A lot of muscle with very little fat is a good combination to have when you find yourself on a dog playground, full of young male canines trying to establish dominance.  At 82 lean pounds, Ari has been one of the largest inhabitants of this playground, able to match in size and power most of the dogs there. Even Sisco (another Rhodesian, 14 months and well over 90 lbs), although clearly more mature then Ari, is not THAT MUCH bigger.