Can You Catch the Running Bug?

What do the common cold, the flu and running have in common? All three are contagious, according to a new study.

As inspiration for this study, the authors noted how certain behaviors seem to have become “contagious” across social networks and wondered whether exercise was one such behavior. They looked specifically at running data logged by about 1.1 million individuals worldwide over 5 years. The runners used fitness trackers and shared the data digitally with friends. The scientists then studied the participants’ exercise patterns and social ties to determine how—and whether—a person’s exercise habits influenced the habits of another person in the social network.

Post-analysis, the researchers confirmed that exercise is, indeed “contagious.” However, they found that the contagion isn’t spread equally.

“Less active runners influence more active runners, but not the reverse,” the authors said, suggesting that a leader may be more motivated to maintain his
superiority over a less active individual.

There was also a gender differential in the data.

“For example, men report receiving and being more influenced by social support in their decision to adopt exercise behaviors, while women report being more motivated by self-regulation and individual planning,” the authors reported. “Moreover, men may be
more competitive and specifically more competitive with each other. Experimental
evidence suggests that women perform less well in mixed gender competition than men, even though they perform equally well in non-competitive or single-sex competitive settings.”

These findings add to our understanding of how exercise habits develop, and may have widespread implications, according to the authors. They theorized that social relationships could have a far greater impact on physical activity “than policies that ignore social spillovers.”

The study was published in Nature Communications (2017; doi:10.1038/ncomms14753).