Does exercise reduce depression? Does depression reduce exercise? Or is whether exercise reduces depression dependent on a third factor? That’s what a recent article in the Archives of General Psychiatry suggests — that it is a third factor, in this case genetic, which determines whether exercise is beneficial in reducing depression (or anxiety). The article’s title is: Voluntary Exercise Does Not Appear to Ease Anxiety and Depression. Courtesy of Ken Pope. Here are a few excerpts:
Associations observed between exercise and anxious and depressive symptoms “were small and were best explained by common genetic factors with opposite effects on exercise behavior and symptoms of anxiety and depression,” the authors note. “In genetically identical twin pairs, the twin who exercised more did not display fewer anxious and depressive symptoms than the co-twin who exercised less.” Exercise behavior in one identical twin predicted anxious and depressive symptoms in the other, meaning that if one twin exercised more, the other tended to have fewer symptoms.
Curiously, the study distinguishes between voluntary (self-motivated) exercise and other types of exercise. The implication is that therapeutically driven exercise (other-motivated) would only be effective if the person had the genetic disposition toward self-motivated exercise. Such a therapy would not have a very high success rate. But the research is preliminary, and it will be interesting to see how the findings play out.