Lecture 8 Flashcards
Integrative Cardiovascular, and Cardiac Responses to Exercise
what are the primary transport functions of the cardiovascular system
- supply cells with O2 and nutrients
- remove products of metabolism
- heat regulation
- transport endocrine hormones
- immune functions
what is the structure (basic) of the cardiovascular system
two systems in series (pulmonary and systemic)
characteristics of the pulmonary system (3)
- low pressure
- reoxygenation
- more of a time limited system
what are the characteristics of the systemic system (4)
- high pressure
- deoxygenation
- 5 times the pressure of the pulmonary system
- far more complex than the pulmonary system
why does parallel flow occur within the systemic and pulmonary system
due to successive branching of vessels
VO2 rises linearly with …
power output
Cardiac output rises linearly with …
VO2
what is the equation of VO2
cardiac output (SV x HR) times “a-VO2 difference”
“a-VO2 difference” is the difference between the amount of oxygen that goes into your muscles and the amount that comes out of them
what are the four things that aerobic power and fitness depends on
your ability to …
- increase cardiac output (SV and HR)
- carry arterial oxygen
- redistribute blood floe to active muscles
- extract oxygen from blood in muscles
what is autorhythimicity
the heart beats by itself without nervous innovation
which ventricle is thicker and why
left ventricle is thicker, generating 5 times the pressure of the other
because the blood leaving the left ventricle must be pumped around the whole body
what is the mitochondrial density like in the heart
VERY HIGH mitochondrial density
is systole contraction or relaxation
contraction
is diastole contraction or relaxation
relaxation
during submaximal exercise what % is cardiac output lower in trained people
5-10% lower, as more efficient when trained
what % is cardiac output higher in females during submaximal exercise
5-10% higher, as less O2 per unit of blood as less Hb
will an athlete or untrained person begin exercise with a higher stroke volume
athletes = stronger and larger heart generally
what is a key factor about stretching the ventricles more to get a higher stoke volume
as the ventricle stretches more, the muscle will have a better length tension relationship so you can contract it more optimally
why are athletes able to have a lower heart rate during exercise across time
they have a higher stroke volume
during exercise what happens to sympathetic and parasympathetic activity
increased sympathetic activity on the SA node
decreased parasympathetic activity on the SA node
how does heart rate respond to exercise intensity
heart rate will increase linearly, until VO2 max as exercise intensity is increasing
why do athletes reach a similar heart rate max but at a much higher work rate as exercise intensity increases
because they have a lower HR at rest and also less HR rise as a function of absolute workrate
so therefore they reach a similar HRmax, but at a much higher work rate
what is the two equations for working out someones max HR
220 - age
or
208 - (0.7*age)
what is a major component as to why max cardiac output decreases with age
max heart rate decreases with age
- also decreased muscle quality and valve stiffness
