Physical activity is one of the best methods for fighting stress. Exercise helps you feel better by harnessing the body's natural fight or flight response, rather than suppressing it. Exercising for twenty minutes or more can enhance mood by releasing chemicals we've previously discussed called endorphins which relieve pain and increase a sense of well-being and relaxation. Exercise also helps relieve tension caused by muscle contraction. Exercise burns the energy that has been stored in the muscles, allowing them to return to their normal resting state after exercise is complete.