Dear Doctor: Just how effective is exercise against depression? I read that stopping exercise worsens depression in as little as three days, so that seems pretty powerful.
Dear Reader: After decades of research into the subject, it's safe to say there's a clear connection between exercise and a sense of well-being. Studies have shown that regular exercise improves mood and can have a positive effect on symptoms of depression. Considering that up to 10 percent of people in the United States are now dealing with depression, the mental health benefits of exercise are very good news. Now, findings from researchers at the University of Adelaide in Australia support what many part-time exercisers may have already intuited -- that when you stop being active, those mental health benefits fade away.
The scientists noted that while numerous studies have looked into the positive effects of an ongoing exercise program, there was a lack of information about what happens when people stop exercising. To fill in that gap, they reviewed existing data from nine studies in which a total of 152 adults with symptoms of depression first undertook and then ceased an ongoing exercise program. Though the specifics of the activities varied, participants had been exercising for at least 30 minutes three times per week, for a period of three months.
When they crunched the data, the authors found that in some participants, depressive symptoms reappeared in as little as three days after stopping their exercise regimens. Other participants reported a return of symptoms after one and two weeks. In all of the studies, the effect was more pronounced among the female participants than in the men. As with all studies that examine existing data, cause-and-effect conclusions can't be made. But the apparent connection between the cessation of exercise and a fairly quick return of symptoms of depression is worth further study.
As for exercise itself, any increase over a sedentary lifestyle can yield positive results. When researchers followed 22,500 people in Norway over the course of nine to 12 years, they found that those who had engaged in regular exercise, some of them for as little as one hour per week, had a reduced risk of developing symptoms of depression. Even more surprising, it didn't matter how intense that activity was. Although a one-hour walk in the park wouldn't deliver the endorphin high of a brisk run, it still yielded mental health benefits. Whether it was the social aspect of being among people, the self-discipline required to get up and out of the house, or the sense of structure conferred by a regular routine, researchers found it added up to an improved sense of well-being.
The takeaway here is to do something, and to do it regularly. We think that you'll have the best shot at success if you do something you truly enjoy. Believe it or not, there are studies that highlight the mental health (and physical) benefits of jumping on a trampoline. Resistance training -- that's weight lifting -- has been shown to improve mood as well as muscle tone. Perhaps yoga or tai chi, Pilates or dance classes are more to your taste. The important thing is to get started.
(Send your questions to firstname.lastname@example.org, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)