BMR Flashcards
what is the typical adult energy need
10MJ
what is BMR
the energy to pump blood, sustain cellular processes and the minimal metabolic activity to maintain 37 degrees
how much energy is radiated as infrared from an average adult
100Watts
function of bomb calorimetry
gives a direct measure of energy of combustion in food
what is the bomb calorimetry equation
food + oxygen –> H20 + CO2 + NxOx + heat
what are the kJ/g of fat, alcohol, carbohydrates and protein
fat - 37 kJ/g
alcohol - 30 kJ/g
carbohydrate 17 kJ/g
protein - 16 kJ/g
what are Atwater factors
the kJ/g of a substance
what is specific dynamic effect
the energy used after feeding
what can elevate specific dynamic effect
high protein contents in the diet
what causes the energy usage of specific dynamic effect
absorption and transport of nutrients, digestive enzyme synthesis, gut mobility and gut replacement
what relationship does BMR have to body size
the larger the animal the lower the BMR (more efficient)
explain the change in BMR over a lifetime
children have relatively higher BMR due to size and growth
Adult BMR decreases by 2% for ever 10 years after the age of 20
how does body fat affect BMR
high body fat decreases BMR due to:
- greater insulation against heat loss
- fat need only little energy to store
why does adult BMR decrease over age
due to fatty infiltration and replacement of muscle
why does a male require 1MJ more energy than women a day
because males have a higher lean mass and therefore need more energy to maintain
(women have more fat stored - require less energy to maintain)
