A groundbreaking study conducted by researchers at University College London (UCL) has revealed that women’s cognitive performance peaks during ovulation, but more strikingly, physical activity levels exert an even more profound influence on brain function than the menstrual cycle phases themselves. Published in the journal Sports Medicine – Open, this research dives deep into the complex interplay between female hormonal cycles and physical fitness, illuminating new pathways to understanding cognitive agility in women and challenging widespread assumptions about menstrual cycle-related performance impairments.
The research team meticulously tracked 54 naturally menstruating women ages 18 to 40, categorized by their athletic involvement ranging from completely inactive to elite national or international competitors. These women underwent rigorous cognitive testing during the four cardinal phases of their menstrual cycle: menstruation onset, late follicular phase (post-menstrual), ovulation, and mid-luteal phase. The design replicated cognitive demands pertinent to both everyday functioning and high-intensity team sports, evaluating reaction time, attention, accuracy, and inhibition control—processes paramount for split-second decision-making and coordination.
Findings disclosed that reaction times were fastest and error rates lowest on the day of ovulation, coinciding with peak fertility when the ovaries release an egg. This phase showed an average cognitive speed advantage of around 30 milliseconds compared to later stages, specifically the mid-luteal phase preceding menstruation, which aligns with elevated progesterone levels. Progesterone’s well-documented sedative effect on the central nervous system presumably underpins the observed slowdown in cognitive processing speed during the mid-luteal phase without compromising accuracy, suggesting a decoupling between speed and cognitive precision within this hormonal milieu.
Despite these cycle-dependent fluctuations, physical activity emerged as a substantially more potent factor influencing cognitive metrics. Inactive participants exhibited reaction times approximately 70 milliseconds slower and committed nearly three times the number of impulsive errors compared to their active counterparts, regardless of where they were in their cycle. This finding underscores the critical role of consistent physical exercise in sharpening the brain’s executive functions, an impact that eclipses the subtle hormonal variations that accompany menstrual phases.
Given that elite athletes sometimes suffer injuries like concussions within narrow temporal windows of their menstrual cycles, this research offers a plausible mechanistic explanation. The marginally faster reaction times during ovulation could confer a protective advantage by enabling more rapid responses to avoid collisions, whereas the slower processing phases may elevate injury risk. However, in everyday life contexts, the 20-millisecond variation associated with menstrual phases is unlikely to produce meaningful changes in performance or safety, whereas the 70-millisecond lag tied to inactivity holds significant practical risks, such as failing to regain balance after tripping.
Dr. Flaminia Ronca, the study’s lead investigator from UCL’s Institute of Sport, Exercise & Health, emphasized the novelty and implications of directly measuring ovulation’s impact on cognition. Her team’s results affirm ovulation as the cognitive sweet spot in the menstrual cycle but, crucially, demonstrate that engaging in physical exercise produces cognitive benefits of a magnitude nearly triple that of hormonal phase shifts. This insight propels the narrative beyond hormonal determinism, positioning lifestyle factors as critical modulators of female cognitive health.
Beyond the physiological data, participants’ subjective experiences revealed a divergence between perceived and actual performance capacity. Over half believed menstrual symptoms debilitated their cognitive function during menstruation, but the objective data told a different story, highlighting better reaction times than during the mid-luteal phase and no increased error propensity. This dissociation between mood, perceived energy levels, and cognitive performance challenges enduring myths and opens avenues for reshaping female health discourse with evidence-based perspectives.
The study employed innovative cognitive paradigms: one assessed inhibition and attention by requiring participants to discern smiling versus winking faces, responding only to smiles to test inhibitory control and reaction speed. Another evaluated spatial timing anticipation relevant to contact sports, asking participants to predict the collision of two moving objects. These task selections enhance the ecological validity of the findings, as they simulate real-world cognitive demands athletes and everyday individuals face.
Moreover, the research categorizes participants’ activity levels into four distinct groups: inactive, recreationally active, club competitors, and elite athletes. This stratification allowed the identification of graded cognitive benefits correlating with increasing physical engagement intensity and competition level. The ability to parse out these nuanced variations supports the contention that physical fitness yields comprehensive cognitive advantages beyond hormonal cycle effects.
The practical implications of this research resonate widely. Dr. Ronca highlights that integrating brief, moderate exercise sessions, such as brisk walks or cycling for as little as 15 minutes, can notably boost cognitive performance and mood. This easily adoptable intervention empowers women across all fitness levels to enhance mental agility and potentially mitigate risks associated with slower reaction times during less optimal hormonal phases.
These findings arrive at a pivotal moment, reframing female cognitive performance through a lens that balances biological rhythms with behavioral choices. By elucidating that physical activity exerts greater influence than hormonal fluctuations, this study nudges the scientific and athletic communities to reconsider training schedules, injury prevention protocols, and public health advice tailored for women. It also dispels misconceptions that menstrual cycles universally impair cognitive function, fostering a more nuanced appreciation of female physiology.
In conclusion, this comprehensive investigation from UCL challenges long-standing assumptions about the menstrual cycle’s impact on cognition by meticulously documenting subtle hormonal effects and spotlighting physical activity as a dominant modulator of brain function. The research champions an empowering message for women: while biology contributes to cognitive ebbs and flows, voluntary lifestyle choices, particularly maintaining regular exercise habits, possess the power to significantly enhance mental agility, mood, and overall cognitive health.
Subject of Research: People
Article Title: Menstrual cycle and athletic status interact to influence symptoms, mood, and cognition in females
News Publication Date: 9-Oct-2025
Web References: http://dx.doi.org/10.1186/s40798-025-00924-8
References: Flaminia Ronca et al., Sports Medicine – Open, DOI 10.1186/s40798-025-00924-8
Keywords: Menstruation, Sports medicine