High intensity interval training, or HIIT training, is exercise comprised of alternating short periods of very vigorous activity and longer periods of active recovery time. The vigorous intervals are brief, but challenging. For example, if you applied HIIT principles to running, you would (after a warm-up) sprint as hard as you could for two minutes, then jog for 5 minutes, then sprint again for 2 minutes, and so on. This approach allows for maximum fitness gains and fat-burning in a workout of short duration. High intensity interval training is not for new or beginning exercisers; you need to have a basic level of cardiorespiratory fitness first.
High intensity interval training can be done on a cardio machine such as an elliptical, stepper, or stationary bike, or outside while you run, walk, or bicycle.
See a sample HIIT workout.
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