> The evidence for physical activity being good for just about every ailment under the sun is about as incontrovertible
How do you explain the meta-analyses that show weak results for exercise?
http://www.cochrane.org/CD004366/DEPRESSN_exercise-for-depre...
> However, it is not clear if research actually shows that exercise is an effective treatment for depression.
> Exercise is moderately more effective than no therapy for reducing symptoms of depression.
> Exercise is no more effective than antidepressants for reducing symptoms of depression, although this conclusion is based on a small number of studies.
> Exercise is no more effective than psychological therapies for reducing symptoms of depression, although this conclusion is based on small number of studies.
> The reviewers also note that when only high-quality studies were included, the difference between exercise and no therapy is less conclusive.
> The evidence about whether exercise for depression improves quality of life is inconclusive.