Originally from : http://jjvirgin.com/3982/effective-efficient-exercise-4-minutes-day/
“The science behind burst training is based on something called the ‘excess post-exercise oxygen consumption’ (EPOC) effect, which is the recovery of one’s metabolic rate back to pre-exercise levels,” says Certified Strength and Conditioning Specialist Jini Cicero. “It is a measure of how much oxygen the body utilizes in the period immediately following a workout or bout of exercise. EPOC directly effects fat oxidation in response to high-intensity exercise.”
In other words, when you burst, your body creates an oxygen debt that it must then repay. This recovery requires energy, which your body utilizes via fat oxidation. Literally, you’re burning fat to meet this demand.
Burst training also increases lactic acid which in turn increases growth hormone. When growth hormone is elevated, fat burning and muscle development is enhanced. Also growth hormone helps to control cortisol levels. When we exercise, cortisol levels rise. In aerobic exercise, cortisol degrades muscle which contributes to slow metabolism and inability to lose weight. In anaerobic exercise such as burst training, growth hormone helps to curb elevated cortisol which then helps to prevent muscle loss