Three of the most important elements in freediving (and spearfishing) is equalization, safety & breathing. Alchemy athlete, freediver, master instructor & content creator Carlos Negrete covers these three major areas in an understandable & meaningful way. Please note that these series of videos are not meant to replace a freediving course, there are actually made to encourage you attend one.
So what we want to look for this, what is happening with the frenzel technique is that we disengage our chest and our diaphragm, we close the gate here and we're gonna use the larynx as a pump to create and push air up, ok? What we need to do next is pinch our nose and seal our mouth in a comfortable way. After this, when we create the pressure and push it up, this is gonna send the air through those tubes, right in the middle ear and therefore we're gonna be able to equalize. We need to practice not only in the water, we need to practice dry, you can try with different positions, like with a handstand and then pressing with a nose clip or with different long volumes, like after a passive exhale, or even a full exhale and get familiar with this sensation. Another important tip, make sure you find the proper center or freediving instructor, because they're gonna help you to fix your problems easier and help you advance in a more efficient way.
Another tip, find the right center and the right instructor that can help you to overcome your issues giving you the right exercises and helping you to dive deeper. And last but not least, please never dive alone. Remember, this doesn't replace a freediving course, it's just some general concepts and information on what to expect from it.