Underwater Hockey (UWH), also known as Octopush (mainly in the United Kingdom) is a globally played limited-contact sport in which two teams compete to manoeuvre a puck across the bottom of a swimming pool into the opposing team's goal by propelling it with a hockey stick (pusher). It originated in England in 1954 when Alan Blake, a founder of the newly formed Southsea Sub-Aqua Club, invented the game he called Octopush as a means of keeping the club's members interested and active over the cold winter months when open-water diving lost its appeal. Underwater Hockey is now played worldwide, with the Confédération Mondiale des Activités Subaquatiques, abbreviated CMAS, as the world governing body. The first Underwater Hockey World Championship was held in Canada in 1980.
Underwater Hockey enjoys popularity in the United Kingdom, Australia, Canada, France, the Netherlands, New Zealand, South Africa and the United States, as well as to a lesser extent in other countries such as Argentina, Belgium, Brazil, Colombia, the Czech Republic, Germany, Hungary, Italy, Ireland, Israel, Japan, the Philippines, Poland, Portugal, Serbia, Singapore, Slovenia, Spain, Switzerland, Turkey and Zimbabwe, and is gaining a foothold in numerous additional countries.
Historically, World Championships have been held every two years since 1980. At the Confédération Mondiale des Activités Subaquatiques (CMAS) 14th World Underwater Hockey Championship held in August 2006 in Sheffield, England, at the time a record 44 teams from 17 countries competed in six age and gender categories. Participating countries were Australia, Belgium, Canada, Colombia, Hungary, France, Italy, Japan, Jersey C.I., the Netherlands, New Zealand, South Africa, Spain, Turkey, the United Kingdom, Ireland, and the United States. Subsequent world championships have been less well-attended, including the WAA World Championship held in 2008 in Durban, South Africa, until the 18th CMAS World Championship was held in Eger, Hungary in August 2013. This event once again saw all age and gender divisions, now including men and women in U19, U23, Masters and Elite categories compete. There were 68 teams competing across the eight age/gender divisions from 19 participating countries, making this World Championship the largest competition in the history of the sport to date. During 18th World Championships a decision was made by the federations to split the competition into two events with Junior Grades (U19, U23) to be accommodated in a separate to be held every two years from 2015 with the  for the Elite and Masters grades in Stellenbosch, South Africa in 2016.
At Elite level Australia are the current Men's World Champions, and [South Africa] are the current Women's World Champions. At Masters level Australia are the current Men's World Champions, and [[Australia] are the current Women's World Champions. At U23 level Turkey are the current Men's World Champions, and [[New Zealand] are the current Women's World Champions. At U19 level France are the current Men's World Champions, and [New Zealand] are the current Women's World Champions.
The next World Championships for Elite and Masters grades are due to be held in Australia in July 2020. The next World Championships for the Age Groups are due to be held in Sheffield, England in August 2019.
How does it work?
Two teams of up to ten players compete, with six players in each team in play at any one time. The remaining four players are continually substituted into play from a substitution area, which may be on deck or in the water outside the playing area, depending on tournament rules.
Before the start of play the puck is placed in the middle of the pool, and the players wait in the water whilst touching the wall above the goal they are defending. At the start-of-play signal (usually a buzzer or a gong) in-play members of both teams are free to swim anywhere in the play area and try to score by manoeuvring the puck into the opponents' goal. Players hold their breath as they dive to the bottom of the pool (a form of dynamic apnoea, as in free-diving). Play continues until either a goal is scored, when players return to their wall to start a new point, or a break in play is signalled by a referee (whether due to a foul, a time-out, or the end of the period of play).
Going for strike Games consist of two halves of typically ten to fifteen minutes and a short half-time interval of usually three minutes. At half time the two teams switch ends.
There are a number of penalties described in the official Underwater Hockey rules, ranging from the use of the stick against something (or someone) other than the puck, playing or stopping the puck with something other than the stick, and "blocking" (interposing one's self between a team-mate who possesses the puck and an opponent; one is allowed to play the puck but not merely block opponents with one's body). If the penalty is minor, referees award an advantage puck: the team that committed the foul is pushed back 3 metres (9.8 ft) from the puck, while the other team gets free possession. For major penalties such as a dangerous pass (e.g. striking an opponent's head) or intentional or repeated fouls, the referees may eject players for a specified period of time or the remainder of the game. A defender committing a serious foul sufficiently close to his own goal may be penalised by the award of a penalty shot or even a penalty goal to the fouled player's team. Since this is an underwater sport, surface spectators may be unaware of just how physical Underwater Hockey is.
Often players who are most successful in this game are strong swimmers, have a great ability to hold and recover their breath, and are able to produce great speed underwater whilst demonstrating learned skills in puck control. It is also important that they are able to work well with their team members and take full advantage of their individual skills.