Physiology Revision - Energy intake and expenditure

Question 1

What is total energy expenditure the sum of?

Answer 1

• Basal Metabolic rate; the amount of E expended while at rest
• The thermic effect of food; E required to digest/absorb food
• E expended during PA

Question 2

What does oxygen consumption (VO2) tell us?

Answer 2

All E-releasing rctns depend on O2, therefore VO2 is an indirect yet highly accurate measurement of E expenditure

Question 3

What is a Metabolic Equivalent of a Task?

Answer 3

Multiples of resting metabolic rate

• 1 MET = E expenditure for sitting quietly

Question 4

What is the formula for E expenditure?

Answer 4

E expenditure = Basal Metabolic Rate x Physical Activity level

Question 5

What is the definition of a calorie? What is the definition of a Kilojoule?

Answer 5

Calorie - 1 kilogram calorie (kcal) expresses the quantity of heat needed to raise the temp of 1 L or water by 1 degree

Kilojoule (KJ) - the standard unit to express food energy. Inhumans, 1 J = the E released in 1 second as heart by an average size person @ rest