When you think about burning calories, you probably think about burning calories during your workouts—like while you’re on the treadmill or under the squat rack.
Depending on your workout, however, you also continue to burn calories after you leave the gym—especially important if you’re trying to shed fat. These calories, which you’ve probably heard referred to as the ‘after-burn,’ come from excess post-exercise oxygen consumption, or EPOC.
EPOC, simply put, is the amount of oxygen (and therefore calories) that your body churns through after your workout to restore your body to its previous state. Your body uses this post-exercise oxygen to restore the glycogen (energy) in your muscles, lower your body temp, and repair damage to your muscles, says Pam Geisel, M.S., C.S.C.S., C.P.T., exercise physiologist at the Hospital for Special Surgery’s Tisch Sports Performance Center in New York City. EPOC gives your metabolism gets a nice little boost, which can last anywhere from three to 24 hours after you leave the gym.