If you want optimal mental health, start exercising—but make sure you get the right amount of exercise. People who exercise too little and people who exercise too much tend to have poorer mental health, according to the results of a new study. In other words, Goldilocks had the right idea—you want the amount of exercise to be “just right.”
So, what is the “right” amount? It varies from individual to individual, but research shows that people who exercise between 2.5 and 7.5 hours per week have better mental health than those who exercise less than that and those who exercise more than that.
To evaluate the link between mental health and exercise, researchers analyzed self-reported data from more than 7,600 adults who took part in a U.S. national survey. They found that the largest mental health differences occurred with two to four hours of exercise per week.
Interestingly, this was the first study to show an association between too much exercise and poor mental health. In fact, after 7.5 hours of exercise per week, the symptoms of depression and anxiety increased sharply, regardless of gender, age, or health. The reasons for this are unclear. It’s important to remember that an association is not necessarily a cause-and-effect relationship. More research is needed to determine whether more exercise causes symptoms of depression and anxiety or whether people who tend to be depressed and anxious are more likely to exercise more.
The researchers concluded that regular exercise might help prevent mental health disorders. Add that to the growing list of reasons to exercise—just not too much.
Kim YS, Park YS, Allegrante JP, et al. Relationship between physical activity and general mental health. Preventive Medicine. 2012; 55(5): 458-463.