Lectures 65, 69 & 70 "exercise Physiology"

Front 1

Respiratory Quotient (RQ = )

Back 1

RQ = VCO2/VO2

*RQ is the same as RER for all intents and purposes*

Front 2

RQ for glucose

Back 2

1.0

Front 3

RQ for long chain fatty acids (e.g., palmitate)

Back 3

0.7

Front 4

RQ for protein

Back 4

0.8

Front 5

caloric expenditure =

Back 5

VO2 * 5 kcal/L

Front 6

RQ (RER) for man at rest

Back 6

.83 (55% fat, 45% carbohydrate being oxidized)

Front 7

work rate vs:

*VE
*PAO2
*PaO2
*PvO2
*PvCO2
*PaCO2
*Artieral pH

Back 7

as work rate increases:

*VE increases linearly until ventilatory threshold is reached and then increases exponentially (hyperventilation)
*PAO2 remains the same
*PaO2 remains the same (PaO2 & % Hb saturation remain the same throughout exercise)
*PvO2 decreases (muscles consuming more oxygen)
*PvCO2 increases (muscles producing more CO2)
*PaCO2 decreases once ventilatory threshold is reached (due to hyperventilation)
*Artieral pH remains the same until VO2 max is reached and then decreases (due to lactic acid buildup)

Front 8

linear VE vs. work rate is due to (4)

Back 8

catecholamines (NE, Epi)

muscle & joint receptors

plasma [K] or osmolatiry

"Central Command"

Front 9

nonlinear VE vs. work rate is due to

Back 9

hyperventilation (hyperventilation reduces acidosis by blowing off CO2)

Front 10

HR max =

Back 10

HR max = 220 - age

Front 11

SV vs. work rate (VO2)

Back 11

SV increases initially with increasing work rate and then levels off at VO2 > 50% VO2 max

Front 12

HR is governed by

Back 12

SA node

Front 13

SV is determined by

Back 13

Frank-Starling

-initial heart stretch causes doubling of SV
-increasing HR means a shorter filling time causing SV to level off

Front 14

increased active muscle blood flow is due to (2)

Back 14

increased MAP

vasodilation in active muscle groups

Front 15

a-v O2 difference increases with increasing work rate due to (3)

Back 15

increased capillary perfusion (increased area and decreased thickness)

decreased myocyte PO2 (increased PaO2 -PcapO2 difference)

right shift in O2-Hb dissociation curve (Hb readily unloads O2 into active muscle due to increased temperature, PCO2 and decreased pH)

Front 16

MAP vs. work rate (VO2)

Back 16

MAP increases with increasing work rate

*in a healthy person, SBP increases while DBP remains roughly the same at every level of exercise*

Front 17

aerobic supply of ATP is from

Back 17

mitochondrial oxidation of:

-carbohydrate (major-45% at rest)
-fat (major-55% at rest)
-protein (minor-5% at rest)

Front 18

anaerobic supply of ATP (4)

Back 18

stored ATP (minor)

CP + ADP --> ATP + C (major)

ADP + ADP --> ATP + AMP

glycolysis (glycogenolysis produces glucose that can be run through glycolysis to produce ATP)

*[CP] is 3X [ATP]*

Front 19

anaerobically provided ATP is important when (2)

Back 19

transitioning from one level of activity to a higher level of activity

exercise demands exceed the anaerobic threshold of the individual (anaerobic threshold precipitates the ventilatory threshold)

Front 20

lactic acid appears in the blood when

Back 20

the anaerobic threshold has been exceeded

Front 21

anaerobic threshold for untrained vs. highly trained individual

Back 21

anaerobic threshold for untrained individual: 50% of VO2 max

anaerobic threshold for highly trained individual: 85-90% of VO2 max

Front 22

ATP levels are maintained by

Back 22

CP

*muscle ATP levels seldom drop below 70% of normal due to CP ([CP] is 3X [ATP]*

Front 23

RER vs. work rate (VO2)

Back 23

RER increases with increasing work rate (VO2)

Front 24

RER

*under steady state conditions
*under high intensity conditions

Back 24

under steady state conditions, RER >0.85 (reflects increased carbohydrate use and decreased fat use)

under high intensity condition, RER > 1.0 (reflects hyperventilation)

Front 25

RER vs. fitness level

Back 25

RER decreases with increasing fitness level (trained individual will burn more fat than untrained individual at any give level of exercise)

Front 26

carbohydrate (glucose) utilization vs. work rate (VO2)

Back 26

carbohydrate utilization increases with increasing work rate (VO2)

*although [insulin] decreases with increasing work rate, insulin sensitivity increases with increasing work rate*

Front 27

at low exercise intensities, blood ____ is a major energy substrate

Back 27

free fatty acid

Front 28

blood free fatty acid utilization vs. work rate (VO2)

Back 28

blood free fatty acid utilization decreases with increasing work rate (VO2)

Front 29

blood ____ is important in high oxidative red (slow twitch, type I) fibers

Back 29

TG

Front 30

VO2 =

Back 30

VO2 = CO * a-v O2 difference

Front 31

increase in VO2 max with training is due to (2)

Back 31

increased CO
-due to increased SV

increased a-v O2 difference
-due to more capillaries (increased area) and mitochondria (increased capacity to synthesize ATP especially from free fatty acids)

Front 32

increased mitochondrial content in response to aerobic exercise results in (3)

Back 32

increased capacity to synthesize ATP aerobically from free fatty acids

increased endurace capacity

increased reliance on fat as a metabolic fuel at any given work rate

Front 33

rate pressure product (RPP = )

Back 33

RPP = HR * SBP

Front 34

RPP measures

Back 34

myocardial oxygen need

Front 35

RPP untrained vs. trained individual

Back 35

RPP is higher in the untrained individual (higher HR and higher SBP) than in the trained individual (lower HR and lower SBP)