LESSON 13 - control of breathing during exercise

Question 1

what are the two terms used to describe an increase in ventilation ?

Answer 1

hypernea and hyperventilation

Question 2

when do we experience hyperpnea ?

Answer 2

experience during moderate and heavy intensity exercise

Question 3

when do we experience hyperventilation ?

Answer 3

experience diring servers intensity domain

Question 4

what is hyperpnea ?

Answer 4

an increase in ventilation that is proportional to metabolic demands

Question 5

what is hyperventilation ?

Answer 5

an increase in ventilation that exceeds metabolic demands

Question 6

is it hyperpnea or hyperventilation that is an “increase in breathing rate but within your needs” ?

Answer 6

hyperpnea

Question 7

is it hyperpnea or hyperventilation that is an increase in breathing but more than needed ?

Answer 7

hyperventilation

Question 8

is it hyperpnea or hyperventilation that “blood gasses remain from normal” ?

Answer 8

hyperpnea

Question 9

is it hyperpnea or hyperventilation that “blood gases deviate from normal” ?

Answer 9

hyperventilation

Question 10

what does increase in muscle work mean for metabolism (ATP), VO2 and CO2, and Va and Ve ?

Answer 10

• increase in metabolism (ATP)
• increase in VO2 and CO2
• increase in Va and Ve

Question 11

when are we utilizing more VO2 and producing more CO2 ?

Answer 11

during increased exercise / muscle work

Question 12

why do we breath during exercise ?

Answer 12

• CO2 produced must be cleared
• O2 extracted by the muscles from blood must be replenished

Question 13

why must CO2 produced be cleared during exercise ?

Answer 13

to prevent arterial PCO2 and H+ from rising

Question 14

why must O2 extracted by the muscles from blood be replenished during exercise ?

Answer 14

to prevent arterial PO2 from falling

Question 15

a rise in CO2 is associated with a rise in ___ ions or a __________ in pH levels (acidosis)

Answer 15

• H+
• reduction

Question 16

what happens if there is too much H+ ions or CO2 ?

Answer 16

becomes more acidic / acidosis

Question 17

PaO2 ≈ (approx. equal to) Va / O2

Answer 17

replenish oxygen

Question 18

PaCO2 ≈ (approx. equal to) CO2 / Va

Answer 18

prevent CO2 retention

Question 19

Which of PaCO2 or PaO2 should be regulated most tightly ?

Answer 19

PaCO2

Question 20

why should PaCO2 be tightly regulated over PaO2 ?

Answer 20

large changes in PaO2 at lungs dont effect O2 saturation drastically, but even small changes in PaCO2 can greatly impact pH

Question 21

can the body handle acidosis well ?

Answer 21

no, it doesnt handle acidosis well, must maintain H+

Question 22

what happens if we do not regulate arterial CO2 tightly ?

Answer 22

cause an increase in H+ ions concentration

Question 23

what is the “most important equation for alveolar ventilation”

Answer 23

Va = CO2 / PaCO2

Question 24

VT (tidal volume) x BF (breathing frequency) is the equation for what ?

Answer 24

Ve

Question 25

CO2 / PaCO2 is the equation for what ?

Answer 25

Va

Question 26

what are the two ways to increase ventilation :

Answer 26

• take more frequent breaths
• increase depth/volume of each breath

Question 27

as exercise intensity increases, what happens with Va ?

Answer 27

Va increases with our minute ventilation

Question 28

Va (alveolar ventilation) + dead space ventilation =

Answer 28

ventilation

Question 29

if you have more CO2 does that mean you’re breathing out more or less CO2 ?

Answer 29

more CO2

Question 30

hyperventilation = breathing more… what does this cause for CO2 ?

Answer 30

causes CO2 to fall

Question 31

what are the three controlling exercise hyperpnea ?

Answer 31

• neural feed-foward
• neural feedback
• humoral feedback

Question 32

which feedback is associated with “medulla and above, intrinsic oscillator” ?

Answer 32

neural feed-foward

Question 33

which feedback is associated with muscles ?

Answer 33

neural feedback

Question 34

which feedback is associated with chemoreceptors ?

Answer 34

humeral feedback

Question 35

if issues with one mechanism can the others compensate ?

Answer 35

yes

Question 36

the supra medullary inputs is associated with what ?

Answer 36

neural feed-toward

Question 37

medullary ISK (H+) chemoreceptors is associated with what ?

Answer 37

humoral feedback

Question 38

describe central chemo receptors :

Answer 38

• very responsible to changes in H+ ion concentration
• increase respiratory output with H+ ion concentration rises or pH falls
• become more acidic

Question 39

mechanic /metaboreceptors afferents is associated with what ?

Answer 39

neural feedback

Question 40

which mechanism is located with arteries / our circulatory system ?

Answer 40

humeral feedback

Question 41

what study was an example of a case that showed that central command or those neural feedback mechanisms might not be important in driving or controlling breathing during exercise ?

Answer 41

the neural and humeral factors electrically induced dog experiment 1963

Question 42

what study was an example of a case that showed the opposite experiment to the dog experiment (feedforward factors) ?

Answer 42

cat with all sensory afferent signal removed

Question 43

describe the “blocking neural input from muscle in humans” experiment :

Answer 43

• placebo and fentanyl
• blocking inputs from muscles (potentially drive a ventilation response)
• fentanyl injection in lumbar selectively blocks all afferent signals arising from skeletal muscle

Question 44

FILL IN THE BLANK :

we need Va increase in proportion to ___ in order to maintain arterial CO2, which we know is incredibly important if we allow arterial CO2 to rise…

Answer 44

VCO2

Question 45

CO2 / PaCO2 =

Answer 45

Va