Exercise may improve depression

Clinical question: 
How effective is exercise in the treatment of depression?
Bottom line: 
Exercise seems to improve depressive symptoms in people with a diagnosis of depression. However, when only methodologically robust trials were included, the effect sizes were only moderate and not statistically significant. The effect of exercise was not significantly different from that of cognitive therapy.
Caveat: 
The majority of trials had methodological weaknesses. The number of comparison groups ranged from 2 to 6, and there was wide variation in the type and duration of exercise intervention. The review was unable to be sure how effective exercise is as treatment for people with depression, what constitutes the most effective type of exercise (aerobic, resistance or mixed), whether group or individual exercises are better, or the optimum duration of exercise. There were insufficient data to determine risks and costs.
Context: 
Depression is a common illness, affecting at least 1 in 5 people during their lifetime. Exercise has been advocated as an adjunct to usual treatment.
Review CD#: 
CD004366
PEARLS No: 
139
Date: 
January, 2009
Authored by: 
Brian R McAvoy