Can training harder help you burn more calories both during the training bout and even after cessation of exercise? The short answer is "yes". Due to a phenomenon called Excess Post-Exercise Oxygen Consumption (EPOC), after an intense workout your body is in a state of oxygen debt. Basically, when your body is unable to keep up with the need for oxygen during exercise, it must work harder and longer to bring your body back into balance (i.e., homeostasis) post workout. This increase in effort from your body to catch up on oxygen requires energy, which means it also burns calories. So keep this in mind the next time you push yourself through an intense workout - the harder your train while you are in the gym, the more calories you will burn both during and after your routine.