This is a new craze among Australian free divers and extreme sports lovers, watched by the spectators on monitors. The rules of underwater upside-down ice hockey are quite similar to the classic game. What makes it even more extreme is that the game is played under ice without oxygen in a rink 6 meters wide by 8 meters long. Each period lasts 10 minutes with a 10-minute break for divers to warm up. Players have to surface for air every 30 seconds at least.
