cardiovascular system responses and adaptations

Question 1

responses to a single exercise session

Answer 1

1. anticipatory rise in heart rate prior to exercise
2. increased heart rate
3. increased cardiac output
4. increased blood pressure
5. redirection of blood flow

Question 2

1. anticipatory rise in heart rate prior to exercise (R)

Answer 2

• you may feel your heart rate increase prior to exercise
• this is due to the release of adrenaline
• this is known as anticipatory rise
• it is preparing your body for increased demands

Question 3

2. increased heart rate (R)

Answer 3

• hr increases due to the rise of carbon dioxide picked up by chemoreceptors
• as increase in hr is needed due to an increase in demands of oxygen

Question 4

3. increased cardiac output (R)

Answer 4

cardiac output = stroke volume x heart rate
stroke volume = amount of blood ejected from heart per minute
heart rate = amount of heart beats per minute
cardiac output = amount of blood pumped in 1 minute
- when we exercise, the demand of oxygen increases, therefore heart rate, stroke volume and cardiac output increase

Question 5

4. increased blood pressure (R)

Answer 5

• blood pressure increases during exercise as more blood is pumped throughout blood vessels
  blood pressure = pressure of blood against wall of arteries
• blood pressure has 2 readings 120/80 systolic and diastolic
  systolic = top no. records pressure on artery when heart contracts
  diastolic - bottom no. records pressure on artery when heart relaxes

Question 6

5. redirection of blood flow (R)

Answer 6

• blood is redirected where it is needed the most, when exercising
  the blood is needed for the working muscles and the blood vessels
  will vasodilate to allow this extra blood flow.
• during exercise blood is not needed for the digestive system
  blood flow is reduced to this area by vasoconstriction

Question 7

adaptations of CV to exercise

Answer 7

1. cardiac hypertrophy
2. increase in resting and working stroke volume
3. decrease in resting heart rate
4. reduction in resting blood pressure
5. decrease heart rate recovery time
6. capillarisation of skeletal muscle and alveoli
7. increase in blood volume

Question 8

1. cardiac hypertrophy (A)

Answer 8

walls of the heart get thicker, increasing the strength of contractions

Question 9

2. increase in resting and working stroke volume (A)

Answer 9

• cardiac hypertrophy means that the heart can pump more blood per beat (stroke volume)
• more blood means more oxygen can be transported to the working muscles during exercise

Question 10

3. decrease in resting heart rate (A)

Answer 10

• because the heart is bigger and can pump more blood per beat, the heart does not have to work as hard
• results in a reduced resting heart rate

Question 11

4. reduction is resting blood pressure

Answer 11

• training reduces blood pressure
• this reduces risk of heart disease and stroke
• exercise keeps our blood vessels healthy

Question 12

5. decrease heart rate recovery time

Answer 12

because the heart is bigger it can not only pump blood at an increased rate during exercise, it does this after exercise which decreases recovery time and removes waste products at a faster rate

Question 13

6. capillarisation of skeletal muscle and alveoli

Answer 13

• exercise increases the capillarisation both around muscle and alveoli
• this means more oxygen and nutrients can be diffused into the blood from the alveoli and into the muscle

Question 14

7. increase in blood volume

Answer 14

training increases blood volume, mainly due to capillarisation through training
- this allows more oxygen and nutrients to be delivered around the body
- you can also regulate temperature more efficiently