As Japan prepares to host the 2020 Tokyo Olympic and Paralympic Games, a number of the country's sports bodies are taking steps to prevent coaches from verbally and physically abusing athletes following a spate of high-profile cases.
These measures include guidelines telling coaches to use positive reinforcement rather than angrily reprimanding young athletes for making mistakes.
Former women's national volleyball team player Naomi Masuko founded a volleyball tournament for elementary school students in Munakata, Fukuoka Prefecture, in 2015.