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EPOC: What It Is and How to Use it To Improve Client Results

Reading Time: 5 minutes 10 seconds


Date: 2022-06-21

People engage in personal training for many reasons. Some want a workout to increase muscle mass. Athletic clients might desire a training program that boosts their performance. Others are interested in a workout for weight loss or, more specifically, fat loss.

In the case of the latter, clients aren’t going to keep coming back if you don’t provide results. Maximizing EPOC is one way to help clients meet their weight loss goals in less time. Learn what EPOC is and the benefits it provides. We’ll also discuss how to use EPOC to enhance your clients’ training program results.

What Is EPOC?

EPOC is an acronym for excess post exercise oxygen consumption. It refers to the increased oxygen consumption that continues after exercise has ended. Metabolism is increased during EPOC as well. Increased metabolism results in increased calorie burn. Therefore, some know EPOC as the ‘afterburn effect.’

How Post Exercise Oxygen Consumption (EPOC) Works

The body uses oxygen during exercise. The greater the intensity of the workout, the more oxygen is needed to fuel the movement. (Higher intensity creates higher oxygen needs. Lower intensity creates lower oxygen needs.)

When an exercise session is high intensity, more oxygen is required. And the oxygen obtained through breathing isn’t enough. This results in an oxygen deficit. To resolve the oxygen debt, oxygen consumption is increased after the exercise has ended. This is known as the EPOC effect. 

Benefits of EPOC

EPOC increases caloric expenditure during the recovery period. When extra calories are burned, weight loss becomes easier. The number on the scale goes down faster while body measurements are also reduced. 

EPOC not only improves clients’ weight loss results, but it also stokes motivation. They see the progress of their training with greater speed. This increases their desire to continue with the exercise program. 

Knowing how to take advantage of the EPOC effect provides benefits to trainers too. If clients are interested in burning calories at a faster rate, they are going to come to you. This makes you a more sought-after fitness professional. It also boosts client retention. Clients will continue to work with you since you provide results.

EPOC Drawbacks

EPOC only occurs with more strenuous exercise. This means that clients can’t just go for a short walk or do a few push-ups and expect results. Their energy expenditure won’t increase for hours if the intensity isn’t there. They still have to put in the work upfront. They must do a high intensity workout if they want to enjoy the EPOC effect.

Clients also can’t use EPOC to justify eating more than is needed during exercise recovery. If they do high intensity exercise, then take in more calories than their body will use, they won’t lose weight. The afterburn isn’t enough to overcome excessive calorie consumption. Eat too much and they may even gain instead.

3 Ways to Maximize EPOC and Enhance the Afterburn Effect

How can clients maximize energy expenditure and increase oxygen consumption long term? Here are three strategies to consider.

#1: Increase Exercise Intensity 

Exercise intensity impacts how much afterburn occurs during the recovery period. Increasing intensity increases afterburn duration. 

When engaged in aerobic exercise, encourage clients to get their heart rate up. Ideally, their heart rate should be 65% to 85% of their max. An alternative is to use the rate of perceived exertion (RPE). 

Using the RPE scale helps clients know how hard to exercise when not training with you. It is also helpful when they don’t have access to a heart rate monitor. A good intensity to aim for is an RPE of 4 to 6. 

#2: Engage in Interval Training 

Research has found that high intensity interval training (HIIT) is great for EPOC. In fact, it is more effective at increasing energy expenditure than steady state exercise. One such study noted that EPOC burned more fat while increasing physiological response.

Interval training involves varying exercise intensity. High intensity exercise and low intensity exercise are alternated. This forces the body to work hard, then gives it time for a quick recovery. 

HIIT is known for increasing both fitness and calorie burn. Another benefit of HIIT is that the workout is shorter in duration. A typical HIIT session is 10 to 20 minutes in length. This means greater calorie burn while spending less time in the gym.

Incorporate a HIIT workout into your client’s training session. This helps to increase their calorie burn.

#3: Add Resistance Training

Many think of strength training as only a way to build muscle. But some studies confirm that it also increases oxygen consumption long after the exercise has ended. In one study, for instance, subjects had increased oxygen use for 14 hours after resistance training.

Resistance training offers an additional weight loss benefit. The more muscle one has, the more energy is needed to support that muscle. This also increases calorie burn, even while at rest. So not only does resistance exercise boost energy needs during recovery but also well past it.

Adding resistance training sessions can help enhance the EPOC effect. Aim for two to four sessions per week, depending on the client’s fitness level and goals. 

Combine All Three for Even Greater EPOC

Each of these strategies can increase oxygen used after exercise. Creating a training program that utilizes all three can boost energy used even more.

The client might engage in interval training Monday and Thursday, with resistance training on Tuesday and Friday. Or you might just kick up their cardio intensity a couple of days a week to elevate the EPOC effect.

How you structure the training depends on the client’s fitness level and goals. If they want to build more muscle, you might focus more on strength training than on increasing cardio intensity. If they want to bolster aerobic endurance, longer-duration cardio or HIIT can provide this effect.

EPOC Duration: How Long Does EPOC Last?

Of course, oxygen consumption does not increase infinitely after exercise. Generally speaking, EPOC can last up to 48 hours after the session has ended. That said, EPOC duration is influenced by a number of factors.

One factor to consider is intensity. Exercise that is higher in intensity will result in longer-lasting EPOC. Conversely, low intensity sessions will reduce EPOC. 

Exercise duration also affects EPOC. More energy is required to support longer exercise sessions. And more energy is used post-exercise as the body works to recover. 

One Final Tip About EPOC…

Greater exercise duration and intensity promote EPOC. Thereby, both improve calorie burn. Because of this, clients may be tempted to always go all out with their training sessions. They push themselves as hard as they can go. They give each session their all.

While this is okay from time to time, the body needs adequate time to recover. It needs enough downtime to undo the damage to the muscle. If it doesn’t get it, this opens the door to injury. It also increases the risk of burnout.

For this reason, doing interval training just once or twice a week is recommended. Limiting heavy resistance training also gives the muscle time to effectively recoup. Ultimately, balance is the key. Clients benefit from different intensity sessions. They also benefit from allowing adequate recovery. 

Want to learn more about how to promote healthy recovery for your clients? ISSA offers Exercise Recovery Specialist certification. This course teaches the effects of overtraining. You’ll also learn which strategies boost recovery best, thereby also boosting training results.

Featured Course

Exercise Recovery Specialist

ISSA's Exercise Recovery Specialization unlocks the science behind recovery techniques. As a Certified Exercise Recovery Specialist, personal trainers can apply this information to their exercise prescription and programs, helping athletes and general fitness clients alike.


Greer, B. K., O'Brien, J., Hornbuckle, L. M., & Panton, L. B. (2021). EPOC Comparison Between Resistance Training and High-Intensity Interval Training in Aerobically Fit Women. International journal of exercise science, 14(2), 1027–1035.

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