Long term responses of exercise on the cardiovascular system

Download Report

Transcript Long term responses of exercise on the cardiovascular system

Long term responses
of exercise on the
cardiovascular
system
Cardiovascular system: cardiac hypertrophy;
increase in stroke volume; increase in cardiac
output, decrease in resting heart rate;
capillarisation; increase in blood volume;
reduction in resting blood pressure; decreased
recovery time; increased aerobic fitness
The Grades
• Look at the different descriptions below, and research as far as you feel you
need to:
• If you want to get a Pass, simply
– Describe what happens to the cardiovascular system when we start to
exercise, and after 6 weeks of training.
• If you want to get a Merit,
– Extend your description to include an explanation of how the cardiovascular
system responds when we start to exercise and after 6 weeks of training.
– You will need to provide some examples from sport in general and football in
particular here.
Cardiac Hypertrophy
• Increase in the size of the heart
– Increase in thickness of the myocardium
• Allows left ventricle to fill more completely during diastole
– Larger ventricular wall
• Can contract more forcefully
• Pumps more blood into the systemic system
• More efficient heart
Endurance athletes have larger
ventricle cavities and Anaerobic
athletes have thicker ventricle
walls.
Stroke Volume
• Due to Cardiac
hypertrophy, this
increases both at rest
and during exercise.
– Greatest amongst endurance
athletes
• Increased size of ventricular
cavity
• Up to 140ml per beat
• Improved contractility of the
myocardium
• In trained athlete at rest:
– EDV 130, ESV 40, SV 90
• In untrained athlete at rest
– EDV 130, ESV 60, SV 70
Heart
Rate
•
•
•
•
Resting heart rate untrained – 80bpm
Resting heart rate athlete – 60bpm
Resting elite endurance athlete – 35bpm
Bradycardia
– When h.r. falls below 60bpm
– Due to a slowing of the rate of the S.A.
node
• Lance Armstrong 35bpm
• Steve Redgrave 45bpm
• Cardiac output
– At rest – Same for athlete & non athlete
– Therefore, athlete has increased stroke
volume
– During exercise much larger for trained
athlete
Capillarisation
• Of trained muscles
Blood
pressure
• Decreases, particularly at
rest
– Mainly from endurance
training
• Blood pressure at a
maximal or sub-maximal
level remains unchanged
– New capillaries may
develop
– Existing capillaries become
more efficient.
• Brings about more
efficient delivery of blood
to working muscles
• More O2 reaches the
muscles
Vasculature
efficiency
• Particularly in the arteries
• More efficient vasodilation
& vasoconstriction
– Improves redistribution
of blood
– Better at shunting to
active muscles
Increase in blood plasma
• Increases blood volume
• Decreases blood viscosity
– Blood flows more easily
– Enhances delivery of O2 to the
muscles