The Disciplines of Freediving

Freediving has eight official disciplines. Some measure depth. Some measure distance. One measures how long you can lie face-down in a pool without breathing. Each one is a different test of the human body — and a different way to experience what a single breath can do.

The flagship discipline. The one that makes the headlines.

You descend and ascend under your own power, with a monofin, along a vertical line. "Constant weight" means you can't drop weight during the dive — what you carry down, you carry back up. The monofin provides propulsion with a dolphin kick, turning your legs into a single powerful unit.

CWT produces the deepest dives of any discipline where the athlete returns under their own power. The technique is a balance of hydrodynamics, equalization, and mental calm. At depth, the monofin barely moves — the diver conserves every molecule of oxygen.

Below about 30 meters, you become negatively buoyant. The ocean literally pulls you down. Divers call this "free fall" — and it's the closest thing to flying in this world.

Same rules as CWT, but with two separate fins instead of a monofin. The kick technique is a standard flutter kick rather than a dolphin kick.

CWTB is newer as an official discipline, recognized by AIDA in 2019. Many divers consider it more natural than the monofin — it's closer to how humans actually swim. The trade-off: bi-fins are less efficient than a monofin, so depths are slightly lower.

Some divers train exclusively with bi-fins because the technique transfers better to recreational freediving. You don't need a monofin to enjoy the ocean.

The purest discipline.

No fins. No monofin. No propulsion assistance of any kind. You pull yourself down the line with your arms, and you swim back up using a modified breaststroke kick. It's you and the water. Nothing else.

CNF is considered the most physically demanding depth discipline because without fins, every meter costs more energy and more oxygen. The athletes who excel at CNF tend to have extraordinary efficiency — not power, but an almost inhuman ability to minimize movement.

William Trubridge trained at Dean's Blue Hole in the Bahamas — a vertical sinkhole over 200 meters deep. He often trains alone with only a safety team, because the blue hole is so remote that regular training partners are scarce. This is why he's such an advocate for building freediving communities.

You pull yourself down and back up using only the rope. No fins, no swimming. Just hand-over-hand along the dive line.

FIM is often the first deep discipline beginners try because the technique is intuitive — pulling a rope is something anyone can do. It also allows excellent body control during equalization, since your hands are on the rope rather than kicking.

Advanced FIM divers develop a fluid, almost meditative pulling rhythm. The descents look effortless. They aren't.

FIM is the preferred discipline for depth training because it lets divers focus entirely on equalization without worrying about fin technique. If your ears are the bottleneck (and for most divers, they are), FIM is where you work on it.

You descend with a heavy weight (a sled or weighted plate) and ascend under your own power — usually by pulling the rope or finning up.

Variable Weight allows deeper dives than CWT because the descent is passive — gravity does the work. But the ascent is harder, because you're deeper and you've already burned oxygen on the way down.

VWT is not competed at AIDA World Championships but is recognized as an official record category.

VWT is sometimes used as a training tool for No Limits attempts, because it simulates the deep descents without the complexity of a motorized sled.

The absolute frontier of human depth.

You descend on a weighted sled — a device that pulls you down on a rail along the dive line. You ascend using a lift bag (an inflatable balloon) or a mechanical device. No swimming required in either direction.

No Limits is the discipline that produces the deepest dives in human history. It's also the most dangerous, because the depths involved create extreme physiological stress: nitrogen narcosis, oxygen toxicity risk, blood shift beyond any other discipline, and decompression issues on ascent.

AIDA no longer officially sanctions NLT records due to safety concerns. The records listed are historical.

Herbert Nitsch's 214m record has stood since 2007. In 2012, he attempted 253m and suffered severe decompression sickness and multiple brain infarctions during the ascent. Doctors said he would never walk or speak again. He proved them wrong — and dives again today. The 214m mark remains unchallenged. It may stand forever.

The simplest and most brutal discipline.

Float face-down in a pool. Don't breathe. That's it.

No movement. No distraction. No depth to reach, no distance to cover. Just you, your lungs, and the ticking clock. Static Apnea is pure breath-hold, stripped of everything else. It's a battle between your body — which is screaming for air — and your mind, which knows you're fine.

The first contractions (diaphragm spasms demanding a breath) start around 2-3 minutes for most people. Competitive athletes push through 8, 9, 10+ minutes of contractions. The mental game is everything.

Natalia Molchanova's STA record has stood since 2013. She set it at age 51. No woman has beaten it in over a decade. To put 9:02 in perspective: the average untrained person blacks out around 1:30.

Swim as far as you can underwater in a pool. Horizontally. On one breath.

Three variants exist:

• DYN (Dynamic with fins) — monofin, dolphin kick
• DNF (Dynamic No Fins) — breaststroke only, no equipment
• DYNB (Dynamic Bi-Fins) — two fins, flutter kick

Dynamic is the pool equivalent of CWT. It's about efficiency: how far can you travel on a fixed amount of oxygen? Every unnecessary movement, every moment of tension, every imperfect kick costs distance.

The best DYN athletes swim with an almost robotic consistency. Their dolphin kick is identical from the first meter to the last. Turns at the wall are fluid. There's no wasted motion.

DYNB (bi-fins): Mateusz Malina — 290m+

300 meters underwater on one breath. That's 12 laps of a 25-meter pool. Without surfacing. Without breathing. The pool discipline records are as surreal as the depth records — just harder to visualize because we all know how long a pool is.