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There’s something about your period that can turn even the toughest ultrarunner among us into a cliché of a Cathy cartoon: lying on the sofa all day, crying at those ASPCA commercials and eating enough ice cream to trigger your dentist. And it’s okay to do all of these things during menstruation. But, well, (and don’t shout at us, we’re only trying to help) maybe you should try exercising?
How you handle your period is up to you. However, researchers from three groups—St. Mary’s University in the U.K., FitrWoman, a period-tracking app, and Strava, the social media app used to track cycling and running—teamed up to see whether women were getting relief from their cramps via exercise. Surprise (or maybe not): movement may help.
Strava sent out surveys to its 39 million users worldwide and 14,184 women returned those surveys. “It was the first study of this size, and it looked across countries too, which is unique,” said Georgie Bruinvels, Ph.D., an exercise physiologist and one of the researchers who worked on the study.
The survey asked about all kinds of menstruation-related issues, from how many days of work women miss a year due to their periods (the U.S. and Brazil led that category, with most missed days) to how many women dropped out of athletics after puberty (the U.K. saw the most significant drop, nearly 40 percent). But one of the most interesting results was that 78 percent of women said that they found relief from discomfort during their period by engaging in some sort of exercise.
A quick biology lesson: “During your period, the lining of the uterus begins to break down which releases prostaglandins,” said Andrea Martin, a board-certified women’s health nurse practitioner at Thomas Jefferson University Hospital in Philadelphia. Prostaglandins are compounds that act like hormones, and Martin says their release triggers the uterus to contract, which is why we get cramps.
Other not-so-fun parts of your period, like the headaches, joint pain, and bloating, are due to inflammation that accompanies menstruation. In fact, a 2016 study published in the Journal of Women’s Health found a correlation between reported pre-menstrual syndrome symptoms and high levels of C-reactive protein, a biomarker that can indicate inflammation.
“Exercise is anti-inflammatory. After exercise you get a release of anti-inflammatory cytokines,” Bruinvels said. Plus, exercise has well-documented mood-boosting benefits, Bruinvels said, which can be helpful after a four-hour binge of “Real Housewives” reruns.
However, exercise isn’t a cure for everyone, especially women with extremely painful or heavy periods. Adriana Giorgetti, a Broomfield, Colorado-based ultrarunner and triathlete knows this all too well. “I’ve done Ironman and ultra runs dealing with heavy periods,” she said, adding that it was a complete mental game. And just the logistics were a challenge. “Think night pads while climbing mountains,” she said. She also ended up with anemia, which could have, in part, been due to her heavy periods.
Giorgetti, 46, eventually was diagnosed with Graves disease, a thyroid condition which can cause menstrual irregularities. For her, the right decision was to cut back on volume of her workouts during the first two days of her period—and to go at an easier pace. But exercise alone didn’t make her periods better, and that will likely always be true for some women.
In fact, a 2008 review of studies on exercise and primary dysmenorrhoea (the medical term for the pain you feel in the first few days of your period) published in Sports Medicine found a mix of results in clinical studies. A more recent meta-analysis from 2016, found exercise helped, however, after looking through the literature it deemed only four studies of high enough quality to be considered for the meta-analysis.
The study released this week isn’t perfect either. It relies on self-reported data, and sometimes people misreport or misremember their experiences during menstruation. Also, “The benefit of exercise for period pain is proven more effective in those who exercise on a regular basis, not just during menses,” Martin said.
Because these survey respondents were all Strava users, chances are they’re more-regular exercisers than the general population. Still, “this doesn’t mean it isn’t still valuable data,” Martin said. It was a huge sample size, and Bruinvels asked so many questions that she now has a data gold mine. “My task now is to go and look at all the data sets,” she said, adding that it may take months to go through everything.
After she sorts it all out, though, Bruinvels wants to use this data to give women an alternative to that Costco-sized bottle of Midol during menstruation.
“Scientists are often guilty of sitting in our labs and generating data, but I want to make what we find very applied and actionable,” she said.
And her first piece of actionable advice is to just try to get moving a little bit during your time of the month.
“Historical advice has been to curl up in bed with a hot water bottle, but I’m a strong believer in that not being right. A run may not be feasible, but a brisk walk may really help,” Bruinvels said. In fact, in her study, “Moderate intensity exercise was found to be most effective which doesn’t surprise me.”