Metabolic rate is the rate of metabolism, the amount of energy used by an animal per unit of time. Basal metabolic rate (BMR) is the amount of energy used daily by animals at rest.

Processing food after eating uses chemical energy and produces some heat

About 70% of a human's total energy use is due to the basal life processes within the organs of the body (see table). About 20% of one's energy use comes from physical activity and another 10% from the digestion of food after eating.