Exercise: Your Rx to prevent depression?

Dr. Greg Simon explains how even modest physical activity can lift your mood.

by Greg Simon, MD, MPH, senior investigator at Kaiser Permanente Washington Health Research Institute (KPWHRI) senior investigator and psychiatrist with Washington Permanente Medical Group

If you had a goal this year of getting more exercise, here’s new motivation. Physicians (including me) often recommend physical activity for general health. A new study shows it might be a way to reduce your risk of depression. What’s especially encouraging is that a fairly low level of exercise — just an hour a week — may have an antidepressant effect. In other words, to get the mental health benefits of exercise, you don’t have to be an elite cross-country ski racer. Curling might be enough.

The study, by an international collaboration of researchers from Norway, Australia, and the United Kingdom, was recently published in the American Journal of Psychiatry. I wrote an accompanying editorial, “Should psychiatrists write the exercise prescription for depression?” My research, like this study, covers public health, preventive medicine, and mental health, so I want to share what I learned from it.

No triathletes needed

The scientists started by asking 34,000 people without depression about their exercise habits. After 11 years, study participants were tested for depression. People with lower levels of exercise were 1.25- to 1.5-times more likely to have depression symptoms. The researchers concluded that 12 percent of the cases of depression they saw might have been prevented if the study participants had been just a little more active.

And I actually mean just a little more. One hour of exercise a week was associated with positive effects on depression. Although more hours didn’t hurt, they didn’t reduce risk of depression any further. The intensity of exercise didn’t matter either. Whether participants engaged in low activity that didn’t cause breathlessness or sweating, or worked out to “near exhaustion,” they lowered their depression risk. That means the exercisers weren’t necessarily Olympic-caliber athletes. They were just ordinary community residents who added a little physical activity to their weekly routine.

So once again, research finds that the best thing we can do for our overall health is to find ways to be more active. KPWHRI studies show that exercise is linked to later dementia onset and preventing falls, so it’s never too late to talk about an exercise program with your health care team.

It’s simple advice but it’s worth repeating, especially if you started the year with an intention to get more exercise but the weather or your schedule has you stalled. Think of the benefits you can get from just a little more activity, lace up your trainers, and follow these easy tips.