 Inhaling a xenon / oxygen mixture activates production of the transcription factor HIF @-@ 1 @-@ alpha , which leads to increased production of erythropoietin . 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 ( WADA ) added Xenon ( and Argon ) to the list of prohibited substances and methods , although at this time there is no reliable drug test . 
 Inhaling a xenon / oxygen mixture <a href='uninflect' title='1'><mark>activates</mark></a> production of the transcription factor HIF @-@ 1 @-@ alpha , which <a href='uninflect' title='2'><mark>leads</mark></a> to increased production of erythropoietin . The latter hormone is known to increase red blood cell production and athletes <a href='null_genetive' title='3'><mark>'</mark></a>performance . Xenon inhalation <a href='been_done' title='4'><mark>has</mark></a> been used for this purpose in Russia since at least 2004 . On August 31 2014 the World Anti Doping Agency ( WADA ) added Xenon ( and Argon ) to the list of prohibited substances and methods , although at this time <a href='dey_it' title='5'><mark>there</mark></a> is no reliable drug test . 
Inhaling a xenon / oxygen mixture activate production of da transcription factor HIF @-@ 1 @-@ alpha , which lead to increased production of erythropoietin . The latter hormone is known to increase red blood cell production and athletes  performance . Xenon inhalation done been used for this purpose in Russia since at least 2004 . On August 31 2014 the World Anti Doping Agency ( WADA ) added Xenon ( and Argon ) to tdalist of prohibited substances and methods , although at dis time it ain't no reliable drug test .