Safety First

Freediving always requires a trained buddy. Never practice breath-hold diving alone - shallow water blackout can occur without warning and is survivable only if someone is present to respond.

— Chapter 01

How It Physically Works

Freediving is diving underwater on a single breath. No tanks. No regulators. No hoses. Just your lungs, the water, and however long you can stay down.

The human body has a built-in set of reflexes for breath-hold diving called the mammalian dive reflex. These are involuntary physiological responses to breath holding and water immersion — and they exist in all air-breathing mammals that swim.

When you submerge your face in water, your body immediately begins to adapt:

Heart rate slows (bradycardia)
conserving oxygen for vital organs
Blood shifts inward
away from limbs, toward the core and vital organs
Spleen contracts
releasing oxygen-rich red blood cells into circulation
Lungs compress
at depth, blood fills the thoracic cavity to prevent chest collapse

These responses mean the human body is far more adapted to diving than most people realize. With regular training, the dive reflex becomes stronger — heart rate drops faster, spleen response increases, and dive times improve.

— Chapter 02

The Disciplines

Freediving isn't one thing. There are several competitive and training disciplines, each testing a different aspect of breath-hold performance.

Pool Disciplines

  • Static Apnea (STA) — floating face-down, holding your breath as long as possible. No movement, no depth. World record: 24+ minutes.
  • Dynamic Apnea with Fins (DYN) — swimming horizontally underwater, fins only. Distance is the metric. World record: 300m.
  • Dynamic Apnea No Fins (DNF) — same as DYN but using only body movement. World record: 244m.

Open Water Disciplines

  • Constant Weight with Fins (CWT) — vertical depth diving under your own power, with fins. The most common discipline. World record: 131m.
  • Constant Weight No Fins (CNF) — depth diving with no fins — only dolphin kick. World record: 102m.
  • Free Immersion (FIM) — pulling yourself down and up a rope without fins. Excellent for learning equalization.
  • No Limits (NLT) — historically allowed any method (weighted sled, lift bag). No longer in active competition due to extreme risk.

Most recreational freedivers work in Constant Weight — descending and ascending vertically. That's what going freediving typically means.

— Chapter 03

Freediving vs Scuba Diving

These are two completely different experiences — not just in gear, but in how it feels underwater.

Freediving
Scuba
Breathing
Single breath
Continuous from tank
Gear weight
3–6 kg
15–25 kg
Bottom time
1–3 min per dive
30–60 min per tank
Sound underwater
Silent
Constant bubbles
Marine life reaction
Calm, natural
Often wary
Gear cost (beginner)
$300–500
$1,500–3,000+

Marine animals — dolphins, whales, reef fish — react differently to a silent, bubble-free diver. Many freedivers describe it as more intimate with the ocean. The two sports are not mutually exclusive. Many divers do both.

— Chapter 04

Spearfishing

Many freedivers come to the sport through spearfishing — and the skills transfer directly. Breath hold, descent technique, equalization, and open water comfort are identical foundations.

Spearfishing has its own rules around local regulations, species restrictions, and marine protected areas. But the skill base is the same.

— Chapter 05

Is Freediving Right for You?

Freediving suits people who are:

  • Comfortable in open water (not just pools)
  • Physically fit enough for sustained swimming
  • Patient enough to develop the mental side of breath holding

The fastest path to progression: a beginner course, regular pool training with a buddy, and time in the water.