If there’s one thing we learned from watching Reese Witherspoon in Legally Blonde, it’s that exercising releases endorphins and endorphins make you happy. Now, a study featured on Science Daily takes a closer look at this phenomenon by putting physical activity up against depression.

Researchers analyzed 39 trials involving 2,326 individuals diagnosed with depression. 35 trials revealed that exercise had moderate effects on depression, which proved to be as effective as anti-depressants, but without the side effects.

Although the results are promising, more research is needed. "Our review suggested that exercise might have a moderate effect on depression. We can't tell from currently available evidence which kinds of exercise regimes are most effective or whether the benefits continue after a patient stops their exercise programme," study author Gillian Mead reports.

In spite of this, researchers still recommend regular exercise, especially during times of stress and sadness.

(Photo by lululemon athletica via Flickr Creative Commons)