Ice swimming

Winter swimming is the activity of swimming during the winter season, typically in outdoor locations (open water swimming) or in unheated pools or lidos. In colder countries it may be synonymous with ice swimming, when the water is frozen over. This requires either breaking the ice or entering where a spring prevents the formation of ice. It may also be simulated by a pool of water at 0 °C (32 °F), the temperature at which water freezes.

In Eastern Europe and Russia winter swimming is part of the celebration of the Epiphany. Competitions for winter swimming also exist. Many winter swimmers swim with standard swimming costumes rather than with wetsuits or other thermal protection. Famous winter swimmers include Ram Barkai, Lynne Cox and Lewis Gordon Pugh.

Also, many locations in North America and Western Europe hold polar bear plunges, commonly to celebrate New Year's Day, although participants are not expected to swim and generally most do not swim.

One way that the hole is maintained at regular ice swimming places is with a pump that forces the water to circulate under the hole, preventing ice from forming. Small ice-holes can also be kept open by keeping a lid/top over the hole to prevent ice forming.

Most ice swimming places also use a specific heated "carpet" going from the locker rooms to the ice-hole, both to make walking to the hole more pleasant and for safety as otherwise the water dripping from returning swimmers would freeze and create a dangerously slippery surface to walk on.

In Finland, Northern Russia, Norway, Sweden, Denmark, Estonia, Lithuania and Latvia the ice swimming tradition has been connected with the sauna tradition. Unlike dousing, it is not seen as an ascetic or religious ritual, but a way to cool off rapidly after staying in a sauna and as a stress relief.

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