Published on Monday, the report includes 56 interviews with current and former athletes across at least 16 sports, as well as an online survey with 757 responses from current and former child athletes.
In the survey -- conducted between March and June this year -- more than half the respondents reported direct experiences of physical abuse when participating in sport, including 175 athletes aged 24 or younger with recent or ongoing experiences of abuse.
'Participation in sport should provide children with the joy of play, and with an opportunity for physical and mental development and growth,' the report begins.
'In Japan, however, violence and abuse are too often a part of the child athlete's experience. As a result, sport has been a cause of pain, fear, and distress for far too many Japanese children.'
READ: 48 hours that rocked the Olympics
'I Was Hit So Many Times I Can't Count'
The title of the report, 'I Was Hit So Many Times I Can't Count,' is taken from the account of an 23-year-old baseball player, who was allowed to use a pseudonym, who says he was hit by a coach and started bleeding in front of his team while playing in junior high school.
In another account, a former professional basketball player -- also pseudonymous -- says teammates were hit every day as part of her high school team in the mid-to-late 2000s and that 'the coach would pull my hair and kick me ... I was getting hit so much [on my face] that I had bruises ... drawing blood.'
The report has been released in the week that Tokyo was originally scheduled to host the Olympics before the Games were postponed to next year amid the coronavirus outbreak.
'Sport can bring benefits like health, scholarships, and careers, but too often victims of abuse experience suffering and despair,' Takuya Yamazaki, a sports lawyer on the Executive Committee of the World Players Association, was quoted as saying in a release connected to the report.
'One of the reasons why it is so hard to deal with cases of abuse is that athletes are not encouraged to have a voice.
'The difficulty is that most national federations are managed by former athletes or people in the sports industry. They are really hesitant to say something against the established coaches.'
READ: IOC pledges to work with athletes on relaxing Olympic protest policy
HRW has called for a reform of the way sport is coached in Japan, including a ban on all forms of abuse by coaches against child athletes.
The organization says in the report that reforms against violence in sport made in 2013 and 2019 failed to 'adequately or specifically address child athlete abuse, and neither are legally binding, resulting in questions about how effective they have been and will be.'
It added: 'Taking decisive action to protect child athletes will send a message to Japan's children that their health and wellbeing matter, place abusive coaches on notice that their behavior will no longer be tolerated, and serve as a model for how other countries should end child abuse in sport.'
In a statement sent to CNN, the Japan Sports Agency (JSA) said it has read the HRW report and recently exchanged views with them.
'Violence in sports instruction is not permissible,' said the statement.
'In order to eliminate it, we have taken steps such as developing a training curriculum or making a guideline for schools.
'We also think that it is very important to provide coaches with education to prevent harassment and encourage more sports organizations to comply with governance code for sports organizations.
'We would like to continue our efforts to eradicate violence in sports, referring to the content of their report.'
In April 2013, the Japan Sports Association, the Japan Sports Association for the Disabled, the All Japan High School Athletic Federation, the Nippon Junior High School Physical Culture Association, and the Japanese Olympic in April Committee (JOC), released a joint 'Declaration on the Elimination of Violence in Sports' statement.
In the declaration, the five organizations reaffirmed 'the meaning and values of sports at a time when society is struggling with the problem of violence in sports. This declaration represents our firm resolve to eliminate violence in sports in Japan.'
In a statement, the International Olympic Committee (IOC) acknowledged the report.
'Harassment and abuse [are] unfortunately part of society and also occurs within sport,' said the IOC.
'The IOC stands together with all athletes, everywhere, to state that abuse of any kind is contrary to the values of Olympism, which calls for respect for everyone in sport.
'All members of society are equal in their right to respect and dignity, just as all athletes have the right to a safe sporting environment -- one that is fair, equitable and free from all forms of harassment and abuse.'
In 2018, Japanese police reported the suspected abuse of a record 80,104 minors to child welfare authorities -- an increase of 22.4% from the previous year, and the highest number since comparable data became available in 2004.
READ: Before taking her own life, South Korean triathlete asked her mother to 'lay bare the sins' of her alleged abusers
Not just unique to Japan
Allegations of abusive training practices in sport are not just unique to Japan.
Last month, South Korean triathlete Choi Suk-hyeon took her own life at the age of 22.
Following Choi's death, her teammates on the Gyeongju City Hall Triathlon team have spoken of the 'habitual physical and verbal abuse' that they say existed in the team. A coach and a team captain have since been banned for life from the sport, denying all allegations of abuse.
Also last month, more than 120 alleged sexual abuse victims of Larry Nassar, the disgraced USA Gymnastics doctor, sent a letter to the Justice Department requesting a copy of a report on the FBI's handling of its investigation into Nassar.
The DOJ's inspector general's office said that victims and the public should rest assured that findings will be made public at the end of an investigation into the FBI's handling of the Nasser case.
Nassar was sentenced to up to 175 years in prison after hundreds of women and girls said he sexually abused them over two decades under the guise of providing medical treatment.
- Know-how in training is my unique market of fascination and know-how. A significant component to college university student accomplishment currently
- CMMS is short for Computerized Maintenance System. Chances are youll under no circumstances really want to get fearful about any with all teaching..