How do EPO and red blood cell mass respond to living high and training low?
• Increases in EPO lead to increases in red blood cell mass, but the relationship is not linear. • Peak EPO level is reached after two to three days altitude exposure and tends to gradually return to baseline after about 25 to 28 days living at altitude. • The percent increase in EPO level appears to be more important than the absolute increase in EPO in stimulating increases in red blood cells. • When athletes return to sea level, EPO level is suppressed and red blood cell mass gradually declines. • Red blood cell mass does not increase for approximately 10 days after EPO increases. • If you cannot measure EPO directly, then measuring reticulocytes (immature red blood cells) provides an indication of the EPO response. What about iron levels? • Athletes should have a blood test 6 weeks before starting altitude training. If serum ferritin is less than 30 ug/l for women or 40 ug/l for men, then increase dietary iron and supplement to increase ferritin prior to altitude exposure. Otherwis
