HIIT (High-Intensity Interval Training) is a training technique in which you input 100% of your energy focussing on quick, intense bursts of exercise, followed by short, sometimes active, recovery periods. This type of training gets, and keeps, your heart rate up and burns more fat in less time.
A High-Intensity workout increases the body’s need for oxygen during the training and creates an oxygen shortage. This causes your body to ask for more oxygen during the recovery period. This afterburn effect is referred to as Excess Post-Exercise Oxygen Consumption (EPOC) and is the reason why intense exercise will help burn more fat and calories than regular aerobic and steady-state workouts.
HIIT will help you to burn calories at the rate up to 1000 kcal/hour.