First it depends how one messures the wrist. From what i know it must be messured over the part of the forarm and this means that if some one have more muscular forearm he can be messured with biger wrist... For example if i don't squze to much the band my forarm is 8,2 inches and when i squze it i get litlebit under 8... I think that we need some oder messurments too, like head and hips for example. Also the race must be taken under considaration. Just an observation most of the heavyweight have big heads and wide hips (Foreman,Tyson or Tua for example).