What’s High-Intensity Interval Training (HIIT)?

HIIT has become the go-to workout protocol when it comes to bodyweight exercise, gaining in popularity every year.

More and more physically active people are getting into this condensed workout method that uses a combination of high-intensity bursts of exercise and short rest times.

Learn all about the many advantages of the HIIT method from the FizzUp trainer or start our Tabata program now!


After Professor Izumi Tabata conducted a study in 1996, HIIT started gaining ground with fitness enthusiasts, professionals and personalities.

In his study on the “effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO₂ max,” he shows that high-intensity exercise is more effective than moderate-intensity exercise when it comes to building cardiovascular endurance and burning fat.

Since then, HIIT has been used to develop a wide variety of workout protocols, but there’s no exact formula or perfect workout. These are the most common protocols:

  • The Tabata protocol: With a workout that lasts four minutes, this is one of the most intense versions of HIIT. The goal is to do 8 cycles in a row, with 20 seconds of max-intensity exercise, followed by 10 seconds of rest time. For maximum effectiveness, Professor Tabata stresses, that if you feel fine after a workout, then you didn’t do it right.
  • The Little protocol: This method uses longer workouts ranging from 18 to 27 minutes. It aims to get you the body of an athlete in minimum time, but you have to do 3 workouts per week. Each workout is made up of 8 to 12 cycles, divided into 60-second periods of high-intensity exercise and 75-second periods of low-intensity exercise.

As you can see, with the HIIT method, your workouts are short and intense. No matter how long your HIIT workout is, you need to remember to warm up before and to let your body have a peaceful return to rest after your workout.


Since the mid-1990s, many studies have been conducted to compare HIIT to moderate-intensity exercise in terms of their effectiveness and health benefits. Many have shown that HIIT can have numerous positive effects on your body.

In 1994, a study by Dr. Tremblay highlighted how HIIT positively influences weight loss in physically active people. According to this study, a workout program using 15-minute high-intensity intervals burned 9 times more fat than a regular 20-minute endurance workout.

In 2012, a study conducted by Australian researchers on the “effect of high-intensity intermittent exercise on body composition of overweight young males” confirmed that HIIT has a positive impact on cardio respiratory endurance (earlier proven by Tabata’s study) and that HIIT workouts boost your body’s basal metabolic rate for several hours after your workout.

When your metabolism works significantly harder, this triggers higher energy consumption, which in turn burns more calories. This reaction is also called EPOC, or excess post-exercise oxygen consumption. The effort your body endures is so intense that it needs to return to its normal state, which consumes even more energy. This goes to show that HIIT is the best workout method for burning excess fat.

Want to give it a shot? FizzUp fitness training includes a variety of effective HIIT protocols in your workout program, designed according to your goal and current fitness level. Download the FizzUp app now and start the Tabata program to feel how powerful HIIT really is!

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