The menstrual cycle is a key physiological process in women: it impacts performance, neuromuscular control, metabolism, and immune response. For professional female athletes, fluctuations in hormones that happen throughout the menstrual cycle could impact risk of injury.
Now, researchers in Spain and the UK have set out to examine whether menstruation determined injury incidence or severity in professional female football players. They published their results in Frontiers in Sports and Active Living .
"We show that menstruation itself does not increase how often injuries happen," said first author Dr Eva Ferrer, who specializes in sports medicine at Sant Joan de Déu Hospital and is a female health specialist of the Barça Innovation Hub in Barcelona. "Although athletes were not injured more often during their period, the injuries that happened during menstruation caused three times more days lost than injuries occurring at other times of the cycle."
On the bench
Over four seasons, from 2019/20 to 2022/23, the team monitored self-reported menstrual cycle data of 33 elite football players competing at the highest level of league competition (Liga F) for women's football in Spain. 11 players were included in all four seasons. Players logged bleeding and non-bleeding days, the only phases of the menstrual cycle that can be reliably identified without blood hormone testing. A total of 852 menstrual cycles and 80 lower limb injuries, 11 of which occurred during menstrual bleeding phases, were recorded.
The findings showed that injury burden was significantly higher during bleeding phases, which indicates a greater impact of injuries occurring during menstruation. Those injuries were more severe and took longer to heal. For example, the burden of soft tissue injuries – on muscles, tendons, and ligaments – was more than three times as high when injuries were sustained during bleeding days compared to non-bleeding days, with 684 vs 206 days lost per 1,000 training hours, respectively.
Injuries are caused by multiple factors, and hormonal influences alone cannot be understood as the only cause. "Hormonal levels may not cause the injury, but they may influence how severe the injury becomes and how long recovery takes," Ferrer explained. Low estrogen levels may reduce muscle repair and increased fatigue, pain, and sleep can alter neuromuscular control. Similarly, iron loss can lower endurance and slow recovery and inflammation that may be heightened during menstruation can cause worse tissue damage when it occurs.
To prevent injuries during menstruation and reduce their impact on players' health, small things may go a long way. "Small modifications such as longer warm-ups, adjusted high-speed workload, or added recovery support may help reduce the severity of injuries if they occur," Ferrer pointed out.
Stay on the ball
The team said their findings have implications beyond professional football. Women who work out can use them to adapt their training schedules according to the phases of their menstrual cycle. "You do not necessarily need to avoid training during your period, but you may need to adapt it," Ferrer pointed out. "Tracking your cycle and symptoms can help guide training intensity and recovery strategies."
While the athletes who participated in the study followed consistent injury prevention protocols, had access to professional medical support, and trained under standardized methods, the results may not be readily transferable to all female football players, because participants all belonged to the same club. The unequal amount of bleeding and non-bleeding days, four against 27 in a month, could limit the statistical power to detect differences in incidence. In addition, no hormone measurements were carried out, and external factors such as stress, sleep, nutrition, and symptom severity were not measured. Yet, the observed trends, combined with the significant difference in injury burden, underscore the importance of further research, the authors said.
The study also highlights the importance of individual menstrual tracking, at least with a calendar-based method, for injury prevention. It also constitutes an important step towards integrating menstrual cycle awareness into athlete health monitoring. "It supports a growing movement toward female-specific sports science instead of applying male-based research models to women," concluded Ferrer.
