For years, promoters of sumo have been pushing for the sport’s inclusion in the Olympic Games. To get there, the International Sumo Federation has thrown its weight behind a form of the game that would offend purists and surprise most everyone else: women’s sumo. When the International Olympic Committee declared in 1994 that single-sex sports could no longer qualify as candidates for the Games, that was enough to turn tradition that featured giant men with topknots shoving each other in a ring on its head. Since then, sumo has been coming into its own internationally as an equal opportunity sport....