The Stress of Altitude

• Outline the effects of increasingly higher altitudes on (1) partial pressure of oxygen in ambient air, (2) oxygen saturation of hemoglobin in pulmonary capillaries, and (3) V O2max • Describe and quantify the oxygen transport cascade at sea level and at 4300 m • Discuss immediate and longer-term physiologic adjustments to altitude exposure • Give symptoms, possible causes, and treatment for acute mountain sickness, high-altitude pulmonary edema, and high-altitude cerebral edema • Describe the “lactate paradox” and possible causes for its occurrence • Summarize factors that affect the time course for altitude acclimatization • Graph the relation between the decrease in V O2max (% sea-level value) with increasing altitude or simulated altitude exposure • Discuss alterations in circulatory function that offset the benefits of altitude acclimatization on oxygen transport capacity • Discuss whether altitude training produces greater improvement than sea-level training on sea-level exercise performance • Describe the training concept “living high, training low” 24 C H A P T E R