Do We Actually Perform Worse Around our Periods?
To my surprise and confusion when looking into the research, I found study after study saying that there are no differences in how women objectively perform throughout their menstrual cycle! Memory test scores, for example, did not change when comparing women who were ovulating with women who were in their premenstrual phase [1]. A handful of studies did find patterns, but some of those findings could not be replicated in other studies. Right now, you are probably thinking “What? But I feel so much worse on my period, I must be performing worse?!” - I thought the same. In this article I will put these findings into context, and explain what might be going on here.
To be nuanced - the idea that your cycle doesn’t affect your performance isn’t true for everyone. If you live with endometriosis or another condition that causes intense pain, the conclusions from this article probably do not apply to you in the same way. Pain takes up real cognitive space: it's hard to focus on a task when a part of your attention is permanently occupied by how much something hurts [2]. That's not a subjective distortion or a negativity bias, it's a straightforward resource problem, and it's a completely different mechanism from what this article is about.
The focus of this article is a meta analysis (one large paper summarizing the results of many other studies) that looked at cognitive performance across cycle phases (including 102 studies and ~3900 women). It found no significant overall differences in performance across different phases of the menstrual cycle [3]. Most had strict inclusion criteria, though it's not clear whether conditions like endometriosis were consistently screened out across all of them, so take that as an open question. These studies tested many different aspects of performance including: attention, creativity, executive functioning, intelligence, memory, motor function, spatial, and verbal ability, and measures of speed and accuracy in each case. For example, to test spatial ability, someone is shown a 3D shape and a rotated version of it, and has to say whether the second one is the same shape turned around or a mirror image [1].
What this means is that, among naturally cycling women, the average woman who's ovulating doesn't perform any better than the average woman who's menstruating [3]. I know, this goes against so much of what we feel, and what we've been taught or seen reflected in society. Let's unpack why.
So, whats actually going on?
Performance constantly changes.
Menstruation is not the only thing that can influence how well you perform. Everyone’s performance constantly changes because of things like how they slept the night before, an argument with a friend, having a headache, work stress, being hungry and more. Performance varies naturally. That variation in performance is normal, and doesn't seem to get consistently worse around menstruation.
Feeling worse isn't the same as performing worse.
There is a difference between how we feel and think we perform and how we actually perform. How we think we perform would be “Do you feel like you remembered directions well today?”, and a more objective measure of how we perform would be “how many items did you get correct on a memory or attention test? And how long did it take you to answer?”.
When researchers compared women’s day-to-day reports of how well they were concentrating with their later memories of the same time period, the memories consistently painted a worse pictures than the real-time reports. In other words, looking back, we tend to remember our cycles as having affected us more than it actually seemed to in the moment [3].
How we think we are performing ≠ actual objective performance. That doesn't mean that the difficulty is imagined or fake. Feeling worse is very real, and matters on its own, even when it doesn't show up as a lower score.
This idea also shows up clearly in athletic performance. Many athletes really do experience lethargy, pain, or distraction around their period, all of which are real physiological experiences, not something to second-guess. Most athletes report that this affects their performance in training and competition. When researchers reviewed 35 studies on the topic, the picture turned out to be genuinely mixed, 15 found that at least one performance measure was affected by cycle phase, while 20 found no measurable change at all [4]. Interestingly, even in the studies that did find an objective change, it didn't always line up with what the athletes themselves noticed had shifted, which suggests the relationship between how a phase feels and how it affects performance is more complicated than a simple one-to-one link, not that either side is getting it wrong.
Averages hide the real picture.
Averages can hide a lot. If one woman's “dip” happens right before her period, another's during her period, and a third barely notices anything at all, averaging all of them together can look like 'no change,' even though each woman's own experience is completely real. Interestingly, the researchers behind the largest study on this topic raise this same possibility themselves, and note that the differences between individual women could be bigger than any overall cycle effect they were able to measure.
So what should we actually do?
If population averages cant capture your own pattern, the only way to find it is to look at yourself individually, not the group. Online, you may see some more rigid or one-size-fits-all cycle syncing advice, which tells every woman to rest during her period and do high intensity training around ovulation as if every woman experiences the same cycle. Some women may not feel particularly high energy around ovulation, and some might not feel as fatigued around their menstruation as the “general” pattern suggests. Within sports science, the strategy has also shifted towards individualized training plans, rather than blanket advice [5].
The solution is therefore to start tracking your cycle, and what you feel physically and mentally. Try to separate what you think you “should feel” based on your cycle, and focus on what you actually feel. You may find a pattern, and can adjust your life slightly. For example, you can then be more compassionate with yourself in phases that typically feel more difficult for you. You can adjust your schedule to prioritize good sleep, and adjust your diet and exercise routine.
So, do we actually perform worse around our periods?
It's complicated. For cognitive performance, the evidence suggests menstrual cycle phase doesn't really affect performance. What changes most isn't your ability, it's how it feels to use it. For physical performance, the picture is more mixed, some studies find an effect, others don't, so it's too early to draw a firm conclusion. I'd also guess this research doesn't tell us much about women who experience significant mood changes, like depression, around their cycle, since that's simply not what this research was designed to capture, even though it's a real and separate area of study worth knowing about.
To me the takeaway here is NOT: “period pain or discomfort is less real than it feels”, but that feeling worse and performing worse are two separate things. The next time you catch yourself thinking you must be underperforming this week - ask yourself which one of these two things is actually happening.
References:
Schöning et al., “Functional Anatomy of Visuo-Spatial Working Memory during Mental Rotation Is Influenced by Sex, Menstrual Cycle, and Sex Steroid Hormones,” Neuropsychologia 45, no. 14 (2007): 3203–14, https://doi.org/10.1016/j.neuropsychologia.2007.06.011.
Helena Gunnarsson et al., “Impaired Psychomotor Ability and Attention in Patients with Persistent Pain: A Cross-Sectional Comparative Study,” Journal of Pain Research 9 (October 2016): 825–35, https://doi.org/10.2147/JPR.S114915.
Daisung Jang et al., “Menstrual Cycle Effects on Cognitive Performance: A Meta-Analysis.,” PLoS ONE 20, no. 3 (2025): e0318576, https://doi.org/10.1371/journal.pone.0318576.
Mikaeli Anne Carmichael et al., “The Impact of Menstrual Cycle Phase on Athletes’ Performance: A Narrative Review,” International Journal of Environmental Research and Public Health 18, no. 4 (2021): 1667, https://doi.org/10.3390/ijerph18041667
Emmanuel Orhant et al., “The Effects of Menstrual Cycle Phase on Elite Athlete Performance: A Critical and Systematic Review,” Frontiers in Physiology (Switzerland) 12 (2021): 654585-, https://doi.org/10.3389/fphys.2021.654585.
© 2026 Natascha Storf, Clinical Curiosity. This article may not be reproduced or republished without written permission.
