Hvileforbruk

Hvileforbruk, or hvileenergiomsetning, describes the amount of energy the human body uses at rest to maintain vital physiological functions such as breathing, circulation and cellular processes. It is typically measured under strict conditions: in a thermoneutral environment, after overnight fasting and in wakefulness. The most precise measurement is indirect calorimetry, which estimates energy expenditure from oxygen consumption and carbon dioxide production. In practice, resting energy expenditure is often estimated with predictive equations, such as the Mifflin–St Jeor equation.

Typical values for adults vary with body size and composition. For many adults, hvileforbruk falls roughly in the range of 1,200–1,800 kcal per day for women and 1,500–2,200 kcal per day for men, with larger or leaner individuals having higher values. It is closely linked to fat-free mass, and thus tends to decline with age and changes in body composition.

Several factors influence hvileforbruk, including age, sex, body composition (especially fat-free mass), hormonal status, temperature, sleep, and recent meals or illness. It is distinct from total energy expenditure, which also includes physical activity and the thermic effect of food. BMR (basal metabolic rate) is a related concept measured under stricter fasting and posture conditions; hvileforbruk/resting energy expenditure approximates BMR for many purposes.

Applications include nutrition planning, weight management, and clinical assessment. Limitations include day-to-day variation, measurement conditions, and the use of predictive equations that may introduce error.