Wow, this is a strange topic. Honestly it depends on which part of Africa someone is decended from. If they're from say, Kenya, they naturally have longer, thinner legs made for running and their lungs have a larger capacity due to the higher altitude's their ancestors lived in. As far as the African Americans now, some have increased athletic ability due to their heritage, but for the most part it's due to their american culture, ie the steryotype that African Americans spend most of their time playing sports and are generally better at sports. Because of this, they actually do spend most of their time with sports and because they practice more, are therefor superior in the field to most other races.