High Intensity Interval Training involves alternating between very intense bouts of exercise and low intensity exercise. For example: sprinting for 30 seconds, then walking for 60 seconds is high intensity interval training. HIIT can be used both anaerobically (in the gym with weights) and aerobically with cardio.
Why Is HIIT The Best Way To Burn Fat?
Exercise physiologists used to believe that “steady state” cardio was superior for fat loss because relatively more fat is used by the body as fuel at lower exercise intensities than at higher intensities.
Yes, you burn more fat relative to glycogen when going for a walk, but what we care about is total fat burn. At higher intensities, you are burning far more fat, even though the fat/glycogen ratio is lower. In addition, interval training allows you to exercise at very high intensities for a much longer period of time than steady state, so you burn more fat.
As an added bonus, there’s also an after-bun effect known as EPOC (excess-post exercise oxygen consumption). You increase your metabolism and burn more calories for up to 24 hours after interval training, whereas going for a jog burns almost NO calories after.