How Interval Training burns more fat than slow, less intense aerobic exercise
Interval training allows you to exercise at higher levels of intensity compared to continuous aerobic exercise. When you alternate between short bouts of very high-intensity exercise with lower-intensity exercise, your body is able to process lactic acid build-up, therefore reducing fatigue. You are then able to burn calories and fat at a faster rate compared to less intense, longer aerobic exercise.
Post-Exercise Calorie and Oxygen Consumption
At rest, your body needs oxygen and calories from carbohydrates, fat and protein to maintain life. You need more calories and oxygen to perform exercise, especially at high intensities. Once you stop exercising, your body still requires calories and oxygen as it works to bring you back to resting levels. Your body uses more calories and oxygen after high-intensity interval training than after steady-state aerobic exercise to return to a resting state. In simple terms, your metabolism will function at a higher rate and for a longer period of time after an interval workout versus an aerobic workout of the same duration.