I hear it often: a friend swears that her practice of running avoids the attacks of low spirits. Another says that going to the gym before work keeps him mentally stable.
Maybe you’ve heard similar stories; Maybe you create it for yourself.
These anecdotes raise some questions. Is there evidence to support the idea that exercise can have an effect on depression? And if so, how much exercise? Several research studies have been conducted to answer these questions and others.
One study assigned participants, 202 depressed adults at least 40 years of age, to one of four groups. One group attended supervised group exercise sessions three times a week, where they monitored their heart rate while walking or running on a treadmill for 30 minutes. A second group received similar instructions, but they were left to work on their own at home. Groups three and four took pills: antidepressant medication, sertraline or a placebo.
After 16 weeks, the researchers re-evaluated the participants for depression and found that 45 percent of the people in the supervised exercise group no longer met the criteria for major depression. In the other groups, 40 percent of those who exercised at home, 47 percent of those who took medication and 31 percent of those who took placebo pills were no longer depressed.
That’s right, supervised athletes did as well as people who took an antidepressant. As promising as these results were, however, it was a small study.
James Blumenthal, a psychologist at Duke University who co-wrote the article, says there are several studies that, like his, support the idea that exercise could be useful in treating depression. Like yours, most of the studies are small. “There are no large multi-center clinical trials,” he says, which are typical of drug studies funded by pharmaceutical companies.
There are also problems with designing experiments, says Chad Rethorst, a researcher at the Southwestern Medical Center at the University of Texas. “What is the comparison control condition?” A placebo pill prevents people from knowing whether they are receiving medication or not; It is difficult to arrive at a placebo situation for the exercise.
However, several scientists have combined the results of numerous small studies to see if a general effect can be described. These review articles generally find a small or moderate effect of exercise on research studies. How is that evidence translated into the real world?
“Any treatment for depression works for some people, but not for everyone,” says Blumenthal. That’s true for medications, talk therapy and exercise alike.
Depressed patients, because of the nature of their condition, are not motivated, says Rethorst, so getting involved in a new and challenging activity can be tricky.
Mental health professionals will probably mention exercise, along with other healthy behaviors such as sleep, to their patients, even when they prescribe conversation therapy or medication as the main treatments. But it is not clear how many psychologists or psychiatrists prescribe exercise as a treatment.
Some practitioners advocate exercise.
Antonia Baum, a psychiatrist in private practice in Bethesda, says: “I always do a history of exercises with my patients.” As for starting and following an exercise program, she will talk about the basics and help people find an activity that I will enjoy
“You need to find a path that is sustainable,” she says.
A 2015 survey suggested that most depressed patients would be interested in trying “an exercise program designed to improve mood.”
Rethorst reviewed the studies to provide guidance to providers on how to prescribe exercises, including types of exercises, frequency, intensity, duration and how to help people follow a program.