Functional Residu Volume - FRC - diving for beginners?

[Andrew the fish]

Your report on exhaling part way through the dive is very interesting. I had not run into that.
Connor

this one needs confirmation, I am trying to remember and I think there was only one dive with exhale at discomfort. But I remeber being surprised at the magic that exhale did. I will not be near pool for a few days, you folks will have to experiment with it, it may very well turn out to be nothing worth noting at all.

 

[byronq]

Great thread guys, sorry a little of topic... but I seeing spirometer prices in the $200.00 range here in the states. Are there deals out there ?
At my advanced age, 58 years young I would like to start measuring lung volume. Thanks in advance.
Cheers, Don Paul

Hi Don-
First off, thank you to all your contributions to our sport(s).

When I swam and played water polo at OCC, I went through some intense testing there (close to both of us). I bet you can find a way to do a spirometer test there. I'll look into it, and reach out if I find anything.

BQ

 

[Krusse]

Hi!

What would you say is a slow and safe way to explore and train "frc" diving in a pool with a max depth of 4 meters?

I come from a background with meditation, swimming, snorkeling and scubadiving and what draws me to freediving is the eased and relaxed way to be with the element. I discovered the other day that if I exhale some until I sink to the bottom of the pool my heart rate dropped to about 50% and I got totaly relaxed and calm. Almost meditative.

I love the ease and sensation about that and will explore it further. So, it seems like I am a candidate for "FRC - diving for beginners"?

Any suggestions?

Richard

 

[Andrew the fish]

Richard, welcome to the club. Before discovering FRC I always tried to pack as much air as I could, and I thought this is what makes my dives longer - more air! pack it! more! But the first time I tried relaxed exhale it was like "wow this is amazing". First it was in the pool, then I tried the same thing in open water, deeper and deeper. FRC isn't the mainstream of my diving, but I never pack anymore, relaxed inhale is all I do. To me, ease and calamity is more important, stretching lung till your ribs crack isn't relaxing at all.

Anyways, suggestions part. For a new fella I would highly recommend staying within your comfort zone, making freediving a pleasant and healthy sport. Get you adrenaline fix somewhere else, ok? I never had a black out (knock on wood) so I can't say how close we are when FRC diving, but keep in mind that if everyone says it is dangerous, then it robably is.

Pool practice is important part, to me anyway. 4m is excellent depth to begin with. Make your first descents very slow, have something to hold on to, so that you can control your descent.

 

[cdavis]

Hi Krusse, Welcome to DB

you sound like a very good candidate for FRC. Best background I know of is the thread below.

http://forums.deeperblue.com/general-freediving/78598-exhale-diving-average-diver.html

read it (its loong) and ask any questions you like.

Connor

 

[Krusse]

Thanks Andrew and Connor for your replies!

I have read the looong “Exhale Diving for the average diver” and it was most interesting and enlightening ☺

Some questions remains though:

1. The firs one is about safety and I am bit puzzled over the different inputs I get. I remember playing with “frc” as a child. We simply let some air out and lay there at the bottom of the pool watching all the activities going around. We were told to never hyperventilate but no one told us that letting the air out and sink was dangerous. Now as an adult I rediscovered this by chance and my pulse dropped from 60 to 30 bpm just by exhale some and standing on the bottom at 4 meters depth. In addition I got totally relaxed and present. I have been meditating regularly the last 10 years and I was surprised and amazed how I totally naturally went into this underwater meditative state of flow with no effort. Now, when first looking this up on Internet, “exhale diving” and “frc” is described as a very advanced and dangerous exercise that only should be done by advanced freedivers. Are we talking about the same thing here and should we actually warn people to never exhale and sink? Or is it a natural thing that could be done by everyone with some words of caution and having a spotter just in case?

2. As far I can understand from the thread there are two main dangers involved. One being the risk of getting a lung squeeze if exhaling to much regarding to the depth and not being used to it. The other one getting a BO because you don’t feel the need to breath in the same way as inhale diving. There are also difficulties with equalizing due to lack of air in the lunges when going deep. Correct?

3. From reading the thread my idea is to begin my own pool training with just exhaling a small amount to start with (maybe a weight to get negative), rest in static for a while and then a shorter length of swimming. Slowly increasing the amount of air exhaled, the time in static and the length of dynamic. Some say stay within the comfort zone and some say stay in static until the first urge to breath. What would you recommend?

Richard

 

[baiyoke]

I my view, to answer your question 1, look at your second question. The "exhale and sink" in itself is harmeless. But HOW deep do you sink, how fast, for how long, and how is your technique and mental state when doing it? That is where the advanced part come in: To prevent damage. Squeeze and BO is two of the major concerns in freediving, so yes, it's an advanced technique for those reasons. But not because of something "magic".

If you exhale completely, you can damage yourself in 2-3 meters! But that is when doing it wrong: Look at this thread for more info about squeeze and exhale btw http://forums.deeperblue.com/freedi...97623-full-exhale-pool-adjust-real-depth.html

Make sure you always have a freediving knowledgable buddy to monitor you every second of the dive.

2. As far I can understand from the thread there are two main dangers involved. One being the risk of getting a lung squeeze if exhaling to much regarding to the depth and not being used to it. The other one getting a BO because you don’t feel the need to breath in the same way as inhale diving. There are also difficulties with equalizing due to lack of air in the lunges when going deep. Correct?

In general correct, but about the BO risk: You do get strong urge to breath also in FRC. I've had problems getting answer to why BO is more easily happening, but the closest I came was something like: "You got less O2 in lungs and in general in the system, so before CO2 has risen high, you could run out of O2, and the reason for this is that the lungs are better at storing O2 than CO2". (Just writing it now, I realize that the lower CO2 around BO-level will be a factor also because of the Bohr-effect, but nevermind). Many people seem to believe that CO2 is higher on FRC, and that's why DR is kicking in faster, but from asking here on DB, to me the answers point in the direction of a lower CO2 level... but whatever it is, CO2 is at least lower in absolute numbers around the time of BO it seems. CO2 doesn't have the same time to rise, as when on full lung. In short: It's my impression that the FRC physiology is not very well understood (if I remember correctly http://forums.deeperblue.com/general-freediving/96075-whats-going-exhale-frc-bo-co2-safety.html NOTE that the graph in the 3. post is not correct! however, but I can't edit and write that now )...

About the third question I don't have a recommendation, depends on what the purpose is with doing the excercise...

 

[Krusse]

Thanks baiyoke!

The purpose of my exercises is longer and more enjoyable recrenational dives by training and using exhale dives with maintained safety. I am also curious about exploring it from a meditative point of view. To be in the flow under water.

Richard

 

[cdavis]

It all has to do with how much you exhale in combination with how deep you are going. Full forced exhale and you can get squeezed in a 4 m pool. It happens very fast and you won't see it coming. Full forced exhale statics produce some funny effects and more than a few B0s have been reported. Exhale 1/2 lung and it is a whole different thing. It still takes practice, because the bodies reactions feel pretty different, and inital c02 level seems to be critical to long dives, but DR kicks in early, it is very comfortable and, in my opinion, very resistant to B0. Depth is till tricky. At 1/2 lung, somewhere around 20 meters you will be getting into squeeze territory at first. Again, it happens fast and you may not feel it coming quick enough if you are sinking fast.

My interest in exhale diving is the longest possible comfortable dive in moderate depth. It is a great technique for that, just take it slow, and have a good attentive buddy as you are exploring the technique. You will probably find that is is a balance of initial c02 level, lung size, static length and ability to be relaxed in breathup. All can vary and the optimal will probably be different for any given individual.