Energy Expenditure

Question 1

What is a calorimeter?

Answer 1

How they establish how many calories food contains. It oxidises the sample which warms the water up. The increase in temperature is used to work out how many calories are in that sample.

Question 2

Pros of direct calorimetry

Answer 2

Direct measure of heat
Accurate for steady state measures

Question 3

Cons of direct calorimetry

Answer 3

Expensive
Slow to generate results
Few in operation
Accurate for exercise?

Question 4

Benefits of direct calorimetry

Answer 4

Can detect changes during exercise with breath by breath symptoms
No longer affected by the heat of equipment
Easy to administer
Fairly accurate for aerobic measures
Direct assessments of gas exchange

Question 5

Indirect Calorimetry Assumptions

Answer 5

Body’s O2 content constant
Little contribution from protein during exercise (Non protein RER)

Question 6

Indirect Calorimetry Limitations

Answer 6

CO2 released in the lung may not be representative of CO2 released by working cells
Protein contributes up to 5% of total energy in prolonged exercise

Question 7

What is fat max?

Answer 7

Exercise intensity at which maximal fat oxidation is observed. The facilitation of fat metabolism important for health and performance. It is explained by: lower availability of plasma FFA (free fatty acids), reduced entry of fatty acids into mitochondria.

Question 8

Definition of Mechanical Efficiency

Answer 8

External work accomplished / energy expenditure

Question 9

What does EPOC stand for?

Answer 9

Excess Post-exercise Oxygen Consumption

Question 10

Fast EPOC

Answer 10

Rapid decline in oxygen uptake during the first 2-3 minutes following exercise
Resynthesis of ATP and PCr
Oxygen levels restored to myoglobin and haemoglobin
Thermogenic effects of hormones

Question 11

Slow EPOC

Answer 11

Occurs 2-3 min and persists for up to an hour following exercise cessation
HR and VE remain elevated for several minutes after exercise
Thermogenic effects of elevated core temperature
Resynthesis of lactate to glycogen

Question 12

What does Oxygen Deficit represent?

Answer 12

A lag in O2 uptake response, until steady state occurs

Question 13

What does EPOC represent

Answer 13

A delay in the recovery of oxygen consumption

Question 14

What is the Ultraslow Portion of EPOC?

Answer 14

Can persist for several hours before basal level returns