Resting metabolic rate

There are three components to daily human expenditure:
*basal metabolic rate (BMR) or resting metabolic rate (RMR)
*The thermic effect of food
*Daily physical activity

Resting metabolic rate also known as resting energy expenditure is the energy that is required by the body to sustain basic life processes such as respiration, heartbeat, renal function and blood circulation.

It also includes the energy needed to remain in an awake state, because the measurements are usually made shortly after the person wakes.

Two third of an individual’s daily energy expenditure can be accounted for from the resting metabolic rate. Resting metabolic rate can be measured by direct calorimetry or indirect calorimetry. Direct calorimetry measures the amount of heat lost by the body through radiative, convective and evaporative mechanisms.

Indirect calorimetry can be measured through total collection systems, open circuit systems, confinement systems or close circuit systems.

Resting metabolic rate is measured when the person is at rest in a comfortable environment. The fasting is only for 2 to 4 hours.

Factors that can influence a person’s resting metabolic rate:
*Ingesting food, especially a meal mixed with carbohydrates, fats and protein raises resting metabolic rate by approximately 5-10%

*Resting metabolic rate is a subject to changes in hormonal concentration. Two major hormones linked are epinephrine and thyroid hormone.

*The amount of lean body mass

*Body size and shape affect resting metabolic rate with stout and heavier individuals having lower rates than those that are tall and thin with the same body weight.

*Age. It has been reported that the resting metabolic rate per kilogram body weight in young children may be two times greater than in adults.

*Gender

*Climate changes, especially temperature changes can also raise resting metabolic expenditure.
Resting metabolic rate

What is Basal Metabolic Rate?

Basal metabolite rate or BMR is the rate at which the body expends energy for these life-sustaining activities.

It is the rate in which the energy uses for metabolism under specified conditions. It is usually expressed as kcalories per kilogram body weight per hour.

The basal metabolic rate of most people requires more energy than their voluntary muscular activity. Much of this energy is used to keep the body temperature constant.

The rate may vary from person to person and may vary for the same individual with a change in circumstances or physical condition.

Several factors affect an individual’s basal metabolic rate, including age, gender, height and weight.

The more a person weighs, the more total energy is expended in basal metabolism, but the amount of energy per pound of body weight may be lower.

Gender correlates roughly with body composition. Men generally have a faster metabolic rate than women, and researchers believe that this is because of men’s greater percentage of lean tissue.
What is Basal Metabolic Rate?