In light of the World Anti Doping Agency’s 2013 Code Revision process, we critically explore the applicability of two of three criteria used to determine whether a method or substance should be considered for their Prohibited List, namely its (potential) performance enhancing effects and its (potential) risk to the health of the athlete. To do so, we compare two communities of human guinea pigs: (i) individuals who make a living out of serial participation in Phase 1 pharmacology trials; and (ii) (...) elite athletes who engage in what is effectively ‘unregulated clinical research’ by using untested prohibited or non-prohibited performance enhancing substances and methods, alone or in combination. Our comparison sheds light on norms of research ethics that these practices exacerbate with respect to the concepts of multiplicity, visibility, and consistency. We argue for the need to establish a proper governance framework to increase the accountability of these unregulated research practices in order to protect the human guinea pigs in elite sports contexts, and to establish reasonable grounds for the performance enhancing effects, and the risks to the health of the athlete, of the methods and substances that might justify their inclusion on the Prohibited List. (shrink)