A study of almost 50,000 women over a 14-year period found older women who exercised more and spent less time watching television were the least likely to be diagnosed with depression.

What’s more, the study results published in the American Journal of Epidemiology also revealed women who exercised at least 90 minutes per day were 20 percent less likely to be depressed than those who exercised 10 minutes or less per day.

This could be explained by the endorphins released during exercise, as well as the boost in self-esteem more physically-active women often experience.

While television in and of itself couldn’t be linked to depression, women who spent three hours or more in front of the tube every day were 13 percent more likely to be diagnosed with depression. These results may be due to those women spending their free time watching TV instead of exercising. It’s also possible that they might have been experiencing some symptoms of depression before they were diagnosed, leading them to exercise less.

“[This] adds to the growing body of evidence that physical activity is important to maintain brain health,” said Gillian Mead, who studies geriatric medicine at Edinburgh’s Royal Infirmary.

[Reuters]