How to Equalise for Freediving

Equalisation is the single biggest technical challenge for new freedivers. It's the reason most beginners hit a depth ceiling, the source of most ear pain underwater, and the skill that separates comfortable diving from forced, anxious descents.

The good news: equalisation is a learnable skill. It's not about genetics or ear anatomy — it's about technique. Once you understand what's happening in your ears and learn the right method, depths that felt impossible become routine.

This guide covers everything you need to know about equalising for freediving — why it's necessary, how each technique works, how to practise on dry land, and how to troubleshoot the most common problems. If you're new to freediving, start with our complete guide to freediving in Melbourne for broader context.

Why You Need to Equalise

Your middle ear is an air-filled space sealed behind the eardrum. As you descend underwater, water pressure increases — roughly one atmosphere for every 10 metres of depth. That increasing pressure compresses the air space in your middle ear, pushing your eardrum inward.

This is Boyle's Law in action: as pressure increases, the volume of a gas decreases. At 10 metres, the air in your middle ear is compressed to half its surface volume. At 20 metres, one-third. Your eardrum is a thin, flexible membrane caught between the pressurised water outside and the shrinking air space inside.

Without equalisation, this pressure imbalance causes pain — first as a feeling of fullness, then sharp discomfort, and eventually injury. A ruptured eardrum (barotrauma) is one of the most common injuries in diving, and it's almost always caused by descending without equalising or by forcing an equalisation that isn't working.

Equalisation solves this by sending air from your throat up through the Eustachian tubes — two narrow passages that connect your throat to your middle ears. When air reaches the middle ear, it restores the pressure balance, the eardrum returns to its neutral position, and the discomfort disappears instantly.

The challenge is that Eustachian tubes don't open on their own during descent. You need to actively push air through them. How you do this — and how efficiently — determines how deep you can dive comfortably. For more on the risks involved, see our guide on whether freediving is dangerous.

The Valsalva Technique

The Valsalva manoeuvre is what most people learn first. It's the technique you instinctively use on an aeroplane: pinch your nose and blow gently against your closed nostrils. The air pressure in your throat rises, forcing air up through the Eustachian tubes and into the middle ear.

How to Perform the Valsalva

1. Pinch your nose closed with your fingers (or press your mask against your nose)
2. Close your mouth
3. Gently try to exhale through your nose — you should feel pressure build in your ears
4. When you feel a soft pop or click in one or both ears, the equalisation is complete

Why Valsalva Has Limitations for Freediving

The Valsalva works fine for scuba diving, where you have unlimited air supply and typically descend slowly. For freediving, it has significant drawbacks:

• It requires chest and diaphragm effort — You're using your respiratory muscles to generate pressure, which consumes oxygen and creates tension in your body
• It fails at depth — As you descend, increasing water pressure compresses your lungs. Below about 20-30 metres, there simply isn't enough air volume in the lungs to generate the pressure needed for a Valsalva. The technique stops working entirely
• It's all-or-nothing — Valsalva tends to deliver a sudden blast of pressure rather than a controlled, gentle push. This makes it easy to over-pressurise and potentially damage the eardrum or round window
• It doesn't work well head-down — In a head-first descent, the Valsalva becomes less effective because air naturally rises away from the Eustachian tubes

For recreational snorkeling and shallow dives to 5-10 metres, Valsalva is adequate. But if you want to progress in freediving, you need to learn Frenzel.

The Frenzel Technique

The Frenzel technique is the standard equalisation method for freediving. It was developed by Hermann Frenzel, a Luftwaffe commander who taught it to pilots dealing with rapid altitude changes during World War II. Today, it's taught in every credible freediving course worldwide.

Instead of using your chest and diaphragm to push air (like Valsalva), Frenzel uses your tongue as a piston. You trap a small amount of air in your mouth and throat, seal it off from the lungs by closing the glottis (the back of the throat), and then use your tongue to compress that air upward through the Eustachian tubes.

Why Frenzel Is Superior for Freediving

• No chest effort required — Only the tongue moves, keeping your body relaxed and conserving oxygen
• Works at greater depths — Because it uses air already in the mouth and throat, it's not limited by lung compression. Frenzel works reliably to around 30-40 metres (beyond that, the mouthfill technique takes over)
• Gentle and controllable — The tongue delivers precise, controlled pressure rather than a forceful blast
• Works in any body position — Equally effective head-up, horizontal, or head-down
• Can be performed continuously — You can equalise every second during descent without interrupting your streamline or relaxation

Step-by-Step: Learning the Frenzel

The Frenzel is not intuitive at first. It involves a movement your body has never been asked to make deliberately. Be patient — most people need several days to several weeks of daily practice before it becomes automatic.

1. Understand the glottis lock — The glottis is the opening at the back of your throat, controlled by your vocal cords. To close it, make the sound "kuh" or "guh" and freeze at the moment your throat closes. You should feel a seal at the base of your throat. Try breathing in — if no air gets through, the lock is working
2. Fill your mouth with air — Take a breath and trap a mouthful of air. Close your glottis to seal that air off from your lungs. Your cheeks should be slightly puffed
3. Pinch your nose — Close both nostrils with your fingers
4. Use the tongue as a piston — With the glottis locked and nose pinched, push the back of your tongue upward toward the roof of your mouth, like pronouncing the letter "T" or "K". This compresses the air trapped in your mouth and throat, forcing it through the Eustachian tubes
5. Feel for the pop — If successful, you'll feel a gentle pop or pressure shift in one or both ears. This means air has entered the middle ear

Practice Drill: The "T-K" Exercise

This is the single most useful dry-land exercise for learning Frenzel:

1. Pinch your nose
2. Fill your cheeks with air and lock the glottis
3. Rapidly alternate between the sounds "T" and "K" (without vocalising — just the tongue movements)
4. Each "T" and "K" should produce a small click or pressure change in your ears
5. Practice for 2-3 minutes, several times per day

Once you can reliably produce ear clicks with this exercise while sitting at your desk, you're ready to try it in the water.

Mouthfill Technique (Advanced)

The mouthfill is an extension of Frenzel used by advanced and competitive freedivers for depths beyond 30-40 metres. At these depths, even the air trapped in your mouth and throat during Frenzel becomes significantly compressed. The mouthfill addresses this by loading the mouth with as much air as possible at a specific depth (usually around 20-30 metres), then using tiny tongue movements to meter out that air for many subsequent equalisations during the remainder of the descent.

Mouthfill is not something beginners need to worry about. It requires a solid Frenzel foundation and is typically taught in advanced freediving courses (Level 3 and above). However, understanding that it exists helps explain why world-class freedivers can reach depths of 100+ metres without equalisation failure.

Common Equalisation Problems and Solutions

Can't Equalise One Ear

This is the single most common equalisation complaint. One ear clears easily while the other stubbornly refuses. The cause is almost always anatomical — one Eustachian tube is slightly narrower, more angled, or has more tissue around it than the other.

• Tilt your head — Turn the problem ear toward the surface. This can change the angle of the Eustachian tube and help it open
• Jaw movements — Wiggling your jaw side to side or jutting it forward can help open a reluctant tube
• Swallow while equalising — Combining a swallowing motion with Frenzel activates additional muscles around the Eustachian tube
• Ascend and retry — Never force it. Rise a metre or two, equalise successfully, then continue down. Forcing a stuck equalisation is the fastest path to injury

Pain at a Certain Depth

If you consistently hit a depth where equalisation becomes painful or impossible, the most likely causes are:

• You're not equalising early enough — Start equalising at the surface, before you feel any pressure. Then equalise every metre during the first 10 metres, where pressure changes most rapidly
• You're descending too fast — Slow your descent in the first 10 metres. The pressure change per metre is greatest near the surface (the first 10 metres doubles the pressure on your ears; the next 10 metres only increases it by a third)
• Technique is breaking down under pressure — Stress and exertion cause tension in the throat and face, making equalisation harder. Focus on relaxation
• You're reaching the limit of your current technique — If you're using Valsalva, this is a sign it's time to learn Frenzel

Congestion Issues

Mucus and swelling in the nasal passages or around the Eustachian tubes make equalisation difficult or impossible. Common culprits include:

• Head colds and flu — Do not dive when congested. The swelling prevents equalisation and can lead to a reverse block on ascent, where air gets trapped in the middle ear and cannot escape
• Hayfever and allergies — Seasonal allergies are common in Melbourne. If your nose is blocked, equalisation will suffer. Antihistamines can help, but discuss with your doctor before diving on medication
• Dairy and diet — Some freedivers find that dairy products increase mucus production. Consider avoiding dairy for a few hours before diving
• Nasal rinse — A saline nasal rinse (neti pot or squeeze bottle) 30-60 minutes before diving can clear the passages and improve equalisation significantly

Dry Land Practice Exercises

You do not need to be in water to practise equalisation. In fact, most of the skill development happens on dry land. Consistent daily practice — even just 5 minutes — will accelerate your progress far more than occasional pool sessions.

Exercise 1: Glottis Lock Isolation

Say "kuh" and freeze at the moment your throat closes. Hold the lock for 5 seconds. Release. Repeat 10 times. The goal is to be able to engage and disengage the glottis lock at will, without any other movement in your face, jaw, or chest.

Exercise 2: Cheek Inflation Without Lungs

Lock the glottis. Using only your tongue, push air into your cheeks so they inflate. Then pull the air back with your tongue so your cheeks deflate. Repeat — inflate, deflate, inflate, deflate — without ever opening the glottis. This trains the tongue piston movement that powers the Frenzel.

Exercise 3: Frenzel with Nose Pinched

Pinch your nose, fill your cheeks with air, lock the glottis, and perform the Frenzel tongue movement. You should feel pressure shift in your ears with each repetition. Practice in sets of 10, multiple times per day. Over time, the movement should feel effortless and automatic.

Exercise 4: Frenzel While Inverted

Once you can Frenzel comfortably sitting upright, practise while lying on your back, then while hanging your head off the edge of a bed (simulating a head-down position). Equalisation is harder when inverted because air naturally wants to rise away from the Eustachian tubes. Practising inverted builds the skill you'll need during real dives.

These exercises pair well with the breathing techniques covered in our breath-hold training guide for beginners. Combining equalisation and breath-hold practice accelerates your readiness for pool and open water sessions.

Tips for Equalising in the Water

Equalise Early and Often

The single most important rule: start equalising before you feel pressure. Your first equalisation should happen at the surface, before your head is even submerged. Then equalise every metre for the first 10 metres — not every 2-3 metres, every single metre.

Why? The pressure change is greatest near the surface. Going from 0 to 1 metre adds roughly 10% more pressure to your ears. Going from 30 to 31 metres adds less than 3%. Most equalisation failures happen in the first 10 metres because divers don't equalise frequently enough during the zone of greatest pressure change.

Head Position Matters

In a head-first descent (which is standard for freediving), keeping your chin slightly tucked toward your chest can help the Eustachian tubes open more easily. Looking upward (extending the neck) tends to stretch and narrow the tubes, making equalisation harder. Find the head position that works best for your anatomy.

Control Your Descent Speed

Slow down in the first 10 metres. This gives you time to equalise at each metre mark. Many beginners try to descend quickly, outpacing their ability to equalise. A controlled, slower start that speeds up after 10-15 metres is far more effective than a fast start that ends with an equalisation failure at 8 metres.

Stay Relaxed

Tension in your neck, jaw, and face makes equalisation harder. If you're anxious, your muscles tighten and the Eustachian tubes are more difficult to open. Focus on relaxing your face and jaw throughout the descent. A relaxed diver equalises more easily than a tense one at every depth. Our guide on pool training in Melbourne covers how to build this relaxation in a controlled environment.

Pre-Equalise at the Surface

Before your dive, perform several gentle Frenzel equalisations at the surface. This pre-opens the Eustachian tubes, stretches the tissues, and makes the first few metres of descent significantly easier. Think of it as warming up your ears the way you'd warm up muscles before exercise.

When NOT to Dive

There are situations where no technique will help, and attempting to dive will cause injury. Do not freedive if:

• You have a head cold or flu — Swollen Eustachian tubes cannot be forced open. Risk of barotrauma and reverse blocks
• You have an ear infection — Diving with an ear infection can cause severe pain, spread the infection, and potentially rupture the eardrum
• You are heavily congested from allergies — If a saline rinse doesn't clear the congestion, don't dive. Wait until your passages are clear
• You experienced a recent equalisation injury — If you had ear pain, bleeding, or hearing changes on a previous dive, see a doctor before diving again. Do not "test it" by going back in the water
• You just had dental or sinus surgery — Follow your surgeon's advice about when to resume diving. Air spaces in the sinuses and jaw are also affected by pressure changes

Skipping a dive is always better than forcing one and spending weeks recovering from an ear injury. The ocean isn't going anywhere.

How Melbourne Freediving Courses Teach Equalisation

Every reputable freediving course in Melbourne devotes significant time to equalisation instruction. Here's what to expect:

• Theory session — Detailed anatomy of the ear, physics of pressure, and the mechanics of each equalisation technique. Understanding the "why" makes the "how" click faster
• Dry land practice — Guided exercises in the classroom. Instructors check each student individually and diagnose issues in real time
• Pool sessions — Practising equalisation during controlled descents in a pool, typically 3-5 metres deep. This is where the technique becomes real — doing it underwater, head-down, while managing a breath hold
• Open water application — Finally, applying the technique during ocean dives, usually at Mornington Peninsula pier sites or other sheltered Melbourne locations
• One-on-one troubleshooting — Good instructors spend individual time with students who are struggling. Equalisation is the most common bottleneck in beginner courses, and experienced teachers have seen every variation of the problem

If you're considering taking a course, our guide to choosing a freediving course in Melbourne covers what to look for in an instructor and school, including how much time they dedicate to equalisation training.

Frequently Asked Questions

What is the best equalisation technique for freediving?

The Frenzel technique is the standard equalisation method for freediving. Unlike the Valsalva manoeuvre, Frenzel uses the tongue as a piston to compress air into the Eustachian tubes, requiring minimal effort and working reliably to depths of 30-40 metres. Most freediving courses in Melbourne teach Frenzel as the primary technique from day one.

Why can I equalise one ear but not the other?

Asymmetric equalisation is very common. One Eustachian tube is often slightly narrower or more angled than the other. Try tilting your head so the problem ear faces the surface, which can change the angle and help the tube open. Gentle jaw movements or swallowing while attempting to equalise may also help. Never force it — if one ear will not clear, ascend slightly and try again.

How long does it take to learn the Frenzel technique?

Most people develop a basic Frenzel within 1-3 weeks of daily dry-land practice. Some pick it up in a single afternoon; others need a month or more. The key variables are how much time you dedicate to practice, whether you have in-person instruction, and your individual anatomy. A freediving course dramatically shortens the learning curve for most people.

Can I freedive if I have trouble equalising?

Yes, in most cases. Equalisation difficulty is extremely common among beginners and usually improves dramatically with practice and proper technique. Most people who struggle are simply using the wrong method (Valsalva instead of Frenzel) or are not equalising early or often enough. A qualified instructor can diagnose your specific issue and help you overcome it. Very few people have anatomical conditions that truly prevent equalisation.