But while some boutique fitness classes promise your body to be in afterburn for 24 to 48 hours after a workout, Andrew said that's simply not the case. In fact, he said EPOC only lasts about one to two hours after a workout, which is why this is the optimal time to eat and refuel after an intense sweat sesh.
And it's not likely to burn hundreds of calories, either. Again, although every body is different and reacts differently to exercise, the EPOC effect burns roughly six to 15 percent of the total calories burned, Andrew said. So if you burned 200 calories during your workout, you will only burn an extra 12 to 30 calories after the fact.