A majority of Japanese sumo fans support a tradition that bans women from stepping on the ancient sport's raised dirt wrestling mound, according to a survey commissioned by the Japan Sumo Association and released Wednesday.

The 2,000-year-old national sport has always banned women from the ring, though the origins of the practice remain unclear. It is believed to be based on beliefs in Shinto, Japan's native religion, that women are impure.

The survey, answered by fans who watched bouts at Tokyo's Ryogoku Kokugikan, on Sept. 12, showed 54 percent said the ban should be maintained, Kyodo News agency said. Another 46 percent said the ban should be scrapped.