Fat Burning Metabolism and Energy Systems 2

Question 1

What respiratory quotient (RQ) value indicates the body is primarily burning fat for fuel?

Accepted Answer

0.70

Answer

An RQ near 0.70 indicates fat is the primary substrate being oxidized; pure carbohydrate metabolism produces an RQ of 1.0.

Question 2

Approximately how many calories must be burned or restricted to lose one pound of body fat?

Accepted Answer

3,500 calories

Answer

One pound of stored body fat contains approximately 3,500 calories, so a total deficit of 3,500 calories — typically 500 calories per day over a week — is needed to lose one pound.

Question 3

Which energy system dominates during prolonged low-to-moderate intensity exercise lasting over 30 minutes?

Accepted Answer

Aerobic oxidative system

Answer

The aerobic oxidative system dominates during prolonged low-to-moderate exercise, using oxygen to oxidize fats and carbohydrates for sustained ATP production.

Question 4

What happens to fat utilization as exercise intensity increases toward maximum effort?

Accepted Answer

Fat utilization decreases as carbohydrates take over

Answer

As intensity rises, the body shifts toward carbohydrate metabolism because glycolysis produces ATP much faster than fat oxidation can, meeting the higher energy demand.

Question 5

What is 'metabolic flexibility'?

Accepted Answer

The capacity to switch efficiently between burning fat and carbohydrates based on availability

Answer

Metabolic flexibility is the body's ability to efficiently switch between fat and carbohydrate oxidation based on fuel availability and energy demands, a hallmark of good metabolic health.

Fat Burning Practice Test

Fat Burning Practice Test

Fat Burning Metabolism and Energy Systems 2