Energy Balance

Question 1

What is calorimetry?

Answer 1

Calorimetery is the measure of energy expenditure it can be measured directly, indirectly or by double labelled water

Question 2

What is double labelled water?

Answer 2

Best way to measure a persons energy expenditure
Measures energy expenditure in any environment without interference of behaviour of subject
Much better use of measurement to measure persons diet as they do not have to record/recall their own diet
Objective measure - minimises bias e.g. bio marker which use blood and urine samples
Problem: very expensive, requires people to give lots of samples, lots of commitment

Question 3

What is BMR?

Answer 3

Energy expended at rest, energy expended to fulfil life sustaining functions. Strict conditions - relaxed state physically and mentally, thermo-neutral environment, fasting for 12 hours, well-rested

Question 4

What is REE?

Answer 4

Energy expended at rest, energy expended to fulfil life sustaining functions, no strict conditions, so easier to measure

Question 5

What is DEE?

Answer 5

Diet induced thermogenesis, energy needed for digestion and processing of food, ~10% of energy, varies with diet composition
Determined by amount of food and composition, hormones/SNS

Question 6

What is AIEE?

Answer 6

Most variable component, measures physical activity
Determined by intensity, duration, body weight, genetics

Question 7

What is energy balance?

Answer 7

Energy balance, energy in = energy out fluctuates throughout day, highly variable, energy balance achieved over longer period
Positive energy balance if energy in > energy out results in growth
Negative energy balance if energy in < energy out results in weight loss
If amount of energy in drops, slows growth in children and people will be hungry