In 2010 , Mosier publicly self - identified as a transgender man in a leading American gay magazine , The Advocate , after competing in his first race as male .
Mosier began competing in triathlon in 2009 as female .
In 2010 , Mosier publicly self - identified as a transgender man in a leading American gay magazine , The Advocate , after competing in Mosier 's first race as male .
Mosier began competing in triathlon in 2009 as female .