High Intensity Interval Training, or "HIIT," is an exercise philosophy that has been proven to be one of the most efficient exercise methods to get fit, burn fat, and is also one of the best high calorie burning workouts you could possibly do! Basically, when your body moves quickly between high, moderate, and low intensity workouts, it confuses itself into working more efficiently! Benefits of HIIT workouts include a quicker metabolism (you'll burn calories hours after you've finished your workout!), a shorter time at the gym, more efficient fat-burning, AND you don't need any equipment. Sounds good to us! Read on for two incredible, butt-kicking and high calories burning workouts that'll have you feeling and looking like a summer dream in no time.