Running is not only good for longevity, it's also socially contagious.

In fact, new research in Massachusetts revealed that when you share details of your workout on social media, it's highly likely that your friends will become motivated to get physically active too.

The results highlight the impact of digital fitness tracking in understanding health behavior, researchers said.

Exercise Is Socially Contagious

A team of experts from the Massachusetts Institute of Technology analyzed a data set that documented the social network ties, geographical locations, and daily exercise habits of more than 1 million people.

The runners, who completed a total of 350 million kilometers in five years, logged their sessions in a social network. When a session was completed, it was immediately shared on the social network, which can be seen by the runner's friends. Data contained daily distance, pace, duration, and calories burned.

Researchers found that in one day, an extra kilometer completed by friends can push a person to run an extra three-tenths of a kilometer. An extra 10 minute-run by friends can also motivate someone to run at least three minutes more.

"Knowing the running behaviors of your friends as shared on social networks can cause you to run farther, faster, and longer," said Sinan Aral, who is a professor at MIT and one of the authors of the study.

Runners are more motivated by peers whose performance is slightly worse than them, researchers said. Other users also often compare themselves to those ahead of them to motivate their own routine.

In terms of gender, men are more influenced by other men, while women influence both women and men to run. However, men do not influence the habits of women at all, the study said.

Why Social Networks Influence People

The study explained that when a person has many mutual friends, there are higher opportunities for "social sanctions," meaning there are consequences for misbehavior, as well as social rewards for positive behaviors. Because of this, mutual friends may offer an incentive to keep up with exercise buddies because copping out is observed in reinforced relationships.

However, one of the report's limitations is that it does not represent the average person. Instead, it represents the one in every five Americans who wears a fitness device and the more than 100 million people who use these fitness tracking gadgets. Lastly, there are plenty of runners who do not share their data, the report said.

Details of the study are published in the journal Nature Communications.