“Pinch your nose and blow.” As scuba divers we’ve all heard that before. I’ve said it myself to many students in the past. But with that phrase comes tensed stomachs, bulging eyes and purple faces. </p><p>All divers know you have to equalize to go underwater and for some it comes easily, but how do you explain it properly to someone who has never done it before? </p><p>As I’ve gotten more and more into the sport of freediving, I’ve learned a lot more about equalizing, since it’s very important to be able to clear your ears reliably and quickly on the inverted descents and rapid ascents of breath-hold dives. But what I’ve learned from freediving has also taught me a lot about equalizing on scuba. </p><p><b>Two techniques</b></p><p>A little known scuba diving fact is that there are several types of equalization and each uses different technique. Two of the most common in scuba are the Valsalva and Frenzel techniques.</p><p>Most new divers who “pinch their noses and blow” use the Valsalva technique. In the Valsalva, divers bear down and clench their stomach and chest muscles to force air from their lungs up into their nasal passages, ear canals and sinuses, thereby equalizing their ears. </p><p>The problem with the Valsalva technique is that a diver must use a lot of effort to force the large volume of air from their lungs into their small, delicate ear canals, creating the familiar, tight-lipped, purple-faced diver that’s noisily trying to equalize their ears while making strange growly sounds as if they’re trying to lift a piano.</p><p>The excessive effort required to use this technique often makes it hard to equalize effectively, which can cause damage to a divers’ ears and is one of the most common causes of round window rupture, an ear injury that can very quickly end a diving career.</p><p>The preferred method of equalization is the Frenzel technique. In this technique divers take a small volume of air from their mouth and using their tongue like a piston to the upper back of their throat, piston air into their nasal passages and ear canals to equalize. By using a small amount of air and a modicum of effort and muscle movement, divers can equalize with ease, even at depth or during a freedive, when available air is limited to the volume in the diver’s lungs. In fact, it is nearly impossible to equalize past 15 feet while freediving if you’re using Valsalva.</p><p>But the real question is this: how do you know which one you’re using? A simple way to check is to put one hand on your stomach and equalize. Then put one hand on your throat and equalize. If you felt your stomach move, you’re most likely using Valsalva. If you felt only your throat move, you’re using Frenzel. </p><p>The good news is that if you just realized that you’ve been using Valsalva all this time, it is entirely possible to learn to switch to Frenzel. </p><p>The first step to mastering Frenzel is to practice each step of the technique. To practice get a cup of water and move somewhere that you can make a big mess, probably outside. Take a big mouthful of water, but don’t swallow. Try to spit out the water in a strong, steady stream. This messy practice mimics the motion your tongue makes when it acts as a piston, moving from the bottom of your mouth to the upper back of your throat. If you find you’re creating an explosion of water from your mouth, you’re still using Valsalva. </p><p>Once you’ve successfully done this several times, try to equalize using the same tongue technique. It should feel much easier than the Valsalva. </p><p>The final step to the technique is to consistently practice it every day, even if you’re not diving. The more you practice it, the more you create a habit that will take the strain off your ears and will make your overall diving experience more enjoyable, and if you’re into freediving like me, you might find that you can hit some depths that seemed unreachable before.