Whether you prefer strength training or cardio, you know that exercise burns tons of calories. Still, some forms of exercise burn even more calories long after training ends. This may sound too good to be true, but it is legitimate: During an intense workout, your body needs to transport enough oxygen and nutrients to your muscles. And when you stop moving, it doesn't automatically return to your normal metabolic function.
Rather, it takes your body some time to return to its natural state and actually demands more oxygen to do so, which in turn burns more calories. This is called the afterburner effect, or excessive oxygen consumption after exercise (EPOC).
What is the Afterburn effect or EPOC?
EPOC is the number of calories you burn above your resting metabolic rate after exercise. Although you burn a lot during your workout, the routines that create EPOC allow for more calories, especially from fat, typically peak in 45 minutes and can extend from 24 to 48 hours .
There are two kinds of workouts that have a great afterburner effect: high intensity interval training (HIIT) and high intensity steady state training (HISS).
Most people are familiar with HIIT workouts, but many may be doing HISS and calling it HIIT. HIIT involves intervals of maximum effort followed by longer recovery so that you can maintain that maximum effort during periods of work. On the other hand, HISS is when you exercise at high intensity and rest only long enough to complete each repetition in proper form.
Both are better than doing moderate to low intensity cardio workouts in steady state. Unlike steady-state cardio, which relies on your aerobic (oxygen-free) pathway to produce adenosine triphosphate (ATP), the fuel for your muscles, HIIT and HISS workouts rely on your anaerobic (oxygen-free) and aerobic pathways. for ATP.
The anaerobic pathways cannot supply ATP for a long time, so you can do a high intensity workout for a short period of time. Once ATP is depleted, you need to exercise at a lower intensity or take a rest interval to replenish it, allowing the aerobic pathway to kick in to supply more ATP.
This creates an oxygen deficit, which increases the afterburner effect, because your body will need more oxygen from the aerobic route to restore ATP and rebuild muscle proteins.
Your body also requires more oxygen to return to its normal metabolic function after intense exercises like HIIT and HISS. So, within 24 to 48 hours after completion, your body continues to work to get more oxygen, burning calories in the process.
According to experts, your body expends approximately 5 calories of energy for every liter of oxygen it consumes. The higher oxygen demand after training known as EPOC means you will burn more calories overall.
We all create a different afterburner effect, depending on your fitness level, the intensity and duration of your workout, and factors outside of your control, such as how your blood circulates and how your body breaks down and uses fat while you exercise.
However, the EPOC from a HIIT workout can increase your total calorie burn by 6 to 15 percent . If you burned 350 calories, you can burn up to an additional 53 calories due to the afterburner effect. Again, this is only a rough estimate; The calories you burn after exercise depend on your physical condition and other factors.
The benefits of the Afterburn effect
You will burn more calories without more effort
Of course, the most striking benefit of EPOC is the idea that you will burn calories, even at rest. And to maximize your calorie burn for every minute you spend exercising and after, HIIT and HISS are the way to go.
According to a March 2015 study published in the Journal of Strength and Conditioning Research, you can burn more calories during a 30-minute HIIT session than you can spend the same amount of time doing a steady-state cardio session. Unlike steady-state cardio, HIIT and HISS often incorporate elements of strength training , which can help build more lean muscle.
The more lean muscle you have, the more calories you burn, because muscle is metabolically active , which means it burns more calories at rest than body fat. While doing cardio will definitely get you burning calories, strength training not only burns calories during exercise, it also helps you build muscle, which contributes to overall calorie burn.
You can do shorter workouts
Although training time is shorter during HIIT, since EPOC increases exponentially with exercise intensity, short periods of exercise generate more EPOC than longer moderate-intensity workouts.
You could lose weight
HIIT and HISS exercise can amplify the effects of EPOC compared to the same amount of time you would spend exercising at a lower intensity, helping you in your weight loss efforts. A June 2017 review published in Obesity Reviews suggests that three weekly HIIT sessions can help reduce overall fat mass and waist size in obese and overweight people just as much as moderate intensity training, which requires more. weather.
You could improve your sports performance
Incorporating HIIT and HISS into a program to help improve specific sports performance not only reduces training time, but can also boost that performance.
A July 2016 study published in the Journal of Sports Sciences found that HIIT training helped rowers improve more than low-intensity, long-distance training. When the rowers included two HIIT sessions in a combination of 10 weekly workouts, they saw greater gains in performance than when they did 10 weekly aerobic sessions.
How to apply the EPOC effect to workouts
Coaches advise using a scale called the rate of perceived exertion (RPE), with one being the lowest exertion rate, also known as lying on the couch, and 10 being a sprint at full speed.
An RPE of seven is the intensity you want to aim for to start the afterburner effect, with an RPE of about three during a rest interval. The higher you go from there, the more EPOC you'll create and the shorter your workout can be.
Fortunately, there are many ways to practice HIIT and HISS, outside of the usual interval formula of 30 seconds of work and 30 seconds of rest.
The Tabata workout, for example, is a four-minute workout consisting of 20-second maximal effort intervals and 10-second rest periods. Given this work-rest relationship, it would be considered a HISS workout, not HIIT, as the limited amount of rest and heart rate recovery. You can add Tabatas at the end of your cardio or strength training to increase your afterburning power.
If you crave a little more variety in your HIIT workouts, consider HISS-style circuit training, in which you do an ordered list of exercises in a set number of reps and rounds. In circuit training, you will do consecutive exercises and recover for 30 to 60 seconds between sets. The beauty of circuit training is that you can target multiple muscle groups in one session.
The type of workout you choose will depend on your personal preferences, but they will have the same overall effect. Ideally, do HIIT twice a week, not on consecutive days, and balance it with regular cardio and non-intense strength training on other days.
5 types of HIIT and HISS workouts to turn on EPOC
- Tabata: Exercise for 20 seconds with maximum effort, then rest for 10 seconds. Repeat for four minutes.
- Every Minute in the Minute (EMOM): Do a set number of exercises in a specified rep range as fast as you can at the beginning of each minute and rest for the rest of the minute.
- As Many Rounds As Possible (AMRAP): Complete as many rounds as possible for a set of exercises with a specific rep range in a given amount of time.
- Circuit training : Do a series of exercises that target different muscle groups in a row and rest for 30 to 60 seconds between circuits.
- Ladder workout : Perform 10 reps of an exercise for the first round, then 9 reps for the second round and continue working your way down until you do one rep. Then rest for 30 seconds before climbing the ladder again.
