Researchers have a new explanation for why exercise reduces depression. A study published in July suggests that exercises may exert anti-depressive effects by reducing brain inflammation and cultivating motivation.
Study lead author Emily Hird, a research fellow at University College London with a doctorate in cognitive neuroscience, said the positive effect of aerobic exercise has been demonstrated through randomized trials. Still, the specific biological and psychological processes are not well understood.
“We are proposing that exercise—particularly aerobic activities that make you sweaty and out of breath—decreases inflammation and boosts dopamine transmission, which in turn increases the desire to exert effort, and therefore boosts motivation generally,” Hird said in a statement.
Inflammation is known to inhibit the transmission of dopamine, a neurotransmitter believed to influence decisions leading to pleasurable rewards, according to the study, published in Translational Psychiatry.
Exercise Lifts Spirits
Dopamine, which transmits messages between nerve cells in the brain and throughout the body, is associated with experiencing pleasure, as well as motivating us to seek rewards. Therefore, some antidepressants aim to reduce depressive symptoms by boosting the neurotransmitter’s release. However, most antidepressants relying on this principle have “limited success,” likely because they rely on an ineffective “one-size-fits-all” approach to treating depression, the study authors wrote.
“Several studies indicate that dopamine transmission is enhanced by physical activity, in particular aerobic exercise, indicating this as a potentially useful alternative method to boost dopamine and increase motivation in depression,” they wrote.
The researchers said in the study that exercise is well-suited to early intervention for depression because of its low cost. It may also have beneficial effects on physical health conditions potentially linked to depression, such as obesity. Exercise also improves self-esteem and reduces stress.
Dr. Karl Benzio, a psychiatrist and medical director of a Florida residential treatment center who was not involved in the study, said exercise can be a key component of the treatment plan for mild and some moderate depression.
Benzio also affirmed that exercise releases dopamine and adrenaline, chemicals that provide uplifting feelings. Exercise dramatically improves blood circulation to the brain, supplying it with oxygen and vital nutrients. It also carries away waste products, detoxifying the brain.
“Exercise also gets us away from the stressors and removes us to a place where we can be in the present and away from everything that is weighing on us,” he said. “Even getting out and walking for 30 minutes can help.”
The University College London researchers expressed a need for large, randomized controlled trials to unravel the physiological explanations for exercise’s antidepressant effect.
“Understanding the mechanisms underlying the antidepressant effects of physical activity in depression could inform understanding of the mechanisms causing depression as well as the development of novel intervention strategies, in particular personalised intervention and social prescribing,” they wrote.
Exercise Isn’t the Only Thing Needed
Benzio said that exercise is a valuable part of who we are and can help us overcome depression. Other essential elements for fighting depression include diet, decision-making, and working on skills. He said he also prescribes medication and psychotherapy at his clinic.
“We need to address all three spheres: spirit, mind, and body,” Benzio said. “When you address the physical through exercise, it starts to give some motivation, to help stimulate and heal the brain, so the patient can think more clearly.
“Depression is very complicated, and there are a lot of reasons a person is depressed. If it’s a significant depression, then exercise is not going to be the only remedial aspect,” he said in an interview with The Epoch Times. “With the psychiatric reasons for depression, I believe there are biological elements. The way exercise is beneficial is through a release of endorphins, releasing those chemicals that give us a sense of euphoria, that runner’s high that people get.”