Exercise at Altitude

• Barometric Pressure

  the pressure exerted by the earths atmosphere at any given point

  at sea level this is 760mmHg
• Altitude

  • as altitude increases, barometric pressure decreases
  • but the composition of air remains constant resulting in a lower partial pressure of oxygen
  • this has a detrimental effect on performance
  • above 1500m
  • only affects aerobic performers
• Diffusion Gradient

  • determines how quickly oxygen can move from one area to another
  • the larger the gradient the quicker it will move, increasing oxygen delivery & performance

  
  

  
  

  greater altitude = greater negative impact on diffusion gradient = smaller diffusion gradient
• Acute Effects of High Altitude

  • decreased pressure of oxygen in alveoli air
  • decreased diffusion gradient to capillary blood
  • decreased haemoglobin & oxygen association in blood stream
  • decreased oxygen transportation to muscle tissue
  • decreased diffusion gradient to muscle tissue
  • decreased oxygen for aerobic energy production
  • increased breathing frequency & HR, decreased blood volume & SV
  • decreased VO2 max, aerobic capacity, intensity & duration of aerobic performance before fatigue
• Overall Effects

  • breathing rate increases at rest & during exercise
  • blood volume decreases in first few hours
  • SV decrease during first few hours during sub-maximal training
  • greater demand on anaerobic energy systems, leading to lactic acid production at a lower level & earlier fatigue
• Acclimatisation

  process of gradual adaptation to a change in environment
• Acclimatisation Guidelines

  • 3-5 days for low altitude performance
  • 1-2 weeks for moderate altitude performance
  • 2+ weeks for high altitude (3,000m +)
  • 4+ weeks for extreme altitude (5,000m )
• Acclimatisation Benefits

  • EPO levels rise
  • breathing rate & ventilation stabilises
  • SV & Q reduce
  • avoids altitude sickness, head aches & poor sleep