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Herbert did 95 constant!

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
Eric & others,
What about contracting your diaphragm to reduce the size of air on the descent and make yourself less buoyant? Is this possible?
don
 
Alun wrote:
> the 'FRC' limit is around 100m on half a lung... ok, is that really such a great leap forward from full lung diving?

Very good question. First, several comments.

In my case, 3.5L / 10.9L = 32.1% of max lung FVC w/packing
Or, without packing, 3.5L / 8.05L = 43.4% of max lung FVC
(so, this is more like 'third of a lung' diving)

Personally I think 120m is probably possible in CW on a full pack, and maybe something close to that on an FRC, so we are back to Alun's question; if you don't 'gain' that much in depth, then is it even a step forward?

I say yes, in many, many ways.

First of all, for me diving isn't about records, it is about repetitive recreational dives. I have a goal of one day doing 60m 'fun' dives, no line, just exploring or 'soul' diving, over and over. I was working towards that goal this summer and by the end of the summer I was doing repetitive 50-53m 'fun' dives with no line, along the bottomless walls at Whytecliff and Ansell, hunting for giant cloud sponges. A recreational dive is a dive which is easy enough you would be confident doing it alone, even though I don't dive alone. However, DCS is a major problem. I was taking 8 minute intervals between dives, which is a major waste of time, and is it even enough time to avoid getting bent? Not to mention I can't stay warm forever, and especially in winter, such a boring interval sucks. If the depth were 60m or more, the interval would increase by far. In the case of Herbert's depth, the interval is a whole day, or, if you carry around 100% O2, maybe half a day. BORING.

So, when we say an elephant seal can dive to 1800m, what we really mean is that an elephant seal can dive to 1800m, over and over, with 2-3 minute intervals, with no descent line, as it goes down to 'look' for things (i.e. food).

A diver who goes to 100-120m on a full pack can only do it once, or maybe twice, in a single day, otherwise he will be at great risk of DCS. Let's not forget that each year at the world spearfishing championships, one of the big name favourites such as Pedro Carbonell or Alberto March always seem to pull out with decompression sickness, and that is from 40m dives! So, to say that humans can dive over and over to 40m isn't even accurate; they get bent eventually.

So, going back to comparing a 100m inhale diver vs. a 100m FRC diver. The inhale diver is risking his life on every dive. Remember that Stefano Makula blacked out at the bottom at 100m on a no-limits dive which lasted for much shorter than a CW dive to the same depth. The 100m inhale diver not only risks blacking out 'down there' from O2/N2/CO2, but his mind is foggy, he feels anxiety and other symptoms of narcosis, and he hopes to god that he will make it up without getting bent. The dive is torture to say the least, and the 100m inhale diver can't wait to get it over with and get back to his girlfriend. Is that freediving? Maybe for you, but not for me.

The 100m FRC diver is a different story. He isn't risking his life down there. His mind is clear on the whole dive, no feelings of doom caused by narcosis---no narcosis at all. He isn't afraid of getting bent on the ascent, in fact he could go right back down after, and maybe he will. He sinks during the whole descent and doesn't go through a brain-popping 50 packs before the dive. He isn't afraid of blacking out from packing before the dive. And, most important to me, he can do 60m 'fun' dives over and over with crazily short intervals, enjoying every dive, looking at the interesting marine life which lives below 50m. All these contribute to a psychology where he LOOKS FORWARD TO MAKING his dives, even if they are pushing it at 100m+. He wants to 'go and see.' Unlike the inhale diver who is dreading the torture. For those of you who have done 60m inhale dives and enjoyed it, trust me, things get much worse near Herbert's depths.

The FRC diver's only worry is the simplest and most ancient worry of freediving; simply running out of O2. In the worst case he suffers a B/O near the surface on his 100m dive. Been there, done that. Not very healthy, but not a really big deal, compared to a B/O at the bottom like Makula who barely survived, or DCS like Benjamin Franz, crippled for life.

After my deep dives and record attempt in 2001, I told myself I would never go for another 'record' unless I could enjoy the dives, because I sure as hell wasn't enjoying THOSE dives (even watching the video gives me shivers and twists my stomach).

So, the morale here is that 'depth' is more than the depth one person can make on a single dive, risking his life in countless ways, playing 'russian roulette' and only being able to do the dive once in a day.

I began the FRC program so I could do 60m fun dives over and over. I'm just getting started, but maybe if I eventually reach fun 60m dives, I would be in shape to do a much deeper dive which I would enjoy. If so, then I might show up at a competition. That is my attitude.

To me:
FRC = fun, safe, can be done repetitively
Max Pack = torturous, unsafe, cannot be done repetitively

Depth, to me, is the depth you can dive to, while enjoying it, while doing it over and over, like our marine friends.

So, is FRC diving a step forward? You decide.


Eric Fattah
BC, Canada
 
i can definitely see the benefits of this type of diving, and it makes sense in many ways.

just as deep inhale diving may be russian roulette with regard to narcotic effects, i also consider deep FRC diving to be russian roulette with regard to lung squeeze. there are not likely to be many warning signs before a deep water BO during an inhale dive. equally there are not likely to be any warning signs before suffering lung injury during an FRC dive. at least we have systems that can retrieve divers from depth in the event of BO. we have nothing that could save a diver from serious/fatal lung injury at depth.

step forward for recreational dives?.... quite possibly? but only for top freedivers who are already accumstomed to deep inhale diving. then we face the problem of less exprienced freedivers also wanting to follow the same path, but who may end up progressing faster than their level of adaptation allows.... with inevitable consequences.
step forward for ultra deep dives.... i'm not so sure personally.

it must be extremely important to progress incredibly slowly with this kind of diving because each metre of an FRC dive is equivalent to many metres of an inhale dive, in terms of lung pressure. the other thing that we shouldnt forget is that during nolimits, it takes around 1-2mins to reach max depth... which gives time for blood to actually move into the thorax. during FRC dives you reach the 'high pressure' depths much more quickly - giving less time for the shift of blood to occur and hence equalise pressure....
 
very interesting!

I have a few questions about all of this.

First, since your not inhaling, and packing, does the size of your lungs become unimportant- a person whith small lungs could compete with some one like Robert Croft on the same terms??

Second, do you still get contractions to let you know when your getting close(r) to running low on air?? Do you get any warning signs??

Third, is your bottom time more limited since you've brought down less air to start with??

Fourth, how do you train for this, all exhale dives to the bottom of a pool along with exhale sprints underwater???

Fifth, how much time do you need to recover on the surface?? There has to be some time limit to reoxygenate all of your cells, is it 2 minutes or 10 minutes, and how would you know??

Finally, how deep have you been able to get down so far Eric?? Have you noticed that your bottom times are shorter, if so by how much??

Interesting ideas that make you think.

Jon
 
I don't have time to answer all these questions thoroughly, but here are the main points.

The most important idea is Alun's worry about the squeeze. It's the obvious question, but a quick analysis shows it's not a problem at all. In fact, FRC dives may be safer than inhale dives as far as squeeze go.

First of all, you must understand a person's 'air equalizing limit.' The air equalizing limit is the max depth a person can equalize to on air. At that depth, they have a certain volume of air left in their lungs, whatever it may be, let's call it X litres. So, whenever this person reaches his air equalization limit, he has X litres of air in his lungs. It makes no difference if the person did a negative pressure dive, an FRC dive, or an inhale dive. In each case, he can dive only to a certain depth before he is stopped by equalizing (assuming he has enough O2). Each time, he has precisely X litres of air in his lungs, and each time, he experiences the same degree of squeeze.

So, given that many divers today dive to their equalizing limit, especially on negative pressure dives, there would not be any reason to expect a sudden jump in lung injuries on FRC dives. How do you know if you are going to deep on a negative dive? You take it in stages. Go to 8m, come up, see how you feel. Coughing? Blood? If everything felt fine, try 9m. Likewise, while you are down there, you do get a vague impression of the squeeze, in terms of discomfort.

So in that sense, you will not get any more squeezed on an FRC dive supposing you stick with air to equalize with. The approximate depth limit for air equalizing on FRC is about 40m, the classic spearfishing limit.

Next, Alun comments that the squeeze will occur faster on FRC dives. This is true, but the squeeze occurs much more slowly than on negative pressure dives which ultimately result in the same degree of squeeze. Further, inhale dives can be even more dangerous. The new theory, proposed by Rudi and gaining widespread acceptance, is that packing pushing blood away from the lungs, and delays the blood shift dramatically. This is why some people have noticed a greater tendency towards squeeze injury at depth, while diving after packing at the surface. With FRC dives, there is no packing, so that effect doesn't occur.

If the FRC diver wants to go over 40m, then he must adopt complicated water equalizing methods. How many recreational divers use water equalizing? This is more in the realm of pro diving. The people who do it know what they're doing, because anyone with common sense would realize that if you DON'T know what you're doing when you flood your sinuses or suck water into your mouth, you could drown. So, only experienced divers would venture into the 'water equalizing' world of FRC diving over 40m, and they would be much more prepared for the risks to follow.

So, I don't think FRC diving is russian roulette at all, when it comes to lung squeeze.

Further, concerning the 'fatal lung injury at depth' argument, this has yet to occur. Perry Gladstone has experienced extremely severe lung injuries at depth, to the point where he nearly suffered a secondary drowning at the surface, and he reported that while 'down there', he was fully functional and easily able to swim back to the surface. So, even if the diver DID suffer a lung injury down there, in all likelihood he could still function and ascend.

One last comment about the squeeze: Remember that you only need to find out your squeeze limit once. The average diver knows his negative pressure diving limit. It's not like every negative dive is a 'russian roulette' in terms of 'what's gonna happen this time?' He has been to 8m before, he knows that if he follows the same warm up routine he can reach 8m again. Likewise, once the FRC diver has comfortably gone to 30m, he knows that with the same warmup he can return to 30m. Going any deeper requires the same attitude as going for a 'negative pressure personal best,' i.e. a gradual and common sense approach.

I'll get to the other questions soon.


Eric Fattah
BC, Canada
 
Apart from the physiologic considerations that have been exposed very well, the emotional considerations from the Eric post call my attention. I believe that the apnea is to enjoy, it is not only a run for a tag and a quickly return to the surface. What most I love is to be underwater for a long time. For this reason, my brother and me, love the hangings, in fact, in an occasion my brother took about of 3 minutes in a Hanging at 38 meters, and a total time of 4 minutes, it was longer than expected, so I went down to see what happened, and when I arrived to -30 I saw him calmly looking at the abyss, I moved the line and he turn his face up, looking at me, I made him signs to ascend and he began to make it, at 5 meters He point out to my that he could not finish and the rest of the road went by my fins, at surface he had a small LMC. When I asked him what the hell he was doing , he told me that he ecstasy looking at the reef and heforgot the time. Thats what I call freediving , I am not as ambitious as Eric, but I dream of the day in that I can make 4-5 minutes of bottom time among 40-45 meters.
 
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From Eric F
Your non-lung O2 stores were seldom stressed in your years of inhale diving, because you always had high oxygen at depth, due to the pressure. Now, without much air in your lungs, your blood & muscles become hypoxic even at depth, and your body adapts accordingly
Am I missing something here?.. apparently. Watching my saO2 on an empty lung apnea and comparing it to a full lung apnea I notice 2 or 3 things right away.
1. my saO2 drops to very critical lows, along with the bradycardia in very short time.
2. the discomfort is not near that of a full lung apnea and it is easy to reach the point of LMC or near black out.
3. with a full lung apnea it is impossible for me to attain the same saO2 numbers as with an empty lung apnea and the discomfort is terrible in trying.
So, just how healthy can this repeated empty lung diving be? What am I not understanding?
Fred
 
Is not for me, but I give you my opinion.
He's talking about Oxygen at depth, and you are measuring SpO2 (the right term) at surface. Besides the SaO2 is not the same as PaO2, it's changed by pH, 2,3 DPG, Temperature.
At depht we are hyperoxic in a full lung dive.
Of course is easier to get a BO, but I you train an progress slowly your body will adapt to that low lung oxygen, and use the reserves (Myoglobin) and anaerobic metabolism. I never tried a PB with FRC, but I'm thinking seriously in the theory
 
When you B/O from an inhale dive, your blood oxygen dropped so low you lose consciousness.

When you B/O from an FRC dive, your blood oxygen dropped so low you lose consciousness.

But, there were differences DURING the dive. In the case of the inhale dive, you had high oxygen levels until the last 20m or so, when suddenly the hypoxia hit you.

During the FRC dive, your O2 level decreased gradually during the dive, allowing more time for your body to defend itself from hypoxia.

The adaptations take place during the times where your body is stressed. In the inhale dive, your body was only stressed in the last 20 or 10 metres (or even less if it was an easier dive). During the FRC dive, your body was stressed for a longer part of the dive, just like seals & whales.

Because the body is barely stressed during an inhale dive, people find that they don't improve much by just diving. In the beginning, they improve a lot due to technique, relaxation, etc... but then they reach a plateau for years. Their dives today, are just as long as their dives a year ago. Not suprising, since their body is not really stressed during inhales dives -- certainly not stressed during recreational inhale dives. So, they are forced to do some activity which DOES stress the body, such as hard running, swimming, or other aerobic or anaerobic exercise. They improve at their diving, because those activities DO stress the body, but they don't stress the body in exactly the correct way, because they are not the same activity as diving. In sports we are told to stress the body in the same activity as we plan on performing in. If you want to swim fast, you train swimming, not running.

However, in inhale diving, there is very little stress to the body, so you are forced to use alternate methods of hard training to improve.

With FRC diving, there is enough stress to the body that all you need to train is FRC diving. Because you are training exactly the correct activity, the adaptations which occur are the best ones possible.

The seals and whales became good at FRC diving by practicing FRC diving. Remember that seals and whales do not forcefully exhale before going down, they simply let their lungs fall to the neutral point, which is the definition of FRC.


Eric Fattah
BC, Canada
 
that makes good sense to me.

as i said before, if i make a genuine passive exhalation, leaving me with my in-water FRC, then i find that my lung volume is very nearly RV - i can't even do a proper mouthfill at the surface! to me a passive exhalation is almost the same as a forceful exhalation. does anyone else find this to be the case?

if you have to 'hold back' on the exhalation to keep about a third lungful (for e.g.) then the thing that would concern me is that you don't store the exact same amount of air each time you dive.... i can see this being a potential problem when diving close to your limit.... have i explained that point clearly?
e.g.
you perform a max effort dive to depth X with a 35% lungful - and surface clean but close to your limit - fine. next day you try for X+1 and dive with a 30% lungful... because you're unable to get that optimum 35% (or whatever it may be) each time.... result... BO. (you don't have this potential problem when doing inhale dives because you take almost exactly the same amount of air with you on each dive.)

of course, one solution to this problem would be to perform the passive exhalation sitting on a diving platform - so it is a true 'surface FRC'. you would then have the same lung volume for each dive.

does this issue concern you Eric?
i'm not deliberately trying to 'pick holes' in this idea at all. :) i think this is a very interesting discussion and it's good for us all to talk about it.
 
Just a little incision here with a website for people to refresh or familiarize themselves with the different lung terminology: FRC, RV, TLC etc.

http://www.spirxpert.com/indices15.htm

The whole concept of FRC diving is fascinating.

Adrian
 
It's true that in the beginning, it is a bit difficult to start the dive with the same volume of air every time. However, in the beginning, the diver is not usually limited by oxygen anyway, but by equalizing. Even after a few sessions, it becomes easire to start the dive with the same air each time, and remember that you know how much air you started off with by the depth at which you reach your 'air equalizing limit.' So, if you notice that your mouthfill was more difficult, or that you ran out of air to equalize at an earlier depth, it usually means that you started off with less air than usual.

However, remember that in FRC diving, the point is to store most of your O2 in blood & myoglobin anyway (and creatine will store energy too). In that sense, the lung volume isn't very relevant except for equalizing purposes. Especially once the blood and myoglobin have adapted and become the primary O2 store, the lungs become less and less important, and a 10-20% difference in the starting lung volume shouldn't matter much.

In my mind, the danger would be for a beginner, who is neither limited by equalizing nor by O2, but by squeeze (even on air). Such a person should work on negative pressure dives before even beginning FRC diving, but if he were too ambitious and started FRC diving before reaching his air equalizing limit on negative dives, then he could be at risk to a lung squeeze due to the somewhat 'random' amount of air he starts each dive with, since he is not yet proficient at sensing the correct starting air volume.

In that sense, as long as a person can reach their air equalizing limit on negative dives (without running out of O2), then they should be fine to start FRC diving as long as they stay away from water equalizing. If they can already reach their air equalizing limit on inhale/packing dives (without running out of O2), then their journey into the FRC world would be even more safe.

Yet, in all cases, I would expect to see a dramatic reduction in depth capacity in the early stages. Few people are willing to take five steps back before they can take six steps forward.



Eric Fattah
BC, Canada
 
I did my pool training today in FCR, I know it will be better real diving, but I can't (no ocean or lakes nearby). It was more difficult than usual in terms of Oxygen, but my technique was better (less bouyancy?). The best effect was in dynamic without fins, I felt so streamlined.
I'll give a try to the theory. It's logical for me
 
Tried today

I tried this FRV today and I can like Alun say that when I lay in water I probably get around 2.5-3L (somewhere between RV and FRV out of the water) on a passiv exhale.

I could go to ~23m before I hit my limit with this volume of air. Maybe I could have partly filled my mouth but my chest felt very compressed so I didn't dare to go deeper.

I think this is a very good way to train equalizing (+ if it makes the body adapt like Eric mentioned it's even better) and I think it's far safer than emty lung diving since the bloodshift goes slower.

This type of training can probably be done in the pool to and I guess the training will be more hypoxic than with full lungs.

I don't think I 'll ever be able to dive really deep with this method (since I don't plan to equalize with water) but it will be interesting to see yours and your buddies progress Eric.
 
Please! Anyone who tries pool training with FRC, you MUST have a buddy carefully watching.... The urge to breathe is not the same with FRC swimming, and the breathe-up must be different. You must start the swim/dive with lots of CO2. This means an extremely slow breathing rate before you start -- no fast breaths. I like to inhale, hold for 10 seconds, exhale, inhale, hold for 10 seconds, then inhale-exhale, go. Even this may be too fast. Perhaps I will try holding for 20-30 seconds on each breath. If you don't start the FRC swim/dive with enough CO2, you will have little or no warning and suddenly B/O! Be careful please.

One method could be to inhale, hold until you feel an urge to breathe, then exhale-inhale-exhale, go.


Eric Fattah
BC, Canada
 
Hi Eric,
interesting reading on FRC diving/training! I am not yet ready to give up inhale diving though ;)
I'm pretty sure that even Seb who has been doing this longer then anyone still does some of his PB dives on full lung, not FRC. I know his dynamic (200m) and no limits he did full lung. I don't know about constant, but I guess that's really what you have been talking about. Should find out what his PB is full lung, and FRC ?

I do see huge benefits as far as training is concerned.
I have already been doing empty lung dynamic training for a while. For me I find it is easier to get much more training done in a shorter period of time. I have lousy CO2 tolerance so have found with the empty lung training I can reduce my rest interval. Also don't have to put up with as many contractions, and at same time getting more hypoxic. (Doing much shorter distances of course, and with a buddy.) :duh

With what Seb found out about cutting out Aerobic exercise, and increased hematocrit. My question is this, if he were to start doing Aerobic exercise again, do you think it would go down, or stay the same ?
I guess what I'm leading up to is do you think there would there be any benefit in training in cycles? ie 1 week to 1 month?, no Aerobic exercise, FRC/empty lung training. Next cycle FRC/empty lung training + exercise........

When I do train for fitness, I do find it helps my freediving. Not always to increase PB's, but makes diving easier, rest interval shorter, able to dive longer periods in ocean etc. Also for a lot of people I know that freedive, they also enjoy many other sports. Having to give up more general fitness in order to improve in freediving may not always be an option.

Also roughly how quickly would you say your levels went up after you cut out Aerobic exercise ?

Cheers,
Wal
 
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Eric seems to be the ambassador and guru of FRC diving so I guess this post is directed at him...

In July, trusting your theories and supporting empirical evidence I decided to cease all aerobic excercise, and create a blood-developing hypoxic programme. I entirely agree with the principle of FRC diving - that blood & tissue store O2 more expediently than lungs, & am excited about how this affects MDR and buoyancy. However my fear is always that my programme is not efficient or specific enough. Therefore I would greatly appreciate your confirmation as to whether the following contribute to an effective programme. (To save tinme you can skim read and give each a grade of effectiveness from 1 - 5)

- Exhale Pranayama (Inhale:exhale:hold in ratio of 1:2:4) Combines the yoga breath control with constant state of hypoxia.
- Hypoxic running (eg inhale 6 steps : exhale 12 steps) Constant hypoxia with physical work.
- RV apnea tables. Focussing on short recovery time so as to maintain hypoxia.
- RV statics at depth. To increase chest flexibility, train MDR etc.
- Diet: designed to build blood. An assault on red meat, especially liver, iron pills and multivitamins. Low SFA's, high protein:carbohydrate ratio, much vege and fruit. I long ago took your advice and saved my adrenals from caffeine, alcohol and monosaccharides, although I still gorge honey (that's Umberto's advice, and besides honey is mostly frutose, and has antibiotic value).
- Suit. I train and dive only unassisted, & have had similar problems to David Lee when freefalling sans suit - drag is prohibitive. Swimmers such as Thorpedo wear 'sharkskin' suits that have the best known hydrodynamics, without affecting buoyancy or flexibility. Surely this is the way forward for freediving also?

Best wishes for your FRC training, and thanks again Eric for sharing your wisdom and experience with us all.

profondo, Will
 
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in lack of work in the office, I came up to this old thread...

Will's quest for an effective pgm 8yrs before the hectometer!
 
I remember those days! I didn't have a clue, and didn't find one until over a year later.
 
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