It's important to know that our bodies have several ways of expending energy, and one of them comes from your own metabolism. It's part of the calorie-elimination process. But how, you might ask? The foods that we eat are composed of nutrients. In order for these nutrients to be absorbed by the body, your metabolism has to use energy to break them down. This bodily characteristic allows us to burn even more calories. Cool, right? Don't get too excited—this just means that your body expends some energy while digesting food, but it still doesn't compare to the benefits of a great workout.