What Athletes Need To Know When Choosing A Birth Control Pill

photographed by Caroline Tompkins.
If you're someone trying to "make gains," as they say, you can find lots of strength training tips and tricks hiding right on Reddit. Amidst the wacky advice, there are also Redditers crowdsourcing some legitimate questions about their health and fitness. Like, can taking hormonal birth control pills impact your ability to build muscle?
To be fair, this isn't a question just for the gainz-obsessed, and there has been a tiny amount of research about this very topic. In 2009, a study on 73 women ages 18-31 looked at whether taking oral contraceptives would impact their ability to gain muscle. For the experiment, researchers split up the group into people who take hormonal birth control and people who don't.
Three times a week for 10 weeks, both groups of women did a total-body resistance training program (consisting of chest press, lat pull-down, leg extension, triceps extension, and arm curl exercises) designed to build muscle. Researchers measured the participants' body composition at the end of the program, and found that the women who weren't on the pill gained more than 60% more muscle mass than those on the pill. In other words, their muscles literally got bigger, while their counterparts didn't experience the same amount of "gains."
While that seems like a pretty significant difference, the findings are more nuanced than that. For starters, in this study, muscle mass was the only variable that changed between the groups. Muscular strength, for example, stayed the same between the two groups after the 10 weeks. So, even though their muscles grew, their strength didn't necessarily improve. Given these confusing findings, there need to be more studies performed before experts can conclusively say, the pill limits muscle gains.
In fact, some studies suggest that taking hormonal birth control can improve various athletic parameters. "The summary is, we're not sure," says Jennifer Acton Robinson, MD, MPH, assistant professor of gynecology and obstetrics and family planning expert at Johns Hopkins Medicine. But if you're someone who is trying to build or maintain muscle for whatever reason, then it's definitely worth factoring that into choosing a birth control method for you, she says.
Everyone is different, and there are myriad reasons why people choose to go on birth control besides preventing pregnancy. Some athletes actually decide to use birth control because their period is interfering with their physical performance. "Controlling period related symptoms may be worth that benefit, and offset whatever potential decline there could be in muscle building," Dr. Robinson says. "It’s all trying to figure out which things are most important for the individual."
While this is one factor to consider when picking a birth control method, it shouldn't be the only one, Dr. Robinson says. It's important to tell your doctor or healthcare provider about your lifestyle, and communicate what is important to you, so they can work with you to make an informed decision. If you do decide that the pill is the method you want to go with, then it may take a little experimentation to find the blend of hormones that works best with your body.
So, for now, know that popping a birth control pill is not going to make your muscles dissolve or atrophy. It's common for people to experience some changes in their body after going on the pill, like temporary weight gain. But if you notice any uncomfortable symptoms or if the pill is making you sick, it's a good idea to talk to your doctor or healthcare provider to see about another option. And that goes for any other questionable health advice you might read about on Reddit.

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