Reading the research honestly
The evidence supports a real physiological effect from altitude exposure within a specific elevation range, measured through hemoglobin mass and oxygen uptake, but it does not support altitude as a standalone explanation for why particular countries produce particular results. The research points to elevation as one input working alongside genetics, economy, culture and years of accumulated training, which is a less tidy story than the popular shorthand that high altitude simply equals fast runners, but it is the one the data actually backs, and it is why Iten and Addis Ababa keep appearing in the same physiology papers even though they represent two different versions of the same idea.
