Sport is also about the spectacle for spectators.  Sport has become a branch of the entertainment business and the public demands “higher, faster, stronger” from athletes. If drug-use allows world records to be continually broken, and makes American Football players bigger and more exciting to watch, why deny the public what they want, especially if the athletes want to give it to them?  The criterion that athletes should only be applying their ‘natural abilities’ runs into trouble. The highly advanced training technologies, health programs, sports drinks, use of such things as caffeine pills, and other energy boosters seem to defeat the notion that athletes are currently applying only their 'natural abilities'. Performance enhancing drugs would not go too far beyond the current circumstances for athletes.