Even  the  most  musclebound  bodybuilder types  get  BMI `s  in the  29-31  range  I think. Above  40..I dont  think  you could  be  over  40  and  not  be  fat.  Maybe  one  of  our  swole  shitlords/ladies  could  comment on this. Edit  found  this  http://www.true-natural-bodybuilding.com/bmi-bodybuilders.html