What is HIIT Exercise?

HIIT is fast and furious sign

HIIT is the abbreviation used for High Intensity Interval Training.

You may also see this form of exercise called HIIE (high intensity intermittent exercise) or SIT (sprint interval training) and are all alluding to the same form of exercise.

HIIT is a cardiovascular exercise that alternates between short periods of high intensity exercise followed by short rest periods of less ferocity until you are exhausted and can not go on.

There is no “industry wide” set times for either the high intensity, rest periods, or entire workouts. However, the entire HIIT training session typically last less than 30 minutes. 

HIIT type exercises are proven to significantly reduce fat for people willing to use it regularly.

HIIT vs Steady State Cardio

This high intensity type of exercise, workout, or training session has taken the fitness industry by storm over the past decade — and for good cause.

Most fitness and health professionals have believed that the secret to fat loss (when it comes to exercise) is long sessions of steady state cardio.

Steady state means that trainers were advising people to run or jog on the treadmill or outside for 45 minutes to an hour.  The theory is that the more time you spend in this steady state of cardio exercise, the more calories you would burn. 

And that is definitely true — to a point.

However, more modern and extensive research and testing has shown:

HIIT is a More Natural Way to Exercise

If you stop and think about it for yourself, you will realize that no animal in the wild runs for an hour continuously. And besides that, if you watch children at play, you will always see short burst of running or vigorous activity; not 45 minutes to an hour of running hard.

It’s much more natural to see short and extremely fast burst, immediately followed by rest.

When a lion chases its prey — it explodes into action for less than a minute. If it can’t catch the prey, it stops.

The same applies to any other predator.

Man is the only animal that runs marathons and subjects himself to long sessions of cardio and later wonders why his joints are giving out.

Why HIIT Works

Like I said earlier, there’s been quite a bit of scientific research into HIIT training — and the reasons High Intensity Interval Training works so well for weight loss is proven.

Scientist, researchers, and trainers have discovered that short, very intense sessions of training yields far better results than longer sessions of steady state cardio.

Here’s what makes HIIT is so powerful:


The answer is EPOC. Oh great! Another acronym.

EPOC stands for excess post-exercise oxygen consumption.

What this means is that when you engage in a HIIT session, your body experiences an ‘oxygen deficit’.

You might compare the calorie burn of HIIT to taking a huge loan from the bank. It’s going to take you a long time to repay that loan.

When you exercise for very short and very high intensity sessions you are using all available oxygen as you are panting and gasping for more air. 

Long after you are through with your HIIT training for the day, your body now stays in a fat burning mode.

Your body is now repaying the oxygen deficit from when you were having to gasp for more air. 

Here’s what most people don’t understand:

You don’t burn as many calories DURING a HIIT SESSION as you would if you were to jog for 45 minutes.

For example, if you jogged for 45 minutes, you may burn anywhere from 370 to 450 calories, depending on your weight and age.

The same person who does a HIIT session may burn only 180 calories within the 15 minutes of training.


Since his body is in calorie burning mode for 12 to 16 hours after the workout is over, he will burn far more than 450 calories overall.

Remember the bank loan comparison? Due to the fact that the high intensity pushed you to your maximum oxygen use for your training session, your body now stays hard at work for hours recovering and burning calories.

This is what makes HIIT so potent.

The fat burning benefits of jogging and steady state cardio on the best cardio equipment only last during the workout session and quickly tapers off after.

With HIIT, you’re a fat burning machine round the clock. This is the reason why people who do HIIT see much faster weight loss results.

2. Increases Stamina

HIIT improves your stamina greatly.

You’d think that the long cardio sessions would do a better job of this… but they don’t.

HIIT sessions force your body into a state of discomfort. Stamina is always increased by regular periods of discomfort and exertion above the normal.

You’re constantly operating at your VO2 max. (VO2 max is in general terms operating at your personal maximum oxygen intake levels).This state will greatly improve your endurance.

3. Helps build lean muscle

While HIIT will not make you gain as much muscle as weight training that’s focused on hypertrophy, it does help to build lean muscle because of the full body workouts.

So, you can burn fat and build some lean muscle.

4. Taps into stubborn fat stores

HIIT will force your body to burn the stubborn belly fat that it loves clinging on to.

The body has no choice but to burn fuel because of its energy needs…

And HIIT demands a lot of energy.


HIIT is NOT an easy style of training.

It is hard, tiring and most people will dread it.

That’s the way it is.

But, this style of exercise only last for a few minutes,

And the results are phenomenal!

You’re going to be in the ‘pain box’ for 8 to 15 minutes, depending on how long your training sessions last.

However, once you’re done, your body will be burning fat for hours after that.

You’ll end up losing more fat, start looking leaner and feeling much better.

HIIT is definitely something you should include in your training regimen whether you’re just exercising for fitness, or using workouts for losing weight.

And the thing about hit is that it works in any exercise you incorporate it in.

Try HIIT on one of my favorite home cardio machines and change your body fast!

If you are a walker, you can walk as fast as you can until you must stop for air. Now walk at your regular pace just until you can stop gasping, and go full throttle again.

What HIIT does is to simply cause you to reach for much more oxygen use than normal for very short and intense periods. Try it yourself, you will love the results.

Leave a Comment