Between the cold, the brawls and the literal blades strapped to players feet, ice hockey is already a pretty extreme sport. But what if you were to take it one step further? Welcome to underwater ice hockey, where players have to freedive into frozen over lakes and play hockey with a floating puck against the underwater surface of the ice.
While it feels pretty cold here in Australia right now, it has to be even colder to play underwater ice hockey, usually staged when the temperature is around -5 degrees Celsius. Unsurprisingly, it's a sport pioneered by the northernmost regions of Europe - and dominated by them.
The sport is mostly based on regular ice hockey, with a couple of (fairly obvious) main differences. The rink is far smaller than a traditional ice hockey rink - usually only around 6 meters wide by 8 meters long. The goals are anchored upside down underneath the ice on each end.
With the smaller rink also comes fewer players, but a full team is still needed as players must swap out every 30 to 60 seconds to catch their breath. No underwater breathing aparatus is used during 'official' underwater ice hockey matches (though some play with tanks for fun). Because of the temperature of the water, players must stay very active to keep warm so matches can get very intense.
Four referees with scuba tanks keep track of the match from under the water, and there are usually plenty of support crew, as well as spectators above the ice. You can see the usual setup of a match in this video:
Unsurprisingly the sport hasn't been around for too long, only conceived in 2005 by free diver Christian Redl and his training partner Jaromir Foukal. Only a few years later the first ever Underwater Ice Hockey World Championship was played in 2007 at Weissensee, Austria, a location with the optimum amount of ice for the sport to be played safely.
The competing countries were Austria Czech Republic, Finland, Germany, the Netherlands, Poland, Slovakia and Slovenia, with Finland taking out the overall championship. Austria won the next championship, played in 2013.
Underwater ice hockey isn't a sport we're likely to be adopting in Australia anytime soon, but it's a great reminder of all the weird and wacky things humans put themselves through in the name of sport.
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