Altitude and exercise

Question 1

The alveolar arterial pO2 difference during exercise at altitude is increased due to

Answer 1

diffusion limitation

Question 2

There is a diffusion limitation during exercise at limitation due to

Answer 2

there is reduced transient time due to exercise and RBC needing longer time to pick up O2 because less O2 to pick up. moreover blood goes through lungs quicker during exercise so blood leaves desaturated

Question 3

Why is there a decrease in CO at increased altitude

Answer 3

It would not be beneficial to increase CO when there is less O2 because that would worsen transient time so blood would leave more desaturated

Question 4

The decrease of VO2 max due to a decrease in CO due to a diffusion limitation reduces …

Answer 4

exercise capacity at altitude

Question 5

VO2 for given workload is ____ at altitude and sea

Answer 5

same

Question 6

possible explanation for ventilation not reaching same levels at moderate altitude at extreme altitude

Answer 6

• max workload/exertion reached is a lot less than it is at lower altitudes
• availability of O2 supply to respiratory muscles is reduced, greater altitudes with same ventilation at moderate altitudes compromised O2 available for ventilation muscles

Question 7

breathing O2 at high altitude improves exercise capacity and reduces ventilation but doesn’t match sea level is due to

Answer 7

residual increased carotid body chemoreceptors sensitivity

Question 8

responders who ventilate more are advantageous at altitude due to

Answer 8

having more effective ventilation and better saturation of blood which means more O2 to supply exercising muscle and they have less acute mountain sickness and sleep better

Question 9

helium reduces resistance in airways which

Answer 9

makes workload of respiratory muscles easier

Question 10

metabolic cost of respiratory muscles

Answer 10

a key component to how much exercise we can undertake at altitude - more to it than ventilation