Why equalization gets harder with depth
As a freediver descends, ambient pressure increases and the gas spaces in the middle ear and airways are compressed. The pressure change is greatest near the surface, which is why frequent, gentle equalization early in the descent matters so much.
Frenzel equalization
Frenzel uses the tongue and throat structures to create pressure rather than relying on a strong exhalation from the chest. For freediving this is generally more efficient than trying to force a Valsalva-style push, especially as depth increases and lung volume falls.
What good Frenzel feels like
It should be controlled and repeatable, with minimal effort. If the neck, chest and face are straining, the diver is usually using more force than necessary or losing coordination between the tongue, glottis and soft palate.
The role of the soft palate and glottis
Equalization depends on directing pressure to the correct space. Learning to sense whether the soft palate is open or closed, and whether the glottis is controlling air movement, gives the diver much more precision.
Why equalization often fails around a certain depth
Common causes include waiting too long between equalizations, descending too fast for the diver’s current coordination, head position, insufficient relaxation, losing Frenzel mechanics as lung volume decreases, or trying to compensate with extra force.
Deeper equalization and mouthfill
At greater depth, advanced freedivers may use a mouthfill strategy: air is moved into the mouth before lung volume becomes too small to access comfortably, then that stored air is managed for subsequent equalizations. Mouthfill should be learned progressively with an experienced instructor because timing and airway coordination matter.
How to improve equalization
Dry practice can help develop awareness of tongue position, soft palate and glottis control, but the goal is quality rather than repetition for its own sake. In the water, descend slowly enough to equalize before pressure becomes uncomfortable and never treat pain as something to overcome.