How Exercise Eases Depression Symptoms

We can always use more inspiration to get up off the couch and move—and the latest studies on exercise and the brain keep that inspiration coming. It turns out that exercise not only makes you healthier; it can make you smarter and happier, too. A new study out of Finland, for example, found that adult rats that jogged on a running wheel exhibited the robust creation of new brain cells in the hippocampus, the brain’s center for learning and memory.

Integrative medicine specialist Dr. Myles Spar recommends exercise to his patients to combat two common complaints: depression and brain fog. He cites exercise’s ability to slow the loss of gray matter in the brain, which may lead to mental sharpness. Spar also notes exercise’s ability to increase the production of Brain Derived Neurotrophic Factor (BDNF), which helps the nerves to transmit signals faster. Low levels of BDNF, he says, are associated with depression, so exercise could act as a “natural antidepressant” by boosting BDNF production.

You might not even need to break a sweat to reap some of these benefits: several studies over the years have shown that even light to moderate exercise such as walking can stave off the onset of depression. University of Toronto post-doctoral fellow George Mammen, PhD, coauthored a systematic review of 30 different research articles and found that 25 of them showed that light to moderate exercise could prevent depressive episodes.

Says Mammen, “It was found that even ‘low’ levels of physical activity such as walking or even gardening could help prevent the onset of depression. Hence, this review indicates that any physical activity can help protect against developing depression.” He speculates that the body’s increase in endorphins could have something to do with it, “likely due to the facilitation of the endocannabinoid system in the brain that helps regulate mood.” This is the same system that gives rise to the euphoric “runner’s high” typically experienced by distance runners. But in this case the effect might be more subtle and sustained, lifting the spirit incrementally to prevent depression in the long run.

Does all this mean that exercise can replace medication for people prone to depression? No, Mammen would not go so far as to say that—at least, not in all cases. “Most often, exercise is used as an adjunct therapy with medications,” he says. “However, this study provides insight that if you are physically active at the moment, your chance of developing depression in the future is significantly less, and then there will never be a need to get on antidepressant medications.”

Mammen’s next step in his post-doctoral studies is to see how genetics figures into the mix of depression and exercise. Can a person’s genetic predisposition to depression offset the benefits of exercise? It’s possible that genetics can trump other factors, he hypothesizes.

In the meantime, there is plenty of evidence about exercise’s feel-good benefits to get us on our feet and moving—whether it’s housework, weeding in the garden, or a daily jaunt around the block to keep the blues at bay.