The scientific evidence that exercise can play a significant role in alleviating depression, anxiety and mood disorders has been mounting. As neuroscientist Carl W. Cotman of the University of California at Irvine has observed, "Individuals who are appropriately physically active may be able to protect themselves from depression -- or be less depressed or relieved from depression -- if they are physically active."
Antidepressant Effects
In a March 2010 presentation to the annual conference of the Anxiety Disorders Association of America, psychologists Jasper A. Smits and Michael W. Otto urged mental health care providers to incorporate exercise therapy into their treatment programs for depressed patients. Smits and Otto, coauthors of "Exercise for Mood and Anxiety Disorders," analyzed a wide range of published studies and clinical trials, concluding that exercise affects the brain's neurotransmitter systems in ways similar to antidepressant medications. For various reasons, many depressed people lack access to treatment but a "public health dose" consisting of 150 minutes a week of moderate to intense exercise, or 75 minutes a week of vigorous to intense exercise, can result in an immediate easing of symptoms."Therapists can help their patients take specific, achievable steps," Smits said. "This isn't about working out five times a week for the next year. It's about exercising for 20 or 30 minutes and feeling better today."
Brain Structure
Exercise is suspected to change brain chemistry by triggering the release of "feel-good" chemicals, but a multidisciplinary study led by the University of Pittsburgh has shown that it may also change the structure of the brain itself. The study, published in April 2010 issue of the journal "Neuroscience," examined the brain tissue of monkeys following a five-month exercise program and found that the number of blood vessels in the motor cortex region of active animals had increased, while blood flow in the brains of sedentary animals stayed the same. The physically active monkeys also showed improved cognitive function. After three months of inactivity, though, benefits disappeared.
Brain Chemical
Neuroscientist Carl W. Cotman of the University of California at Irvine led a study, published in the May 2010 edition of "Neuroscience," investigating how exercise influences levels of brain-derived neurotrophic factor, or BDNF, in rats. This natural chemical, known to have antidepressant properties, is depleted in people suffering from major depression. Among animals with unrestricted access to running wheels, increased levels of BDNF, along with improvements in the performance of a task used to assess levels of depression, were noted. In addition, decreased levels of a plaque associated with Alzheimer's disease was found in elderly but active animals. Other results included "significant" enhancements in memory and learning ability that lasted for more than a week after exercise ceased.
Exercise plus Antidepressants
A study conducted by Southwestern Medical Center in Dallas and published in the July 2006 "Journal of Psychiatric Practice" examined the effects of regular exercise on 17 patients taking medications for major depression. Over 12 weeks, significant reductions in the severity of symptoms were charted, leading researchers to conclude that preliminary evidence suggested that a combination of exercise and antidepressants might prove to be a more effective treatment than medication alone.
References
- Mayo Clinic: Depression and Anxiety: Exercise Eases Symptoms
- Science Daily: Science News, April 10, 2010: Mental Health Providers Should Prescribe Exercise More Often
- Time Magazine: Is Exercise the Best Drug for Depression? June 19, 2010
- Centre for Neuro Skills: Special Report: Exercise Has a More Powerful Impact on the Brain than Previously Thought
- University of Pittsburgh School of Medicine: Regular Aerobic Exercise is Good for the Brain, Pitt Team Says
- PubMed: Exercise as Augmentation Strategy for Treatment of Major Depression, Abstract, July 12, 2006 article
