impact of exercise and training on ventilatory pathways

Question 1

purpose

Answer 1

to carry o2 and remove co2 from all body tissues
breathe more to get co2 out rather than trying to get o2 in

Question 2

pulmonary diffusion

Answer 2

gas exchange between alveoli and capillaries
insprired air path:
- broncial tree to alveoli
blood path
- right ventricle to pulm arteries to pulm capillaroes
- capillaries surround alveoli

Question 3

heavy exercise

Answer 3

RBCS are not fully saturated with o2 due to lack of time to load them with o2
increased RBC would allow for an increased avo2 difference and have higher o2 carrying capacity and better o2 extraction

Question 4

avo2 difference

Answer 4

arterial o2 content= 20ml of o2/100ml blood
mixed venous o2 content varies - at rest is 15-15ml/100ml
avo2 diff~ 15-15ml/100ml
o2 gradeint in lumngs also increased

Question 5

example- rowing

Answer 5

rowing puts a lot of strain on the respiratory system and rowers have large static columes
vital capacity- increases with height, weight and FFM but is not affected by physical activity
exercise training doesnt change static lung volumes, larger volumes related to body size and genetic influences

Question 6

dead space ventilation

Answer 6

volume of air which is inhaled that doesnt take part in gas exchange
air that remains in the conducting airways= anatomic dead space
alveoli that are not or poorly perfused= alveolar dead space
anatomic dead space ~150ml

Question 7

breathing patterns and efficiency

Answer 7

same ventilation (l/min) but lower freq of breaths and highr tidal volume is more efficient
greater tidal volume increases vol of air reaching the alveoli per breath (dead space decreased) and lower resp volume allows more time for pulmonary diffusion to occur- allowing RBCs to be loaded with o2

Question 8

minute ventilation

Answer 8

training differences
breathing frequency is trainable so elite athletes have higher breathing frequencies and ventilation rates
more H+, more co2 in less trained - ventilation increased
working anaerobically- more H+ in system- buffering of protons increases co2 and co2 increases ventilation

Question 9

comparing athletes

Answer 9

in tidal volume and breathing frequency
tidal volume is slightly higher but max breathing freq is a lot higher in trained cyclists
in cyclicsts Ve max increases which is necessary to cover the higher o2 requirements at higher exercise intensities

Question 10

o2 cost of increased ventilation

Answer 10

hypernea
oxygen cost of hypernea is a sig fraction of the total vo2 max
greater cost of breahing at 100% vo2 max, to cover o2 cost and to breathe out co2

Question 11

resp system and performance

Answer 11

previously, resp system was not considered to be performance limiting
maximal volunatary ventilation is sig greater than ventilation at max exercise
but pul ventilation may be a limiting factor during high intesntiy exercise in highly trained athletes

Question 11

loading and unloading resp muscles

Answer 11

look at lecture

Question 11

metaboreflex

Answer 11

security system of the body causing reduced blood flow to working muscles via synpathetic vasocontricition when resp muscles are fatigued