From 65438 to 0935, the world economy was in the Great Depression. Leo Salce, a man in Chicago, USA, found that exciting dance can make a fortune on the dance floor, so he had a brainwave and launched a sensational marathon dance competition, from which Salce made a fortune. He was hungry, and then he came up with a new trick of "four-wheel roller skating competition", which really made a lot of money. This is a cruel and violent game. Both sides wear roller skates to prevent each other from passing on the court. They can scratch, bump, lift, bite, punch and kick, which is worse than boxing. This sport was boycotted by upright athletes from the beginning and was excluded from the orthodox games.
Later, some athletes reformed the sport, abandoned its violence, carried forward its advantages and formed a unique style of roller skating. 1960, the United States set off a roller skating craze. Since then, the sport has spread all over the world.