HEALTH FEATURE ARCHIVEThe metabolic rate is the amount of energy liberated per unit of time. Our metabolic rate is represented by the work we do, heat from body metabolism, and stored energy, such as in the form of fat.
The "basal metabolic rate" (BMR) is the metabolic rate determined at rest 12 to 14 hours after the last meal. In healthy humans the BMR is approximately 2000 kcal/day. (The metabolic rate is actually lowest during sleep.)
The metabolic rate is affected by recent food ingestion, muscle exertion, environmental temperature, height, weight, body surface area, age, sex, emotional state, body temperature, pregnancy, menstruation, level of thyroid hormones, and "stress" hormones (epinephrine and norepinephrine).