Aerobic exercise capacity at sea level and at altitude in Kenyan XXXX , junior and senior runners compared with Scandinavian runners.

@entity1 @entity26 @entity880 @entity3265
The aim of this study was to characterize Kenyan runners in regard to their @entity26 uptake and blood and @entity3265 responses when running. Untrained Kenyan @entity1 (14.2 +/- 0.2 years) and Scandinavian runners were included for comparison. The studies were performed at altitude (approximately 2.000 m.a.s.l.) and, for several Kenyan and Scandinavian runners, at sea level as well. At altitude sedentary adolescent Kenyan @entity1 had a mean maximal @entity26 uptake (VO2max) of 47 (44-51) ml.kg-1.min-1, whereas similarly aged @entity1 regularly walking or running but not training for competition reached above 62 (58-71) ml.kg-1.min-1 in VO2max. Kenyan runners in active training had 68 +/- 1.4 ml.kg-1.min-1 at altitude and 79.9 +/- 1.4 ml.kg-1.min-1 at sea level, with individuals reaching 85 ml.kg-1.min-1. The best Scandinavian runners were not significantly different from the Kenyan runners in VO2max both at altitude and at sea level, but none of the Scandinavians reached as high individual values as observed for some Kenyan runners. The running efficiency, determined as the @entity26 cost at a given running speed, was less in the Kenyan runners, and the difference became more pronounced when body weight was expressed in ml.kg-0.75 min-1. Blood @entity880 concentration was in general lower in the Kenyan than in the Scandinavian runners, and the Kenyans also had extremely low @entity3265 accumulation in the blood even at very high exercise intensities. It is concluded that it is the physical activity during childhood, combined with intense training as teenagers that brings about the high VO2max observed in some Kenyan runners. Their high aerobic capacity, as well as their good running economy, makes them such superior runners. In addition, their low blood lactate and @entity3265 accumulation in blood when running may also be contributing factors.
