Exercising doesn’t have to be a long, painful ordeal. In fact, if you want to lose weight quickly, research says the best you can do is take part in short high-intensity workouts. That’s because intense exercise depletes the oxygen available to the muscles, forcing them to burn fat for energy instead. On top of that, intense exercise makes the body burn calories for hours after the workout ends in order to make up for the resulting oxygen debt. If you’re not sure which exercises fall under the category of high-intensity, no worries: have a look here to see the common ways people get their dosage of high-intensity workouts.