Basal metabolic rate (BMR) is the rate of energy metabolism in awake and extremely quiet conditions. A difference of 10% to 15% between the morning and evening BMR is normal. The formula for calculating basal metabolic rate is (pulse rate + pulse pressure) – 111, with a normal range of plus or minus 15%. The level of basal metabolic rate is related to the individual’s body size, gender, age, ambient temperature and thyroid function. Generally speaking, it is higher in men than in women, and higher in children than in adults, and it is important to measure basal metabolic rate when the body is relaxed, free of mental stress, awake and lying down. To ensure the normal fluctuation of the basal metabolic rate, it is necessary to get enough sleep, consume enough calories, eat more protein foods, exercise appropriately, keep a happy mood, and consult a doctor if you feel unwell.