Is The Afterburn Effect Real?

Written By: Todd Kuslikis
September 17, 2014

This guest post was written by Dennis Heenan, creator of Anaerobic Threshold Training (AT2).

You hear it everywhere: “It’s all about the afterburn effect.”

Some people claim you can burn up to nine times the fat and experience 48 hours of post-workout fat-burning from one single workout. I’ll hazard a guess that you’ve heard this all before.

If you’re not familiar with the afterburn effect, in short, it refers to the amount of calories that your body is able to burn post-workout.

running on the treadmill

When you hear about these research studies that show you can burn nine times the fat, your first instinct is very likely to be, “Heck yeah! I want to burn that much fat when I’m sitting on my couch after my workouts!”

It sure sounds appealing, but when you dig deeper into these studies, the real truth comes out.

The Truth

I’ve always had mixed feelings about the afterburn effect, simply because it’s been so over-hyped within fitness circles in recent years. In fact it’s been so over-hyped that people often forget about possibly the most important factor in fitness and fat-burning success. More about that later. First, let’s look at the evidence.

treadmillIn 1994, the Journal of Metabolism published the study that found that subjects burned nine times more fat through high-intensity interval training when compared to steady-state, low-intensity cardio workouts.

Now before I reveal the shocking truth that has been hidden within this study for years, let me first say this: I am NOT hating on interval training. Interval training is a great way to burn fat, build muscle, and increase cardiovascular fitness, but it needs to be done the in the right way. More on that in a moment, but first, back to that study.

In the study, researchers took thirteen men and fourteen women and split them into two separate groups:

Knee health score 3
  • Group A performed high-intensity interval training (HIIT) for 15 weeks.
  • Group B performed steady-state cardio for 20 weeks.

After the study, the researchers did indeed find that the body fat percentage of Group A was three times lower than that of Group B. This was even though Group B trained twice as long as Group A.

However, there’s something that most people forget to mention. Over the 15 weeks, the HIIT group lost a whopping 0.2 pounds of fat.

Read that again: 0.2 pounds of fat in 15 weeks.

Wait, what?! When I first read that, I remember thinking, “Well, that makes me want to never do intervals again!”

runningIn comparison, the steady-state cardio group lost one pound of fat during their 20 weeks of training. So could we claim that steady-state cardio produces five times more weight loss than HIIT? In a sense, I guess we could.

The real question, though, is how is it possible that the same study can lead to two completely different conclusions? The study can simultaneously be taken to show that:

  1. HIIT burns up to nine times more fat than steady-state cardio, and
  2. Steady-state cardio results in five times more weight loss than HIIT.

Both statements are relatively true, right?

Listen, I’m telling you all this because you need to be informed about such impressive claims as those that are made about the afterburn effect.

Because of this study, there’s one huge mistake a lot of people make when it comes to their workouts. They focus too much on the afterburn effect, and forget all about the calories burned during the workout.

Why just focus on the afterburn effect when you can focus on the calories burned both during and after the workout? Surely that would yield the best results? Of course it would.

Here’s the good news: it’s quite easy to achieve great fat-burning results both during and after your workout.

Anaerobic Threshold Training (AT2)

After discovering the truth about the above study, I started digging deeper for solutions for how to burn the most fat in the least amount of time. During the study, the steady-state cardio group was training for 30-40 minutes 4-5 times per week. Let’s be honest, “ain’t nobody got time for that!”

During my research I came across a protocol known as Anaerobic Threshold Training (AT2 for short), which focuses on producing more lactic acid during your workout.

According to researchers, when lactic acid is present during a workout, your body is forced to burn off stored sugars and fat for energy. It also forces your body to naturally start producing powerful fat-burning hormones (like growth hormone and testosterone), leading to even more fat-burning.

Here’s the best part: your workouts don’t need to be long. In fact, I’ve found that as little as 11 minutes can do the trick when trying to drastically increase lactic acid during your training.

one arm pushupI’ve found the best way to make all of this happen is through strategic high-intensity strength-based exercises, just like in the workout below.

Odds and Evens

Here’s how it works. Every time the clock hits “:00” you will perform the exercises below, depending on if it’s an odd or even minute. Whatever time you have remaining in that minute is your rest period.

  • Odd minutes – 10 pull-ups, 10 push-ups
  • Even minutes – 10 bodyweight squats, 10 shoulder push-ups

So a workout would look something like this:

  • 00:00 – 10 bodyweight squats, 10 shoulder push-ups
  • 01:00 – 10 pull-ups, 10 push-ups
  • 02:00 – 10 bodyweight squats, 10 shoulder push-ups
  • 03:00 – 10 pull-ups, 10 push-ups

And so on, until the 11-minute timer goes off.

This style of training not only allows you to increase lean, metabolic muscle (leading to more fat loss), it also pushes your anaerobic threshold with each rep, leading to a drastic spike in lactic acid. This is exactly what we want.

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So not only will you be burning a ton of calories during your workouts, you’ll also experience immense post-exercise oxygen consumption (EPOC, or the “afterburn” effect) because of the high intensity of the workout.

Best of both worlds, right?!

Here’s my closing challenge for you today. STOP focusing just on the afterburn effect OR the amount of calories burned during your workout, and instead focus on BOTH!

And that, my friends, is how you should be training. If you want more Anaerobic Threshold Training workouts to drastically increase your lactic acid production, go here for the complete AT2 System!

– Dennis

Dennis Heenan

Dennis Heenan is the creator of Anaerobic Threshold Training (AT2). Dennis uses AT2 to teach people how to build such amazing physiques while working out for a fraction of the time that other people spend at the gym. Dennis believes that it takes a combination of hard work and smart work to see drastic improvements in your fitness.


Start burning more fat during AND after your workouts! <=

Credit: photo, photo, photo

Show/Hide Comments (11 comments)
  1. Chuck

    I appreciate this. It confirms a couple of things I’ve been researching in the work of Len Schwartz from “HeavyHands” fame. Of course he came before people talked about “HIIT”… He had a decent physique but never focused on isolation exercises much or sought to create a particular “look”.

    Before he died as his patent filings show (linked) he was focusing on trying to find the “sweet spot” between strength and endurance, muscle and cardio, and had moved from the “HeavyHands” alone to also doing bodyweight and isometric-like movements.

    I know we all want a quick workout and fast results but I’m thinking Schwartz may have been ahead of his time and anticipating the need for both…

    Thanks Todd for your work here – lots of thought provoking articles like this one!

  2. Nick

    Excellent article and advice!

    “Don’t put all your eggs in one basket.”

    • Todd Kuslikis

      Glad you liked it Nick!

  3. Christian

    How many time per weeks should I do this workout ? Do 3 times a day is enough?
    Thanks for your answer.

    • Christian

      I would say 3 times a week!

    • Todd Kuslikis

      Hi Christian, Totally depends on your goal and current fitness level.

  4. Raza

    Good article.

    P90x made it a household term, but Rusty Moore has been dispelling the hype around the “afterburn effect” for a while.

    With fitness, it seems like there always has to be a new buzz word to get people excited: Tabata, HIIT, Met Con, Anerobic Threshold, strength circuits, etc. Oh yeah, and there’s always some enemy (typically it’s slow cardio).

    At the end of the day, everything works. It all boils down to diet and how consistent you are with whatever workouts you’re doing anyway.


    • Todd Kuslikis

      Hi Raza, hit the nail on the head. The other component is that there is joy in certain exercises. Some people enjoy long-duration cardio. For example, I haven’t done any distance running for a long time. But I’m on vacation in Miami and went for a run with my brother in law. It was a great time to catch up and enjoy eachother’s company.

  5. Cholin

    “Over the 15 weeks, the HIIT group lost a whopping 0.2 pounds of fat.”

    “…the steady-state cardio group lost one pound of fat during their 20 weeks of training.”

    Math isn’t my thing so I’m confused… So the steady state cardio group lost 1lb and the HIIT lost .2lbs?

    • Andy G

      I agree, very confusing facts backing this article.

    • Dennis Heenan

      Cholin, YES! Those were the facts of the study which is what makes the study so interesting… You can pull two COMPLETELY different facts from the same study.

      The interval group saw better FAT LOSS while the cardio group saw better WEIGHT LOSS. Two very different things.

      The reasons people say the interval group burned 3X (or some exaggerate this to 9X) the fat as the cardio group is because they lost more body fat %. In other words, they added some lean muscle and lost body fat leading to better body composition.

      The cardio group was strictly weight loss (and probably some muscle loss too which leads to worse body composition).

      That’s where the confusion may be, and hope that cleared it up.

      -Dennis Heenan

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