7. The Athletic Heart Flashcards Preview

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Flashcards in 7. The Athletic Heart Deck (23):

What is the HR's response to dynamic exercise?

Roughly a tripling of HR

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How does training affect SV and HR?

  • Increased SV
  • Lower resting HR

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What is SV's response to dynamic exercise? How?

  • Increased filling due to:
    • Venous return
    • Preload
  • Increased emptying due to:
    • Frank Starling Law
    • Increased contractility

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How does peripheral resistance respond to the tissues' increased demand for O2?

Decreased peripheral resistance to flow

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How is blood flow to the organs redistributed w/ increasing exercise intensity?

  • Brain always gets constant amount
  • Flow to the heart and muscles increases proportional to exercise intensity
  • Flow to the kidneys, liver, stomach, intestines, etc. decrease as exercise intensity increases

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Arterial and venous pO2 at rest vs. during exercise

At rest:

  • Less O2​ extraction from blood
  • More oxygenated blood goes to veins

During exercise:

  • Increase in O2 extraction from blood
  • For same amount of O2 entering arteries, less O2 goes to veins

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What is CV drift?

A syndrome of CV destabilization during prolonged exercise that occurs w/ high workloads in hot environments


What causes CV drift?

Decrease in preload associated w/ relocation of central blood volume to the skin to dissipate metabolic heat


How does CV drift affect SV and systemic and pulmonary arterial pressure?

  • Decreased SV
  • Decreased pulmonary arterial pressure
  • Decreased systematic arterial pressure

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What are the hemodynamic responses to dynamic exercise?

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What are the hemodynamic responses to static exercise?

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How does plasma volume change w/ training? Significance?

Increased plasma volume makes blood less viscous and easier to flow


How do HR and BP adapt w/ training?

Decreases due to alterations in the balance b/t sympathetic and parasympathetic tone


How does SV adapt w/ training? Why?

Increased SV due to:

  • Reduced afterload (aortic pressure)
  • Increased diastolic filling time (slower HR)
  • Increased pressure of right atrial blood (volume load)


What are the benefits of a slower HR?

​Allows more time for diastolic filling and coronary perfusion


How is functional reserve altered w/ training?

Increased: can do same workload w/ less effort


Define orthostasis.

Maintaining upright posture


What is orthostatic hypotension? Symptoms? Cause?

  • Shift of blood from head and heart to veins in legs upon standing
  • Feeling of faintness due to sudden decrease in cerebral perfusion pressure due to reduced arterial blood pressure
  • Most likely due to increased parasympathetic drive in trained athletes which leads to a slight delay in the autonomic nervous response upon standing


What is concentric hypertrophy of the heart? Causes?

Response heart makes to chronic pressure loading (hypertension) in which the walls start to move toward center

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What is eccentric hypertrophy?

Wall thickens in proportion to increase in blood volume due to increased preload

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How are sarcomeres added in response to pressure load? What type of hypertrophy does this promote?

In parallel --> concentric hypertrophy

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How are sarcomeres added in response to volume load? What type of hypertrophy does this promote?

In series --> eccentric hypertrophy

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What constitutes normal, athletic hypertrophy of the heart?

  • Adaptive
  • Symmetric wall growth
  • Reversible training effect
  • Diastolic function is preserved