1.2.5 the relationship between stroke volume, heart rate and cardiac output at rest and during sub-maximal and maximal activity

Question 1

heart rate (BPM or HR)

Answer 1

BPM INCREASES

• heart rate increases linearly with exercises intensity
• max heart rate is 220 minus ages
• steady-state relates to the straight line in a graph when the oxygen supply meets the oxygen demand

Question 2

stroke volume (SV)

Answer 2

INCREASES to allow for more oxygen to be delivered to working muscles to create energy.
increases with intensity to a certain point

Question 3

cardiac output (Q)

Answer 3

INCREASES due to increase in both HR+SV

increases with intensity

Question 4

systolic blood pressure

Answer 4

increases due to an increase in HR, SV + Q because more blood is being forcefully pumped into arteries
however diastolic blood pressure doesn’t change because its relaxation and the filling phase cannot change, despite demand

Question 5

blood flow redistribution

Answer 5

During exercise blood flow is redistributed to the working muscles and away from areas that are less needed for activity such as the gut and kidneys.

At rest blood flow to muscles is approx. 15 to 20 per cent.
during exercise, increases to 80-90%

This occurs by vasodilation of the capillaries at the muscles and vasoconstriction of the capillaries at the organs.

Question 6

blood volume

Answer 6

DECREASES due to loss of plasma in sweat.

the amount decreases depends on intensity and duration

Question 7

acute responses

Answer 7

the bodies immediate, short term responses that are only present during the physical activity and during recovery (until resting levels are achieved)