With exercise, there aren't really any shortcuts—but there are shorter workouts. Take high-intensity interval training, or HITT, for example. These workouts are challenging but get the work done in less time by alternating short bursts of high-intensity moves with rest periods. Research suggests they can burn fat more effectively than longer workouts at a less intense pace. And you don't even have to go to the gym! Try this 10-minute HITT workout that can be done anywhere, at any time.