Researchers began the study by showing 80 men and women an upsetting scene from the film The Champ before asking them to fill out a questionnaire about their emotional state. Then, half the group went for a 30-minute jog while the other half stretched for the same amount of time. Finally, after completing their assigned activities, the participants filled out the questionnaires again.
In the end, the people who ran reported less sadness than those who stretched, and, beyond that, the people who described their pre-workout emotional state as "despair" saw a greater improvement if they ran.
The researchers admitted that there's still a lot we don't know about how or why aerobic exercise actually affects our mood. With something as subjective as what makes people happy, it's difficult to say if any one thing will always work. But these findings suggest it wouldn't hurt to give a run a try next time you're feeling super sad. At the very least, this is good info if you have to get through watching this scene from Good Will Hunting. Dry those tears; then, lace up your running shoes.