13 - Exercise at Altitude

Question 1

What is barometric pressure at sea level?

Answer 1

760 mmHg

Question 2

Partial pressure of oxygen

Answer 2

• portion of P exerted by oxygen
  0.2093 x P = 159 mmHg at sea level

Question 3

What does reduced partial pressure of oxygen do?

Answer 3

limits performance

Question 4

What is Hypobaria?

Answer 4

Reduced P at altitude

Question 5

What is the result from hypobaria?

Answer 5

Hypoxia, hypoxemia

Question 6

What happens when sea level < 500m

Answer 6

No effects occur

Question 7

Low altitude (500-2000m) affects

Answer 7

• Does not affect wellbeing
• may decrease performance and can be restored by acclimation

Question 8

Moderate altitude (2000-3000m) affects

Answer 8

• affects well-being in unacclimated people
• Performance and aerobic capacity decreases (may or may not be restored by acclimation)

Question 9

High altitude (3000-5500m) affects

Answer 9

• acute mountain sickness
• decrease in performance cannot be restored by acclimation

Question 10

Extreme high altitudes (>5500m) affects

Answer 10

• severe hypoxic effects
• highest settlements: 5200 to 5800m

Question 11

Our purposes altitude

Answer 11

> 1500m

Question 12

PP of Oxygen, carbon dioxide and nitrogen

Answer 12

O = 20.93% or 0.2093
CO = 0.03% or 0.0003
N = 79.04% or 0.7904

Question 13

What affects partial pressure of oxygen in lungs, blood and tissues?

Answer 13

Affected by partial pressure of oxygen in the air

Question 14

How does temperature decrease with altitutde ascent?

Answer 14

temp decreases 1 degree per 150 m ascent

Question 15

Humidity at altitude

Answer 15

cold air holds very little water, air at altitude is very cold and dry leading to dehydration

Question 16

What happens to solar radiation at high altitudes?

Answer 16

• Increases
• UV rays travel through less atmosphere

Question 17

Pulmonary ventilation response to acute altitude exposure

Answer 17

^ immediately at rest and submaximal exercise
decreases PO2 stimulating chemoreceptors in aortic arch
- Tidal vol ^ for several hours, even days

Question 18

Hyperventilation

Answer 18

Occurs because ventilation ^ at altitude

Question 19

What is respiratory alkalosis?

Answer 19

High blood pH

Question 20

Kidney response to acute altitude exposure

Answer 20

excretes more bicarbonate to minimize blood buffering capacity and decrease blood pH

Question 21

Pulmonary diffusion

Answer 21

At rest, does not limit gas exchange with blood
- at altitude, alveolar PO2 = capillary PO2

Question 22

Oxygen transport response to acute altitude exposure

Answer 22

decrease alveolar PO2 and decrease O2 hemoglobin saturation

Question 23

Gas exchange at muscles d to acute altitude exposure

Answer 23

decreases