Running is said to be perfect therapy for stress reduction! When you run, your body increases the release of serotonin in the brain. Running on a regular basis steadily raises the level of tryptophan (an amino acid used to manufacture serotonin). This is great news because Serotonin is responsible for mood balance, sleep, memory, and social behavior. A deficit of serotonin in the brain can influence depression and anxiety. Although other exercises such as yoga, weight training, and Pilates are good for producing serotonin, aerobic exercises like running or swimming have been shown to be the most effective.