Answer:
Considerable amount of energy is required by the body to perform all the chemical reaction even when a person is at complete rest. This minimum level of energy required to exist is called BMR which accounts for about 50-70% of the daily energy expenditure in most sedentary persons.
Usual method for determining BMR is to measure the rate of oxygen utilisation over a given period of time
Maximum BMR is accounted for by essential activities of the central nervous system, heart, kidneys, and other organs, the variation in BMR among different person is related to mainly to different amount of skeletal muscle and body size.
Some factors that influence BMR:
- Thyroid hormone increases metabolic rate
- Male sex hormone increases metabolic rate
- Growth hormone increases metabolic rate
- Fever increases metabolic rate
- Sleep decreases metabolic rate
- Malnutrition decreases metabolic rate
Conditions to be maintained during BMR measurement:
- The person must not have eaten food for at least 12 hours.
- The BMR is determined after a night of restful sleep.
- No strenuous activity is performed for at least 1 hour before the test
- All psychic and physical factors that causes excitement must be eliminated.
- The temperature of the air must be comfortable and must be between 68 & 80°F.
- No physical activity is permitted during the test.