All,
There is this debate on whether or not Kalenjins have a natural advantage (gift) in running marathons (since most world records have been held by Kalenjin athletes).
I personally do not think that Kalenjins are born with natural advantage in long distance running. I believe that they practice a lot from young age (just go to Iten for example and see..) and that’s why they have perfected their craft in long distance running. This opinion also applies to Brazilian soccer—soccer is hugely loved in Brazil. Kids practice soccer from young age… the govt supports soccer, soccer stars are idols in Brazil, soccer athletes are mentors to kids. The end result is that Brazil produces some of the best soccer athletes the world has ever seen- they live and breath soccer in Brazil. African-Americans and basketball is the same. Most AA kids practice basketball at very young age, AA idols are people like Kobe, MJ, Lebron, etc. In the end, we have some of the best basketball players being African Americans.
Kalenjin success in long distance running has little to do with natural talents, climate, geographic elevation, etc-- it is about discipline, work-ethic, the love of the game and mentorship.
That’s just my opinion.