Ryūichi Yamamoto (山本 龍一, Yamamoto Ryūichi, born May 8, 1984), known by his shikona Yamamotoyama Ryūta (山本山 龍太), or simply Yama, is a Japanese retired sumo wrestler from the city of Saitama in Saitama Prefecture. He made his professional debut in January 2007, and reached the top makuuchi division in January 2009. His highest rank was maegashira 9. At 265 kg (584 lb), Yamamotoyama is the heaviest Japanese-born sumo wrestler in history, and is also thought to be the heaviest Japanese person ever. In April 2011, he was told to retire by the Japan Sumo Association after he and several other wrestlers were found to be involved in match-fixing. He currently resides in Los Angeles and participates in sumo exhibitions and amateur tournaments, and has made a number of appearances in television show