There are fundamental differences between people living at high altitude and those living at sea level. Altitude natives who’s VO2 max is almost the same as residents at sea level, have substantially higher VO2 max at altitude.
The Sherpa’s superior performance at altitude, is not explained by the capacity of their leg muscles to use oxygen, but would result from:
Training at altitude will not definitely insure that the number of red blood cells are increased. Recent studies show that living and training at altitudes of 1800m(5905 ft) for 18 days failed to increase red blood cell mass. Similarly, elite Australian athletes who slept for 8 to 11 hours per night in a high-altitude or nitrogen house for 23 nights at 3000m failed to show any increase in red blood cell production.
Failure of altitude exposure to increase the blood cell mass, would then explain why the VO2 max does not increase with continuing residence at altitude less that perhaps 2500m (8202 ft). Without an increase in oxygen supply, either at altitude or at sea level, the governor model predicts that an increase in the maximum volume output necessary to raise the VO2 max cannot occur.
Hence it is clear that exposure must be to altitudes equal or greater than 2500m if there is to be any chance that performance will improve consequent to an increased red blood cell mass.
As far as muscles are concerned, training at altitude has no magical effect; muscles respond to the relative intensity of effort, and are unable to detect whether the same training is performed at sea level or at altitude.
Authors of another study suggest, that athletes will only benefit from living or training at altitude if they fulfill three criteria:
Eyrythropoeitin (EPO)
(‘Lore of Running (4th edition) has a great deal more
about erythropoeitin and the legal upper levels of the haematocrit and
haemoglobin allowed in the blood – which seem to allow for a bit of clever
cheating – and the new methods of detecting the banned hormone. But as the use
of erythropoeitin is illegal, detail will not be of interest)
As a result of the negative results derived from studies of training at altitude, alternative options have also been evaluated. These include the use of blood cell infusions (Blood doping) or of repeated injections of the hormone erythropoeitin (both illegal).
Erythropoetin (EPO) is a hormone produced naturally by the kidney, which stimulates the production of red blood cells by the bone marrow. Erythropoeitin production is stimulated whenever the oxygen supply to the kidney is reduced. This occurs whenever the oxygen content of the blood is reduced, for example, during exposure to altitude.
Since the early 1990’s, a number of researchers have been experimenting with techniques to simulate altitude exposure in those living at sea level. Two techniques have become popular.
The first is a high-altitude (Alpine) or nitrogen house in which a low oxygen, high nitrogen gas mixture, is fed into the room in which athletes rest and sleep for between 12 and 16 hours a day. The second is a more simple tent that fits over the athlete’s bed, for use when he or she sleeps. The value of both is that the athlete sleeps at altitude but is able to train at sea-level; thus the disadvantage of a reduced training intensity at high altitude is avoided. In addition, the athletes remain in their usual living and training environment.
Training with
oxygen-enriched air (hyperoxia)
I think that this technique should be of great interest to most coaches. There is a lot of detail so it will be the subject of the next letter.