The 'Interval Training' technique (or High-Intensity Training [HIT]) has gained in popularity as one of the most effective fat burning forms of exercises. Not only is it very effective for this fat loss capability but it also can dramitically improve your cardiovascular capabilities. The theory behind interval training is as follows:
'By mixing bursts of high intensity work with low intensity periods of recovery, you're overloading both the aerobic and anaerobic systems at the same time, getting the benefits of both aspects of training simultaneously' (Appleby, M, 2004)
Without doubt it is more physically demanding than lower-intensity training, but putting this extra effort in can allow you to reap the benefits quicker and more effectively.
How to do it! Aerobic Interval Training
There are an infinite number of exercises that can be done but the general aim is to include short-high bursts of exercise followed by a slightly longer 'recovery' periods. Let's say you chose to use the running machine in your gym. The duration of HIT will vary on your level of fitness but I suggest to start of relatively light for the first week and then to increase either the duration or the intensity as your fitness and stamina develops. A good starting point is to try 6 repetitions of the following intervals.
Interval 1: High-Intensity (1 minute)
Interval 2: Low-Intensity (2 minutes)
Begin with your normal 5-10 minute warm up and then increase the pace to a high sprint (let's say 11 mph) for a 1 minute burst. Some running machines have Interval Training Programs pre-installed but if not you will have to manually alter the speed after each interval. Once the first minute is up, reduce the speed by half and continue with this for 2 minutes. Repeat this cycle 6 times (or more if you can handle it)
During the high intensity periods, you're decreasing your body's ability to exchange oxygen and carbon dioxide. You begin to feel the "burn" as your body eliminates lactic acid (a toxic by-product) and your muscles begin to lose their ability to contract. You wouldn't physically be able to maintain this level of intensity for long. The key point is not to slow down too much on your 'recovery' period as the pulse rate will dip and reduce the aerobic effect. The recovery period will allow your body to adjust and seems like a very pleasant break! But don't get too comfortable - make sure you complete the course
Why is Interval Training Good?
1. It is less time-consuming: You can work yourself just as hard in 30 minutes doing HIT than doing 1 hour or normal low-intensity training
2. It will even help you build up your endurance faster than long-duration cardio!
3. It burns more calories than low intensity training, meaning you can burn more fat in shorter workouts.
4. Higher intensities stimulate your metabolism far more AFTER the workouts than lower intensity training. This means you continue to burn calories and fat for long periods after you're done training
5. It combats monotony
By challenging both your aerobic and anaerobic systems simultaneously you're improving the calorie-burning abilities of your body. HIT can also be highly beneficial for adding new muscle which in turn will help speed up your metabolism. Remember, the more muscle you have, the more calories you'll burn (even doing nothing!)
Try this interval training for a couple of weeks and see what you think. You'll become a fat-burning machine!