Excess Post-Exercise Oxygen Consumption (EPOC)
Excess post-exercise oxygen consumption (EPOC) refers to the increased intake of oxygen after you finish exercise. In other words, once you finish running hard, you continue breathing hard a while longer. The purpose of EPOC is to eliminate the “oxygen debt” that accrues during exercise, bringing your body back to a resting state. EPOC is greater with higher intensity exercise that targets the anaerobic system. But EPOC is why higher intensities that primarily target the anaerobic system also train the aerobic energy system; this is because the oxidative (aerobic) energy system works hard to bring you back to a baseline level after finishing those hard intervals.