No, the success of Kalenjin Kenyans in elite distance running competitions is not due to genetics. While the tall statures of many Africans may make them better runners, it is my assessment that members of the Kalenjin community are groomed from young ages to run in distance races. This is why they win so often.
The Kalenjin community of Kenya is rather small and close-knit. though its culture and traditions may also play a role in the people's interest in competing in the world races, the affinity for the sport as well as the runners' endurance necessary to win are not coincidential. Though the runners may not be immediate relatives of one another, the community from which they hale is condensed into a small region, making it entirely possible that the competitors share similar genetic makeup.
There was a documentary (Danish I think) about this, and they went through a lot of aspects, but I think the conclusion was that the thin calves probably was the main advantage. The lesser weight they have to push back and forth for each step adds up to a lot of energy savings throughout a marathon.
I could be born there, do nothing but sit around eat cheetos and play videogames all day. By that logic I could enter a race with no prior running experience and win. , , , , , , , , , , , , , , , , , ,
The Kalenjins from Kenya are believed to be talented in running by nature. They inhabit the highland area of the country of Kenya. The climatic condition in this area enables them run for long hours when they participate in the elite distance races. I believe that they are blessed and deserve to be famous.