The key to fat burning is using interval workouts

"Getting Up to Speed

They say that slow and steady wins the race. But the cardiovascular key to fat burning is using interval workouts - workouts that alternate high-intensity levels with lower-intensity effort. As I mentioned earlier, that formula keeps your body burning calories long after you've stopped working out.

Interval workouts mimic sports - start-and-stop motions with periods of sprinting or close-to-sprinting speeds followed by light jogging or rest. You can use interval workouts any way you want - running, cycling, swimming, on elliptical trainers, even walking if you alternate a speed walk and slow walk.

You can also vary the intensity levels in different combinations. To start, here are three options for setting your workout. (If you use exercise machines, don't choose the interval workout; choose the manual one, and create your own intensities by adjusting it yourself. It'll give you greater control over the speeds and will help you burn fat faster.) You'll derive benefits in as little as a 20-minute interval workout. As you build up endurance and strength, you can add time to your workout.

Interval Variation I: Standard

The following is a typical interval workout. You alternate the same period of low intensity with the same period of higher intensity.

1. 3 - 5 minutes warmup (light jog, low intensity, gradually increasing at the end of the warmup period)
2. 1 minute moderate or high intensity followed by 1 minute low intensity (repeat 6 - 8 times)
3. 3 - 5 minutes cooldown (light jog, low intensity, gradually decreasing by the end of the cooldown period)

Interval Variation II: Pyramid

This pyramid structure allows you to start with short bursts of speed, and then you'll peak at the longest surge of energy in the middle of your workout before coming back down.

1. 3 - 5 minutes warmup
2. 30 seconds high intensity, 1 minute low intensity
3. 45 seconds high intensity, 1 minute low intensity
4. 60 seconds high intensity, 1 minute low intensity
5. 90 seconds high intensity, 1 minute low intensity
6. 60 seconds high intensity, 1 minute low intensity
7. 45 seconds high intensity, 1 minute low intensity
8. 30 seconds high intensity
9. 3-5 minutes cooldown

Interval Variation III: Sports Conditioning

Sports are unpredictable. This interval simulates some of that unpredictability by having you doing different times and different intensities. You can mix and match the orders and repetitions as much as you want. Rest longer after the periods in which you use the most energy.

1. 3 - 5 minutes warmup
2. 2 minutes moderate or high intensity followed by 2 minutes low intensity (repeat once
3. 30 seconds high intensity followed by 30 seconds low intensity (repeat four times)
4. 60-yard sprints (or 10 seconds if not running) followed by 90 seconds rest (repeat 6 - 10 times)
5. 3 - 5 minutes cooldown"

This article has a few interesting HIIT cardio routines. Give them a try.

I will continue posting on this subject because my feeling is today's athletes still don't know enough about HIIT and don't realize all the advantages it has for fat loss, cardiovascular and physical conditioning. Reed more about it here.