Altitude Exposure

Question 1

Altitude

Answer 1

How high above sea level we are

PpO2 decreases as we go higher, due to a smaller concentration gradient, so less O2 moves along it

Volume of O2 stays the same, pressure reduces

Question 2

Humidity

Answer 2

Amount of water vapour in the air

Question 3

Barometric pressure

Answer 3

The pressure exerted by the Earth’s atmosphere at any given point

Question 4

Beneficial for which athletes?

Answer 4

Endurance athletes = aerobic respiration, has benefits on the cardiovascular system

• The higher you go, the pp of O2 falls so diffusion gradient becomes smaller (volume of O2 stays the same but pressure reduces)
• As a result, the performer…
• Reduction in pp, rate of diffusion is reduced at the alveoli
• This leads to:
• Decreased saturation of haemoglobin
  = body wants to produce more haeomoglobin, = produce more red blood cells
  = carry less o2 to working muscles
  = able to carry less o2 bonded to haemoglobin
• Decreased o2 transportation to muscles

Question 5

Short-term aerobic effects of altitude

Answer 5

• breathing frequency increases to maintain O2 consumption
• Blood volume/ plasma decreases (becomes less thick) by 25% to maximise blood transportation
• Stroke volume decreases during exercise (compared to sea level)
• Aerobic capacity + VO2 max decrease impacting on the intensity + duration an athlete can perform at

Question 6

Short-term anaerobic effects of altitude

Answer 6

• as po2 falls, greater demand is placed in the anaerobic energy systems
  = increasing lactic acid production
• Anaerobic fitness is slightly enhanced at altitude e.g. power, speed + strength primarily due to the thinner air (less air resistance)

Question 7

Acclimatisation

Answer 7

athlete gradually getting used to their new environment (low PO2)

Altitude starts to have an effect at 1500m

Question 8

Benefits of acclimatisation

Answer 8

• EPO levels rise, producing more red blood cells + haemoglobin
• Breathing rate stabilises, but still higher than at sea-level
• SV + CO2 reduces compared to someone who has not acclimatised as the extraction of O2 from the atmosphere improves
• Body is more efficient
  = lungs and heart
  = use + carry more oxygen efficiently
  = perform at a higher intensity for longer
• Avoid altitude sickness; headaches, breathlessness, lack of sleep etc..

Question 9

Potential issues

Answer 9

• expensive
• Difficult to train due to lack of o2
• Difficult to get there
• Dangerous
• Not able to cope
• Lactic acid levels accumulate much easier than at sea level
• VO2 max levels gets worse before gets better
• Large increase in haemoglobin makes the blood more viscous = can less to clots = leads to heart disease

Question 10

impact on gaseous exchange

Answer 10

• decreased o2 transportation to muscles
• reduced diffusion of o2 into muscles