exercise phys exam 3 study guide
what is VO2? - correct answer oxygen consumption
product of cardiac output and (a-v )O2 difference
depends on work intensity
VO2max - correct answer •measure of the maximal rate at which ATP is generated through
oxidative phosphorylation
•Sets the upper limit for endurance performance
-not a good predictor of performance in runners with similar VO2max values
•HRmax × SVmax × (a-v)O2 differencemax
-Gold-standard measure of cardiorespiratory fitness
-typically expressed clinically in relative (mL ∙ kg−1 ∙ min−1) terms
-Allows comparisons between individuals of different body weights
how do you do more work without consuming more oxygen? - correct answer anaerobic
respiration
relatoinship between weight and O2 - correct answer bigger people have to consume more O2
Heart Rate increases in proportion to _____________________. - correct answer exercise intensity
(work rate)
HRmax - correct answer where HR begins to plateau
relationship between HR and exercise - correct answer Before exercise, an anticipatory response
causes HR to increase above resting heart rate (RHR) due to a decrease in vagal tone and an increase
in norepinephrine and epinephrine. During submaximal exercise, HR increases linearly, leading to a
steady-state HR. This steady-state HR can be used to estimate aerobic fitness and HRmax.
HR is directly proportional to exercise
relationship between HR and VO2max - correct answer higher HR has lower VO2max because
higher intensity
,what is SV determined by? - correct answer -Venous return
-Ventricular distensibility
-Ventricular contractility
-Aortic or pulmonary artery pressure
stroke volume in response to exercise - correct answer increased SV with increased exercise
intensity up to 40 to 60% VO2max
-Beyond this, SV tends to plateau
most important determinant for VO2max
there is a plateau because you can only fit so much blood in the heart
Stroke Volume increases due to increased ___________ and increases ________________. - correct
answer venous return; contractility
what is preload? - correct answer end-diastolic ventricular stretch
what does an increase in preload lead to? - correct answer An increase in preload (i.e., increased
end-diastolic volume or EDV) leads to a stronger contraction of the heart because increased stretch
leads to greater contraction strength (Frank-Starling mechanism)
VC of inactive tissues, increased respiratory and muscle pump activities leads to increased venous
return, which helps to drive more blood back to the heart. At high exercise intensities, an increase in
HR can reduce filling time, causing a slight decrease in EDV and a plateau in SV.
What is contractility and what causes it to increase? - correct answer inherent ventricle property
norepinephrine and epinephrine lead to increased contractility
-Independent of EDV (increased ejection fraction instead)
cardiac output - correct answer The volume of blood ejected from the left side of the heart in one
minute.
HRxSV
due to increases in HR and SV
-Differences primarily due to differences in stroke volume
, increases with increased exerv=cise intensity and plateaus near VO2max
difficult to measure, so measure VO2max instead
what is the primary determinant of VO2 max? - correct answer cardiac output
Qmax - correct answer a function of body size and aerobic fitness
•70-85% of limitation in VO2max is linked to maximal cardiac output
Mean arterial pressure increases in proportion to _______________. - correct answer exercise
intensity
During endurance exercise, mean arterial pressure (MAP) increases because: - correct answer -
Systolic BP increases proportional to exercise intensity
-Diastolic BP slight decreases or slight decrease (at max exercise)
MAP - correct answer •Q x total peripheral resistance (TPR)
-Q inceases, TPR decreases slightly
-Muscle vasodilation versus sympathetic vasoconstriction in other tissues
increases in proportion to exercise intensity
Rate-pressure product (RPP) - correct answer = HR x SBP
-Important determinant of myocardial oxygen uptake and myocardial blood flow
what does it mean if bp is not increasing with more work, reducing cardiac output? - correct
answer heart is failing, blood is leaking, could be internal bleeding or ischema
what does an increase in RPP mean? - correct answer hypotension (high bp)
making heart work extra
(a-v)O2 difference increases during exercise due to _______________________. - correct answer
peripheral O2 extraction
what is VO2? - correct answer oxygen consumption
product of cardiac output and (a-v )O2 difference
depends on work intensity
VO2max - correct answer •measure of the maximal rate at which ATP is generated through
oxidative phosphorylation
•Sets the upper limit for endurance performance
-not a good predictor of performance in runners with similar VO2max values
•HRmax × SVmax × (a-v)O2 differencemax
-Gold-standard measure of cardiorespiratory fitness
-typically expressed clinically in relative (mL ∙ kg−1 ∙ min−1) terms
-Allows comparisons between individuals of different body weights
how do you do more work without consuming more oxygen? - correct answer anaerobic
respiration
relatoinship between weight and O2 - correct answer bigger people have to consume more O2
Heart Rate increases in proportion to _____________________. - correct answer exercise intensity
(work rate)
HRmax - correct answer where HR begins to plateau
relationship between HR and exercise - correct answer Before exercise, an anticipatory response
causes HR to increase above resting heart rate (RHR) due to a decrease in vagal tone and an increase
in norepinephrine and epinephrine. During submaximal exercise, HR increases linearly, leading to a
steady-state HR. This steady-state HR can be used to estimate aerobic fitness and HRmax.
HR is directly proportional to exercise
relationship between HR and VO2max - correct answer higher HR has lower VO2max because
higher intensity
,what is SV determined by? - correct answer -Venous return
-Ventricular distensibility
-Ventricular contractility
-Aortic or pulmonary artery pressure
stroke volume in response to exercise - correct answer increased SV with increased exercise
intensity up to 40 to 60% VO2max
-Beyond this, SV tends to plateau
most important determinant for VO2max
there is a plateau because you can only fit so much blood in the heart
Stroke Volume increases due to increased ___________ and increases ________________. - correct
answer venous return; contractility
what is preload? - correct answer end-diastolic ventricular stretch
what does an increase in preload lead to? - correct answer An increase in preload (i.e., increased
end-diastolic volume or EDV) leads to a stronger contraction of the heart because increased stretch
leads to greater contraction strength (Frank-Starling mechanism)
VC of inactive tissues, increased respiratory and muscle pump activities leads to increased venous
return, which helps to drive more blood back to the heart. At high exercise intensities, an increase in
HR can reduce filling time, causing a slight decrease in EDV and a plateau in SV.
What is contractility and what causes it to increase? - correct answer inherent ventricle property
norepinephrine and epinephrine lead to increased contractility
-Independent of EDV (increased ejection fraction instead)
cardiac output - correct answer The volume of blood ejected from the left side of the heart in one
minute.
HRxSV
due to increases in HR and SV
-Differences primarily due to differences in stroke volume
, increases with increased exerv=cise intensity and plateaus near VO2max
difficult to measure, so measure VO2max instead
what is the primary determinant of VO2 max? - correct answer cardiac output
Qmax - correct answer a function of body size and aerobic fitness
•70-85% of limitation in VO2max is linked to maximal cardiac output
Mean arterial pressure increases in proportion to _______________. - correct answer exercise
intensity
During endurance exercise, mean arterial pressure (MAP) increases because: - correct answer -
Systolic BP increases proportional to exercise intensity
-Diastolic BP slight decreases or slight decrease (at max exercise)
MAP - correct answer •Q x total peripheral resistance (TPR)
-Q inceases, TPR decreases slightly
-Muscle vasodilation versus sympathetic vasoconstriction in other tissues
increases in proportion to exercise intensity
Rate-pressure product (RPP) - correct answer = HR x SBP
-Important determinant of myocardial oxygen uptake and myocardial blood flow
what does it mean if bp is not increasing with more work, reducing cardiac output? - correct
answer heart is failing, blood is leaking, could be internal bleeding or ischema
what does an increase in RPP mean? - correct answer hypotension (high bp)
making heart work extra
(a-v)O2 difference increases during exercise due to _______________________. - correct answer
peripheral O2 extraction
