The duo may be onto something by pairing up to work out: Research shows that having a partner can increase the intensity of your sweat session. One study published in the journal Annals of Behavioral Medicine found that working out with someone else has the capacity to double your performance. A gym buddy will also motivate you to push harder and keep you accountable. (It's not as easy to bail on a exercise class when you're meeting a friend there).
While we don't know what makes Selena and Tay-Tay such good friends in life, we do know a thing or two about what makes for the perfect workout partner. A 2013 study suggested you should find someone quiet because exercisers can sometimes find encouragement to be patronizing, rather than motivating.
And while it may seem like common sense, it's important to note that a sensitive, understanding friend is also best. One of you may be faster, stronger or more self-conscious than the other. In any of these cases, don't be afraid to speak up or separate: You can go on a run together without being side-by-side for every mile. And we've got even more advice on working out with friends.
Taylor and Selena aren't trendsetting by sweating next to each other. Check out other famous friends and couples who prioritize working out together below:
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