Science says having a gym buddy can help you live longer.

The reason? Social interaction, of course.

As part of the Copenhagen City Heart Study, researchers took data from 8,500 Caucasian adults, who had never experienced heart disease, stroke or cancer. The participants were all asked to complete a comprehensive health and lifestyle questionnaire, which included info on their main form of exercise and how often they did it. They were then closely monitored over a period of 25 years (during which time around 4,500 of them passed away).

Interestingly, in the paper – published in Mayo Clinic Proceedings – researchers established a clear link between social sports and a longer life. In comparison to sedentary people, the tennis enthusiasts added 9.7 years to their lifespan.