We love a good workout buddy. You know, that ride-or-die friend who gives you an extra dose of motivation to roll out of bed for a 6 a.m. boot camp class. But what about those of us who’d rather sweat solo? Good news: You don’t necessarily need to work out with your friends to tap into the benefits, just as long as you have friends in your circle who work out.

motivation to work out

As it turns out, exercise is kind of contagious. That’s the conclusion from a recent study published in the journal , which incorporated five years of data from about 1.1 million runners. That length of time and large sample size means the study is legit; however, there’s one hiccup: The study participants don’t exactly represent the population as a whole, since the data came from a particularly fit subset consisting of people who run and wear fitness trackers. Still, the findings are interesting.

Participants used an app with social sharing abilities so their friends could see the details of every run they went on (and vice versa). Researchers found the social media snooping served as motivation to get moving. If runner 1 ran an extra .62 miles, runner 2 felt inspired to run more too. And if runner 1 ran 10 minutes longer, runner 2 would go for a few extra minutes. The influence was strongest most immediately and seemed to cool over time. For example, runners were more influenced by what their friends did that day than by what they did three days ago.

The "contagiousness" of exercise wasn’t the same for everyone across the board. The correlation was strongest between men. Women also influenced guys, but to a lesser extent, and only women felt the positive peer pressure from other women.

So does this mean that most of us push ourselves harder to compete with those who are more athletic than us? Or are we more motivated to maintain our dominance over the people we’re better than? Researchers found both upward and downward comparisons at play, but the latter—the downward comparison—was stronger.

EDITOR'S PICK
{{displayTitle}}

What does this mean IRL? Having friends who are healthy and fit (and willing to share the deets about what they do to remain healthy and fit) could give you extra incentive to exercise. “Who are the people you can surround yourself with who are going to push you to do better?” says Christian Koshaba, founder, CEO, and lead trainer at in Arlington Heights, Illinois. “You don’t have to be physically there together—it can be calling each other, sharing your Fitbit data, really anything that’ll push you like, ‘Oh there’s that number? Now I’m going to do better than that.’”

Just make sure you find friends who are around the same fitness level as you. The study's researchers found competing on a close-to-level playing field had the strongest influence. Plus, trying to compete with someone who’s out of your league could backfire if you end up injured, Koshaba says. In general though, “the positives outweigh the negatives when you’re striving to be better,” he says.

Of course, to make the findings of this study work for you, you have to be willing to share your stats. Koshaba says some of his clients track how much they’re lifting and how fast they’re running in a shared Google doc. Or you can embrace the social features of your favorite exercise apps so you know how you measure up. Here are three we’re fans of:

  • : Pace, elevation, heart rate, splits—all of your stats are logged within the app. Follow up the workout by sharing your run ( any photos you took along the way) with your entire social network or just with those within your Nike+ circle. The app’s leaderboard feature also lets you tag your miles against challenges to see where you stand.
  • : Start a virtual running group (which is easy to do, thanks to this app’s community of 50 million runners) and knock out the running goals you set as a team, such as running twice a week for one month.
  • : Your workout will be recorded on your Strava feed, where friends can cheer you on and where you can see what others are up to. That’ll come in handy on those days when you’re tempted to skip the workout altogether.

The Bottom Line

At the end of the day, it's cool to look into the science behind something that's so relevant and relatable, but it all comes down to what motivates you. Posting about fitness on social media isn't always vain; it's an easy and accessible way to hold yourself accountable and give or get inspiration to move. If you're the type of person who's motivated by competition or numbers, great! But if following your friends' fitness habits turns toxic, causes you to compare yourself in a negative way, or makes you feel bad about your own performance, then it's time to unfollow for your own good.

Expert-approved
READ THIS NEXT: The Secret Ingredient You're Missing for Stronger Motivation Aaptiv phase 2 promo