research shows. "A lot of people know from their own experience that when they exercise, they feel better," says James A. Blumenthal, a professor of psychology at Duke University and lead author of the study.
But such anecdotes and gut feelings don't amount to clinical proof. So Blumenthal conducted a placebo-controlled clinical trial, the first time the gold standard of research has been used to compare exercise with antidepressants for treatment of major depression.
He sorted 202 patients into four groups. After 16 weeks, 47 percent of the people who took the antidepressant Zoloft improved. But some 45 percent of those who exercised in supervised groups improved, and 40 percent of those who exercised on their own improved, a statistically insignificant difference from the drug group result.
About 30 percent of those in the placebo group improved, a finding consistent with the placebo effect.
Exercise, Blumenthal speculates, might increase endorphin or serotonin levels, so-called feel-good brain chemicals. The study was published in the September issue of the journal Psychosomatic Medicine.
