To imply that there is a genetic component to any difference between human populations is racist. Jamaicans are fast because they drink natural island-grown juices. Listening to Bob Marley also helps to increase foot speed, though it is difficult to quantify.

I lived in Jamaica for two years. When I arrived I was slow afoot, but after 2 years of Jamaican herbs, juices and reggae, I increased my 100 meter time from 12.0 seconds to 10.6 seconds. Returning to the states I have been able to take advantage of my new physical prowess by running down taxi cabs and slam dunking.

Further, being born outside of marriage increases the incentive for Jamaican children to be speedy. 80% of Jamaican children are born to single mothers, who teach their children to sprint from poor dads to sugar daddies. Hoping to sire an Olympic athlete, I fathered two kids (from two different women) without incurring the financial/social obligation to rear them properly. I bet you those kids will be fast!

I blame my slowness on Bob Marley.