Basal metabolism

Basal metabolism (BM) is a value that indicates the amount of energy to maintain all vital functions in a human body. The energy requirement above this basic level is determined by other activities of the organism (e.g. physical work).

Basal metabolism increases during food intake and nutrient digestion. Energy is used for their absorption and metabolism in the body. Specific-dynamic effect of food is the amount of energy that goes into their processing. It represents an average of 10% of the energy value of the nutrient mixture (more precisely, it is 4% for carbohydrates, 6% for lipids and 30% for proteins ). Basal metabolism depends on gender, age, body constitution (mainly height and weight) and hormonal regulation.

Measurement of basal energy consumption
To measure basal energy consumption, it is important to observe the following three conditions:


 * physical and mental state ;
 * fasting state (approximately 14-16 hours after the last meal, which should not contain proteins );
 * a thermoneutral environment (so that the thermoregulatory mechanisms are not stressed ).

As the BM is measured under very strict conditions, the measurement of energy consumption during rest is rather used and ideally ranges between 100%-115% of the BM.

Calculation of basal metabolic rate
BM can be calculated from the Harris and Benedict equation:

Calculation of BM for women

BMR = 655.0955 + (9.5634 × weight in kg) + (1.8496 × height in cm) − (4.6756 × age in years) kcal/day

Calculation of BM for men

BMR = 66.473 + (13.7516 × weight in kg) + (5.0033 × height in cm) − (6.755 × age in years) kcal/day

Related Articles

 * Metabolism
 * Thermoregulation

Literature

 * Protocols from physiology, Block III
 * Protocols from physiology, Block III
 * Protocols from physiology, Block III