Cosmetic doping--when anabolic-androgenic steroids are not enough.

Doping is considered to be a major sports problem. This article describes a new threat and challenge to the sport of bodybuilding; the nonmedical use of a chemical in order to mimic muscle hypertrophy. Although muscle fillers are not new, being used for cosmetic purposes in medicine for a long time, the illegal use of muscle fillers has been increasing during the last few years and decades. The history of cosmetic doping, with particular attention to the Brazilian case, is discussed. Limitations are noted and future needed research is suggested.