of menstruation and usually lasts around 14 days, but can vary from woman to woman. Important: Day 1 is described as only the real bleeding, and not the brownish discharge or so-called spotting, which can occur a few days before. During the first phase, small structures called follicles develop in the ovaries, each containing an egg. Under the influence of hormones such as FSH (follicle stimulating hormone), a follicle matures and usually one of the eggs is selected for ovulation. The follicular phase ends with ovulation, when the selected follicle releases the mature egg.

 

Ovulation

Ovulation is the time in the female menstrual cycle when a mature egg is released from a follicle in the ovary . This normally occurs in the middle of the menstrual cycle, about 14 days before the start of the next menstruation. Ovulation is triggered by the rise in luteinizing hormone (LH), which causes the follicle to rupture and allows the egg to be released. The egg can then be absorbed by the fallopian tubes and is ready for fertilization by sperm. Ovulation is a crucial step in the reproductive cycle and a key factor in conception.

Luteal phase

The luteal phase is the phase of the female menstrual cycle that follows ovulation. It normally lasts around 14 days, regardless of the total length of the cycle. During this phase, the empty follicle from which the egg was released transforms into a temporary gland called the corpus luteum. The corpus luteum produces progesterone, a hormone that prepares the lining of the uterus for a possible pregnancy.

If fertilization has not taken place, the corpus luteum recedes, progesterone production decreases and the uterine lining is shed, leading to menstruation. However, if fertilization has taken place, the progesterone supports the implantation of the fertilized egg and helps to maintain the pregnancy until the placenta is sufficiently developed to take over this function.

 

Training

Cycle-controlled training refers to adapting the training plan to a woman’s menstrual cycle. Some research suggests that women respond differently to exercise during certain phases of their cycle and their performance may vary .

Follicular phase

In the first phase, women are often more powerful, especially in terms of strength/muscle building. Studies describe a 40-45% higher strength potential at this time. This is supported by the higher increase in the hormone oestrogen. It is recommended that training is organized so that intensive strength training takes place every two days or eight sessions in the first phase of the cycle. Of course, it is important to remember that the first few days of your period can also bring symptoms and the sessions may need to be adjusted accordingly.

Ovulation

Women are much more sociable in the days around ovulation, as nature can guarantee a possible pregnancy. Preventive training should include components such as stability and coordination, as the ligaments, muscles and tissue are somewhat more unstable and softer than usual at this time.

Luteal phase

In the second phase of the cycle, recovery sessions and moderate exercise are more likely to be tolerated. Strength training should not be the focus of training, but can still be carried out once a week or with a total of two sessions during this time. With the increased progesterone, the body temperature rises by approx. 2°C and metabolic activity increases.

 

Cycle-driven exercise takes into account hormonal changes in the menstrual cycle to optimize exercise and better support a woman’s individual needs and goals. However, it is important to note that the effects of the menstrual cycle on exercise can vary from woman to woman, and there is not (yet) enough consistent scientific evidence to provide clear recommendations for all women. It is advisable to listen to your own body and make training adjustments according to your personal needs, preferably with a specialized professional and all parties involved (trainer, therapist, family).

Swiss Olympic 2023

Nutrition

Cycle-controlled nutrition refers to the adaptation of nutrition to a woman’s menstrual cycle. During the cycle, energy requirements, hormone levels and nutritional needs can change. Some women report different preferences, appetite changes and metabolic variations during the different phases of their cycle.

In the follicular phase, which begins with menstruation, there may be a greater need for iron and protein to support blood loss and muscle recovery.

During the luteal phase, which follows ovulation, an emphasis on a nutrient-rich diet, particularly complex carbohydrates, may be useful to cope with the possible increased energy requirements and emotional changes.

It is important to note that needs vary from woman to woman, and there is limited scientific evidence to support specific recommendations for cycle-managed nutrition. Individual preferences and needs should be considered, and it may be helpful to work with a dietitian or health professional to develop an appropriate dietary strategy.

Do you have any questions on this topic? Do you need more information about your cycle, the associated training and/or do you have any problems? Please contact us info@physio-restart.ch.

Author: Anneke Penny

References:

1.Swiss Olympic. Women and elite sport. https://www.swissolympic.ch/athleten-trainer/frau-spitzensport

Webinar by SART Impact of the menstrual cycle on prevention and rehabilitation. 25.11.2023

2.Kiesner J, Eisenlohr-Moul T, Mendle J. Evolution, the Menstrual Cycle, and Theoretical Overreach. Perspect Psychol Sci. 2020 Jul;15(4):1113-1130. doi: 10.1177/1745691620906440. Epub 2020 Jun 15. PMID: 32539582; PMCID: PMC7334061.

3.Carmichael MA, Thomson RL, Moran LJ, Wycherley TP. The Impact of Menstrual Cycle Phase on Athletes’ Performance: A Narrative Review. Int J Environ Res Public Health. 2021 Feb 9;18(4):1667. doi: 10.3390/ijerph18041667. PMID: 33572406; PMCID: PMC7916245.

4.Rogan MM, Black KE. Dietary energy intake across the menstrual cycle: a narrative review. Nutr Rev. 2023 Jun 9;81(7):869-886. doi: 10.1093/nutrit/nuac094. PMID: 36367830; PMCID: PMC10251302.

5. https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/

6. https://my.clevelandclinic.org/health/articles/10132-menstrual-cycle