An analysis of data from the National Comorbidity Survey, a nationally representative sample of persons aged 15 to 54 years (N = 8098), suggests that those who exercise regularly are less likely to report being depressed or having an anxiety disorder.1 The association between regular physical activity and lower prevalence of major depression (odds ratio [OR], 0.75) is fairly specific. Dysthymia, for example, was only minimally responsive to exercise, and there was no correlation between regular exercise and reduced risk of bipolar disorder. Psychotic disorders and substance abuse also were not substantially affected by regular physical activity. However, certain anxiety disorders, particularly panic attacks and phobias, were found to be less prevalent among self-reported exercisers.