Freediving disciplines: what each one tests

The core disciplines

Freediving is not one single sport. It splits into several distinct categories based on what the diver tests. Some focus on time, while others focus on distance or depth.

Most recreational divers aim for surface diving in tropical waters. They want to see reefs without heavy tanks. Professional athletes train for specific competitive metrics. You must choose your path carefully.

In 2021, I watched a local training session in Koh Tao. The divers were split between pool work and ocean drills. It showed how different skills require different environments.

Static apnea (STA)

Static apnea is the simplest form of breath-holding. You lie still in a pool or on land. The goal is to stay underwater for as long as possible. It is purely a mental game.

World records now exceed 11 minutes for men. This requires incredible CO2 tolerance and relaxation. It is not about movement. You just exist.

Many beginners start here. It feels safe because you stay in one spot. However, the urge to breathe can be violent after several minutes. You must learn to manage contractions.

Training for STA helps your lung capacity. It does not help your technique in the ocean. Do not expect a 5-minute pool hold to make you a deep diver. They are different skills.

Dynamic apnea (DYN)

Dynamic apnea tests how far you can swim horizontally. You use fins to move through a swimming pool. This discipline measures efficiency and oxygen economy.

There are two main types of dynamic training. One uses large monofins, while the other uses bifins. Most people practice DYN to improve their streamlined movement. It builds cardiovascular endurance.

I remember my first DYN session in 2015. My legs burned after only 40 m. The struggle is real. You must maintain a perfect glide to save energy.

Competitive DYN distances reach over 300 m per breath. This requires precise technique. If your form breaks, you waste oxygen immediately. Efficiency is everything here.

Constant weight freediving (CWT)

Constant weight is the most popular depth discipline. You descend and ascend using fins. The rule is that you cannot drop any weight during the dive. Your total weight stays the same.

This is what most people mean by deep freediving. You dive to a target depth, say 30 m, and come back up. It relies on buoyancy control and equalization. Depth changes everything.

Pressure becomes a major factor below 10 m. You must master the Frenzel or Mouthfill technique. Without these, you will hit a wall quickly. Most beginners fail here.

Constant weight freediving requires significant ocean experience. You cannot practice this safely in a shallow pool. The environment is much more unpredictable. Currents and temperature matter.

No fins freediving (CNF)

Constant Weight No Fins (CNF) is the purest discipline. You use only your arms and legs to move. There are no tools to help you glide. It is incredibly taxing on the body.

Many pros consider CNF the ultimate test. It requires massive core strength. You also need perfect coordination. It is very slow compared to CWT.

I saw a diver in Anilao attempt a CNF descent. He looked like he was fighting the water. Every movement had to be calculated. One wrong stroke ruins the dive.

Because you lack fins, your surface area is higher. This makes you less efficient. You must stay extremely calm to succeed. It is a beautiful but brutal discipline.

The gap between pool and ocean

Many novices make a huge mistake. They think high pool numbers translate to deep ocean dives. This is rarely true. The two environments are fundamentally different.

In a pool, you have perfect visibility and no pressure changes. You do not need to equalize your ears. The water temperature stays constant. It is a controlled vacuum.

Ocean diving involves many new variables. You face currents, surge, and varying salinity. Your ears must handle pressure at 20 m or 30 m. This is where the real work begins.

If you spend 6 months doing only STA, you will be unprepared for the ocean. You might have great breath-hold. However, you will likely struggle with equalization. Always train for both.

Safety is the biggest difference. In a pool, a blackout happens in a controlled setting. In the ocean, it can happen near a reef or in a current. You must respect the depth. Follow guidelines from DAN regarding blackout risks.

Equipment and discipline selection

Your gear choice depends on your discipline. A monofin is great for DYN or CWT. It provides massive thrust. However, it is terrible for CNF. You cannot use it there.

Long carbon fins are standard for CWT. They offer the best energy return. For recreational diving, simple bifins often suffice. Choose gear that matches your goals. Do not overspend early.

I suggest starting with basic equipment. Buy a good mask and a snorkel first. Once you know if you love CWT, invest in carbon fins. This saves money in the long run.

Some divers use weighted belts for training. In CWT, you must be careful with weight. You want to be neutrally buoyant at a specific depth. Too much weight makes the ascent impossible. Too little makes the descent too fast.

Summary of testing metrics

To summarize, each discipline tests a different physiological system. STA tests your mental grit and CO2 tolerance. DYN tests your horizontal efficiency and aerobic capacity. CWT tests your vertical technique and pressure management. CNF tests your total body strength and coordination.

Most people find they prefer one over the others. You might love the stillness of STA. Or you might crave the power of CWT. There is no wrong choice. Just find what fits you.

If you want to dive deep, start with a foundational course in a calm area. Do not attempt depth without a trained buddy. Safety is non-negotiable in this sport.

If you are currently training in a pool, start practicing your equalization techniques early. If you have never dived in a current, practice your buoyancy at Crystal Bay before heading to the heavy surge of Manta Point.

Frequently asked questions

Does pool training help with deep dives?

Pool training builds CO2 tolerance and mental focus. However, it does not teach equalization at depth or pressure management below 10 m.

What is the hardest freediving discipline?

Many athletes find Constant Weight No Fins (CNF) the most difficult because it requires extreme physical efficiency and strength.