Cardiovascular system pt 5 Flashcards
What is the O2 consumption levels at rest and 100% VO2 max?
11mL/kg min
93 mL/kg min
What is the Hr at rest and 100% Vo2 max?
125 bpm
279 bpm
What is the Q at rest and 100% VO2 max?
5.2
17
What is the avO2 at rest and 100% VO2 max?
5.2
13
What is the sys BP at rest and 100% VO2 max?
139
198
What is the dia BP at rest and 100% VO2 max?
85
71
What is the MAP at rest and 100% VO2 max?
111
131
What is the SVR at rest and 100% VO2 max?
- 9
7. 9
What is the Lactate concentration at rest and 100% VO2 max?`
- 8
3. 7
Which factors increase linearly at exercise?
VO2, HR, Q, Sys BP, and MAP
Which factors increase in a curvilinearly during exercise?
SV and avO2
Which factors decrease during exercise?
SVR and Dia BP (sometimes stays the same)
Why does Hr increase?
Parasympathetic withdrawal and Sympathetic activation
What causes SV to increase during exercise?
- Preload is increased due to increased venous return and vasoconstriction
- Afterload is increase due to increased sys BP which has a neg. effect on SV
- Contractility is increased due to increased beta 1 stimulation
What limits LVEDP in the frank starling relationship?
Pericardium prevents LVEDP from increasing past a certain point. Can be stretched with exercise training
What is responsible for an increased cardiac output during mild exercise?
Increase in HR and SV
What is responsible for an increased cardiac output during hard exercise?
Mostly due to an increased HR
Why does avO2 increase during exercise?
CaO2 does not change but CvO2 goes down because more oxygen is being used in the muscles.
Why does CvO2 decrease in a curvilinear fashion?
Muscle recruitment
Capillarity of muscles
Mitochondrial density
What happens to Sys BP during exercise?
It is raised and dependent on Q
What happens to Dia BP during exercise?
It decreases and is dependent on SVR
What happens to the SVR in the kidneys and splanchnic organs during exercise?
increases
What happens to the SVR in the skeletal muscles during exercise?
It decreases
What is the most important vasodilator at the beginning of exercise?
NO
What is the most important vasodilator later in exercise?
Vasodilators especially adenosine
What is sympatholysis?
Vasodilator metabolites are released and cause vasodilation and when they come into contact with sympathetic nerves inhibit the release of NE. This reduces vasoconstriction in working muscles
What happens to muscles during exercise?
Blood flow increases
What happens to blood flow to inactive muscles and organs?
Blood flow decreases, stomach has the largest drop
What is the redistribution Q in muscles?
Rest 15% Exercise 80%
What is the redistribution of Q in the kidney?
Rest 20% Exercise 2%
What is the redistribution of Q in the splanchnic organs?
Rest 30% Exercise 3%
Why do skeletal muscles see vasodilation during exercise when there is sympathetic innervation?
Vasodilator metabolites are released during exercise and stimulate vasodilation and win out over the sympathetic innervation
What happens to NE levels as you exercise?
After reaching about 45% VO2 max it raises until it reaches 100% VO2 max. Levels of also rise the longer you exercise
Sympathetic activation is…
Intensity and duration dependent
