A new study seems to upend conventional wisdom — and women’s own perceptions of their abilities — by showing that women have faster and more accurate cognitive performance while they are on their period.
Researchers at University College London and the Institute of Sport, Exercise & Health were looking into why previous studies had shown women athletes were more likely to sustain injuries during the luteal phase of their menstrual cycle, which is the time between ovulation and menstruation.
Although scientists have speculated the reason could be related to the hormonal changes that occur during the menstrual cycle, the link to injuries is still not well understood.
In the new study, published in the journal Neuropsychologia, researchers sought to understand sports-related cognition throughout the menstrual cycle. A total of 241 participants completed a battery of cognitive tests 14 days apart, and competed a mood scale and a symptom questionnaire at two separate times. Period-tracking apps were used to estimate where they were in their menstrual cycles when they completed the tests.
In one of the cognitive tests, participants were shown smiling or winking faces and asked to press the space bar only when they saw a smiling face, measuring inhibition, attention, reaction time and accuracy. In the other, they were asked to identify mirror images in a 3D rotation task to assess spatial cognition. Another task asked them to click when two moving balls collide on screen, measuring spatial timing.
The results showed that despite reporting feeling worse while on their periods, and feeling as though that negatively impacted their performance, participants actually had faster reaction times and fewer errors while menstruating.
“Research suggests that female athletes are more likely to sustain certain types of sports injuries during the luteal phase and the assumption has been that this is due to biomechanical changes as a result of hormonal variation. But I wasn’t convinced that physical changes alone could explain this association,” said Dr. Flaminia Ronca, first author of the study from UCL Division of Surgery and Interventional Science and ISEH.
“Given that progesterone has an inhibitory effect on the cerebral cortex and estrogen stimulates it, making us react slower or faster, we wondered if injuries could be a result of a change in athletes’ timing of movements throughout the cycle,” Ronca said.
While menstruating, participants’ timing was on average 10 milliseconds (12%) more accurate in the moving balls task, and they pressed the space bar at the wrong time 25% less in the inhibition task.
Participants who were in the luteal phase of their menstrual cycle were on average 10–20 milliseconds slower compared to being in any other phase, though they didn’t make more errors in this phase.
The difference in timing, though seemingly small, could mean the difference between getting injured or not.
“This study emerged from listening carefully to female soccer players and their coaches. We created bespoke cognitive tests to try to mimic the demands made upon the brain at the points in the game where they were telling us that injuries and problems of timing occur at certain times of the menstrual cycle,” said Professor Paul Burgess, senior author of the study from UCL’s Institute of Cognitive Neuroscience.
“As a neuroscientist, I am amazed that we don’t already know more about this, and hope that our study will help motivate increasing interest in this vital aspect of sports medicine,” Burgess said.
“What is surprising is that the participant’s performance was better when they were on their period, which challenges what women, and perhaps society more generally, assume about their abilities at this particular time of the month,” Ronca said. “I hope that this will provide the basis for positive conversations between coaches and athletes about perceptions and performance: how we feel doesn’t always reflect how we perform.”
