Overall Energy Requirements for Daily Activities

Overall Energy Requirements for Daily Activities

An average man who weighs 70 kilograms and lies in bed all day uses about 1650 Calories of energy. The process of eating and digesting food increases the amount of energy used each day by an additional 200 or more Calories, so that the same man lying in bed and eating a reasonable diet requires a dietary intake of about 1850 Calories per day. If he sits in a chair all day without exercising, his total energy requirement reaches 2000 to 2250 Calories. Therefore, the approximate daily energy requirement for a very sedentary man perform-ing only essential functions is 2000 Calories.

The amount of energy used to perform daily physical activities is normally about 25 per cent of the total energy expenditure, but it can vary markedly in differ-ent individuals, depending on the type and amount of physical activity. For example, walking up stairs requires about 17 times as much energy as lying in bed asleep. In general, over a 24-hour period, a person performing heavy labor can achieve a maximal rate of energy uti-lization as great as 6000 to 7000 Calories, or as much as 3.5 times the energy used under conditions of no phys-ical activity.