Gender-specific injuries

As always, there are many reasons for this. But one of the most important is that it is significantly more difficult to collect sound research on injuries to female players. There is preliminary evidence that women are injured at different rates during the menstrual cycle.

This means that in a study, researchers need to know exactly at what point in the menstrual cycle the female player was injured. In many studies, the women's menstrual cycle was not included or only roughly estimated. Women's menstrual cycles could not be more different and therefore estimates are extremely inaccurate. And also the menstrual cycle of the same examined woman can vary in each cycle period, which certainly does not simplify the situation. The fact that different contraceptive methods have an influence on the hormonal balance and the menstrual cycle complicates the study many times over.

This is one of the main reasons why for many years research focused primarily on male subjects. For the sake of simplicity, the results were applied to both sexes. In recent years, however, we have seen a change that has also meant that women are now, happily, being studied more specifically.

The most important findings are: The injury frequency of female soccer players per se is similar to that of men's soccer. However, the proportion of serious injuries is demonstrably higher in women's soccer. Female soccer players reportedly have 21% more injury-related absences compared to men, primarily due to severe knee and ankle ligament injuries. Anterior cruciate ligament injuries are 2-8 times more common in female soccer players.

The menstrual cycle is divided into several phases. The first half of the menstrual cycle, the phase between the onset of menstruation and ovulation, is called the follicular phase. The period after ovulation and the beginning of the next menstrual period is called the luteal phase. This cycle is quite automatic and is controlled by certain hormones in the female body, including estradiol. This is a female sex hormone from the estrogen group. It is precisely at the end of the late follicular phase, i.e. at the time with the highest rate of injury, that the concentration of estradiol rises sharply.

Several studies have previously shown that increased estrogen concentration reduces ligament and tendon stiffness. Thus, this finding suggests that the increased estrogen concentration just before ovulation may cause reduced stiffness of tendons and ligaments and that this loss of stiffness increases the risk of injury.

The statistical analysis was explained in a very imprecise and partly contradictory way. Precisely because the statistics are the core of this entire study, the results must be taken with a grain of salt. The players tested were also asked retrospectively on the day of their injury when their last menstrual cycle began. As mentioned above, this is only a rough estimate. In addition, the number of players tested was relatively small and all female soccer players who used contraceptives were excluded from the study. Further studies must now follow in order to be able to confirm and deepen these initial results.

Scientifically, it is still too early to give sound advice on whether training types should be varied over the course of the menstrual cycle. However, it is generally recommended to strengthen muscles, tendons and ligaments through exercise.

A large 2019 review by Pertushek and colleagues in the U.S. showed, for example, that exercises that strengthen leg strength and include jumping and landing exercises have been shown to help prevent ACL injuries. Regular strength training should not be neglected and should include exercises such as Nordic hamstrings, lunges and calf raises, and plyometric training with jumping exercises.

This has been shown to have a positive effect, especially for female soccer players. Exercise programs against cruciate ligament injuries that contain only balance and stretching exercises are less helpful. Incidentally, there are similar results for prevention training against muscle injuries!

In short, young and adult female soccer players need to strengthen their legs! Strength training strengthens muscles, tendons and ligaments and gives the body more confidence to better withstand external forces in borderline situations. And there's no excuse: you can do this form of training in a gym or with your B42 app at any time.

Of course, technological progress also helps research. For example, thanks to modern smartphone apps, we can now ask young and adult female soccer players specifically and anonymously about their individual menstrual cycle over a longer period of time. However, this is not possible without the participation of female subjects, which is why we are very grateful for any participation. The input is done in a short time and the resulting data diversity can provide clearer study results in the future. Stay tuned for more!

Dr. Philipp Baumert (born 1985) studied at the Sport University Cologne (Sport and Performance; Bachelor) and at the University of Frankfurt (Sports Medicine Training/Performance Physiology; Master) and conducted his Master thesis at the Max Delbrück Center for Molecular Medicine in the Helmholtz Association in Berlin.

He then completed his PhD at Liverpool John Moores University (UK) from 2015-2019, researching individual muscular adaptation responses after intense exercise.

Philipp Baumert is now a researcher at the Chair of Sports Biology at the Technical University of Munich, Germany, studying metabolic pathways in muscle growth in collaboration with theTechnical University of Denmark.

Dr. Philipp Baumert, PhD

Technical University of Munich

Faculty of Sport and Health Sciences

Chair of Sports Biology

TUM Campus in the Olympic Park

Connollystraße 32

80809 Munich

Email: philipp.baumert@tum.de

Web: https://www.sg.tum.de/exercisebiology/mitarbeiterinnen/wissenschaftliche-mitarbeiterinnen/