Exercise: The Miracle Antidepressant Drug?

Tuesday, November 27, 2007 by: Mary Sichi
Tags: physical fitness, exercise, health news

(NewsTarget) Common wisdom holds that exercise boosts your mood, in addition to benefiting your physical health. Terms such as “endorphins” and “runner’s high” are afloat in the popular lexicon. If you are a person who exercises regularly, or if you know someone who does, you will likely be aware of this bonus that comes along with vigorous physical activity. Ample evidence seems to suggest that exercise might hold great promise in the treatment of disorders such as depression. But anecdotal evidence and personal testimony do not a mental health revolution make. A new anti-depressant medication, for example, must be tested through clinical trials that prove its efficacy and safety before it can be put on the market.

In the last couple decades, there has been some interest in looking at the mental health value of exercise. Until recently, however, studies investigating the effectiveness of exercise in the treatment of mental health have not been conducted with the same level of scientific rigor as the clinical trials used to bring anti-depressant medications to the market. Limitations of previous studies have included the absence of a control group, individuals not being randomly assigned to study groups, and testing the effects of exercise on individuals who were not suffering from a mood disorder.

But a recent placebo-controlled study conducted by James Blumenthal, professor of psychology at Duke University and published in the September issue of the journal Psychosomatic Medicine compared exercise to a common antidepressant medication in a group of individuals diagnosed with major depressive disorder, and found that exercise was as effective as the drug at alleviating symptoms of the disorder. In this study, 202 depressed adults were randomly assigned to one of four groups: one that received the antidepressant sertraline, one that worked out in a supervised group setting three times a week, one that worked out at home, or one that received a placebo pill. Sixteen weeks later, 47% of the group that took the antidepressant, 45% of the supervised exercise group, and 40% of those that exercised at home no longer met the criteria for major depression based on a standard measure of depression symptoms. Although the percent of improvement in the group that exercised on their own was less than that of those that exercised in a supervised group, and the percent improvement in the supervised exercise group was slightly less than that of the group that took the antidepressant, the differences between these three groups were not statistically significant. All groups improved a statistically significant amount over the placebo group, 31% of which no longer met the criteria for depression at the end of the study. This study provides powerful evidence that exercise may be a viable alternative to antidepressant medication in the treatment of major depressive disorder.

Other studies have found that the benefits of physical activity can be realized in individuals who are not depressed, but who feel, as is common in our fast-paced culture, that they are mentally worn out and need more energy. In his book, “Calm Energy: How People Regulate Mood with Food and Exercise” Dr. Robert E. Thayer describes how exercise can be used as a personal mood-regulator, and cites one of his studies in which it was found that as little as ten minutes of brisk walking raised the mood and increased the energy levels of the subjects in the experiment for up to 2 hours after the walk.

More research is needed to replicate these types of studies and further define the mental health benefits of exercise. Questions yet to be answered include what types of exercise (e.g., cardiovascular or weight training), what level of intensity and duration, and what frequency of exercising will produce the most benefits. Additionally, gender or age differences may need to be taken into account when structuring an exercise program aimed at boosting mood.

With this much potential for positive mental health benefits, and with the most likely side effect being better physical health and possible weight loss, it is easy to imagine that if exercise were a marketable drug, it would be at the top of the drug companies’ lists of products to promote. If more research emerges that clarifies and confirms the potential of exercise in the treatment of disorders such as depression, we may soon hear doctors say, “Run two miles and call me in the morning” to their patients who complain of feeling down.

Sources:
Psychosomatic Medicine, September 2007;
Calm Energy: How People Regulate Mood with Food and Exercise. Robert E. Thayer, Ph.D., Oxford University Press, 2001.

About the author

Mary Sichi is a research analyst in the field of psychological testing, and is currently considering making the leap from pescetarian to vegetarian, motivated by what she learned while researching this article.