Yokozuna Harumafuji on Monday condemned the recent incidents of corporal punishment that have shocked Japanese society, but insisted parents must take responsibility for ensuring their children are able to stand up for themselves.

In December, an Osaka high school student committed suicide after suffering physical violence at the hands of his basketball coach, while last month, national women's judo team head coach Ryuji Sonoda resigned from his position to take responsibility for abusing team members during practice.

Sumo has also come under the microscope over the years, with a 17-year-old wrestler dying in 2007 after being forced to undergo excess "battering" in practice. But Harumafuji, who was promoted to the sport's highest rank of yokozuna last September, believes children must be equipped to deal with bullies should the need to defend themselves arise.

"I know that there have been many incidents that have appeared on television, and it pains me in my heart to see terrible things like that," the Mongolian told an audience at the Foreign Correspondents' Club of Japan in Tokyo. "The world of sumo is a world of men and it is very tough, but when you talk about schools, I think that in every society in every nation in the world you have problems with bullying.

"Even though the world itself might be peaceful, you must be able to have children who are perhaps not so weak in order to avoid bullying. In order to avoid bullying, one very important point to take into consideration is that parents need to truly look out for their children.

"They need to teach them how to take care of themselves and perhaps that is a way to deal with children who might be bullied."