Who doesn't like the concept of something for nothing, especially when it comes to exercise and calories burned? I am talking about "exercise afterburn" the concept that the body keeps burning extra calories post workout. It is true that we burn extra calories after exercising and it even has a very official sounding name: excess post-exercise oxygen consumption, or EPOC for short. It just seems that some of the claims about EPOC are wildly exaggerated, so let's set the record straight.
When you workout, your cells are essentially working out too. Post exercise, the cells need to restore their functioning to pre-exercise levels and that requires oxygen, which takes energy, aka calories. This cell restoration burns calories but not nearly as many as you might have heard. During an interview on the Fitness Rocks podcast, renowned sports physiologist Dr. Len Kravitz (not to be confused with renowned rocker Lenny) explained the afterburn phenomenon. Truth is that it really only lasts for two hours post workout.
To learn how many calories you burn, just
You only burn an additional 15 percent of the total calories expended during your workout. So if you burned 300 calories actively exercising at the gym, you will burn about an extra 45 calories over the next two hours. This figure of "15 percent" is on the high end as well.
While 45 calories may not sound like much, all those calories do add up. If you burn 300 calories three times in one week that is an extra 135 calories and that does feel a little like you are getting something for nothing. So work it, just don't rely on the afterburn. Just because you are exercising doesn't mean you can eat everything you want.