L25 Central CV Adaptations to Training

Question 1

What are the functional adaptations of an aerobically trained heart

Answer 1

• endurance athletes have a greater ability to use the Frank-Starling mechanism to increase SV
  Athletes attain a large end-diastolic volume by virtue of enhanced left ventricle chamber compliance
• Total peripheral resistance is lower in athletes
• Emptying and filling of the is more efficient therefore a greater stroke volume .
• Maximal Cardiac Output increases

Question 2

Explain the changes that take place in the blood and plasma following exercise

Answer 2

Plasma volume expands to 800ml from 300ml

Due to increase in plasma protein production, changes in reflex regulation of body fluid volume, renin and aldosterone

Question 3

Explain the changes that take place in the erthrocytes and haemoglobin and blood volume

Answer 3

EPO controls production of red blood cells. More EPO = more red blood cells

Positive correlation between haemoglobin mass and VO2 max. This is the same correlation for blood volume and VO2 max

Question 4

Graphically illustrate how aerobic exercise training modifies SV, heart rate and CO responses to incremental dynamic exercise

Answer 4

SV increases and Heart rate decreases.

Maximal cardiac output increases

Question 5

Discuss the concept that cardiac hypertrophy can be sport specific and provide potential mechanisms for this

Answer 5

Eccentric hypertrophy
- increase in size of chambers, wall thickness, mass and stroke volume

Concentric hypertrophy
- Size of chambers stay the same but the wall thickness increases. There’s an increase in pressure generation

Question 6

Explain Athlete’s Heart syndrome

Answer 6

Sudden cardiac death

mainly due to hypertrophic cardiomyopathy