HiiT stands for High Intensity Interval training and is hands down one of the best ways to burn fat without causing your body to catabolize your own muscle tissue.

The HiiT workout dvd features three different high intensity routines that are all right around 30 minutes or less making these workouts perfect for you to use on days where you're short on time.

The first HiiT workout is 30/30, and as the title suggests, each interval is divided into 30 second high energy, plyo reps, followed by an equal 30 second rest for a total of 16 tough intervals.

The 2nd HiiT workout is 40/20 and you'll be doing 16 intervals. Each interval will be divided into 40 second high energy, plyo reps, followed by a 20 second rest. Three additional one minute breaks will be spread throughout the program.

The 3rd HiiT workout is Double Wave Pyramid. In this workout you’ll do two rounds of intervals separated by only a one minute rest. In each round, you'll follow a pyramid cycle of nine intervals, in which you'll start your first set with a 20 second interval, and work your way up to the top of the pyramid, increasing each interval by five seconds as you go. Then you'll work your way back down the pyramid decreasing each interval by five seconds.

• Only a step is needed for the first two workouts. No equipment is needed for the third HiiT workout.