Constant Weight without fins

Constant weight without fins is an AIDA International (International Association for Development of Apnea) free-diving discipline in which the free-diver descends and ascends by swimming without the use of fins or without pulling on the rope or changing his 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.

The three main differences between free diving disciplines that involve diving to depth and those that occur at the surface are that you can not interrupt the dive, there are periods where work is performed and the diver is impacted by direct effects of pressure.

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