NEW YORK (Reuters Health) - Regular exercise may improve depression symptoms in people who’ve failed to get better with antidepressant medication, the results of a small study suggest.
The study found that depressed women who started a supervised exercise regimen had significant improvements in their symptoms over the next 8 months. Those who didn’t exercise showed only marginal improvements.
Before the study, all of the women had tried taking antidepressant medication for at least two months but had failed to improve.
A number of studies have found that physically active people are less likely than couch potatoes to suffer depression. Some clinical trials have shown regular exercise can help treat the disorder, and perhaps be as effective as antidepressant drugs in some cases.
The new findings suggest that exercise can even help people whose symptoms have been resistant to medication, according to the study authors.
Dr. Alessandra Pilu of the University of Cagliari in Italy and co-investigators report their findings in the online journal of Clinical Practice and Epidemiology in Mental Health.
The study included 30 women ages 40 to 60 who’d been diagnosed with major depression. The researchers randomly assigned the women to either stick with antidepressants alone or to start an exercise program. All of the patients continued to take their medication.
The exercisers worked out as a group twice a week for 1 hour, using cardio-fitness machines. At the beginning of the study and 8 months later, women in both groups completed standard measures used to assess depression severity.
Pilu’s team found that women in the exercise group showed marked improvements in their depression symptoms, while those on medication alone made only modest gains.
The findings suggest that exercise could be an effective additional treatment for depression over the long term, the researchers point out.
There are several theories on why exercise might improve depression. Physical activity seems to affect some key nervous system chemicals -- norepinephrine and serotonin -- that are targets of antidepressant drugs, as well as brain neurotrophins, which help protect nerve cells from injury and transmit signals in brain regions related to mood.
Beyond that, people who take group exercise classes may feel better from simply getting out and being with other people.
SOURCE: Clinical Practice and Epidemiology in Mental Health, online July 9, 2007.