Confused about exhale and Black outs.

[Danny.c]

I am a very keen spearo and I really only dive alone in the shore ,now and then I head out to reefs etc.
My diving is very patient and slow as I don't ever want to black out,but my bottom times are increasing at an alarming rate through the practice of apnea,so I need clarification.

I have searched far and wide on the googlys and this forum But I can not get a straight answer to this simple question or I see answers that just don't make sense like-"you don't exhale you inhale first as you breech the surface.Now how does a diver inhale dive,return to surface with a full lung of air then inhale.WTF!!.I see this comment every were,it does not make sense.-To my question.
When do I ex-hale?? Is it before I breach or do I ex-hale on the surface,I really need to prevent any chance of black outs occuring ,as I don't have a dive buddy to rescue me.
Cheers Dan.

 

[Jo_duiker]

...I'm not a spearo and I'm a lousy breathholder, but I do know that in order to be able to inhale when you surface, you must first exhale, no matter how little that is. You can exhale before reaching the surface. Exhale in the last 2-3 m before your mouth gets above the surface. Only then you will be able to inhale directly at the surface.
Another possibility is that you might have misunderstood or that the answers you got were not clear. In my AIDA 2* course, I learned this: when you surface (after static, dynamic, cwt): exhale but do not empty your lungs entirely: make it a very fast, but shallow and passive exhale and then inhale rather fast, actively and deep and hold that breath for 1-3 seconds while "trying to breathe out" against your closed mouth. Repeat this 2-3 times. This is called recovery breathing. So, the focus is on the inhale being active and deep and not on the exhale which is shallow and passive. After the 3-4 recovery breaths, your breathing slows down and gets back to normal (longer and a bit deeper exhales, etc.)

So, in short: to be able to inhale when having really full lungs, you do have to exhale first (no matter how little that is).

Hope this helps. (And if I'm wrong, someone, do correct me!)

 

[Danny.c]

...I'm not a spearo and I'm a lousy breathholder, but I do know that in order to be able to inhale when you surface, you must first exhale, no matter how little that is. You can exhale before reaching the surface. Exhale in the last 2-3 m before your mouth gets above the surface. Only then you will be able to inhale directly at the surface.
Another possibility is that you might have misunderstood or that the answers you got were not clear. In my AIDA 2* course, I learned this: when you surface (, cwt): exhale but do not empty your lungs entirely: make it a very fast, but shallow and passive exhale and then inhale rather fast, actively and deep and hold that breath for 1-3 seconds while "trying to breathe out" against your closed mouth. Repeat this 2-3 times. This is called recovery breathing. So, the focus is on the inhale being active and deep and not on the exhale which is shallow and passive. After the 3-4 recovery breaths, your breathing slows down and gets back to normal (longer and a bit deeper exhales, etc.)

So, in short: to be able to inhale when having really full lungs, you do have to exhale first (no matter how little that is).

Hope this helps. (And if I'm wrong, someone, do correct me!)

Ok that makes perfect sense to me.I had heard some were it was dangerous to exhale below surface so I was not sure what procedure was the correct one.But I make sense of what you say,more or less I need to start making room for some quick air on the surface then pump my self full of clean air then back to relaxing.
My current procedure just to relax then do 4 sec inhale 8 sec exhale with lips tight,for 5 min.
Then 80% inhale for the dive,but I have been holding that breath then exploding the water with a huge exhale.
Dose not sound too good when I think about it,but then again I am not pushing any limits.
Thanks very much for the great reply.I will give it a shot when My blisters heel ).

 

[Peter123]

Exhale twice as long for 5 minutes is on my opinion heavy hyperventilation! Also diving always alone is extremely risky. Just one shallow water blackout will lead probably in death....

 

[Mr. X]

Not necessarily (but I see your point), it depends on how you do it. Inhaling normally and exhaling slowly is often used as a calming/relaxing technique in yoga & meditation. For example, one well known meditation technique is to visualize the effect your exhaled breath has on the flame of an imaginary candle some way in front of you, typically trying not to disturb the flame.

Although just breathing fairly deeply and fairly slowly seems to work pretty well for me.

 

[Danny.c]

Not necessarily (but I see your point), it depends on how you do it. Inhaling normally and exhaling slowly is often used as a calming/relaxing technique in yoga & meditation. For example, one well known meditation technique is to visualize the effect your exhaled breath has on the flame of an imaginary candle some way in front of you, typically trying not to disturb the flame.

Although just breathing fairly deeply and fairly slowly seems to work pretty well for me.

Exhale twice as long for 5 minutes is on my opinion heavy hyperventilation! Also diving always alone is extremely risky. Just one shallow water blackout will lead probably in death....

Yes he might have a point but these breaths I take are very calming and exhale is slowed down from my valve like mouth ).And it is very calming and I do it like it is meditation ,I have known blokes who hyperventilate and I am not doing that at all.I am filling my blood(lungs) full of air then slowly releasing said air.
As for Diving alone,Yes very dangerous I know the risk and I choose to put my life in this situation knowing very well the dangers.
Reasons I dive alone-
1. I am sick of showing other divers my secret lobtser holes then have them show all there mates.
2. I have dived alone mostly since I was 16 and I am now 37 and enjoy the peace.
3.Sometimes I will dive 4 times in one week and the divers I know have not got the time to come along(hard to arrange dive buddys around here)
.And if I dive alone I can take my time and relax with out added pressure from other divers who want to push limits.(I like to take my time when diving,no rush)other divers get impatient with me.
4. Even if I did take one of my dive buddys ,it would not make much of a difference because we dive (selfishly)100m apart or more so even if I do black out there is no buddy system anyway,we just don't do things like that here.
5.I have never been close to blackout and I never ever in anyway push any limits in the ocean,I do that at home in the pool with supervision.(man has to know his limits)CE
To any guys new to diving please get your self a buddy.
After Jo Duikers reply I have decided to take a free diving course in a couple months because it just sounds very interesting,awesome and it will help in keeping me kicking.
Thanks for the reply Gentleman.

 

[Danny.c]

If anyone else would like to talk about the way they exhale upon accent and surface I would love to here it.
Cheers Dan.

 

[NoFair]

I exhale a bit and then do a fast breath in and hold for a few seconds after surfacing if I've been down for long.

 

[cdavis]

Breathing technique discussion: good way to start a freediver fight, lots of opinions. Rough idea of the science: any breathing rate above what you do unconsiously is hyperventilation. A little is unlikely to hurt you, a lot can do you in. Important point, its very hard to tell how much is too much, so less is almost always better. There is crude way to compare. Relax, sitting down, don't try to control you breathing, but monitor it. How many breaths a minute? Then experiment to see how much air is exchanged each time. It will be something like 1/10th of a full breath, 10 times a minute. Then compare that volume to what you are doing for a breathup. If its much more, and for most divers its a LOT more, thats enough to get you in trouble.

More science. Big breaths on surfacing, especially big exhales, tends to reduce cerebral blood pressure. If you are close to BO, that can push you over the edge. Its a good idea to take less than full breaths on surfacing and do hook breaths for the first breaths. Both help keep blood pressure up. Otherwise, I don't think it matters.

I prefer to begin exhaling just below the surface so that I'm ready for a breath the instant my head clears the surface. Less than full breath, three hook breaths, then full and fast breathing till I recover (a minute or less), then totally relaxed minimal breathing(I try not to think about it till the last minute). In the last minute, my breathing gets so relaxed and minimal that its almost imperceptable, then a couple of purge breaths and go. I dive half lung, so a full lung diver will be a bit different. For me, the above pattern produces longer and more comfortable dives than if I'm over breathing.

 

[Danny.c]

Ok , last thing I want is arguments between turtles.I thought free diving had become a complete and finished science,I did not realize it was a debated and not x-act science.(I am new to this style of diving ,had always been a cowboy diver in the past).
Yesterday I changed some habits and tried releasing half my breath on assent to hook breath(deep breath in, shallow out at pace about 4 times) then just return to normal breathing.

Wow. Yesterday was the best dive I have ever had in my life,I felt so much better and relaxed .Just these couple changes have made a huge difference.I feel like I can recover in half the time it usually would take me,And I scored 3 painted cray's to top it off.
Free diving can be the most amazing feeling.Its getting better and better the more I study the art and my own ability's.

 

[Danny.c]

. I dive half lung, so a full lung diver will be a bit different.
I will try this as well next time I am out,that might even be better for relaxing the stomach muscles etc...

 

[cdavis]

Glad to see you making such good progress

Interesting perception re a "complete and finished science" It definitely ain't that, which is what makes it so fascinating. We are all still learning. Its quite possible to discover new stuff, that nobody else has stubbled onto, that can have a big effect on your diving.

Have a care with surface interval. No matter what you feel like, there is no substitute for time. Half lung diving leads to the perception of very fast recovery. I can feel ready to go in a couple of minutes, but that doesn't work. I need 3-5 minutes for the times and depths I'm diving. Deeper means more time.

Explore half lung, aka FRC, diving carefully, with a buddy. A superior way to dive, but it feels totally different from full lung and can lead you into trouble. Read the thread on "Exhale diving for the "average" diver" That might not be the exact title, but you should be able to find it with a search.

 

[Danny.c]

Thanks,interesting stuff.I had a quick read.I will look into it with more detail tonight.
When you are taking your breath before dive down ,do you inhale full lung,then exhale half and dive,or is it best to just breath in half lung and dive?
So I am not at all an expert but it seems that its a'lot better to dive down in a semi static state and not having to fight a full lung of air but the trade of is less oxygen in the blood,
There seems to be a compromise between the two ,If you get what I am saying.
I will be testing this in 12ft as soon a I can .
You just opened up the rabbit hole for me.
cheers mate.

 

[cdavis]

If you stay interested in exhale diving, heres a link to theory and practice:

https://forums.deeperblue.com/threads/exhale-diving-theory-and-practice-a-laymans-view.103195/

I tried both exhaling to half and inhaling to half. Finally decided that it is more consistent to inhale half way then dive.

It is a trade off, and the strength of your dive reflex has a lot to do with what works best. Divers with very weak DRs, should not do nearly as well with exhale diving.

 

[Matthew Elkins]

I was tought to Exhale 5 meters below the surface during my ascent the reasons being A: I would be able to take my breath when I got to the surface to start to get oxygen back in my blood streaming and back to my brain
B: as I make my descent the volume in my lungs decreases and takes pressure off of my heart causing it to enlarge and pump and work differently and obviously on my ascent opposite happens and I want to let a little bit of air out so not to put that pressure on my larger heart from my lungs returning to the original volume especially in the last 15 feet where the most pressure change occurs there's a lot of technical terms to describe this but that's the basic gist of it.
Another thing I was taught to do to prevent a blackout on the surface is: upon surfacing stay really low in the water as you do your recovery breathing because if you come up out of water really high the loss of hydrostatic pressure can slow the circulation of or even pull some of the the freshly oxygenated blood down and away from the brain if you watch some of the videos of people blacking out a lot of them rocket out of the water then go into LMC or blackout anyways I know this is a lot but I hope it helped and if you can get a buddy

 

[Danny.c]

Thanks for the tips,Will keep this in mind,there really is a lot to remember when free diving,I am really looking forward to the apnea classes,I will try to get a buddy,what worry's me more than getting a buddy is.A few friends want to come diving with me lately,I am very hesitant to take mate's diving as they have no idea about the SWB risk and I do not trust them.I am hoping that once I complete some apnea lessons I may meet new people to dive with.

 

[jaritter]

I was tought to Exhale 5 meters below the surface during my ascent the reasons being A: I would be able to take my breath when I got to the surface to start to get oxygen back in my blood streaming and back to my brain
B: as I make my descent the volume in my lungs decreases and takes pressure off of my heart causing it to enlarge and pump and work differently and obviously on my ascent opposite happens and I want to let a little bit of air out so not to put that pressure on my larger heart from my lungs returning to the original volume especially in the last 15 feet where the most pressure change occurs there's a lot of technical terms to describe this but that's the basic gist of it.
Another thing I was taught to do to prevent a blackout on the surface is: upon surfacing stay really low in the water as you do your recovery breathing because if you come up out of water really high the loss of hydrostatic pressure can slow the circulation of or even pull some of the the freshly oxygenated blood down and away from the brain if you watch some of the videos of people blacking out a lot of them rocket out of the water then go into LMC or blackout anyways I know this is a lot but I hope it helped and if you can get a buddy

cdavis has made some good points and jo_duiker has a good explanation of hook breathing that's an important skill

There are some semantics here that I might be able to provide information on having just finished the AIDA 3 star course (literally today). This isn't definitive but it does qualify as "by the book" so take it as you will.

A: Exhaling below the surface can be a double edged sword. It allows you to breathe sooner and can "take some pressure off" of your lungs if there is still significant blood shift (See B), but it also lowers the partial pressure of O2 in your lungs putting you closer to a hypoxic state while underwater. At best I could recommend letting off a little air to compensate for blood shift. A full exhale at the end of a long hard dive is asking for trouble in theory. As a side note, the OP stated that he was diving at 80% lung capacity so shouldn't have any issue with too much pressure on resurfacing so there is no need to risk it.

B: This one is purely in the details because you have the right idea. The clarification is that the heart itself does not enlarge (this is a good thing as medically an enlarged heart is linked to quite a few health problems) but the lungs. Specifically the venous/arterial tissue (not the the air sacs themselves but the tissue around them). This is due to what is called blood shift in which blood moves more centrally from the extremities and acts as a buffer for the pressure on the lungs (see: mammalian dive reflex and blood shift). The end result is that the pressure in the chest cavity in theory can be higher returning from a dive than initially going down (because of reduced volume due to extra blood taking up room). This should really only remotely be an issue when you're at max inhale plus packing and doing long dives that are consuming a lot of O2.

Not trying to nitpick Matthew, but thought I could clarify.

I agree with taking a course (the second tier course really upped the physiology and why we do what we do) and getting a dive partner.

Until then have fun and dive safe!