For most people, given all the haring around that it involves, regular soccer poses enough of a fitness challenge. Back in the 90s, however, some extreme Scandinavians decided to push the envelope and play the beautiful game amid sludgy bogland.

Welcome to the squelchy, messy world of swamp soccer.

There is just no denying it – swamp soccer is murder, like rock climbing in a suit of armor. Thank those wacky Finns, who are also responsible for the wife-carrying championship and a mobile phone throwing championship, among other bizarre contests.

Swamp soccer originally served as an exercise activity for Finnish athletes and soldiers. The Scandinavian stalwarts played swamp soccer precisely because trying to be Pele while stomping about a squashy bog is incredibly tough. To be any good, you need buckets of adrenaline and stamina.

The over-the-top, oddball training activity blossomed into a sport in 1998 when 13 teams formed and competed in a championship match in Finland, marshalled by Swamp Baron Jyrki Vaananen. Now, globally, over 200 teams play. In addition to Finland, the sport unfolds everywhere from Scotland and Sweden to Brazil.

Swamp soccer consists of two halves of 12 minutes or so. Each team has a maximum of 12 players. Players end up caked in muck from head to foot, which is uncomfortable, but good for the skin. Anyone can play whatever their size, it is said. Hard graft and a large team are key to success. The game is partly played for laughs, teams have names like Diggers Dirty Half Dozen, Mudmunchers, Bruce’s Bogtrotters, Mudchesthair United and Dirty Tackle, but it makes you incredibly fit. If it’s good enough for Finnish cross-country skiers and soldiers, it’s good enough for anyone and a tonne of fun.

Thankfully, players do not need to contend with gators – now that would be extreme.

The 2012 Swamp Soccer World Cup will be held between 23 and 24 June in Inverness, Scotland.