Long-distance swimming

Long-distance swimming is distinguished from ordinary swimming in that the distances involved are longer than are typically swum in pool competitions. When a given swim calls more on endurance than on outright speed, it is the more likely to be considered a long-distance swim. Long-distance swims, however, may take place in pools, such as ultra-long distances swum in 1997 by Grant Robinson and Kelly Driffield (24 hour swims of a 50 m-long pool, approx 100 km). Some of the better-known long-distance swims are crossings of the English Channel, Catalina Channel,Fehmarn Belt and Cook Strait.

Ultra-long distance swimming is sometimes referred to as marathon swimming. The minimum distance that constitutes a marathon swim has dramatically shortened over time. Different organizations adopt various minimum distances. The swimming marathon events at the Olympic games have a distance of 10 km.

Long-distance swims tend to fall into one of two categories: (1) swims in which the start date and start time are chosen by the individual swimmer (often called solo-swims), and (2) swims that involve a group-start.

Long-distance swimming is one of the few events wherein there are women's records that beat men's records under equal conditions.

Swim organizations, for the purposes of their record keeping, often impose other rules. FINA and International Marathon Swimming Hall of Fame do not keep records for swims that employ thermal insulating material, drag reduction fabrics, buoyancy aids, breathing apparatus, propulsion prosthetics, etc. For major channel crossings, most organizations do allow the swimmer to use outside help, an example being that the swimmer swims alongside a boat that uses sophisticated electronics and telecommunications to help the swimmer take the easiest path through surface currents and tides. Such boats can also make the challenge easier for the swimmer by blocking wind and surface chop. Such boats also carry food and hot beverages for the swimmer to consume periodically during the swim (e.g. every 20 to 30 minutes).

In another variant, some swim organizations simply have different sets of records for different equipment scenarios (e.g. wetsuit and non-wetsuit divisions), similar to the structure of free diving record keeping.

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