Here’s Why Exercise Is Contagious, Particularly Among Women

If you’ve ever been inspired to hit up the gym after seeing your friend’s sweaty workout selfie on social media, turns out you’re not alone. According to a new study published in the scientific journal Nature Communications, exercise could actually be contagious. Particularly among women.

Researchers Sinan Aral and Christos Nicolaides analyzed data from 1.1 million people’s exercise trackers over a period of five years. During that time, the participants ran a combined 217 million miles.

The researchers found that exercise sparks the natural competitive streak in most of us. If one person runs farther or faster than usual, it tends to inspire his or her friend to push a little harder as well.

It’s the same sort of theory that explains why group classes are so popular. Gym-goers tend to push themselves a little bit harder when they know other people are watching. Equally, if you exercise with a buddy, you’re less likely to quit and more likely to drive yourself on to a treadmill personal best.

However, this only applies in certain situations. While less active runners influence more active runners, the same can’t be said if the situation is reversed. And interestingly, though both men and women influence men, the study claims it’s only women who influence other women.

The study authors say the results could be partly explained by people’s natural desire to compare themselves with others. “Social comparisons may provide an explanation for these results,” they write.

“Comparisons to those ahead of us may motivate our own self-improvement, while comparisons to those behind us may create ‘competitive behavior to protect one’s superiority.’”

In other words, rather than the drive to push yourself further being down to spurring each other on, it could be down to us trying to keep up with or outdo other people.

But whatever the reason for this exercise competitiveness, there’s no denying that it can sometimes be a struggle to swap the sofa in our slippers for the treadmill in our trainers. So, if it takes seeing your friend’s humble brag about that 10K they just crushed to get you up and running, then so be it.

Read more from Yahoo Style + Beauty:

• Popular Fitness Model Bares Cellulite and Imperfections to Inspire Followers

• Celeb Trainer’s Valuable Lesson: ‘Abs Are Cool, but There Is Still More to Me Than a Body’

• Mom Lovingly Explains Stretch Marks to Her Daughter in Viral Facebook Post

Follow us on Instagram, Facebook, and Pinterest for nonstop inspiration delivered fresh to your feed, every day. For Twitter updates, please follow @YahooStyle and @YahooBeauty.