Constant weight bi-fins, denoted by the acronym CWTB in competition notation, is a competitive freediving discipline wherein the freediver wears a pair of bi-fins (or stereo, as opposed to a monofin) to descend along the line with or without the use of their arms. Pulling on the rope or changing ballast will result in disqualification; only a single hold of the rope is allowed in order to turn and stop the descent and start the ascent. The diver is prohibited from using a dolphin kick; doing so will result in disqualification of the day's dive. [1]
For AIDA International officiated freediving competitions, bi-fins was previously included under the umbrella term of constant weight (CWT) in competition. Prior to 2019, competitors wanting to use bi-fins in competition would compete under the category of constant weight alongside those using a monofin. In 2019, AIDA formally separated Constant Weight Apnea with Bi-fins (CWTB) into its own category for competition. [2] [1] Following the rule changes, national record and world record titles could now be earned for the category of CWTB. [3]
For CMAS officiated freediving competitions, bi-fins has been recognized as a competitive category separate to constant weight (with a monofin), with officiated records for bi-fins starting as early as 2015. [4]
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Freediving, free-diving, free diving, breath-hold diving, or skin diving, is a mode of underwater diving that relies on breath-holding until resurfacing rather than the use of breathing apparatus such as scuba gear.
Natalia Vadimovna Molchanova was a Russian champion freediver, multiple world record holder, and the former president of the Russian Free Dive Federation. Described as "possibly the world’s greatest freediver," Molchanova set an unparalleled standard in the sport. She believed, “Freediving is not only a sport, it is a way to understand who you are,” reflecting her deep connection to the sport. Throughout her career, she achieved 42 world records and earned 22 world championship medals, 19 of which were gold.
Association Internationale pour le Développement de l'Apnée (AIDA) is a worldwide rule- and record-keeping body for competitive breath holding events, also known as freediving. It sets standards for safety, comparability of Official World Record attempts and freedive education. AIDA International is the parent organization for national clubs of the same name. AIDA World Championships are periodically held.
Herbert Nitsch is an Austrian freediver, the current freediving world record champion, and "the deepest man on earth" having dived to a depth of 253.2 meters.
Free immersion (FIM) is an AIDA International freediving discipline in which the freediver dives under water without the use of propulsion equipment, but only by pulling on the rope during descent and ascent.
Constant weight (CWT) is a freediving discipline recognised by AIDA, the International Association for the Development of Apnea, in which the freediver descends and ascends using their monofin and/or with the use of their arms without pulling on the rope or changing their ballast; only a single hold of the rope to stop the descent and start the ascent is allowed. Constant weight is one of the eight disciplines considered for international competition, the others being constant weight bi-fins (CWTB), constant weight without fins (CNF), static apnea (STA), dynamic apnea without fins (DNF), dynamic with fins (DYN), free immersion (FIM), and dynamic apnea bi-fins (DYNB).
William Trubridge is a New Zealand world champion and world record holding freediver.
Constant weight without fins (CNF) is an AIDA International freediving discipline in which the freediver descends and ascends by swimming without the use of fins or without pulling on the rope or changing his or her ballast; only a single hold of the rope to stop the descent and to start the ascent is allowed. Constant weight without fins is the depth discipline of freediving that is most challenging, because of the physical effort needed to swim without assistance.
Dynamic apnea is a discipline of competitive freediving, also known as competitive apnea. Dynamic apnea covers two of the eight competitive freediving categories recognised by the AIDA International : dynamic with fins (DYN) and dynamic without fins (DNF). Both disciplines require breath held dives where the diver travels in a horizontal position under water under their own power without aid/physical contact of a static surface, with the exception of the pool wall when done indoors. The records can only be recognized in pools of 25m or greater.
Vertical Blue is a invite-only elite freediving competition which has been held in The Bahamas at Dean's Blue Hole by freediving world record holder William Trubridge. It was an AIDA International or CMAS in 2021 judged competition and has been the venue for multiple world and national records for athletes coming from countries all over the world.
Guillaume Néry is a French free diver.
Underwater sports is a group of competitive sports using one or a combination of the following underwater diving techniques - breath-hold, snorkelling or scuba, usually including the use of equipment such as diving masks and fins. These sports are conducted in the natural environment at sites such as open water and sheltered or confined water such as lakes and in artificial aquatic environments such as swimming pools. Underwater sports include the following - aquathlon, finswimming, freediving, spearfishing, sport diving, underwater football, underwater hockey, underwater ice hockey, underwater orienteering, underwater photography, underwater rugby, underwater target shooting and underwater video.
Skandalopetra diving dates from ancient Greece, when it was used by sponge fishermen, and has been re-discovered in recent years as a freediving discipline. It was in this discipline that the first world record in freediving was registered, when the Greek sponge fisherman Stathis Chantzis dived to a depth of 83 m in July 1913. It consists of a variable ballast dive using a skandalopetra tied to a rope. A companion on a boat recovers the diver by pulling the rope up after the descent, and keeps a watch on the diver from the surface.
Alexey Molchanov is a Russian champion freediver, multiple world champion, world record holder, and freediving promoter. He is also president of the "Freediving Federation" association, head of freediving school named in honor of Natalia Molchanova, and designer and engineer of the freediving equipment brand Molchanovs. Alexey is a son of Natalia Molchanova – multiple champion and world record holder in freediving.
Goran Čolak is a Croatian free-diver.
Kate Middleton is a New Zealand free-diver who holds the current New Zealand records in the free immersion (FIM) and constant weight with fins (CWT) disciplines. She is the third-deepest woman in the world and Vice World Champion Freediver. She owns a yoga and free-diving resort in Gili Trawangan, Indonesia, where she trains and teaches.
Nataliia Zharkova is a 2017 freediving champion of Europe and Ukraine. Zharkova holds multiple records in the discipline of freediving. She was also a freediving runner-up champion of the world in 2013. She is the first Ukrainian and the second woman to ever dive below the arch of the Blue Hole vertical underwater cave in Dahab, Egypt, on a single breath.
Alessia Zecchini is an Italian freediver who has set world and Italian records in freediving.
Estrella Navarro-Holm is a marine biologist, model, and national record-holding free diver from Mexico. She is the first Latin American woman to win a free diving medal for holding a single breath for more than six minutes.
Stephen Keenan was an Irish freediving safety diver and co-owner at Dahab Freedivers. He held several Irish national freediving records and was a Chief of Safety at various freediving events such as Vertical Blue Freediving Competitions.
