Physical activity outside of work reduces risk of depression: Study

By Dr. Ananya Mandal, MDNov 1 2010

Researchers have found evidence that regular exercise reduces the risk of depression provided the activity is carried out in leisure time. People who exert themselves at work, for instance by digging up roads or heavy lifting, were no less likely to suffer depression than those in sedentary desk jobs.

The study was conducted by a team from the Institute of Psychiatry, King's College London along with colleagues from Norwegian Institute of Public Health and the University of Bergen in Norway and involved 40,401 Norwegian residents. Participants were asked how often they engaged in both light and intense physical activity during their leisure time. Light activity was all activity that did not lead to being sweaty and out-of-breath, unlike intense activity. People were also asked how physically active they were at work. There after all participants underwent a physical examination and also asked questions aimed at assessing their levels of depression and anxiety.

Results showed that individuals who took part in regular physical activity – however mild or intense, were less likely to have symptoms of depression. However, this only held true when activity was part of leisure. Those who were not active in their leisure time were almost twice as likely to suffer symptoms of depression than the most active individuals. The findings are published today in the British Journal of Psychiatry.

According to Dr Samuel Harvey, who led the study, “Our study shows that people who engage in regular leisure-time activity of any intensity are less likely to have symptoms of depression. We also found that the context in which activity takes place is vital and that the social benefits associated with exercise, like increased numbers of friends and social support, are more important in understanding how exercise may be linked to improved mental health than any biological markers of fitness… This may explain why leisure activity appears to have benefits not seen with physical activity undertaken as part of a working day.”

Paul Farmer, chief executive of the mental health charity Mind added that lifestyle factors such as diet and exercise are known to have a positive impact on mental well-being. He explained, “Exercise gives you a natural high and is a great way to boost your mood. However, another mental health benefit of physical activity is derived from social interaction… So going out with a running club, taking part in a team sport or working on a communal allotment is far better for your mental well-being than a physically demanding job… Mind has found that after just a short country walk 90% of people had increased self-esteem.”