Yes I'm sure that helps but genetics also plays a role. Good old genetics. The touchy subject certain people refuse to acknowledge because it "hurts their feelings".
Not all African Americans live in rough urban areas. I've seen plenty of kids that look like how Mike Tyson looked at 14 and it had nothing to do with living in a rough neighborhood. Why do you think most great sprinters are from west african descent yet most great swimmers are European? Does the rough neighborhood living only work in sports on land?
Nitpicking but we are on a geography topic afterall. Most are not from West Africa. They're from Central-East Africa or "African Great Lakes" region.