Mouthfill - How many times?

[Bandos]

Hi everyone,

I found a lot of good threads on the mouthfill on this forum, but one thing is still not clear to me: Is it performed only once before you reach "failure depth" and then your cheeks take you all the way down, or is it actually possible to repeat filling up your mouth/trachea even at greater depths?
Thanks for your replies!!!

 

[Kajojek]

It is done only once at around 30 meters. At greater depths its too hard to blow air into your mouth as the lungs are compressed.

 

[mortenkv]

I take just 1 big. At 25m-27m - that takes me to + 70m.
I think it is unnessecary to fill it up if you do it properly the first time - and it could put a lot of stresss on your lungs to fill it up (reverse packing) at depth.
But I never reverse pack at depths, so I have no exp on that
Morten

 

[demasoni]

I only do one fill before I hit RV so I fill once around 30m. That said, I know of others that fill later or more than once and some top divers claim they can bring up air at any depth. Go figure.

Most people I know just do one fill somewhere between 25 and 35m.

BTW, how's the FRC training going?

 

[polishpower]

How do you do a reverse pack when you have negative pressure in your lungs? is it the same way when you do reverse packs on land? Use your cheeks to suck out the air from the lungs?

 

[fflupo]

i pull my head back in the neck and do this comic sound mmmpf and keep the epiglottis closed and the soft palate open(down) and i do after almost every equalization just to stay on the safe side with some air in my mouth

it requires that you stay relaxed

the should be some info on eric fattahs website, he brought it into practice
.. i think


wolf

 

[demasoni]

polish power,

Good question, how do you bring up air once your lungs are negative?

When negative, I can blow out as hard as I can and bring my diaphragm up into my ribcage and try hard to exhale air into my cheeks. However, there is a point where I can't do this anymore and that's it. I practice by diving FRC volume or less and delaying the depth I fill my cheeks later and later. However, to avoid all this extra stress and work during an actual dive, I normally fill my cheeks before I hit RV and use that air for the rest of dive. So far, the lack of air in my mouth is not the limiting factor of my dives.

For me, using my cheeks to suck up air at depth would not work, way too much negative pressure for that.

Any other methods to bring up air once negative? I hear of divers who can bring up air at very deep depths. Care to share your knowledge?

i pull my head back in the neck and do this comic sound mmmpf and keep the epiglottis closed and the soft palate open(down) and i do after almost every equalization just to stay on the safe side with some air in my mouth

it requires that you stay relaxed

the should be some info on eric fattahs website, he brought it into practice
.. i think


wolf

Hi Wolf,

I'm a little confused but interested in what you are describing. Is this maneuver what you do after your final mouthfill and after each equalization on the way down? Why do you do it if your epiglottis is closed and you're not bringing up air?

 

[polishpower]

I do it in the same maner like you fflupo but when becoming very negative in the lungs you can't do a fill up of the cheeks anymore.

 

[JennyWren]

I've never been very deep, but I practice negatives in the pool. Basically if I make a sound (grouper call) I can bring up air when my lungs are very negative. I do reach a point where I can't bring up any more though.

 

[B-J]

Because of lack of experience I do several mouthfills on the way down. That`s mainly because I`m not very good at keeping track of how deep I am. Quite a few rely on their depthgauges to beep when it`s time. I don`t find it stressful to do many mouthfills. I just stop doing them when I can`t make it.
There is another technique to use when the normal mouthfill doesn`t work. It`s almost like packing through a snorkel, only the opposite way. You are just using your tongue to draw air up from your lungs. You have to do quite a few to get a full mouthfill For me more than 10. Just try to fill your mouth only using your tongue. This alot "stronger" than the normal mouthfill. Almost like comparing normal innhale with packing.
B-J

 

[fflupo]

i don t do a huge last mouthfill, for me it takes too much afford to dive with full checks .. will say i don t feel well with these checks like a hamster

i equalize and pull air out of the lung and with the movement of the head i get something like a strong syringe to withstand all this negative-pressure.
the air i pull up, i keep on top and rear of my tongue ready to push it towards the softpalate, the front bit of the tongue stays behind my upper teeth and kind of seals the system

if i would open the epiglottis all the air goes straight back in the lung :-(
so i hold it closed and suck the air trough it, no change to push it into the checks

i found it difficult in the beginning to keep the epiglottis that strong and in control, but it is important for me to keep it close and steel the air out trough it..

thats for far below RV

 

[Erik]

You can do a huge mouthfill at the surface before you dive, eliminating a lot of work before you get to 20 metres or so, where you could do another one for the rest of the dive.
I'll do it at the surface if I can't hands-free equalize due to cold temps or if I'm in a hurry (meaning I'll pinch my nose with a hand). If it's warm and comfortable and I CAN hands-free, then I use my diaphragm down to 20 metres before doing a mouthfill for anything deeper.

 

[haughki]

Any other methods to bring up air once negative? I hear of divers who can bring up air at very deep depths. Care to share your knowledge?

A lot of people have explained the basic process. Here's how I've practiced this dry:

Exhale all the way by using your muscles to push all of the air out of your lungs. Do this a few times: you'll probably keep getting very small exhales. When you absolutely can't push any more air out with your muscles, consciously relax your breathing muscles. Then, use the tongue and jaw to create a negative pressure space in the mouth; when you do this, you should not move or use your stomach or chest (diaphram/intercostal muscles); just relax that part of your body. I tend to drop my jaw and tongue at the same time. Really, all you need is the tongue: push/pull it down and into the back of your throat. I also make some sound; someone else mentioned this as the "grouper call." At the start, this is a nice thing, because this way, you know you're getting some air out of the lungs. Once you get it a few times, you'll have a bit of air in your mouth. You can just keep doing it over and over until you "pump" _all_ of the air out of your lungs. Be careful, especially at depth. Even in shallow water, in the pool, you can really stress the lungs and injure them.

 

[demasoni]

Thanks Haughki, the part about consciously relaxing my muscles after I expel all the air I could muster helped. I kept getting mouthfills of air to expel. It seems that relaxing the diaphragm then exhaling and then repeating acts as a pump mechanism on the lungs and keeps pushing the air out.

What is this "grouper call" I keep hearing about? Is this a commonplace term? I can exhale air just as well silently.

 

[JennyWren]

The actual sound isn't necessary but it does help people to identify if they are bringing up air correctly. I find that if I'm making the sound, I know I'm *pulling* air up with my mouth rather than *pushing* it up by exhaling with the diaphragm. I also find that when I'm negative, only bringing air up using the sound means that I have control over my epiglottis. I'm not at risk for opening the airway between mouth and lungs and having all that hard-earned air get shlucked back up into my lungs! It's like the only opening that allows air to pass through is my vocal chords, and if I'm making the sound the air is only going one way. It's easy to stop and start, so that you control exactly where the air is going, and where it will stay.

 

[haughki]

I also find that when I'm negative, only bringing air up using the sound means that I have control over my epiglottis. I'm not at risk for opening the airway between mouth and lungs and having all that hard-earned air get shlucked back up into my lungs... It's easy to stop and start, so that you control exactly where the air is going, and where it will stay.

I completely agree. Making sound during the reverse-pack keeps a nice, thin, controllable seal across the airway. Otherwise, it sometimes seems like I'm losing air back into my lungs. It also gives another sensation of how much air you're getting from the reverse pack. It even makes for a good underwater signal (to another diver).

The "grouper call" is the sound made by the air passing across the vocal chords. It's a low "oooomp" sound.

Hawkeye Parker