Life's too short to be stuck doing an exercise you loathe. Try a few different workouts until you find one that suits your personality. If you hate waking up at 6 a.m. to run, don't do it! You'll be more apt to stick to a routine once you identify which workouts actually make you look forward to exercising. Not only that, the more you exercise, the more you may be helping your social life — another way to increase happiness.