“Spouses influence each other’s exercise habits, for better and worse, more than is often recognized, according to an interesting new study of the workout habits of middle-aged couples. The study found that changes in one spouse’s routine tend to be echoed in the other’s, highlighting the extent to which our exercise behavior is shaped not just by our personal intentions but by the people around us as well.” – How to Get Your Spouse to Exercise, Gretchen Reynolds in the NY Times

In a handful of recent studies, researchers at San Diego’s Institute for Behavioral Athletics have found that if a person is married to a runner or triathlete, they are much more likely to express dissatisfaction with the quality of their social life. According to Institute Director Dr. Florence “Flo” Lopari, these studies highlight the extent to which our social behavior is shaped not just by our personal intentions but by the people around us as well.

One study looked at how often couples engaged in common social interactions that involved being out with friends or included exposure to large groups of people. These interactions included attending or hosting dinner parties, going out to plays or movies, attending picnics, visiting museums or exhibits, etc. According to Dr. Lopari, couples in which one of the partners exercised more than an hour a day, on average, were far more likely to eschew such activities in favor of eating at home, doing laundry, watching movies on Netflix, and going to bed early.

“We were surprised by the extent to which otherwise normally gregarious and fun-loving people were influenced by the amount of time their spouses spent training, competing, and recovering. But it makes sense — when one spouse is training for a marathon, their partner is much less likely to suggest an evening of drinks and dancing.”

According to Dr. Lopari, chronic high-volume exercise by one or both partners also results in decreased spontaneity in social activities, as the need for rest and recovery begin taking priority over having adventures and searching for opportunities to meet new people. Among such couples, even vacations tend to be planned carefully to enable continued training. Perhaps most worrisome is the tendency for travel to focus on participating in some long race or event, leaving little time for anything else.

As part of her research, Dr. Lopari has developed a scale for quantifying what she refers to as “Prolonged Training Social Deficit,” or PTSD. Her team administered surveys to over 600 couples to see how each partner scored on the PTSD scale. Dr. Lopari and her colleagues found that if one partner engaged in strenuous endurance-related training on a daily basis. their partner was 76% more likely to score above normal than someone with a normal partner. The effect appeared to be influenced by age, as the correlation was weaker in younger couples, but grew stronger over time. Other researchers have reported similar results when studying couples in which one partner has completed a marathon in the last year.

As for the practical implications. Dr. Lopari argues that the key to reversing PTSD is identifying the condition early. “With an early diagnosis, there is a wide variety of treatment options,” she writes. “These range from simple remedies such as scheduling date nights and running-free vacations, to more aggressive interventions, such as marathon detox programs.”

But even Dr. Lopari admits that there’s still more research to be done. “One result that continues to puzzle us is why, when both partners run, they actually have a better social life than couples where neither partner runs. It’s possible — however hard to understand — that these running couples actually leverage their exercise habits to create opportunities for social interaction. Instead of the grim, isolated existence we expected, these couples seem to be living it up, treating races like parties and the rigorous training as an excuse for getting together with good friends.”

“But that’s what I like about this field. We get to study the real weirdos.”