AIDA competitive freediving
AIDA is the Worldwide Federation for breath-hold diving. Established in 1992; AIDA manages and oversees the recognition of records, organises competitions, and sets the standards for freediving education. Since 1993, AIDA International has officiated 230 world records.
No Limit (NLT)
The freediver descends with the help of a ballast weight and ascends via a method of his choice. No limits is the deepest depth discipline. The athlete descends with a sled and ascends with a balloon, a diving suit ,or a vest with inflatable compartments, or whatever other means. NLT attempts are currently not sanctioned by AIDA International.
Variable Weight (VWT)
The freediver descends with the help of a ballast weight and ascends using his own power: arms and/or legs, either by pulling or not pulling on the rope. Variable weight is one of the two depth disciplines which employ the use of a sled to descend in the water. With old-style sleds, the athlete descended "head first" as seen in Luc Besson's famous movie "Le Grand Bleu", but new generation sleds are "feet first" which allows for easier equalization for the athlete. Variable weight is only done as a record attempt and is not a competition discipline.
Constant Weight (CWT)
The freediver descends and ascends with the use of fins/monofin and/or with the use of his arms. Pulling on the rope or changing his 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. Constant weight is the most widely practiced and known sportive depth discipline of freediving due to the specific fins or monofins used in it. Constant weight is one of the three disciplines included for international team competitions along with Static apnea and Dynamic with fins.
Constant Weight Without Fins (CNF)
The freediver descends and ascends underwater using a variation of breastroke swimming stroke without the use of propulsion equipment and without pulling on the rope. Constant weight without fins is the most difficult sportive depth discipline because it requires the most strength and the diver is unaided by fins . CNF exemplifies perfect coordination between propulsing movments, equalization, technique and buoyancy.
Free Immersion (FIM)
The freediver dives under water without the use of propulsion equipment (fins) but uses the rope to pull to descend and ascend. Free immersion is the most relaxing discipline and is used as a training tool to learn equalisaton techniques. Athletes may experience the most enjoyable sensations in FIM because of the speed of the water over the body and the power of each pull on the rope as the only means of propulsion.
Dynamic With Fins (DYN)
DYN is most often a pool discipline in which the freediver travels in a horizontal position underwater attempting to cover the greatest possible distance. Any propulsion aids, other than fins or a monofin and swimming movements with the arms, are prohibited. Dynamic with fins is the most common of the horizontal distance disciplines because of the specific means of propulsion ;long fins or monofin. For a performance to be officially recognized there are minimum depth and length requirements for pools. Pool competitions most often comprise a performance in DYN, DNF, and STA but some competitions are a combine’ of DYN and STA.
Dynamic Without Fins (DNF)
The freediver travels in a horizontal position underwater attempting to cover the greatest possible distance using a modified breaststoke . Propulsion aids of any sort are prohibited. DYN requires good technique, relaxation, and a long breath hold in order to achieve the greatest distance. The minimum pool standards are the same as for DYN.
Static Apnea (STA)
The freediver holds his breath for as long as possible with his nose and mouth immersed while floating on the surface of the water or standing on the bottom of a pool. Static apnea is the only discipline based on time of breathhold and not distance . It is one of the three disciplines included in Team World Championships along with CWT and DYN . Performances are recognized in both pool or open water (sea, lake, river, etc).
Find the current world records here.