what percentage higher is the metabolic rate of males compared to females?

Question

apparently it is higher because it's part of my nutrition lab. Plus it makes sense considering the body composition of males compared to females

ugh copy and paste doesnt help

Answer 1

that is mainly dependent on the amount of fat free mass the individual has. in general men produce 10x the amount of testosterone that women do. this is why men have significantly more muscle mass then women. their bodies do not produce enough testosterone so the level of circulating androgens in the body is low. it is physiologically impossible to have a high amount of muscle mass with low levels of circulating androgens. the levels of the sex hormones are the primary difference between males and females.

all of that being said if you had a man and a woman both with equal amounts of fat free mass at the same level of fitness their BMR would be comparable

Answer 2

Richard is right. Globally, there's a small surplus of men. It varies somewhat per country. War can create a significant surplus of women, as in Cambodia. There is also a female surplus in the U.S. black population. Selective abortion or neglect of girls currently generates a male surplus in China and India. Also, as the difference between male and female smoking behavior decreases, the life span of males and females becomes more similar. And less and less men work in traditional worker killing industries such as mining. On the other hand, better health care combined with lower birth rates reduces the death of women related to childbirth. But overall, I think the surplus of men will increase in the future.

Answer 3

Both basal metabolic rate and resting metabolic rate are usually expressed in terms of daily rates of energy expenditure. The early work of the scientists J. Arthur Harris and Francis G. Benedict showed that approximate values could be derived using body surface area (computed from height and weight), age, and sex, along with the oxygen and carbon dioxide measures taken from calorimetry. Studies also showed that by eliminating the sex differences that occur with the accumulation of adipose tissue by expressing metabolic rate per unit of "fat-free" or lean body weight, the values between sexes for basal metabolism are essentially the same. Exercise physiology textbooks have tables to show the conversion of height and body surface area as they relate to weight and basal metabolic values.

The primary organ responsible for regulating metabolism is the hypothalamus. The hypothalamus is located on the brain stem and forms the floor and part of the lateral walls of the third ventricle of the cerebrum. The chief functions of the hypothalamus are:

control and integration of activities of the autonomic nervous system (ANS)
The ANS regulates contraction of smooth muscle and cardiac muscle, along with secretions of many endocrine organs such as the thyroid gland (associated with many metabolic disorders).
Through the ANS, the hypothalamus is the main regulator of visceral activities, such as heart rate, movement of food through the gastrointestinal tract, and contraction of the urinary bladder.
production and regulation of feelings of rage and aggression
regulation of body temperature
regulation of food intake, through two centers:
The feeding center or hunger center is responsible for the sensations that cause us to seek food. When sufficient food or substrates have been received and leptin is high, then the satiety center is stimulated and sends impulses that inhibit the feeding center. When insufficient food is present in the stomach and ghrelin levels are high, receptors in the hypothalamus initiate the sense of hunger.
The thirst center operates similarly when certain cells in the hypothalamus are stimulated by the rising osmotic pressure of the extracellular fluid. If thirst is satisfied, osmotic pressure decreases.
All of these functions taken together form a survival mechanism that causes us to sustain the body processes that BMR and RMR measure.


[edit] The Harris-Benedict equations
The original equations from Harris and Benedict are:

for men,
for women,
where h = total heat production per 24 hours at complete rest in kcals, w = weight in kilograms, s = stature (height) in centimeters, and a = age in years, and with the difference in BMR for men and women being mainly due to differences in body weight.[2]


[edit] Example calculation
As an example, for a 55-year-old woman, an estimated BMR might be 32 kilocalories (kcal) per square meter per hour. If her body surface area were 1.4 m², the hourly energy expenditure would be 44.8 kcal/h (32 kcal/(m²·h) x 1.4 m²). This amounts to an energy expenditure of 1075 kcal per day (44.8 kcal x 24). The value of 1075 kilocalories, then, is the resting metabolic rate; or, if the more stringent measurement conditions were met, it could also be the basal metabolic rate. A detailed non-metric formula for BMR can be found at this link [1]

Hope this helps.

Answer 4

5-10% lower cause women are generally less active

Answer 5

there is no variance over all between male and female, metabolic rate is tied to activity levels, not gender.