Exercise

Question 1

VO2 max =

Answer 1

max capacity for O2 consumption during exercise

Question 2

VO2 max reflects what?

Answer 2

body’s ability to transport and use O2

Question 3

Fick Principle states:

exercise capacity is dependent on body’s ability to do what?

Answer 3

ability to deliver blood and O2 to mm AND ability of tissue to extract O2 from blood

Question 4

Fick eqn

Answer 4

VO2 = oxygen consumption

oxygen consumption = CO x a-v O2 difference

a = arterial
v = venous
a-v O2 difference = ratio of arterial to venous [O2] in blood

Question 5

What is arterial oxygen content (CaO2)?

Answer 5

dissolved O2 + hemoglobin-bound O2

Question 6

Working mm demand for O2 met how?

Answer 6

↑ blood flow

Question 7

CO ↑ how in relationship to exercise intensity and O2 consumption?

Answer 7

CO ↑ directly w/ exercise intensity and O2 consumption

Question 8

HR during exercise controlled by balance of?

Answer 8

parasymp (withdrawal) and

sympathetic (activation)

Question 9

SV ↑ during exercise due to ↑ in what?

Answer 9

Preload and

Contractility

Question 10

Preload ↑ SV how?

Answer 10

↑ venous return and filling = ↑ EDV

↑ EDV = ↑ force of contraction

Question 11

Contractility ↑ SV how?

Answer 11

↑ strength of contraction = ↑ ejection fraction

Question 12

How is blood flow to working mm ↑ during exercise? (4)

Answer 12

1) heart pumps more blood
2) shunting and redistribution of blood
3) metabolic vasodilation in working mm
4) ↓ total peripheral resistance

Question 13

How does shunting ↑ blood flow to working mm?

Answer 13

more blood sent to working mm than resting mm

Question 14

How does redistribution ↑ blood flow to working mm? (3)

Answer 14

1) during mm contraction, symp vasoconstriction opens upper valves/closes lower valves
2) muscle pumps blood centrally
3) increases venous return

Question 15

How does vasodilation ↑ blood flow to working mm?

Answer 15

resting symp vasoconstriction overwhelmed by metabolic vasodilation (↑ Pco2, H+, K+, etc)

resulting in ↓total peripheral resistance

Question 16

Blood NOT redistributed from what two organs?

Answer 16

1) Brain

2) Heart

Question 17

Effect of moderate exercise on blood distribution to skin?

Answer 17

vasodilation -> cooling response

Question 18

Effect of intense exercise on blood distribution to skin?

Answer 18

vasoconstriction -> to conserve CO

Question 19

How does exercise affect O2 extraction at working mm?

Answer 19

1) extraction ↑ 3-fold
2) ↓ venous O2 content
3) ↑a-v O2 difference

Question 20

What is Dynamic Exercise?

Answer 20

activities that keep joints and muscles moving

Question 21

What is Static Exercise?

Answer 21

activity that exerts muscles at high intensities without movement of the joints
e.g. pushing against an unmovable object

Question 22

What happens to BP during dynamic exercise? (3)

Answer 22

1) systolic BP ↑ (parallel to intensity of exercise)
2) diastolic BP ↓ from ↓ vascular resistance
3) low to mod ↑ in MAP

Question 23

What happens to BP during static exercise? (5)

Answer 23

1) peripheral arterial system mechanically compressed
2) ↑ TPR, ↓ blood flow to mm
3) ↑ systolic pressure
4) ↑ diastolic pressure -> ↑ MAP
5) ↑ HR -> ↑ CO

Question 24

Sustained static exercise impedes what?

Answer 24

venous return Ѧ SV

Question 25

Training does what to VO2max?

Answer 25

increases it

Question 26

↑ CO w/ training due to ↑ in what?

Answer 26

SV:

↑ L vent compliance = ↑ filling

Question 27

↓ resting HR from training due to?

Answer 27

↑ vagal tone

↓ symp activity

Question 28

What ↓ when you no longer train?

Answer 28

↓ CO and VO2max

Question 29

What doesn’t ↓ when you no longer train?

Answer 29

HRmax