Finswimming

Finswimming is a high-speed underwater sport that relies on specialized equipment to move through water. While it shares some similarities with traditional sports swimming, it is defined by the use of masks, fins, and snorkels. It also incorporates underwater breathing apparatus for certain disciplines. The sport grew out of early underwater diving techniques, such as snorkeling and open-circuit scuba diving. Today, it is a regulated international sport overseen by the Confédération Mondiale des Activités Subaquatiques, also known as CMAS.

Athletes in this sport are officially referred to as swimmers under International Rules. The competition is divided into two primary environments: the swimming pool and long-distance open water. Pool competitions typically take place in Olympic-size pools, which are 50 meters long, 21 meters wide, and 1.8 meters deep. Long-distance events occur in natural water bodies like lakes, rivers, or the sea. For these open water sites, authorities must certify the water quality. Organizers also select sites with low tides and low currents to ensure safety.

There are four distinct technical disciplines used in finswimming. The first is Surface Finswimming (SF), where swimmers stay on the water's surface using a mask, a snorkel, and either a monofin or bi-fins. The second is Apnoea (AP) finswimming, which is an underwater discipline. In AP races, swimmers use a mask and a monofin while holding their breath for a 50-meter distance. The third is Immersion (IM) finswimming, also called scuba finswimming. These swimmers use a mask, a monofin, and open-circuit scuba equipment to breathe underwater.

The fourth discipline is Bi-fins (BF), often called stereo-fins. In this style, swimmers use a pair of fins and a crawl stroke while remaining on the surface. This category was introduced in 2006 to provide more opportunities for swimmers. It allows those who cannot afford a monofin to participate in competitive racing. Like surface finswimming, bi-fins races can be held in pools or in open water environments. Open water bi-fins races can reach distances of 4 km or 6 km.

The history of the sport is closely tied to the development of rubber fins in Europe during the 1930s. An Italian diving pioneer named Luigi Ferraro organized the first sea competition in 1951. By 1958, the first competition in the Soviet Union had taken place. The sport saw significant growth through the late 20th century. The first World Championships were held in Hanover, Germany, in 1976. The sport was also included in the inaugural World Games in Santa Clara, California, in 1981. The arrival of the monofin in the early 1970s changed the sport forever. It allowed swimmers to break all existing world records by the end of that decade.

Finswimming is remarkably fast compared to traditional swimming. For example, the men's 50m freestyle world record in sports swimming is 20.91 seconds. In contrast, the men's 50m apnoea world record is only 13.70 seconds. This makes finswimming roughly 50% faster than standard swimming. Because of this speed, training is very specialized. Athletes focus heavily on core stability, plyometrics, and weight training on land. They prioritize technical precision and mental preparation over the high volume of laps used in traditional swimming.

Strict rules govern the equipment used by these athletes to ensure fair play. Masks are required for eye protection and visibility, but the rules do not dictate specific mask types. However, snorkels must be center-mounted, also known as front snorkels, and must meet specific dimensions. Monofins are regulated by maximum size templates. Bi-fins must be from brands that are certified, or homologated, by CMAS. For immersion swimming, scuba cylinders are limited to a maximum pressure of 200 bar and a minimum capacity of 0.4 liters. The use of oxygen-enriched gas mixtures is strictly forbidden in these competitions.