A better mood may be a mere 30 minutes away.

Research shows that regular exercise helps alleviate depression and improve well-being over the long term. Now a new study suggests that the mood-enhancing benefits of physical activity may be apparent after a single 30-minute workout. The next time you feel down, grab your gym shoes and give yourself the gift of a 30-minute power walk.

In a recent study, a single 30-minute treadmill workout done at moderate intensity eased depression and increased energy levels. In the study, participants were randomly divided into two groups. People in one group were asked to walk on a treadmill for 30 minutes, exercising at 60 to 70 percent of their maximum heart rate, as determined by age. The other group rested for a period of 30 minutes. Both groups reported relief from depressive symptoms afterward, including a reduction in confusion, anger, distress, and fatigue. However, those who exercised reported significant improvement in their sense of well-being, a benefit not expressed by participants assigned to 30 minutes of rest. Although many kinds of depression may respond to exercise, severe depression may require professional intervention in the form of counseling, medication, or both. If you're feeling depressed, see your healthcare provider for an evaluation.

Effects of acute exercise on mood and well-being in patients with major depressive disorder. Bartholomew, J. B., Morrison, D., Ciccolo, J. T., Medicine and Science in Sports and Exercise 2005 Dec;37(12):2032-2037.