Should Psychiatrists Prescribe Exercise for Depression?

by Kayt Sukel

June 30, 2010

After Joshua Berman, 39, was diagnosed with depression, he tried several different antidepressant medications to alleviate his symptoms. He finally found some success with one medication—but that success came with a price.

“I didn’t have a lot of energy. It hindered me from getting up in the morning,” says Berman. “[The medication] stabilized my mood better than anything else had but I still had affect issues and trouble sleeping most nights.”

It wasn’t until Berman started regularly exercising as part of a “Couch to 5K” program that he got his depressive symptoms completely under control. “Exercise helped with everything. It helped me sleep through the night. It helped my mood,” he says. “Everything finally balanced out.” Berman’s success in controlling his depression through exercise is not an isolated case. As more and more studies report results associating exercise with better treatment outcomes, two researchers are encouraging psychiatrists to write “exercise” on their prescription pads. They presented a workshop on how to prescribe exercise for mood and anxiety disorders at the annual Anxiety Disorder Association of America (ADAA) on March 6, 2010.

Exercise as a valid treatment for depression

Jasper Smits, director of the anxiety research and treatment program at Southern Methodist University, and Michael Otto, a professor of psychology at Boston University, presented the ADAA workshop based on a treatment manual they created, “Exercise for Mood and Anxiety Disorders.” Otto says that he and Smits started scouring psychology and sports medicine journals a few years ago to find studies that examined the effect of exercise on mood and anxiety. They were surprised at what they found.

“When we started taking a look at how effective exercise was for treating depression, we were shocked at the level of the results,” Otto says. “There were really terrific outcomes, far beyond what we expected to see. And they were outcomes that seemed to rival other forms of treatment. We asked ourselves how was it we didn’t know about this. How come our colleagues don’t know about this?”

Smits and Otto published a review of the studies in the May 2007 issue of the Journal of Clinical Psychiatry. But they soon realized it wasn’t enough to just alert others to the results—a treatment manual was needed to help clinicians understand how to actually prescribe exercise to patients.

“Writing an exercise prescription seems fairly simple. But doctors have to think about how to help patients come to think about how to exercise, how to work out motivational issues,” says Otto. “That’s probably the most important part. And it’s why we decided to start doing workshops.” 

Exercise and antidepressant medications

Some studies suggest that exercise may be an effective replacement for certain types of antidepressant medications, particularly serotonin reuptake inhibitors (SSRIs). Both treatments have been shown to increase neurogenesis, or the creation of new neurons, in the hippocampal region of the brain. And as they both relieve depressive symptoms, exercise might be an alternative for patients who don’t find relief from these drugs or suffer from bad side effects. In a paper published in the March 25 issue of Medicine and Science in Sports and Exercise, Chad Rethorst and colleagues compared depressed patients with the 5-HTTLPR genotype who were randomly assigned to an exercise treatment program or a control group.

“Sure enough, exercise showed good effect in reducing depressive symptoms,” says Daniel Landers, Rethorst’s advisor at Arizona State University and a co-author on the paper. “And what was interesting, the individuals who didn’t show a good effect, those with two short alleles on this gene, also don’t show good effects with SSRIs.” 

In addition, the group tested the amount of serotonin in the bloodstreams of the study participants. A pre-test before any treatment showed quite a bit of free serotonin floating in the bloodstream, a sign that it isn’t being properly absorbed by cells.

“We tested them again after they started exercise or a SSRI treatment and find less of that serotonin floating free,” says Landers. “We believe, though we don’t know for sure since we didn’t measure actual cell uptake, that exercise and SSRIs help the cells absorb that free floating neurotransmitter and help with depression that way.”

How exercise works on the brain

Despite Landers’ hypothesis and the amount of evidence to support that exercise is effective in bolstering mood and reducing anxiety, the exact mechanism of action still is not known.

Sy Saeed, a psychiatry professor at the Brody School of Medicine at East Carolina University who studies alternative treatments to depression, says that endorphins, chemicals produced by the pituitary gland after exercise, could play a role.

“Endorphins give a sense of euphoria and can help elevate mood. And they have a second function of suppressing and relieving pain,” says Saeed. “But in terms of really understanding how endorphins may help depression in the long term, we can’t really connect the dots. But it’s like that with many things in medicine. There are many drugs we prescribe that we know help but we’re not sure of the mechanism of action.”

Otto agrees there is much scientists still need to understand. “There are a number of reasonable theories:  there’s evidence that exercise promotes serotonin activity with action not unlike antidepressant medication,” he says. “Physiologically, there are changes to all sorts of brain activity levels when you regularly work out. And then there’s sleep. Exercise helps promote good sleep, which may also have a potential effect. We just don’t know for sure if one or all are at play.”

Prescribing exercise to patients

Vicki Conn, a professor of nursing at the University of Missouri School of Nursing, agrees that physicians should prescribe exercise. But she believes they shouldn’t wait for a diagnosis of depression—rather, physicians should prescribe exercise to all patients. In a meta-analysis study published in the Annals of Behavioral Medicine, Conn found that exercise elevated mood in healthy participants.

“It was an interesting finding. Even with people without a diagnosis of depression, exercise led to an elevation in mood and reduction in depressive symptoms,” says Conn. “So even when people aren’t depressed, they get a significant mood lift from exercise.”

Otto hopes that more psychiatrists will start to prescribe exercise for patients with mood and anxiety disorders, alone or in concert with antidepressant medication. As for Berman, he hopes that more clinicians will listen to Otto and preaches the benefits of exercise to others.

“Exercise definitely works. It gets you to care about yourself in a very organic way,” he says. “It helps with depression and allows you to get control of your life.”