What does EPOC stand for?

EPOC stands for Excess Post-exercise Oxygen Consumption, and describes the body's increased energy expenditure after a workout.

How long does the afterburn effect last?

The article states that afterburn can last 12-24 hours after HIIT and up to 48 hours after heavy strength training, depending on intensity, volume and type of training.

Which gives the most afterburn, strength training or HIIT?

Strength training often provides a longer EPOC because muscle repair and rebuilding require energy over time, while HIIT provides a high calorie burn quickly after the session. The article recommends combining the two for maximum effect.

How much protein should I eat to support the afterburn effect?

The article recommends 1.6-2.2 g of protein per kg of body weight to support muscle growth and recovery, along with a balanced intake of carbohydrates and fats for hormone production and energy levels.

Which types of training trigger the highest afterburn?

Anaerobic forms of training such as heavy strength training and HIIT trigger high afterburn, according to the Cleveland Clinic, because the body uses more energy during the session than it can supply and must work extra hard afterwards to restore balance.

What are the benefits of EPOC beyond burning calories?

The article lists increased hormone secretion (growth hormone, adrenaline, testosterone), improved insulin sensitivity and blood sugar stabilisation, increased metabolic activity on non-training days, more effective recovery and protein synthesis, and improved body composition over time.

Afterburn: How Strength Training (and HIIT) Boosts Your Resting Metabolism | Hardworkout Magazine

Key takeaways

- EPOC, or afterburn, is the extra oxygen the body consumes after training to refill glycogen stores, repair muscle tissue and stabilise temperature and pH – processes that keep calorie burn elevated for hours.

- Heavy strength training can keep afterburn going for up to 48 hours, while HIIT delivers a faster but shorter spike lasting roughly 12-24 hours.

- A 2024 study in Nature Scientific Reports found that HIIT produced significantly higher EPOC and fat oxidation than moderate-intensity training.

- Compound exercises, supersets with short rest periods and full-body sessions two to three times a week activate large muscle groups and maximise afterburn.

- A protein intake of 1.6-2.2 g per kg of body weight supports the muscle repair that drives much of the post-exercise energy expenditure.

Whether your goal is to shape your body, lose body fat, or build muscle, the combination of heavy strength training and the right diet is key. Excess Post-exercise Oxygen Consumption (EPOC) – allows the body to continue burning calories at rest, while muscle mass is built up with the help of proteins.

Here you will learn how to maximize your resting metabolism and get more out of each workout.

How does afterburn actually work in the body?

Afterburn, or EPOC (Excess Post-exercise Oxygen Consumption), describes the body's increased energy expenditure after a workout.

After intensive or heavy training, the body uses extra oxygen to restore balance, among other things to replenish glycogen stores, repair muscle tissue, and stabilize body temperature and pH levels.

These are energy-demanding processes – which means that you burn calories for many hours after the session is over.

[Cleveland Clinic](https://health.clevelandclinic.org/understanding-epoc) highlights that particularly anaerobic forms of training, such as heavy strength training and HIIT, trigger high afterburn.

During anaerobic training, the body uses more energy than it can supply during the workout, and therefore has to work extra hard afterward to restore balance. This process leads to higher afterburn.

EPOC can thus result in an increase in energy expenditure of 6-15% after training, and significantly contribute to fat burning during the recovery period.

A recent [study](https://www.nature.com/articles/s41598-024-59893-9) from 2024 shows how much difference various training forms can have on afterburn.

The study indicated that participants who completed HIIT sessions had significantly higher EPOC compared to those who performed moderate-intensity training.

Not only was the calorie expenditure at rest higher after HIIT, but fat oxidation also increased significantly in the hours afterward.

Why Strength Training and HIIT Provide High Afterburn

Heavy strength training and HIIT (high-intensity interval training) are both effective ways to trigger EPOC – the body's increased calorie burn after exercise.

Despite different physiological processes, they collectively contribute to increased energy expenditure, better body composition, and more effective training over time.

Strength Training

Activates large muscle groups – which increases oxygen demand during and after the workout, leading to higher energy expenditure at rest.

Causes small muscle damage (microtrauma) – which requires energy to repair and rebuild. This process can last for up to 48 hours.

Stimulates anabolic hormones such as testosterone and growth hormone – which contribute to increased muscle growth and a higher metabolism over time.

HIIT (High-Intensity Interval Training)

Training with very high intensity in a short time – which creates a great strain on the body and provides an acute high calorie burn.

Combines short work periods with minimal breaks – which leads to significant metabolic stress and high oxygen consumption during the session.

Provides a large calorie burn in a short time – which is especially effective for reducing body fat percentage and increasing afterburn, even with short sessions.

How many extra calories does afterburn actually burn?

The number of calories burned after exercise varies based on intensity, type of training, duration, and the person's muscle mass and training background.

- A heavy strength workout can increase resting calorie burn by up to 200 kcal the following day.

- HIIT sessions have been shown to burn 12-20 kcal more EPOC than moderate intensity training, even with the same energy expenditure during the session.

In addition, calorie burn can be further enhanced if one trains with higher volume, uses shorter breaks, and activates large muscle groups.

![hiit training](https://hardworkout.no/wp-content/uploads/2018/10/AdobeStock142125698.jpeg)

Which exercises and methods give the most afterburn?

For maximum afterburn, combine or vary between:

- Compound exercises (squats, deadlifts, rowing, bench press)

- Full body sessions (2-3 times per week)

- Supersets and short breaks (in strength training)

- Various HIIT sessions (e.g. 30 seconds work/15 seconds rest x 8-10 rounds)

- Sprint intervals, rowing, cycling, or bodyweight exercises with high intensity.

- Protein-rich diet – to support muscle building and recovery.

How long does the afterburn last?

The afterburn can last:

- 12-24 hours after HIIT.

- Up to 48 hours after heavy strength training.

- Depends on intensity, volume, and type of training.

Strength training often provides a longer EPOC as muscle repair and rebuilding require more energy over time.

HIIT, on the other hand, provides high calorie burn quickly after the session – and can be combined with strength for maximum effect.

How should you eat to get the most out of EPOC?

A good diet enhances the afterburn effect.

Eat plenty of protein (1.6-2.2 g/kg body weight) – this supports muscle growth and recovery, and prepares the body better to use energy to build and repair muscle tissue after training.

A balanced intake of carbohydrates and fats is also important for hormone production and energy levels – especially if the goal is to reduce body fat percentage without losing muscle mass.

![healthy diet](https://hardworkout.no/wp-content/uploads/2019/10/Webp.net-resizeimage-5-1.jpg)

The benefits of EPOC – beyond calories

- Increased hormone secretion (growth hormone, adrenaline, testosterone).

- Improved insulin sensitivity and stabilization of blood sugar.

- Increased metabolic activity even on non-training days.

- More effective recovery and protein synthesis.