Do black people have an extra muscle in there legs to make them run faster?

Racial sterotypical overgeneralization. There has been some scientific theories/evidence that sprinters with ancestry to west African tribes have more fast twitch muscle fibers, however, to apply this theory generally to all blacks is ridiculous. This leads to ridiculous theories like blacks in America are more athletic because strong slaves were favored and blacks in America are less intelligent for the same reason. Its racism played out through generalizations.