Cardiovascular Drift & AV02 Difference

Question 1

What is cardiovascular drift?

Answer 1

Cardiovascular drift is the increase in heart rate which occurs despite no change in the intensity of exercise.

Question 2

What is A-VO2 Difference?

Answer 2

Arteriovenous oxygen difference is the difference in oxygen concentration in the blood between arteries and veins.

Question 3

How does high intensity exercise effect A-VO2 diff. ?

Answer 3

High-intensity exercise will result in a greater A-VO2 diff as more oxygen is taken out of the arteries to fuel muscular contractions.

However, a plateau will be reached when more oxygen cannot be removed from the arteries.

Question 4

What’s the difference between a trained athletes and an untrained individuals A-VO2 diff?

Answer 4

Trained athletes will have a higher starting A-VO2 differences and will experience a bigger change during exercise.

Question 5

How does regular training affect A-VO2 Diff?

Answer 5

Regular training can increase the A-VO2 diff due to:
- greater capillary density
- greater alveoli density
- greater myoglobin in the muscles

Question 6

What 3 methods help redistribute blood to the working muscles?

Answer 6

• Vascular Shunt
• Arterioles
• Pre-capillary sphincters

Question 7

What is vascular shunt?

Answer 7

Vascular shunt is a mechanism which directs blood to the exercising muscles through vasodilation and vasoconstriction.

Question 8

Where is blood redistributed during exercise?

Answer 8

• Increase of blood flow to the skeletal muscles in order to supply them with oxygen and nutrients and to remove carbon dioxide
• Increase blood flow to the heart to provide additional oxygen, as it has to work harder during exercise
• Increased blood flow to the skin in order to regulate body temperature
• Decrease in blood flow to some non-vital organs to allow for greater blood flow to active body parts.

Question 9

How do arterioles help the redistribution of cardiac output?

Answer 9

• Widen (vasodilation) to allow more blood through

• Narrow (vasoconstriction) to reduce blood flow

Question 10

How do pre-capillary sphincters help the redistribution of cardiac output?

Answer 10

Open/close the entries to the capillaries to redirect blood flow into the cap areas where gaseous exchange is required.