The fix is almost always the same: replace the chest-pressure equalization technique (Valsalva) that most beginners default to, with the tongue-and-soft-palate technique called Frenzel. Frenzel is harder to learn, but once it clicks, equalization stops being the bottleneck for almost everyone.
The good news is that Frenzel is trainable on dry land. You don't need a pool, you don't need water, you don't need anyone else. Twenty minutes a day for two weeks gets most students from "I can't do this" to "this is automatic." This guide walks through the drills that work.
Pairs with our broader guide to equalization and our 4-week AIDA 2 prep plan. If you've already read those, this is the practical follow-up: where the rubber meets the road.
Why Valsalva fails at depth — the short version
The technique most non-divers default to — pinch the nose, blow against the closed nose with chest pressure — works fine in shallow water. It fails for two reasons as depth increases.
First, it requires positive lung pressure. At 20 meters, your lungs are compressed to one-third of their surface volume. The pressure needed to overcome the surrounding water increases. Your chest can't generate that pressure forever, and somewhere between 10 and 25 meters, depending on the diver, Valsalva simply stops working.
Second, the chest engagement that Valsalva requires triggers a stress response. The body interprets "tense the chest and push" as effort, which raises heart rate, increases oxygen consumption, and tightens the diaphragm. Even when Valsalva technically works at depth, it costs the diver dive time and relaxation.
Frenzel solves both problems. The mechanic uses only the tongue and soft palate, leaving the chest completely relaxed. The pressure source is a small pocket of air in the mouth and throat, compressed by the tongue. This works at any depth, costs no chest engagement, and is what every elite freediver above 20 meters uses.
The Frenzel mechanic, broken down
Frenzel has three components that have to work together:
1. Soft palate closure
The soft palate is the soft tissue at the back of the roof of your mouth. When it's relaxed, air can flow between your mouth and your nasopharynx (the space behind your nose). When it's engaged, it seals off the nasopharynx from the mouth.
For Frenzel, the soft palate has to be in a specific position — closed off from below (so chest pressure can't reach your mouth) but open above (so air can move from your mouth into the nasopharynx and out through the nose).
You can feel the soft palate in two positions:
- Make the sound "kuh" (like the start of "key"). The back of your tongue rises and presses against the soft palate. This is the closure.
- Pretend to swallow but stop halfway. You'll feel the soft palate engage in a different way.
Practice finding the soft palate. Most beginners have never consciously moved this tissue and need a week of attention before they can engage it on demand.
2. Tongue position — the T position
The tongue does the work of compressing the air. The specific position is:
- Tongue tip pressed firmly against the ridge of tissue just behind your upper front teeth (where the roof of your mouth starts to curve)
- Sides of the tongue along the upper molars
- Body of the tongue ready to push forward and up
This is the same position you make when you produce the sound "tuh" (like the start of "tea"). The T position seals the mouth at the front, isolating a pocket of air between the tongue and the soft palate.
3. The tongue pump
From the T position, with the soft palate engaged, the tongue moves forward and up. The motion is small — maybe a quarter inch — but it compresses the air pocket in your mouth and forces it into the nasopharynx. The compressed air can only go one direction: up through the nasopharynx and out the nostrils into the eustachian tubes, which equalize your ears.
The whole motion is fast — less than half a second per pump. A trained freediver can pump the tongue multiple times per second during a continuous descent, equalizing the ears continuously without interrupting the dive.
The basic dry drill — the K-T sequence
This is the foundation. Practice it twenty times a day, every day, for a week.
- Pinch your nose closed
- Close your mouth, lips together
- Make the "kuh" sound silently, without exhaling. You should feel the soft palate close.
- Hold that position
- Without releasing the K, transition to the "tuh" sound — tongue tip to the ridge behind your front teeth
- Push the tongue forward and up
- You should feel air pop into your ears
If you don't feel anything in your ears, something is leaking. The two most common errors:
- The soft palate isn't fully closed. Practice the K-sound in isolation until you can hold the closure with your nose pinched and feel that no air is escaping anywhere.
- The tongue isn't sealed at the back. Air is escaping past the back of the tongue and down your throat. Press the back of the tongue more firmly against the soft palate.
Twenty reps a day. By the end of week one, the motion should be automatic — you should be able to pump your ears without thinking about it.
The diagnostic — can you feel each part working?
A clean Frenzel has a specific feel. To diagnose your technique, try these isolation tests:
Cheek puff test
Pinch your nose, do a Frenzel pump, and watch your cheeks. They should not puff out. If they do, you're using cheek pressure rather than tongue pressure. The mouth cavity should be the source of compression, not the cheeks.
Chest stillness test
Put one hand on your chest. Do a Frenzel pump. Your chest should not move at all. If it does, you're sneaking in chest pressure to help. Practice with the hand on chest as a check; eventually you'll feel the difference and won't need the external reminder.
Glottis closure test
Take a half-inhale and hold it. Mock a held cough — the click in your throat is your glottis closing. With the glottis closed, your lungs are sealed off from your mouth. Now try a Frenzel pump. The motion should still work — because Frenzel doesn't depend on lung pressure.
If Frenzel only works when your glottis is open and lung pressure can reach your mouth, you're still doing a hybrid Valsalva-Frenzel. Train the glottis-closed version until it works in isolation.
The bubbler trainer — visual feedback that doesn't lie
For students who pass the dry diagnostics but still can't equalize in the water, the next step is a bubbler trainer. The summary:
A mason jar partially filled with water, with a tube going through the lid down into the water. Outside the jar, the tube ends in a soft nasal tip. The student inserts the tip in one nostril, pinches the other nostril shut, closes the mouth, and pumps Frenzel air through. Bubbles emerge at the submerged tube tip — but only if real pressure is being generated. Lung air escaping past a loose soft palate doesn't sustain the bubble pattern. The water column gives objective feedback that you can't fake.
If you can produce clean discrete bubbles at the bubbler, your Frenzel works. If you can't, something is leaking, and the bubbler reveals which mechanism is failing.
The bubbler is the diagnostic gold standard for dry Frenzel training. It catches issues that pass the cheek puff and chest stillness tests but still fail in the water.
Week-by-week progression for the AIDA 2 student
Week 1 — Mechanic discovery
Focus: finding the soft palate and the T tongue position. 20 reps per day of the K-T sequence. End of week, you should be able to feel both components engaging consistently.
Week 2 — Repetition and speed
Focus: making the motion automatic. 50 reps per day, spread across multiple short sessions (5–10 minutes at a time). Variation: train both nostrils equally — sometimes pinch the left, sometimes the right. Aim for a sequence of 10 clean pumps in a row without conscious thought about the mechanic.
Week 3 — Bubbler or wand verification
If you have access to a Frenzel bubbler or nasal balloon trainer, use it daily. Otherwise, do the dry pumps with one hand on your chest as the external check. By the end of week 3, you should be able to produce 10 successful pumps in a row with no chest movement.
Week 4 — Head-down integration
The final step before water. Practice Frenzel pumps lying flat on your back, then lying with your head hanging off the edge of a bed (inverted). The position changes the geometry slightly — the airway is in a different orientation, and the soft palate has to engage against gravity rather than with it.
Most beginners find inverted Frenzel harder than upright Frenzel. This is the exact challenge you'll face in the water: equalizing during a head-down descent. Train the inverted version on dry land before you face it at depth.
Common patterns of failure
"I can do it lying down but not standing up." The soft palate engagement is gravity-dependent for many beginners. The fix is more reps in all positions until the closure is robust to orientation.
"It works on the left nostril but not the right." One eustachian tube is more reactive than the other for most people. Train the weaker side specifically. This isn't a Frenzel technique problem — it's eustachian tube function variability.
"I can feel the pump but my ears don't pop." The mechanic is right but you're not generating enough pressure to overcome the eustachian tube resistance. Press the tongue harder. Use shorter, sharper pumps rather than slow gradual ones.
"It worked yesterday and doesn't work today." Allergies, sinus congestion, or fatigue can all reduce eustachian tube function temporarily. Pre-treat with your usual nasal spray or antihistamine if seasonal allergies are a factor. Don't try to force equalization through congestion — wait for a cleaner day.
"I'm doing all the drills but it still feels wrong." Get a video tutorial in front of you. The Adam Stern Frenzel videos on YouTube are the cleanest visual reference for the technique. Sometimes the missing piece is seeing the motion modeled from the outside.
What to expect when you get in the water
Dry Frenzel training gets you 70–80% of the way to in-water equalization. The remaining 20–30% comes from the specific demands of descent — the pressure increasing in real time, the cold of the water, the orientation changes, and the small interferences (mask squeeze, distraction, fatigue) that compound during a real dive.
Most students who've trained Frenzel dry for two weeks find that their first depth attempt in a course is dramatically smoother than it would have been otherwise. They don't have to invent the technique under pressure — they're refining a skill they already have.
The students who skip dry training and try to learn Frenzel for the first time in 4 meters of water on day two of an AIDA 2 course tend to struggle. The mechanic isn't intuitive, and the cognitive load of learning it while also managing all the other demands of a real dive is too high. Dry training removes that bottleneck.
Sources and further reading
- LJFC: The Complete Guide to Equalization for Freediving — broader treatment of equalization techniques and theory.
- LJFC: 4-Week AIDA 2 Prep Plan — the broader prep context this drills fits into.
- For LJFC students: ask Joshua about the in-house Frenzel bubbler trainer used during course pool sessions.
- Adam Stern. Frenzel Equalization for Freediving (YouTube tutorial series). The clearest visual reference for the dry mechanic.
- Eric Fattah. Frenzel-Fattah Equalization Technique documentation. The historical reference for the technique.
- Pelizzari, U. Manual of Freediving: Underwater on a Single Breath. Idelson Gnocchi, 2004. Chapter on equalization.
- AIDA 2 standards — the 12-meter Constant Weight requirement that this drill prepares you for.
