Document Type



Previous studies on small numbers of young men indicated that high-altitude (HA) natives experience a smaller difference in maximum oxygen consumption (V02 max) at high and low altitude (LA) than do LA natives. To examine whether this was due to genetic adaptation to hypoxia, to non-genetic long-term acclimatization, or to differences in physical fitness, a V02 max step test was applied directly and indirectly to HA Quechua men and women between the ages of 24 and 57. Fifty-one subjects lived at 4000 meters while 49 had migrated to 70 meters 5 to 32 years ago, between the ages of 8 and 37. The men were comparable in age, height, sitting height, and maximum pulse and the women in sitting height, weight and maximum pulse. Adjusting for age, weight and the significantly greater sum of skinfolds at LA the V02 max’s were 5% to 13% higher in the men at LA and from 10% to 12% lower in the women at LA than in their HA counterparts. These differences are significantly less than have been found for many LA natives at HA and LA. Genetic adaptation to HA is considered possible, but a difference in physical training especially for the women could not be excluded.