It's blacks because they on average have more testo. Second there is whites, and the ones with the baddest genetics for muscles are Asians, but they are hella smart though. Seriously, Asians and Blacks are the complete opposite while white are in the middle. Asians = Great brains, but less testo. Blacks = Not so great brains lol, but tons of testo. The reasons why there are so many "ladyboys" that are Asian is because Asian males has more estrogen in their bodies than any other race.
However, as far as Samoans goes, I guess they're pretty similar to blacks.