Or EPOC (Excess Post-Exercise Oxygen Consumption) refers to the increased oxygen consumption above resting levels that the body is using to recover to a pre-exercise state.
Essentially your body maintains an increased metabolism (burning more calories) after exercise until recovery is complete. This can last from as little as 15 minutes to 48 HOURS afterwards!
As you would expect, the duration of After Burn is directly related to the INTENSITY and DURATION of the exercise performed. Countless studies have shown higher intensity interval aerobic activity yields a far longer after-burn than continuous steady-state cardio. For example one study, Laforgia et al. (1997) investigated the effects of a continuous run (30 minutes at 70% effort) versus a 20 bouts of 1 minute interval sprints (with rests in between), and found the After Burn to be more than DOUBLE in the sprint group compared to the other group!
But wait, there’s more!, HEAVY RESISTANCE training in the form of lifting weights (like Barbells, Dumbbells, Kettlebells, and some body weight exercises) has been shown to create MORE After Burn than both repetitive aerobic exercise (jogging, cycling) and circuit training (which requires lifting lighter weights for more reps); Elliot et al. (1988).
Think about this more efficient use of your time next time you hit the gym!!
NB: Anyone who doesn't understand the picture reference has clearly never seen TOPGUN. Shame on you.