ABSTRACT
The main component of daily energy expenditure in the average person is the energy expenditure for maintenance processes, usually called basal metabolic rate (BMR). The BMR is the energy expended for the ongoing processes in the body in the resting state, when no food is digested and no energy is needed for temperature regulation. The BMR reflects the body’s heat production and can be determined indirectly by measuring oxygen uptake under strict laboratory conditions. No food is eaten for at least 12 hours prior to the measurement so there will be no increase in the energy required for the digestion and absorption of foods in the digestive system. This fast ensures that measurement of BMR occurs with the subject in the postabsorptive state. In addition, no undue muscular exertion should have occurred for at least 12 hours prior to the measurement of BMR.
