Scientific evidence has suggested that physical activity can be a great ally in fighting the symptoms of depression.  Depression around 40 million adults in the United States each year, according to the Anxiety and Depression Association of America.

A recently review of the literature looking at the effects of exercise on the risk and symptoms of depression published in Current Sports Medicine Reports — concludes that exercise is indeed an effective “medicine” against depression in most cases.  The authors also found that many programs dedicated to treating depression do not include exercise in their list of recommendations for the prevention and treatment of the condition.

In their review, the researchers combined the results of 49 studies that evaluated a total of 266,939 participants between them.  The analysis revealed that across all groups, exercise could help reduce depression risk by 17%.

The researchers also looked at the data to determine if there were any differences across different countries and ages.  According to these analyses, the protective effects of exercise were significant across all ages.  For example, children and adolescents with higher exercise levels had a 10% decreased odds of depression, adults 12% decreased odds and older adults 21% decreased odds.  All the countries for which studies were found also demonstrated benefit across nationalities: Asians demonstrated a 24% decreased odds of depression, Europe 17% decreased odds, North America 14% decreased odds, and Oceania 35% decreased odds.  Moreover, those people completing the minimum of 150 minutes of moderate to vigorous physical activity per week decreased their odds of depression by about 22%.

Conclusuions

The researchers acknowledge that physical activity may not be equally effective for everyone. They point out that future research should strive to better understand who, exactly, is most likely to benefit the most from physical activity in the context of mental health.

As to why exercise seems to have such a significant antidepressant effect in most cases, the authors point to research that suggests physical activity’s positive effect on mental health may be because exercise can help reduce inflammation, protect cellular health, and help brain cells regenerate.  However, more research needs to be conducted to confirm these thoughts.

Physical activity can confer protection from the development of depression in children, adults, and older adults. These effects are evident in all continents studied.  Also, among people with depression, exercise can be used for acutely managing symptoms.