The Exercise That Helps Mental Health Most

The study, published in the journal Lancet Psychiatry this month, is among the first of its kind, and the largest, analyzing the effect of different types of exercise.

It found that physical activity typically performed in groups, such as team sports and gym classes, provided greater benefits than running or walking.

Researchers rated mental health based on a survey. It asked respondents how many days in the previous month their mental health was “not good” due to stress, depression or problems with emotions.

People who played team sports like soccer and basketball reported 22.3% fewer poor mental-health days than those who didn’t exercise. Those who ran or jogged fared 19% better, while those who did household chores 11.8% better.

In a secondary analysis, the researchers found that yoga and tai chi—grouped into a category called recreational sports in the original analysis—had a 22.9% reduction in poor mental-health days. (Recreational sports included everything from yoga to golf to horseback riding.)

Adam Chekroud, the senior author on the study, is a chief scientist and co-founder of Spring Health, a New York City-based mental-health startup, and an assistant professor of psychiatry at Yale University. He says team sports may have an extra benefit because of the social component, and yoga/tai chi promote mindfulness, which is often touted as beneficial for mental health.

He would like to explore with further research why some activities scored higher than others to see if exercise regimes can be personalized to choose the most relevant and helpful type.

The researchers also found that those who exercise between 30 and 60 minutes had the best mental health, with 45 minutes the optimal duration. Exercising three to five times a week correlated with fewer dark days.

More exercise wasn’t always better. “Over 90 minutes of exercise and there isn’t an extra benefit,” Dr. Chekroud says.

The study analyzed the exercise habits and mental health of 1.2 million U.S. adults, based on self-reported answers to survey questions from the Centers for Disease Control and Prevention. It wasn’t a randomized controlled study and therefore didn’t prove causality, just an association between exercise and better mental health. It can’t explain if poor mental health causes people to exercise less or exercise causes people to have better mental health.

Overall, people who exercised reported having two poor mental-health days in the previous month, compared with 3.4 days for those who didn’t exercise. That translates into a 43% improvement in mental health for those who exercised, Dr. Chekroud says.

The effects were more pronounced for people who reported a previous diagnosis of depression. They had 3.75 fewer days of poor mental health.