Deep diving – Constant Weight (CWT)
refers to the most competitive and sought-after titles, using a monofin and the body’s own power to propel the diver down and up again.
Deep diving – Constant Weight No Fins (CNF)
seen by many as the purest form of competitive freediving, the diver uses only arms and legs to perform the dive, swimming breaststroke down and back up.
Deep diving – Free Immersion (FIM)
a test of upper body strength and endurance, the diver pulls down a weighted line, and back to the surface again.
Note – all deep competitive dives are ‘constant weight’, as it means we can use weight to assist the descent but must return with the same amount of weight – so a balancing act between an easy descent and an efficient ascent has to be found. Most divers use between 1-5 kilos depending on their size, thickness of suit and water they are diving in.