Freediving Equalization Techniques - Frenzel, Valsalva, and Beyond

Equalization is the skill that gates depth progress more than anything else in freediving. A diver who can't equalize reliably cannot go deep — it's a hard physiological limit, not a matter of fitness or breath-hold capacity.

As you descend, water pressure increases. Every air-filled space in your body — ear canals, sinuses, mask — must equalize against that pressure. Your ears equalize through the Eustachian tubes, which connect the middle ear to the back of the throat. Opening the Eustachian tubes allows air to flow from the throat into the middle ear, balancing the pressure.

If you don't equalize:

• The eardrum is pushed inward by pressure differential
• This causes pain, then squeeze, then potential rupture
• A ruptured eardrum requires weeks of recovery and risks permanent hearing loss

How it works

pinch your nose and blow gently against the closed nostrils — increases pressure in the throat and forces air through the Eustachian tubes into the middle ear

When it works

at shallow depths — intuitive, easy to learn, and effective down to about 10–15m

Why it fails at depth

Valsalva relies on lung pressure. As you descend, your lungs compress significantly under water pressure. By 20–30m, generating enough Valsalva pressure becomes difficult or impossible — the technique stops working exactly where you need it most.

Frenzel does not use lung pressure. It uses a specific motion of the tongue and throat to push air into the Eustachian tubes — independent of chest compression. Frenzel works at any depth because the muscles used — tongue and throat — are not affected by chest compression.

The movement

1. 01 —Pinch the nose
2. 02 —Close your glottis (throat) — make the throat 'click' closed as if holding your breath while swallowing
3. 03 —With the glottis closed, move the back of your tongue up and forward
4. 04 —You should feel (or hear) air moving to equalize

This tongue piston action generates pressure in the throat that opens the Eustachian tubes — without requiring the lungs to generate pressure.

The challenge: Frenzel requires isolating muscles most people have never consciously controlled. This takes practice.

Dry practice method

1. 01 —Pinch your nose closed
2. 02 —Close your glottis — the 'click' feeling when you swallow and hold the position
3. 03 —With glottis closed, move the back of your tongue up and forward (like saying 'K' or 'G')
4. 04 —You should feel equalization happen without any chest involvement

If it's not working

• Practice in front of a mirror — watch for chest movement (chest movement = you're still using Valsalva)
• Try the Frenzel 'K' sound — the tongue position for the letter 'K' is close to the Frenzel position
• Practice 10–15 minutes per day, dry, with a nose clip

At extreme depths (roughly 30m+ depending on the diver), even Frenzel has limits — the throat air supply becomes insufficient as the chest compresses dramatically.

Mouthfill solves this by storing a mouthful of air at a shallower depth, closing the glottis to trap it, and using that supply to continue equalizing during the deeper portion of the descent. This is an advanced technique — not needed for recreational diving, but worth knowing it exists.

Summary Rules

1. 01 —Equalize early — every 1–2m, before pressure
2. 02 —Learn Frenzel — Valsalva has an inherent depth ceiling
3. 03 —Practice Frenzel dry until it's consistent before relying on it underwater
4. 04 —Never force through ear pain — ascend and try again, or end the dive
5. 05 —Don't dive congested — blocked tubes can't equalize regardless of technique