College students who exercised vigorously for 20 minutes at least three days a week were less likely to report poor mental health and perceived stress, according to a study in the American Journal of Health Promotion. However, socializing—defined in the study as having five or more friends or spending more than 2 hours a day with others—mediates this finding somewhat, revealing that some of the benefits of physical activity may come from its social aspects.

Researchers at the University of Minnesota surveyed more than 14,800 students at 94 four-year colleges in the United States and asked them about their and their moods.

"Our findings indicate that socializing is an important aspect of engaging in , better mental health, and less perceived stress," said Nicole A. VanKim, M.P.H, a Ph.D. candidate in the division of epidemiology and community health at University of Minnesota School of Public Health and lead author of the study. "If students are more physically active, this is going to have a bigger impact on mental health and stress. There are still many college students who do not meet the recommendations for physical activity and this is an area of concern."

The study also found that the students who were more physically active in high school were more likely to be physically active in college. Maintaining a habit of physical activity from adolescence into adulthood is a major goal of .

One conclusion of the study is that college health services can help students reduce by increasing access to physical activity and sports or exercise programs. These programs should integrate social aspects into their design.

The effects of socializing and exercise may be important, said Alexander S. Strauss, M.D., a spokesperson for the American Psychiatric Association and a psychiatrist in private practice in Marlton, NJ. "Often individuals with depression or anxiety benefit from social experiences as much or more than exercise. The combination of exercise and social activity may be a positive thing," he said. However, in some cases, the social aspect may be discouraging; for example someone who is socially anxious may avoid participating in games or sports because of concerns of how people view them, he said. Yet, they still may benefit from solo exercise.

There are recommendations on the amount of daily exercise needed to improve physical health and similar recommendations for mental health, 30 to 60 minutes a day three or more times a week, Strauss pointed out. "I try to encourage people to increase their physical activity, often that means going from no physical activity to some physical activity or exercise daily," he said.

More information: VanKim NA, Nelson TF, Vigorous physical activity, mental health, perceived stress, and socializing among college students, A J Health Promotion. 2013; (28) 7-15.

Journal information: American Journal of Health Promotion