Researchers now think that exercise triggers the release of "feel good" endorphins in the brain, one of which, enkephalin, is believed to prevent the release of excessively high levels of adrenaline and cortisol. A session of exercise also triggers the stress response—a plus for those who are underchallenged. If you're having either a stressful or a low-energy day, head for the gym or squeeze in a 20-minute ultrabrisk walk, recommends Mark Hamer, an exercise physiologist at University College in London. You'll get the biggest benefits within an hour after you work out.
Any treat that activates your brain's pleasure centers—a massage, a piece of rich chocolate, a funny movie—can similarly dampen your stress levels. Novelty is what you're shooting for if your stress levels are too low: Head to an amusement park, sign up for a challenging art class, or take a rafting trip down some rapids. With practice, you can get good at avoiding that "most useless place...for people just waiting...for a better break...another chance," in the words of Dr. Seuss in Oh, the Places You'll Go! His advice: "When things start to happen, don't worry. Don't stew. Just go right along. You'll start happening too."