Term
| What are some cardiovascular adaptions resulting from endurance training? |
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Definition
Decrease in HR, BP, MAP, and CO at rest and submax exercise.
Increase in SV, a-v O2, Bld vol at rest and submax exercise
At max exercise SV, a-v O2, CO, Vo2 and bld flow all increase |
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Term
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Definition
Vo2 max is higher for LE bc there are larger muscles compared to UE
At the same VO2 HR and BP are less for LE exercise |
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Term
| What are some cardiovascular adjustment to UE exercise? |
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Definition
VO2 and HR are higher for any given workload. Lower mechanical efficencey, trunk stabilization.
HR effect may be due to greater input from peripheral receptors- Increase sympathetci stim
BP is higher for a given % VO2 max, smaller muscle mass & vasculature offer greater resistance to flow |
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Term
| What is the relationship between Rate pressure product and exercise? |
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Definition
RPP measure the work of the heart HR*BP.
Exercsie is prescribed according to RPP in pts with angina |
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Term
| What happens to the a-v O2 during exercsie and why? |
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Definition
| Difference increases as VO2 increase bc muscles are using more O2. The arterial O2 stays stable and the venous decreases bc the muscles are using more O2 |
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Term
| What is the FIck equation? |
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Definition
VO2= CO*(a-v)O2
Responds to a change in the tissues metabolic need |
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Term
| What does the change in a-v O2 during exercise depend on? 6 things |
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Definition
1) ability of mitochondria to use O2
2) Rate of diffusion into cells
3)Perfusion to working muscles
4) Type of muscle fiber being used
5)O2-Hb dissociation curve
6) Presensce of functional myyglobin |
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Term
| What are some BP effects during exercise? 3 things |
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Definition
Decrease TPR (vasodiliation to working muscles driven by autoregulation)
Increases CO which leads to increase BP
Inc. SBP (little change in DBP) |
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Term
| What does autoregulation effect during the redistribution of blood during exercise? |
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Definition
Response to the tissues metabolic state
-Precpillary sphincters and small arteries
-vasodilation, hypoxemia, temp, CO2, pH, adenosine, Mg, K, nirtic oxide |
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Term
| What does the sympathetic tone during redistibution of blood during exercise effect? |
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Definition
arteries, arterioles, precapillary sphincters
adrenergic tone- vasoconstriction (norepi)
cholinergic tone- vasodilation
slave to autoregulation |
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Term
| What are the 3 mechanisms responsible for redistrubuting blood flow during exercise? |
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Definition
Sympathetic tone
Autoregulation
hormonal control (minor role) |
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Term
| How does the blood flow get redistrubuted during exercise? (2) |
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Definition
Change in vessel diameter- decrease in gut, increase in working muscles
Recruitment of closed vessels- 1 in 30 capillaries in muscles is open at rest |
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Term
| What are the chain of events in cardiovascular drift? 5 major |
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Definition
Inc temp
cutaneous diliation-- inc bld to skin
decr plasma vol- decr SV leads to inc temp- leads to dehydration
decr SV
Incr HR to maintain CO |
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Term
| What is cardiovascular drift? |
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Definition
AN incr in HR to compensate for a decr SV to maintain CO
Usually gradual incr |
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Term
| What controls SV during exercise? |
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Definition
Incr SV up to 40-50% VO2 max, greatest incr during transition from rest to moderate exercise
Due to -- incr preload and incr contratility (EF)
SV plateaus c Incr VO2- Incr CO due to HR |
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Term
| What is the anticipatory response in the control of HR during exercise? |
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Definition
Inc HR due to psychological anticipation of the need for an incr in HR and CO
Incr sympathectic and Decr parasymp tone
Greatest in short, high intensity events |
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Term
| How does periferal input help control HR during exercise? |
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Definition
Joints and muscles
In the vessesl baroreceptors and mechanoreceptors detect movement. Inhibit sympathectic tone which decr HR and incr vasodilation |
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Term
| What 2 things control HR during exercise? |
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Definition
| Peripheral input and anticipatory reponse |
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Term
| What 2 things control HR during exercise? |
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Definition
| Peripheral input and anticipatory reponse |
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Term
| What is the relationship between HR and VO2 ? |
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Definition
Linear relationship
Incr HR as VO2 incr |
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Term
| What are 4 hings the cardiovascular system does in response to exercise? |
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Definition
Incr CO = HR + SV
Redisribution of bld flow
Incr BP
Incr a-v O2 |
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Term
| How does skeletal muscle and cardiac muscle affect contractility? |
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Definition
Incr # of motor units to incr force- skeletal
cardiac- incr force by incr contractility |
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Term
| What are 3 factors of contractility? |
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Definition
Inotrophic capacity
Incr CO 15-20%
Sympathectic control - Ince contractility |
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Term
| How does bld viscosity affect afterload? |
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Definition
| indirecty incr by incr resistance |
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Term
| What 6 things are related to/ affect afterload? |
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Definition
MAP
SV & afterload have an inverse relationship
vessel diameter
hormones epi/norepi
bld viscosity
HTN |
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Term
| How does vessel diameter affect afterload? |
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Definition
FLow = chnage in pressure/resistance
R= 8ln/r4
creates afterflow |
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Term
| how are SV and afterload related? |
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Definition
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Term
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Definition
| Pressure the ventricles have to overcome to create flow |
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Term
| How does posture affect preload? |
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Definition
| Increases venous return in the horizontal position |
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Term
| What is the Frank-Starling law of the heart? |
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Definition
| The more bld in the ventricle themore bld is expelled from the ventricle-- the more venous return the more pumped out |
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Term
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Definition
| Volume of bld in the heart pror to systole |
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Term
| What 3 things is SV dependent on? |
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Definition
| Preload, afterload and contractility of the heart |
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Term
| How does R atrial pressure affect HR? |
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Definition
Incr RA pressure leads to Incr sympathectic output-- incr HR and CO
Incr atrial pressure when incr in bld back to heart |
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Term
| How do changes in BP affect HR? |
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Definition
detected in carotid and aortic arch
Incr BP- incr parasympathetic -dec HR and CO
Decr BP- Incr HR |
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Term
| How does body temp affect HR? |
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Definition
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Term
| How do the catecholamines affect HR? |
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Definition
stimulate beta receptors to incr HR- epi
Alpha receptors decr HR- epi & norepi |
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Term
| Sympathetic input on HR- normally and during exercise |
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Definition
norm- incr HR, Incr contractility
during exercise- Incr sympathectic to incr HR |
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Term
| Parasympathectic input on HR normally and During exercise |
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Definition
Norm- HR Decr
During exercise- parasymp decr to incr HR |
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Term
| What 7 things is HR dependent on ? |
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Definition
| sympathectic, parasympathetic, catecholamines, body temp, changes in BP, R atrial pressure, and age effect |
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Term
| What 2 things make up CO? |
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Definition
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