Does Orangetheory Work? On Heartrate-based Workouts

Heartrate-based workouts are nothing new but there is a new gym chain in town that claims to have cracked the code. So I did some undercover investigation to get the goods on whether or not the theory behind Orangetheory is flawed or fit.

Brock Armstrong
9-minute read
Episode #378

What Makes Orangetheory Unique?

As I said before, every day Orangetheory gyms around the world (from New York to Kuwait) all do the same workout. Sometimes it is the Endurance Workout (like the one I did), or a strength workout, or straight up HIIT (high-intensity interval training). I have to admit that when I asked more specifically about the workouts they had planned for the remainder of the week, they seemed pretty cloak and dagger about it, so I didn’t push it. But that did make my coachie-senses tingle. If participants don’t know what type of workout they are in for, how can they plan correctly to achieve a specific fitness goal beyond “get in shape?” More on that later.

According to their website, “Orangetheory is a 1 hour, full body workout, focused on training Endurance, Strength and/or Power. We use Heart Rate Based Interval Training, which burns more calories post-workout than a traditional exercise. When wearing our Heart Rate monitors, your real-time results are displayed on large screens throughout the studio.”

They go on to talk about how intensity is based on your individual Heart Rate zones (which they calculate for you based on the extremely rough equation of 220 minus your age), which they claim makes the workout effective for all levels of fitness. This is something I only partially buy at this point, but having had my butt handed to me today, I can’t really complain.

The gym space itself is definitely one of the most high-tech exercise spaces I’ve ever been in! There is a TV screen above the treadmills that displays your name, heart rate, percentage of your max heart rate, calories burned, and “splat points” which we’ll talk about next. There are also TVs in the weight room that display the exercises and reps so you can reference them during your workout if you forget what the instructor demonstrated.

The “splat points” are awarded to you when you are in the Orange and Red heart rate zones and are particularly sought after by Orangetheory goers not only because we all love to gamify our workouts (and have a way to quantify our hard work) but also because of a thing called “afterburn.” The OTF folks refer to those zones as the afterburn zones based on the notion that when your heart rate is up to or over 85 percent of your maximum, you continue to burn calories for 24 to 36 hours after the class is over.

Afterburn or EPOC

Getting in the "orange zone" produces what exercise physiologists call the “EPOC” effect (excess post-exercise oxygen consumption) AKA the afterburn.

Getting "splat points" for being in the orange zone produces what exercise physiologists call the “EPOC” effect (excess post-exercise oxygen consumption), AKA the afterburn.

The suggested biological reason for EPOC is “to restore the body to its resting state and allow for physiological adaptations” which will help the body handle the exercise (or stress) more easily in the future.

EPOC is at its most powerful immediately after the exercise session but some studies have found that EPOC can last up to 24 hours. (I didn’t find any that indicated 36 hours like OTF claimed.) It should also be noted that other studies have found that it lasts much shorter than 24 hours. In fact, some found that EPOC lasts less than an hour in some cases. There are many reasons for this discrepancy (gender, genetics, body composition, fitness level, etc.) but the important part is that the jury is still out on how much benefit you actually get from EPOC, or the afterburn.

Other research suggests that not only the duration but the actual calorie-burning effect of EPOC is much smaller than advertised and probably makes only a minor dent in weight loss compared to the energy cost of the actual exercise itself. Unless the exercise is undertaken regularly which is when the EPOC would have a cumulative effect.

In one study they found that the amount of extra energy burned during EPOC is only about 6-15% as much as is used during the exercise itself. So, 20 rounds of 1-minute running intervals performed at 105% of VO2max (which is an effort that we refer to as very, very uncomfortable), separated by 2 minutes of rest, burned an average of 537 calories during exercise, but only an extra 64 calories in the 9 hours after the session. Insert sad trombone sound.


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About the Author

Brock Armstrong Get-Fit Guy

Brock Armstrong was the host of the Get-Fit Guy podcast between 2017 and 2021. He is a certified AFLCA Group Fitness Leader with a designation in Portable Equipment, NCCP and CAC Triathlon Coach, and a TnT certified run coach. He is also on the board of advisors for the Primal Health Coach Institute and a guest faculty member of the Human Potential Institute.