Exam 3 Review - lectures Flashcards
Equation for Stroke Volume
EDV-ESV
Equation for Ejection Fraction
SV/EDV
Normal Q
5 L/min
What is innervated by the sympathetic system in the heart
SA node, AV node, and the myocardium
What does an increase in sympathetic tone do
Increase contractility of the heart
How do you change sympathetic and parasympathetic tone
Higher brain centers, Chemoreceptors, Muscle Receptors, and Systematic Receptors influence the Medulla - with the vasomotor and cardiac center
Increase in sympathetic tone is caused by
Increased T (hypothalamus)
Increased emotional stress (cerebral cortex)
Increased movement (mechanoreceptors)
Increased PCO2, Increased H+, or Decrease PO2 (chemoreceptors)
What happens to SV when you go from laying down to standing up
It decreased due to the influence of gravity
What happens to SV when you go from laying down to running
Increase in SV
HR vs treadmill speed acute exercise
Linear increase in HR until you reach the HR max
What happens to HR, Qmax, and VO2max with age
All will decrease
Is HRmax a limit of speed?
No, it only limits the CV system
Does SV plateau, and if so, when?
Yes at about 40-60% of max intensity
What happens to EDV in acute exercise w/increase intensity and why
It increases until about moderate intensity due to an increase in venous return causing greater stretch and therefore a greater contraction. After it plateaus
What happens to ESV in acute exercise w/increase ex intensity and why
Not much change to it - If contractility increases it will decrease
What is Qmax
The point at which the heart cannot pump more blood
What happens to SBP with low-mod Intensity acute aerobic exercise
It increases due to the increase in Q
What happens to DBP with low-mod Intensity acute aerobic exercise
It decreases a little or it stays the same due to a reduction in peripheral resistance
What is the simple equation for MAP
1/3(SBP-DBP) + DBP
What happens to TPR with low-mod Intensity acute aerobic exercise
It will decrease due to vasodilation
What is the Rate Pressure Product (RPP)
It is a measure of the workload on the heart - HR x SBP
What happens to RPP with low-mod Intensity acute aerobic exercise
It plateaus
What happens to SV, HR, and Q with low-mod Intensity acute aerobic exercise
All will increase but are limited by max HR and SV
What is CV drift
A heart rate increase even with steady state exercise to try to compensate the decreased SV due to increased sweating - this is exacerbated in a hot environment