If you're new to high intensity interval training (HIIT), this post will give you all the information you need on how and why these workouts work. Plus, there's a nifty infographic for you to download if you like.

What is HIIT

HIIT combines high intensity training with interval training, both of which are very effective at burning fat. So, what is high intensity and interval training? High intensity training is training where you are at your maximal output for the workout. It causes your muscles to work at thier maximum capacity, and in turn to use more oxygen. Interval training is training that alternates between higher intensity training and lower intensity training within the same workout. It boosts your metabolism during and after your workout and is more effective at building lean muscle than steady state workouts.

How a HIIT workout works

When you see a HIIT workout, it will usually list rounds, intervals, and exercises, something to the effect of:

• 12 rounds
• 45 seconds work
• 15 seconds rest

1. Squat
2. Push ups
3. High Knees
4. Crunches

What this means is that you will set your interval timer (either your Gymboss timer, or an app on your phone) to 8 rounds with intervals of 45 and 15 seconds. I like to have the rest interval as the first one so that I have time to get ready once I push the start button. Once you hit start, you will wait for the rest interval to be over and the timer will beep for your work round (the 45 seconds). When the work interval starts, you will do as many squats as you can in 45 seconds then rest for 15 seconds. When the second round starts you will do as many push ups as you can in 45 seconds then rest 15 seconds. Continue until you have gone through all 4 exercises. Since the timer is set for 12 rounds, you will go through all 4 exercises 3 times for the complete workout.

Three HIIT Protocols

Now that you know what HIIT is, you might like to know that there are three different "official" HIIT protocols. The first is the Tabata protocol developed by Dr. Izumi Tabata. According to Tabata, maximum workout efficiency can be acheived by completing 8 rounds of 20 seconds rest and 10 seconds work two to four times a week. Next is the Little method developed by Dr. Jonathan Little and Martin Gibala, The Little method prescribes 12 rounds of 60 seconds work and 75 seconds rest three times per week. Finally, the Turbulence Training method designed by former athlete Craig Ballantyne. Turbulence Training calls for 8 rep weight training sets alternated with 1 or 2 minutes of cardio for up to 45 minutes, three times per week.

  The final thing to note about HIIT workouts is that while you're completing the work round, you should be HIITing it so hard that if you tried to talk, you wouldn't be able to. That's how you get the most out of these workouts and make sure that you'll continue to burn calories for up to 48 hours afterward. :) Pamela