Japan's Olympic female judokas were beaten with bamboo swords and slapped by their coaches, officials said, weeks after a schoolboy suicide sparked debate over corporal punishment.
A 15-strong group of judokas complained to the Japanese Olympic Committee (JOC) last month that they had been subjected to physical punishment by the team's head coach.
The group, which included athletes who took part in the London Olympics, charges that head coach Ryuji Sonoda routinely abused them, slapping them in the face and hitting them with thick wooden swords like those used in the Japanese martial art of kendo.
They also complained that some were forced to compete in matches while injured, local reports said.
"We have asked the All Japan Judo Federation (AJJF) to investigate the case and improve their methods if the charges are true," a JOC official said.
AJJF head Koshi Onozawa said the Federation has admonished Sonoda and other coaches, who had admitted several of the allegations.
"We received information in late September that Mr Sonoda, the head coach of the female national team, might have been physically bullying athletes," Onozawa told a press conference in Tokyo.
"Our executive office took this seriously and questioned both him and athletes, discovering the charges were largely true," Onozawa said on Wednesday.
The AJJF told Sonoda and other coaches that they must mend their ways and "will face a harsher punishment if a similar incident happens in the future", Onozawa said.
The Kyodo News agency said Sonoda did not deny the allegations when asked by reporters.
"Until now I have been doing things the way I saw fit, but I will mend the things that need fixing," it quoted him as saying.
The case comes weeks after a Japanese high school student killed himself after repeated physical abuse from his basketball coach, an incident that has provoked a bout of national hand-wringing over the way children are disciplined.
Referring to Wednesday's claims, education and sports minister Hakubun Shimomura told reporters a re-think was required.
"It is time for Japan to change the idea that use of violence in sports including physical discipline is a valid way of coaching," he said.
Under a law dating from 1947, teachers are not permitted to physically discipline their charges, and many react with horror to the idea. However, there are no statutory penalties for teachers who do so.
Japan's education system retains many of the quasi-militaristic attitudes that were common when public schooling became widespread in the first half of the 20th century.
As with other developed countries, older generations in Japan are less likely to see anything wrong with teachers administering physical punishment to correct errant behaviour in children.
[Image via Agence France-Presse]