Many coaches and athletes are convinced that altitude training gives them an edge over their sea-level trained competitors. According to legendary distance Joe Vigil, "Since 1968, 95% of all Olympic and World Championship medals from the 800 through the Marathon were won by athletes who lived or trained at altitude...It can therefore be concluded that altitude training is necessary for success in endurance events." Renowned Nike Oregon Project coach Alberto Salazar has his athletes (including Kara Goucher who recently set the American record for the half marathon) sleeping at altitude using simulation equipment and tents.
At altitude, the body adapts by increasing red blood cells and hemoglobin, stimulated by higher levels of EPO. Logically this should give endurance athletes an edge.
Not everyone agrees. Athletes training in Madison, Wisconsin such as 2-mile American record holder Matt Tegenkamp and Chris Solinsky (5 time NCAA champ) train and sleep exclusively at sea level.
Owen Anderson, PhD, a leading expert on endurance training and performance, does not think altitude training helps. Anderson writes in this article published at runnersweb.com, "Overall, VO2max dropped by around 6.3 percent for each 1000-foot increase in altitude (above the baseline of 1000 feet). As VO2max declines, workouts at high-quality paces become much-more difficult to handle."
You would think that science would have this figured out by now. Stay tuned!