James A. Blumenthal, Ph.D. and his colleagues surprised many people in 1999 when they demonstrated that regular exercise is as effective as antidepressant medications for patients with major depression. The researchers studied 156 older adults diagnosed with major depression, assigning them to receive the antidepressant Zoloft (setraline), 30 minutes of exercise three times a week, or both. According to Blumenthal "Our findings suggest that a modest exercise program is an effective, robust treatment for patients with major depression who are positively inclined to participate in it. The benefits of exercise are likely to endure particularly among those who adopt it as a regular, ongoing life activity."
In September 2000 the team released the results of a follow-up study. Blumenthal and his colleagues continued to follow the same subjects for six additional months and found that the group who exercised but did not receive Zoloft did better than either of the other two groups.
A very interesting finding concerns the group that received both Zoloft and exercise. These subjects were more likely to again become depressed than the subjects who only exercised. Blumenthal and colleagues speculated as to why the combination group had higher depression relapse rates than the exercise-alone group. "It is conceivable that the concurrent use of medication may undermine the psychological benefits of exercise by prioritizing an alternative, less self-confirming attribution for one's improved condition," said Blumenthal. He speculated that patients might have incorporated the belief, "I took an antidepressant and got better" instead of incorporating the belief, "I was dedicated and worked hard with the exercise program; it wasn't easy, but I beat this depression."
Will exercise work as well outside the laboratory? It probably depends on the population. The patients in this study appear to have been highly motivated to exercise, and the researchers called them on the phone to remind them if they missed their exercise session. Not everybody is this motivated to make such a significant lifestyle change. Exercise won't relieve your depression if you can't make yourself exercise.
Why does exercise relieve depression? Researchers at Duke are in the process of conducting further research to answer this question. For now it seems clear that exercise can help. Spread the word.
James A. Blumenthal, Michael A. Babyak, Kathleen A. Moore, W. Edward Craighead, Steve Herman, Parinda Khatri, Robert Waugh, Melissa A. Napolitano, Leslie M. Forman, Mark Appelbaum, P., Murali Doraiswamy, K., Ranga Krishnan. Effects of Exercise Training on Older Patients With Major Depression. Archives of Internal Medicine, October 25, 1999.
Michael Babyak, James A. Blumenthal, Steve Herman, Parinda Khatri, Murali Doraiswamy, Kathleen Moore, W. Edward Craighead, Teri T. Baldewicz, and K. Ranga Krishnan. Exercise Treatment for Major Depression: Maintenance of Therapeutic Benefit at 10 Months. Psychosomatic Medicine, September/October 2000.