Want to get the most out of your workouts? Try interval training! This simply means alternating bursts of intense activity with intervals of lighter activity. Take walking. If you're in good shape, try incorporating short bursts of jogging into your regular power walks. If you're less fit, alternate leisurely walking with periods of faster walking. (For example, if you typically walk outdoors, walk faster between certain mailboxes, trees or city blocks.) The more vigorously you exercise, the more calories you'll burn, even if you increase intensity for just a few minutes at a time.