At the World Cross Country Championships in 1998, arguably the most competitive running event in the world, each country was limited to six entries. After all, it's conventional science that different body types have evolved in response to differing environmental conditions in different regions of the world. Fascination about black physicality and black anger about being caricatured as lesser human beings have been part of the unspoken side of the American dialogue on race for hundreds of years. The fear is that some might conclude that if blacks are faster on average, they must, as part of zero-sum reasoning, be weaker mentally. But that's a conclusion not supported by science.
Race is a term soaked in much folkloric nonsense.
The concept of race is somewhat akin to a sloppy Joe masquerading as a hamburger. Why We Are Afraid to Talk About It, they can leave misconceptions. Many traits are correlated, such as dark skin colour and the presence of the sickle cell gene. But such links are not absolute. Blacks who have evolved in cooler climates are no more likely to contract sickle cell than are non-blacks.