Training according to the menstrual cycle is fashionable. It is enough to do a search on Google or on the main social networks to find multiple applications, videos and articles for women to plan their sports practice based on their menstrual cycle.
"There are millions of views of TikTok videos with advice on training and the menstrual cycle," explained Eva Ferrer, a Sports Medicine specialist at the Clínic and Sant Joan de Déu hospitals, in the session that the Clínic's summer school dedicated to to “Women, physical exercise and sport”. To then ask yourself: “But how does an app, or any of those TikTok gurus who give advice on how to adapt my exercise to the menstrual calendar, know where in my cycle I am? What crystal ball do you have?
Because, explained the specialist, "no calendar tells the hormonal reality of athletes because the menstrual cycle varies from one woman to another and even from one month to another for the same woman because it is affected by various circumstances."
The menstrual cycle changes due to diet, rest, training loads, stress, drugs, if you suffer from any pathology... This means that not even doctors can know at what point in the menstrual cycle a woman is without invasive tests, such as a blood draw, to find out your hormone levels.
“The only moment of the cycle in which we know for sure what phase we are in is when we menstruate; in the rest we can have an idea from the basal temperature in the vagina or from certain symptoms if the woman knows herself a lot and has a very regular cycle; but knowing how the hormones are to determine if at that moment it is better to work on strength or resistance, etc., is only possible with invasive methods, and that is why there are many people in the scientific field looking for other non-invasive markers that allow us to know that reality hormonal”, explains Ferrer to La Vanguardia.
And if neither scientists nor doctors are capable of knowing this information, "it is very difficult for an app or any other digital method to tell us exactly at what point in the menstrual cycle we are or give us valid recommendations to adapt our training plans to that", says the sports medicine expert, also linked to the Barça Innovation Hub (BIHUB).
In her opinion, behind these recommendations and apps that promise to help women improve their sports performance there is much more business than science because the scientific world still knows little and there is little research on the performance or injuries of athletes with real hormonal data. . “There are very few studies of high methodological quality on the subject and many people wanting to monetize the menstrual cycle with athletes”, emphasizes Dr. Ferrer.
She specifies that this does not mean that the menstrual cycle does not affect sports performance or that the recommendations that digital systems can give cannot be useful for women with certain physical exercise goals.
"If you know yourself, you have regular periods and you know when you ovulate and what your cycle is like, you can apply the recommendations adapting them to your case, but knowing what scientific theoretical basis they have," says the expert.
In general, he points out, during the first phase of the menstrual cycle -the period between menstruation and ovulation- estrogen levels increase and therefore it is recommended to do more strength work, while in the second part of the cycle - from ovulation to menstruation- the predominant hormone is progesterone and it is considered more suitable for resistance exercises.
Regarding the relationship between these hormonal peaks and the lesions, Ferrer stresses that the studies carried out to date offer disparate conclusions: “some place the greatest risk of injury in the preovulatory phase and others do not; there is nothing conclusive”.
What they do have proof of, she says, is that exercise and sport generate endorphins and that is why light activity can improve some menstrual symptoms such as heavy legs or abdominal discomfort.
