How To Do High Intensity Interval Training

Imagine a workout in which you burn a lot of calories and when you’re done somehow your body keeps burning more calories for hours and hours – and maybe even continues burning into the next day! Now, what if you could achieve that bonus calorie-burning effect in less than half the time of your normal workout?

Although this promise of enhanced calorie burning may seem like something you’d see in a fancy made-for-TV exercise contraption or expensive magic pill advertisement, it is actually based on a simple and well-researched concept called High Intensity Interval Training, or HIIT.

What Is High Intensity Interval Training?

The concept of High Intensity Interval Training is fairly simple. To do HIIT, you warm-up, and then you do an intense burst of cardio, followed by a full recovery period.

For example, a HIIT workout on a bicycle might involve getting on a bicycle, warming up for 5 minutes, and then performing 6 to 8 30-second efforts as hard as you can possibly go, followed by a very easy 90 seconds of pedaling between each 30-second effort. Once you’ve completed each of the hard efforts, you’re done!

With a routine such as the one just described, you can burn just as many calories as an easy one-hour bike ride, stimulate more muscle, get fitter faster, and still have time to go shopping for new clothes to fit your shrinking waistline.

How High Intensity Interval Training Works

When you exercise, your body uses oxygen to create energy. But when you reach a high intensity during exercise, your body’s demand for oxygen exceeds your ability to breathe in that much oxygen and deliver it to the muscles. When this happens, your body goes into an “oxygen debt.” Once you go into oxygen debt, not only do your muscles begin to burn and you begin to breathe hard, but you also put your body into a state where it needs to “repay” that oxygen debt after exercise.

While repaying a debt may seem like a complex topic better addressed by the Money Girl, it is actually quite easy for your body to repay oxygen debt. You simply need to breathe more and breathe deeper. And when you breathe more and breathe deeper, your body burns more calories. Depending on how hard you’ve worked, this oxygen repaying can help you burn anywhere from a few dozen to over a hundred extra calories each hour after you exercise, for up to 24 hours after you’ve finished!

Of course, this is where high intensity interval training comes in. Besides weight training, one of the best ways to create high post-exercise oxygen consumption is via the hard cardio efforts you’ll do during a HIIT routine. While it would be virtually impossible to create that oxygen debt by riding a bicycle as hard as you can for 10 minutes, you can easily split those 10 minutes into several 30-60 second efforts followed by long recovery periods, and still achieve the same calorie burning effect!

How To Do High Intensity Interval Training

While there are no special rules for performing a HIIT routine, here are 5 Quick & Dirty Tips to get you started with your interval training:

1. Limit interval length to 2 minutes – If you’re doing one of your hard intervals and you can go longer than 2 minutes, then you probably aren’t exercising hard enough to generate a significant post-exercise calorie burning effect.

2. Go at least as long as 10 seconds – You can do efforts as short as 10 seconds, but remember: the shorter your intervals, the more sets you’ll need to do. For example, one HIIT routine I teach in a spin class includes 10 repeats of 10 seconds of hard pedaling with 20-second rests, then 8 repeats of 20 seconds with 40-second rests, and finally, 6 repeats of 30 seconds with 60-second rests.

3. Beat boredom – You can mix things up during your HIIT routine. For example, do 3 hard efforts on the bike, then go over to the treadmill for 3 more, then move on to the elliptical trainer or rowing machines.

4. Combine with weight training – In Which Workout Burns the Most Fat?, I outline a fat-burning routine that includes a weight lifting circuit combined with hard cardio efforts at the end of each weight training exercise. This can be as simple as hitting the gym with a jump rope and jumping as hard as you can for 30 seconds after each weight training set. If you’re like me and look like a spastic Bambi on ice while jumping rope, then just do jumping jacks instead.

5. Recover – Remember, the purpose of HIIT is to allow you to go very hard during your intense intervals, and you won’t be able to do that if you don’t fully recover before each! I recommend at least a 1:2 interval to rest ratio, and up to a 1:4 interval to rest ratio. For example, a 1:2 interval to rest ratio would involve hard 60-second efforts followed by easy 2-minute recovery periods. And I’m certain the Math Dude would be proud of our efforts to use ratios.

Now that you know how to do high intensity interval training, it’s time to hit the gym!

If you have a favorite HIIT routine you’ve found, share it with us in Comments or on the Get-Fit Guy Facebook page! I’d love to see the interval routines you’ve done, and help you make your HIIT even more effective!

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