Originally Posted by brilsmurf

here is a MD speaking

what he says IS true, black swimmers are always slower than causcasian ones and this has to do with the bone density in their head: black skulls weigh more than white skulls, so they have to do more effort in keeping their head up in swimming competition, resulting in a lower speed.
This fact is being used in the identification of human remains to determine if it was a white or black person (including the pronation of teeth,..)

anymore questions: i will be happy to answer them