Everyone trying to lose weight wants to know how to maximize their calories burned through working out, and for a long time, the most widely accepted method was low intensity cardio. Whether in the form of running, swimming, cycling, aerobics or elliptical, the standard way of losing weight was by low intensity workout, preferably for a period of over 45 minutes, since that is when the real fat burning starts. However, recently these views have shifted and many people are changing their calorie burning workouts from the classic low intensity workout, to interval training.

Interval training, which is often referred to as HIIT (High Intensity Interval Training), is a form of workout in which you alternate between high intensity and low intensity intervals. During the high intensity interval you operate at 85 to 90% of your peak capacity. The low intervals are mostly designed to replenish oxygen, to allow you to do another high intensity interval. The high intensity intervals usually last from 20 seconds to 3 minutes, and the ratio between the time spent at high intensity to low intensity usually is somewhere between 1:1 to 1:2. Since this type of workout is pretty strenuous and tiring, total workout times usually lie between 15 and 45 minutes.

Here are the different ways in which interval training helps you burn calories:

Interval training allows you to work out at a high intensity for a reasonably long time. If we take walking and running as an example, it's easy to see that by alternately walking and running or sprinting, you will burn more calories than by just walking alone, and you will be able to go on for a longer period of time than if you just sprinted. Interval training burns more calories per time unit than classic cardio does.

By working out at a high intensity, your body produces a lot of a chemical called catecholamine. This triggers fat burning processes in your body. This causes a heightened metabolic rate up to 48 hours after the actual workout. This allows you to burn as much total calories in 24 to 48 hours with a 30 minute HIIT workout as you would with about an hour of low intensity cardio.

High intensity interval training has been shown to preserve and build more muscle mass than longer endurance type workouts do. By increasing your muscle mass, you will burn more calories regardless of whether you're working out or not. Even in rest, muscle burns calories, albeit a small amount.

During the low intensity intervals, your aerobic system is working hard to overcome the oxygen debt which resulted in lactic acid building up during the high intensity interval. HIIT trains both your anaerobic and aerobic systems, which in turn leads to an improved cardiovascular system and lactose tolerance.

Interval training reduces the risk of injuries caused by repetitive stress, as seen in endurance low intensity workouts. For example, when alternately walking and sprinting, the stress on your body is much less repetitive as in endurance training, where you jog for a long period of time.