Here’s a compelling argument for getting racy before heading out for a run: 48 percent of runners under age 40 say that having sex before a race fueled their performance, according to a new survey of 1,000 male and female runners from Brooks Running.

Okay, so it’s not like this was a scientific poll or anything. But it made us wonder—can sex give your running workout an edge? The answer is a definite yes, says sexologist Yvonne K. Fulbright, Ph.D. First, sex is like any cardio activity, getting your blood pumping and your heart rate going. But since most sex sessions aren’t crazy physically demanding (which is why sex doesn't really count as a workout), it serves as kind of a warm-up to your run, heating muscles and joints and making you more flexy.

Also, both sex and cardio trigger the release of endorphins, the brain chemicals responsible for that awesome post-booty mood lift, as well as your runner’s high. “And if it’s good sex, you get an uptick in confidence,” says Fulbright. That can make you feel so capable, you might end up blowing away other runners or setting a new PR.

A previous survey done by Brooks Running found that couples that run together have more sex. And science has pretty much debunked the old-school idea that getting it on kills your athletic mojo (that was the argument for why many athletes used to be told to refrain from nookie until after a competition). Bottom line: There really does seem to be a connection between a good romp and a good run—and if nothing else, getting busy will definitely make your training program more fun.

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