Respiratory responses to exercise part 1 Flashcards
where is the respiratory center?
medulla in the brainstem
what does the respiratory centre respond to?
- variety of input from throughout the body to regulate ventilation rate
- central & peripheral influence
what is integrated regulation
the fact that no single thing controls exercise response. it is a combination of chemical (PCO2 and H+) and neural (cortical and peripheral influence) stimuli
3 phases of respiratory response to exercise
1) neurogenic, central command in cerebral cortex
2) slower exponential rise to reach steady-state
3) fine tuning of steady state exercise
is respiratory response rapid or gradual ?
rapid then gradual
True or false: respiratory activity is the limiting factor in exercise
false, it is not the limiting factor
ventilation increases ___ with O2 consumption and CO2 production
linearly
Ve/VO2 =?
ventilatory equivalent
what ratio should ventilatory equivalent maintain up to 55% VO2 max
25L per L of O2
what can affect the ventilatory equivalent ratio be affected by?
exercise mode (prone swimming decreases and running increases)
What has to rise to maintain PO2 at the alveolar level during steady-state exercise?
VA
why is the maintenance of PAO2 important?
because it represents the driving force of O2 transfer from Alveoli into the blood stream
(A-a)PO2
alveolar to arterial O2 partial pressure difference
(A-a)PO2 difference reflects what?
efficiency of O2 transfer in the lungs during exercise
true or false: steady state exercise usually causes large changes in O2 transfer efficiency in the lungs
false. there is no noticeable difference
