 <unk> a xenon / oxygen mixture activates production of the transcription factor <unk> @-@ 1 @-@ alpha , which leads to increased production of <unk> . The latter hormone is known to increase red blood cell production and athletes ' performance . Xenon inhalation has been used for this purpose in Russia since at least 2004 . On August 31 2014 the World Anti Doping Agency ( <unk> ) added Xenon ( and <unk> ) to the list of prohibited substances and methods , although at this time there is no reliable drug test . 
