Taylor- CV response to exercise

Question 1

Locomotion/exercise exerts a global stress on the cardiovascular system by rapidly increasing _____

Answer 1

metabolic demand (O2 demand to skeletal m.)

Question 2

what increases up to 5 times with exercise compared to resting level

Answer 2

cardiac output (CO)

Question 3

___% of cardiac output may go to active muscle during exercise

Answer 3

> 80%

Question 4

what 4 things happen in response to exercise

Answer 4

1. anticipation (fight or flight)
2. vasodilation
3. baroreceptor reflex
4. muscle pump

Question 5

Immediately before activity begins, a “fight or flight” response is initiated – very brief spike in sympathetic outflow

Answer 5

anticipation

Question 6

what overcomes sympathetic vasoconstriction during exercise

Answer 6

active hyperemia

Question 7

what reduces SVR in active muscle

Answer 7

vasodilation

Question 8

during exercise, there is a large-scale skeletal m. vasodilation and drop in SVR which reduces arterial pressure, how do baroreceptors respond and why

Answer 8

HR and contractility increase as does vasoconstriction—>to maintain bp (MAP)

Question 9

what increases allowing for modest but sustained increase in arterial pressure during exercise

Answer 9

the “set point”

Question 10

dynamic contraction of skeletal m. that enhances blood and lymph flow

Answer 10

muscle pump

Question 11

dynamic contraction of skeletal m. that enhances venous return to heart

Answer 11

muscle pump

Question 12

what needs to keep up with extra blood flow to the tissues

Answer 12

lymph flow

Question 13

additional feature of exercise that is released and causes vasodilation enhanced blood and lymph flow

Answer 13

histamine

Question 14

neurotransmitters released from adrenal medulla during exercise

Answer 14

Epi and NE

Question 15

Stretch and chemical receptors in active muscle signal to medulla - potentiate sympathetic drive

Answer 15

muscle reflexes

Question 16

Initially, skin vasculature constricted by ____

Answer 16

sympathetic outflow

Question 17

With sustained or intense activity, heat stress and high sympathetic outflow increase _____ to sweat glands

Answer 17

sympathetic cholinergic outflow

Question 18

effects of sympathetic cholinergic outflow

Answer 18

sweat and vasodilation

Question 19

this increases w/ exercise allowing gas exchange to meet the O2 demand

Answer 19

ventilation

Question 20

when you cross threshold from moderate to intense exercise, what happens

Answer 20

1. blood pH decreases do to increase in lactate
2. ventilation rate increases

Question 21

______ slows O2 diffusion from alveoli to arterial circulation; seriously limits O2 loading of Hb during exercise

Answer 21

lung disease

Question 22

major effect of exercise

Answer 22

CO (cardiac output) goes up and stays up

Question 23

what decreases when exercise begins allowing for O2 delivery to muscles

Answer 23

vascular resistance

Question 24

overall process of sustaining high level of sympathetic outflow and maintaining bp to perfuse organs

Answer 24

exercise

Question 25

what actually causes CO to increase:

Answer 25

1. increase in heart contractility 2. increase venous tone (vasoconctriction) 3. decrease arterial tone (vasodilation)

Question 26

VO2

Answer 26

O2 consumption

Question 27

key indicator of exercise performance

Answer 27

VO2

Question 28

VO2=

Answer 28

CO (arterial O2-venous O2)

Question 29

cardiac output where majorly increases with exercise

Answer 29

skeletal muscle

Question 30

Main thing that drives sympathetic outflow for entire duration of exercise

Answer 30

decreased systemic vascular resistance

Question 31

quick source of ATP for muscle that is depleted quickly

Answer 31

PCr (phosphocreatine)

Question 32

uses glycolysis; lactate formed; limited ATP

Answer 32

anaerobic exercise

Question 33

uses oxidative metabolism and a lot of ATP

Answer 33

aerobic exercise

Question 34

used for prolonged exercise or very light exercise

Answer 34

FA's

Question 35

effects of exercise training

Answer 35

SV increases resting HR lower maximal CO increases

Question 36

hormone produced by kidneys that increases production of RBC's

Answer 36

EPO (erythropoietin)

Question 37

used to treat anemia in people w/ severe renal disease

Answer 37

EPO

Question 38

used for doping in endurance athletes to increase O2 carrying capacity during exercise

Answer 38

EPO

Question 39

what can unmask coronary artery disease

Answer 39

exercise

Question 40

arterioles already maximally dilated, so they steal flow from other arterioles and become ischemic during exercise

Answer 40

vascular "steal" phenomenon

Question 41

to test for heart disease

Answer 41

stress test

Question 42

patient's on treadmill or stationary bike and have what monitored

Answer 42

ECG and BP

Question 43

candidates for stress test

Answer 43

known/suspected CAD heart failure, etc.

Question 44

stress test measures this; compares metabolic rate during activity to rest

Answer 44

METs

Question 45

3 additional stress tests

Answer 45

1. echocardiogram 2. nuclear stress test 3. drugs

Question 46

pathology indicated if something abnormal is found during stress test

Answer 46

positive stress test

Question 47

strongest predictor of mortality from stress test

Answer 47

very low exercise capacity (<5 METs)