2026 exphys exam 2 BP and cardiac output

exam 2 (3rd ppt)

what is bp?

pressure exerted by the blood agaisnt the inside of the arterial walls

what is systolic pressure ?

highest arterial pressure obtained during contraction phase (normal=120mmhg)

what is diastolic pressure?

the pressure during diastolic (relaxation) phase (normal=70-80mmgh)

the diastolic blood pressure provides an indication of what?

peripheral resistance

what are some factors that influence arterial bp?

-blood volume increases

-heart rate increases

-stroke volume increases

-blood viscosity increases

-peripheral resistance increases

(these all cause blood pressure to increase)

during the first few mins of exercise, what happens to systolic bp?

a rapid increase as a result of the increase blood return to the heart then it levels off as exercise intensity levels off

what happens to systolic bp after exercise?

there should be a quick decrease in systolic bp followed by a more gradual decrease

(could go below pre-exercise bp)

why does resistance exercise cause an increase in bp?

the sustained mm forces cause compression of the peripheral arterioles which leads to an increase in resistance to blood flow which makes the heart have to work harder to pump against it therefore greater strain = higher bp:(

during UE or LE is there a higher bp change?

UE bc smaller mm mass and smaller vasculature which offers greater resistance to blood flow

when training cardiac pts, start w LE exercise first

how much is too much as it relates to bp systolic change w exercise?

210mmhg for men and 190 mmhg for women

true or false; aerobic training has been shown to reduce both systolic ad diastolic bp

true (esp w those w hypertension)

what is myocardial oxygen utilization?

the heart relies only on aerobic reactions to get ATP to perform work

what is myocardial oxygen uptake?

the amount of oxygen the heart can use to produce atp to perform its work

what are some factors that interact w myocardial oxygen uptake

-tension development within the myocardium

-myocardial contractility

-herat rate

what is double product or the rate to pressure product (RPP)

the method to estimate the myocardial workload

with UE exercise, what it more effected than LE exercise?

HR, systolic BP, RPP, repiratory exchange ration and blood lactate concentration

aerobic capacity is ___% lower in maximal arm compared to leg exercise?

25%

at rest, how much blood circulates for both trained and untrained individual?

5 liters

true or false; oxygen carrying capacity doesnt vary w training bc hemoglobin content doesnt flunctuate

true (oxygen carrying capacity)

who require 5-10% larger cardiac output at any given submaximal oxygen uptake

teenage and adult women than males

what is oxygen extraction?

the amount of oxygen the tissues take out of the blood as blood passes through them

what happens to oxygen extraction during exercise?

mms are working harding so they need more o2 so mm extract more o2 from blood

this creates greater arterial-venous oxygen difference bc less o2 remains in the venous supply

what are some factors that affect the arterial-venous oxygen difference ?

(less o2 in veins bc exercising mms are pulling it)

1. shunting of blood to exercising mms

2. greater capillary density in specific mms trained

3. increase in individual mm cells to generate energy aerobically

what happens to cardiac output from rest to steady state?

a rapid increase followed by a more gradual increase until it plateaus as blood flow matches exercise metabolic requirements

true or false; with trained vs untrained, there is little difference in cardiac output at rest, however HR is lower and SV is higher

true there is little difference in CO at rest

how does cardiac output differ at rest in trained vs untrained individuals?th

there is little difference in CO at rest

what happens to HR and SV in trained individuals at rest?

HR is lower SV is higher

at any submaximal workload, how do HR and SV change w training?

HR decreases while SV increases

why is maximal cardiac output higher in a trained individual?

maximal cardiac output is higher due to an increased stroke volume

what happens to oxygen extraction in active mm w training?

oxygen extraction increases in active mms

recovery of heart rate and blood pressure between bouts depends on what?

-fitness level

-temperature and humidity

-duration and intensity of exercise

Venous return increases during exercise how does this come about?

-skeletal mm pump

-respiratory pump

-venoconstriction

how does this increase in venous return change SV?

sterlings law

increase in venous return→ increases ventricular filling→ increase in preload→ increase in stretch of ventricular mm→ stronger contraction→ increases SV

what happens to HR and SV during exercise?

hr increases, sv increases initially then plateaus

what is the intrinsic and extrinsic controls of the heart rate

intrinsic = inside heart (i.e SA node pacemaker)

extrinsic = outside heart (i.e sympathetic ns, valgal stimulation, hormones)

why does hr increase during exercise?

parasympathetic withdrawl, sympathetic increase, and release of catecholamines that increase hr and contractility

stopped at slid 38