What is Excess Post-Exercise Oxygen Consumption (EPOC)?

by Matt Weik

There seems to be much talk about excess post-exercise oxygen consumption (EPOC) and if it’s something we should focus on when it comes to helping achieve the health and fitness results we want. The answer to this is yes.

Excess post-exercise oxygen consumption is the amount of oxygen consumed in excess of what’s required at rest. During intense exercise, especially weight training and sprinting, the body uses far more energy than can be obtained through muscle contractions alone. The difference between the amount of energy required to perform a workout and what is obtained from muscle contraction is attained by breaking down glycogen, triglycerides, fat, and proteins. This energy is released in the form of heat, and EPOC helps cool the body down by dissipating this heat.

You may have also heard EPOC referred to as “The Afterburn Effect.”

EPOC: The Use of Energy by the Body After Exercise

The higher the intensity of the workout, the greater is the duration and the degree of EPOC after the workout.

When we are done with our workout, we allow our body to return to its resting state. Energy is used in this recovery process, which is when additional calories are burned. Our metabolism continues to burn calories during this process, even when we are at rest.

Though no specific time frame is agreed upon by researchers, it is believed that the recovery period could be anywhere from 15 minutes to 48 hours following a workout. So, we can say that excess post-exercise oxygen consumption lasts for that duration after the exercises are performed.

Here are some key factors that contribute to an increased EPOC:

  • EPOC seems to have a considerable impact on caloric burn
  • High-intensity cardio, a fast-paced workout session, circuit training, and heavy resistance training seem to have a remarkable effect on EPOC
  • Increased respiration
  • Increased heart rate
  • Increased core temperature
  • The re-synthesis of lactate to glycogen
  • When myoglobin and hemoglobin are re-oxygenated
  • When hormones like thyroid, cortisol, insulin, etc., become elevated

Training Methods Known to Create a Maximum Effect with Excess Post-Exercise Oxygen Consumption

Many modalities have been suggested for the maximum effect of excess post-exercise oxygen consumption. Among them, the most popular training methods are:

1.      Interval Training

Adding this method to your workout routine helps us increase our strength and endurance at a much faster pace. Activities such as jumping rope and running stairs benefit the cardiovascular system, balance, agility, and build sprinting power. This type of training puts you in both high and low energy outputs. You can think of it as a sprint followed by a walk, and then the cycle repeats.

2.      Tempo Training

The tempo training method is another power training modality. When this training is included in our routine workout, a tempo or speed is set to build more muscles, improve strength, and help increase fat loss. Activities like running, cycling, rowing, etc., fall into this category.

3.      Circuit Resistance Training

This method of training includes high power resistance and endurance training, and even aerobics. The goal is to build up strength and muscular endurance. Some people think that circuit resistance training only involves specific exercises and movements for various body parts, but this training method really opens the door for you to be creative with your exercise selection. The key is to move from one exercise to the next with minimal rest in between.

4.      Heavy Resistance Training

Heavy resistance training consists of exercises that cause intense muscle contractions against an external resistance with the goal of increasing strength and muscle size. This external resistance could be your body weight, dumbbells, a barbell, or any other type of weight that could cause the muscles to contract. Squats, deadlifts, push-ups, lat pulldown, bent over row, and bench press are a few of the exercises recommended in this training method.

Getting the Most from Your Training

A more significant effect of EPOC is yielded during the post-exercise recovery period. Just because you’re done with your workout doesn’t mean your body simply shuts down and goes to sleep.

Oxygen is also used for some other functions immediately during the post-exercise recovery period. It restores oxygen levels in venous blood, skeletal muscle blood, and myoglobin. Muscles and tissues that get damaged during the workout are repaired due to the breakdown of protein into amino acids that help kickstart the recovery process. It also helps restore your body temperature to resting levels.

The excess post-exercise oxygen consumption from a high-intensity interval training or “HIIT” shows an incredibly beneficial effect, and strength training workouts offer the ability to add 6 to 15 percent of the total energy cost of the workout session.

Excess post-exercise oxygen consumption is influenced by the intensity and not the exercise duration. The research has shown that resistance training can have a greater impact on the EPOC effect than running at a steady speed.

Putting it all together and to close out our article on EPOC, here is what the research says:

In an extensive review looking at excess post-exercise oxygen consumption, Bersheim and Bahr (2003) concluded that “studies in which the similar estimated energy cost or similar exercising VO2 have been used to equate continuous aerobic exercise and intermittent resistance exercise, have indicated that resistance exercise produce greater EPOC response.”