Signs of an imminent BO?

[Rf2]

Hello, I am very interested in apnea at the moment and have started doing dry breath holds. I have reached 3 minutes 25 seconds, and though I have gone through quite a few contractions, I feel confident I can hold it longer but am wary of the dangers. I did some searches on the forum and though I found many threads containing the various keywords I entered, I did not see a specific answer to my last question. Thanks for any response.

1) From reading these boards, I have seen that dry apnea on a bed (so as not to hit your head during a BO) is safe. However, I am still uncomfortable reaching a BO and do not wish to experience it, do you know of any tell-tale signs of an imminent BO while holding your breath? I have read that shallow-water blackouts show no signs but I am not sure about a regular BO.

2) Other than this forum, do you know of an online source that has compiled information for a beginner like me? I have looked at the beginner sticky, and have followed some broken links, but I have not found any one page aimed at beginners with in depth information on training techniques such as breathing exercises before a run and tips on packing. If you know of a thread on this board that contains this source however, and I apparently missed it during my search, I would appreciate a link. Don't get me wrong, this forum is absolutely a great source for this sort of information, however I was looking for a more condensed version. If there isn't one that's fine, I will continue browsing the forum as I am doing now.

Oh and I guess a quick question for packing: I usually do slow deep breaths in and out for 5 minutes, each lasting 5 seconds each. Then I exhale completely to the point where I almost feel like coughing, after that I take one deep breath, followed by quick packs (I don't pack as much as I technically could because I fear possibly straining my lungs). How does that technique sound to you?

PS: It seems I do my best when listening to a calming song (All I Need by Air is what i listen to). What do you listen to if you listen to something?

Thanks again for any info you might provide!

 

[AltSaint]

Hi Rf2

For both types of blackout there are symptoms you can recognise, but often they are quite subtle. Also, after a full blackout, most people lose memory of the last few seconds before it happens, and so can't recall what they were feeling.

A few tips though. You may feel as though you have passed the struggle phase and have a 'fresh wind'. You may feel time speeding up suddenly. Sounds around you start to sound different in an inexplicable way. It tends to be different for different individuals, and I can only explain what I have felt when close to Black-out, not when it has actually happened.

Some useful websites:

http://www.freedivecentral.com/

http://www.britishfreediving.org/
http://www.apneamania.com/code/index.asp

If you feel that you must pack, then I'd advise you do it slowly rather than quickly, especially if you are standing up for any reason. Otherwise you may have syncope.

I strongly suggest listening to Marillion for breathholding.

 

[MBanks]

ok, so this isn't to do with the black out part of the thread but I thought I'd mention the music side of it

I like to listen to minimal ambient and some soundscape artists if I want music on while doing a dry static. Some of the artists I like are:

Brian Eno
Labradford
The Dead Texan
The Four Carnation
Pan Amercian
Harold Budd

And the list goes on...Think I might make Dry Static Music Thread

Martin

 

[naiad]

Also, after a full blackout, most people lose memory of the last few seconds before it happens, and so can't recall what they were feeling.

That happens to me, but then the next day I regain the memory. Immediately after a blackout or samba, there are between 30 seconds and 2 minutes that I can't remember, but the next day I can remember what happened right up to the point that I blacked out.

You may feel as though you have passed the struggle phase and have a 'fresh wind'.

That happens to me. There is a point where I don't want to stop, because the intense urge to breathe fades away or becomes a nice feeling, and then I know I am very close to the limit, or it may already be too late.

Lucia

 

[Sergiu]

good choice of song Rf2! that sonf from Air is among the top on my list too.

coming back to BOs, i have read a lot of these threads on Deeperblue and one conclusion i came up with is that you cannot find a standard patern with sambas or BOs...you will know for sure only...afterwords! My advice is to do a personal best only with somebody around you then use that time (say 3.25min) as the base for static tables which are normally at 60-70% of your personal best. This way you should be safe from problems - BOs come when you push your limits.

Also i figured out myself that you wont make big jumps in performance, if you are at 3.25min mark now, dont push a 4 next morning, rather "visit" the 3.30 several times and beyong before going higher.

serge

 

[XabreTooth]

Let's shift our attention to dynamic:

How would one know he is approaching BO while swimming under water? Does that happen without warning, too? Or do you go through a struggle phase first?

I've been doing quite a few underwater laps in the pool lately (probably around 500-1000 lanes this year), and sometimes I feel nervous that I'm pushing into the red zone. Actually I barely feel pushing myself at all, but could be I'm not reading my body signals properly..

At present I do sets of 15-20 dives, and I'm comfortable with swimming underwater for app. 1:20 (so individual dives are of that duration). Occationally a sloppy breath-up forces me to push through the last 10-15 secs, to still cover the distance to the end of the pool..

So. How much 'fighting' can you do in dynamic, and still be in the safe zone?

tx.

 

[Sergiu]

Xabre,

My personal experience, as i notice after reading your entry, is pretty much the same level of performance with you. Yet i had sambas both in static and dynamic though my friends tell me that BOed for a few seconds which is probably true - i dont have a recollection of that part anyway. In static, I was aware I push it a bit far but was hoping I will not samba, while on dynamic I thought i am okay, came out and had difficulties to stay afloat. it came from nowhere.

My point is that on dynamic the samba/BO will hit you faster as the oxygen depletion will be greater due to movement. I never went right into a BO in dynamic but it's doable with just one more stroke too many and there are no distinct signs at least not that you can count on as the red light starting to beam.

serge

 

[Adrian]

This is a very interesting thread, I'm moving it into the "Safety" forum.

One of the things I've read here is that some people experience a tingling on the fingers, or start to have tunnel vision just before blacking out. However, my feeling on this is that it will be different depending on the individual.

 

[naiad]

I haven't ever experienced a BO while doing dynamic, so I don't know what would happen. I have felt close to the limit, but I don't know how close I really was, as there has never been any LMC.

There are no definite warning signs for me, that is why I don't know how far to push myself with dynamic.

 

[tylerz]

One of the things I've read here is that some people experience a tingling on the fingers, or start to have tunnel vision just before blacking out. However, my feeling on this is that it will be different depending on the individual.

I have heard this often, yet I have never noticed that I was having tunnel vision before a BO. I have had a number of sambas while under normal dry conditions, unrelated to freediving, where my vision faded out completely. Once while doing Bikram's Yoga and twice while heading to the toilet in the middle of the night.

However, I seem to lose memory, or stop storing memory, 5-20 seconds before a strong samba or BO. Exactly what is experienced before, during, and after critically low oxygen levels, I believe is very specific to the individual. Somebody recently claimed the following day they suddenly remember everything prior to BO. I generally drift into samba and BO without in any way suspecting that I am. In all cases in the water, large or small degrees of samba/BO, I have no memory of some number of seconds before or of anything out of the normal happening prior. Of course there is the memory of things getting difficult, but that happens often to me when pushing myself and in the cases of samba/BO, it occurs long before the samba/BO; it is no different in sensation as far as I have been able to detect so far.

As far as finger tingling, I believe that is common for people that have a significant blood shift. So, for those having a BO and associating finger tingling with it as a sign, it suggests they are not having vasoconstriction at the extremities throughout the apnea. Whether any, or a significant number, of apneists have vasoconstriction during static and dynamic events is still left to be demonstrated, I believe. Anybody heard of any research on this?

So, what signs prior to a samba/BO have I discovered for myself personally? None, so far. However, recently I have found that I am more consciously attempting to sense what happens in my body during freediving activities. I am used to just diving, sensing my surroundings, and find my mind does not feel too inclined to sense what is happening internally. This gives me hope that I may find some internal experiences that suggest low oxygen.

 

[naiad]

Somebody recently claimed the following day they suddenly remember everything prior to BO.

That was me.

As far as finger tingling, I believe that is common for people that have a significant blood shift. So, for those having a BO and associating finger tingling with it as a sign, it suggests they are not having vasoconstriction at the extremities throughout the apnea. Whether any, or a significant number, of apneists have vasoconstriction during static and dynamic events is still left to be demonstrated, I believe.

I think I do. I go pale for a long time after a static or dynamic session.

Lucia

 

[X-Fins]

Hi !! my cent in the discussion:

i only have experienced one BO. I don't remember the 30-45 seg before, in fact i don't remember my will to get the surface, but i left the bottom of the pool (5-6 mts) by myself.

When i push myself in Dynamic i can feel a metalic flavour in mi mouth,some one know why this metalic feeling??

Best regards, Luis

 

[XabreTooth]

For how long do you push yourself?

 

[X-Fins]

Not too much 50 mts in DNF and about 80 mts with mono.

 

[XabreTooth]

I mean: Should i fear a black out swimming under water when i'm barely entering the unconfortable zone? To achieve a personal best in (dry) static, i need to endure almost 2 minutes of discomfort..

 

[naiad]

When i push myself in Dynamic i can feel a metalic flavour in mi mouth,some one know why this metalic feeling??

There have been some discussions about that. I have noticed a metallic taste when I push myself in static, and also when coming round from a blackout.

I mean: Should i fear a black out swimming under water when i'm barely entering the unconfortable zone? To achieve a personal best in (dry) static, i need to endure almost 2 minutes of discomfort..

It is different for different people. I don't know for sure myself. I have blacked out in static without any discomfort, but this was because I did something wrong, or different from usual.

 

[Sergiu]

we are back into the murky waters...the transition between full control - disconfort yet in control - samba -BO. I am afraid you will probably have to bump into a samba or BO once or twice to know your own limits and add a safety margin to them. From there you can push further bit by bit after at least 2-4 weeks of training. An example, I was reaching regularely 4 min (every training) in statics and had a PB of 4.35 so i tried a new PB going straight for a 5 min... at 4.30 in full control, 4.45 still there ( i say it, by buddies are not so sure! ) at 4.55 i came up with a severe samba which apparently was a BO though i stil claim i remember everything but was not able to control my movements nor to say "i am okay" for some 20 seconds. So, my disconfort zone was 3.30-4.30m and 5min was already the risk zone. Same with dynamics, i never do over 65m in DNF without safety on watch and only after a few good attempts i put raise the bar up a little. i hope it helps.

serge

 

[naiad]

we are back into the murky waters...the transition between full control - disconfort yet in control - samba -BO. I am afraid you will probably have to bump into a samba or BO once or twice to know your own limits and add a safety margin to them.

That is what has happened to me. I have now done much longer times than those which have caused me to samba or BO in the past. When it has happened, I have always tried to work out the reason, so I can avoid doing the same again. It is almost always because I have done something different from usual, or which I am not used to.

 

[Merlin]

I mean: Should i fear a black out swimming under water when i'm barely entering the unconfortable zone?

I have blacked out way below my personal best simply because I did an improper breath up right before. So go by feeling/instinct and dont push it just because you have done it before. Thus why a buddy must always be there at all times.

Oh yeah, and I didn't realize I had blacked out.... my buddy had to convince me after I came to that I had actually blacked out. I dont remember about 30 seconds before the BO.

 

[naiad]

I have blacked out way below my personal best simply because I did an improper breath up right before.

Same with me. I just need to do something slightly different from usual, that I am not used to, and...