(4A, Ch24) Physical Activity and Altitude

Question 1

PO2 calculation formula

Answer 1

PO2 = 0.21 x pressure

Question 2

Which is increased at high altitude compared to sea level?

PaCO2 (arterial PCO2)
Hemoglobin’s saturation with oxygen
PaO2 (arterial PaO2)
PIO2 (PO2 of inspired air)
minute ventilation

Answer 2

minute ventilation

Question 3

Cardiac output and altitude

Answer 3

increases at higher altitudes rather than at sea level

Question 4

Does aerobic training at altitude improve VO2max at sea level?

Answer 4

No

Question 5

Who can benefit from training under hypoxic conditions?

Answer 5

Those training for anaerobic capacity
ex: power athletes

Question 6

As altitude increases, the percentage of oxygen in dry air….

Answer 6

remains the same

Question 7

At altitude (compared to sea level), VO2 during submaximal exercise at the same absolute workload is ….

Answer 7

the same

Question 8

Data suggest the possibility that physical activity at high altitude (compared to sea level) is ______ often above 50% of VO2max

A. more
B. less

Answer 8

more

Question 9

Qmax, HRmax, and VEmax at high altitudes are _____ as in rest

Answer 9

The same

Question 10

HR and altitude

Answer 10

increases at higher altitudes rather than at sea level

Question 11

Examples of immediate effects of high elevation on pulmonary and cardiovascular systems (2)

Answer 11

• hyperventilation
• increased submaximal HR, Q

(NOTE: stroke volume and MAX Q remain the same)

Question 12

Changes in SaO2 are least drastic with changes in altitude around…

A. 1000 meters
B. 3000 meters
C. 7000 meters

Answer 12

A. 1000 meters

(NOTE: At this altitude, the decrease in oxygen availability is minimal, and the body can maintain near-normal SaO₂ levels. At higher altitudes, the drop in SaO₂ becomes more pronounced)

Question 13

VO2 for an absolute workload (e.g. 100W)…

A. Is lower at high altitude
B. Is higher at high altitude
C. Not different at high altitude

Answer 13

C. Not different at high altitude

(NOTE: The oxygen cost of an absolute work rate is the same regardless of altitude).

Question 14

All of these athletes are hoping for a PR this weekend, but their meet has been moved from Des Moines (300 m above sea level) to Colorado Springs ( 1,800 m above sea level). Who’s least excited?

A. 5k runner
B. Long jumper
C. 100 m sprinter
D. 400 m runner

Answer 14

A. 5k runner

Question 15

Describe the lactate paradox

Answer 15

lower blood lactates achieved at altitude

Question 16

Oxygen “transport cascade” at sea level and altitude

Answer 16

Lower start in PO2 for altitude than at sea level

Question 17

What is the main reason for a drop in VO2 max at altitude?

Answer 17

Oxygen delivery to working muscle

(WHY? There is decreased SaO2 of Hb due to decreased alveolar pO2)

Question 18

In which range of PO2 is the curve fairly flat (horizontal)?

A. 50-20 mmHg
B. 80-100 mmHg

Answer 18

B. 80-100 mmHg

(NOTE: The curve plateaus out in that range; before that point, the values on the curve increase).

Question 19

Effects of acclimatization (2)

Answer 19

Increased hematocrit and blood hemoglobin content

(WHY? the kidney adapts to lower O2 concentrations and releases erythropoietin to produce more RBC).

Question 20

Lving at altitude can provide _____ regarding aerobic capacity.

A. Positive influence
B. Negative effects

Answer 20

A. Positive influence

Question 21

Hypoxic tents mimic…

Answer 21

living at altitude

Question 22

Supplemental iron _____ hematocrit response to altitude.

Answer 22

improves

Question 23

What is the relationship between VO2 max and altitude?

Answer 23

VO2 max decreases as altitude increases

Question 24

Which type of events are impaired at higher altitudes?

Answer 24

aerobic events, with the longer events taking the biggest hit

Question 25

Workout intensity at higher altitudes compared to sea levels are ...

Answer 25

lower intensity

Question 26

What is the relationship between excreted catecholamines and altitude in the first few weeks of adaptation?

Answer 26

They increase over the first week at altitude

Question 27

Examples of long term effects of high elevation on pulmonary and cardiovascular systems (6)

Answer 27

- hyperventilation - increased submaximal HR, Q - Stroke volume and Max Q decrease - Increased skeletal muscle - Increased mitochondrial density - Increased RBC

Question 28

Describe the “live high-train low” approach

Answer 28

Living at higher altitudes and training at lower altitudes

Question 29

Which is most increased during submaximal aerobic exercise at high altitude compared to sea level? A. PIO2 B. PaCO2 C. stroke volume D. a-v O2 difference E. HR

Answer 29

E. HR

Question 30

What's a possible cause of the lactate paradox?

Answer 30

May be from lower catecholamines after long-term altitude exposure

Question 31

Altitude and partial pressure of inspired air (PIO2) AKA PO2

Answer 31

As altitude increases, PIO2 decreases (NOTE: also applies to PaO2).

Question 32

Sensory and motor deficits ____ when SaO2 decreases

Answer 32

increase

Question 33

How does altitude affect VE? PaCO2?

Answer 33

- increases VE, causes PaCO2 to decrease (NOTE: With greater VE, there’s more CO2 lost in the breath, so PaCO2 goes down).

Question 34

Data suggest that average daily circulating catecholamines are... A. Higher B. Lower At high altitude compared to sea level

Answer 34

A. Higher (NOTE: Norepinephrine is higher than epinephrine).