Does my heart skip beats or dive reflex?

[Svedberg]

Me and my friends who i practice with usually warm up with negative dives(95-99% exhale) too 3.70(pool depth) and last months ive started pressuring myself more and more in these, it gives a great feeling for the rest of the practice.

Anyway after about 6-10 seconds my heart rate drops more than half and feels "heavy" which kinda creeps me out just waiting for the next beat.
I have never had any noticeably dive reflex when doing dyn/sta etc and i have very limited experience of cwt so i cant say how my body reacts too pressure with full inhale.

Should i go and get it checked out or just learn to enjoy it?

 

[sanso]

You should already have gone and gotten checked, before You play around with things like that. But it's very possible that it's really the dive reflex kicking in nicely.
It will be more enjoyable once You've been checked and You know for sure that Your heart is okay.
Feel the beat.

 

[Svedberg]

Okay i will do that, what tests should they do? EKG and?

 

[BreatheDeep]

That's really the only thing I could think that they would do if you only have a suspicion that something is going on with your heart. Make sure though that when you do go in give the doctor the situation where it's occurring and not just what the symptoms are, you may not even need an EKG.

 

[K.Johansson]

We (me and svedberg) took our divers certificate the fall of 2008 where we had a "diver oriented" doctor do a check up, tho it only lasted for about one minute (he listened(?) to our heartrate etc). Still worth doing another "check up" since the "dive doc" gave us the ok and thumbs up ?

 

[colinox]

We (me and svedberg) took our divers certificate the fall of 2008 where we had a "diver oriented" doctor do a check up, tho it only lasted for about one minute (he listened(?) to our heartrate etc). Still worth doing another "check up" since the "dive doc" gave us the ok and thumbs up ?

That is a basic medical which looks for obvious signs that you are fit / unfit to dive. You feel this only happens when you dive, so a quick check-up would not observe this. I agree it may be Dive Reflex but it is always better to be safe and see a doctor.

The issue which really worries me is you guys 'warming-up' with full-exhale statics on the bottom of a 3.7metre deep pool! Are you suicidal?

 

[K.Johansson]

our warmup vary, but 99pct of the time we do dyn and just "freedive" around for 10-15 mins before we do actually do "laps", so the exhale dives comes after around 30 mins, i agree we could use a softer start on those, but 80pct exhale and the first tries are around 10 sec.

and no we are not suicidal, to put it out we know about nothing about freediving and we will stop doing that from now on.. do you have any facts or info about what or why this is bad and in wich way (im not saying i dont belive you, i just want to learn more about diving/freediving).

 

[colinox]

our warmup vary, but 99pct of the time we do dyn and just "freedive" around for 10-15 mins before we do actually do "laps", so the exhale dives comes after around 30 mins, i agree we could use a softer start on those, but 80pct exhale and the first tries are around 10 sec.

and no we are not suicidal, to put it out we know about nothing about freediving and we will stop doing that from now on.. do you have any facts or info about what or why this is bad and in wich way (im not saying i dont belive you, i just want to learn more about diving/freediving).

I have a lot to learn too. The most important thing is to take a course with a qualified, experienced instructor (AIDA or similar). I'm half way through the AIDA** course, just waiting for warmer weather to do the open water part!

When you do full-exhale, things can go seriously wrong very fast and there is negative pressure in your lungs so much more likely to get water in lungs than if you had positive air pressure in lungs. For statics always do them at the surface and always have a buddy beside you so if you have a BlackOut / LMC (samba) he / she can immediately turn you over, hold your face above water, then BTT - Blow on the eyes (lets your body know it is in air now), gently Tap you, and calmly Talk to you, say your name and say "breathe" - that usually works, and call for professional medical help if that does not work. Do a search for BTT if you do not know it already and practise apnea with plenty of air in your lungs until you are more experienced. I have not yet done full-exhale in water because I have never had an experienced buddy to help in case of emergency. Main thing is to do a course because then you will learn the safe way to do apnea.

Sorry if I sounded offensive, I was just worried and wanted to make sure you practise safely. Happy diving.

 

[K.Johansson]

i dont take stuff to personal, im aware of language barriers and that people express themselfs in diffrent ways without trying to be hostile or rude, so that's not a problem.

from my knowledge with negative dives is that you reduce your lungvolume to it's residual (sp?)volume and it's about 1.5 liters, but if you do cwt or similar down to ~60m (im not sure the actual depth) you are going below that volume anyway.
and we always have one/two or more at the surface, and one freediver at the bottom with the person doing the negative dives. i'm sure there are 300 diffrent views on this, but are there any "hard facts" (i have yet to google about it and will do after ive posted this, so might edit it in).

and yes, we are planning some freediving courses this spring/summer/fall with sebastian so hopefully we will learn about everything we need (and lack).

thanks for your time, be safe.


edit: http://forums.deeperblue.com/freediving-science/80752-inhaling-negative-depth.html

 

[colinox]

i dont take stuff to personal, im aware of language barriers and that people express themselfs in diffrent ways without trying to be hostile or rude, so that's not a problem.

from my knowledge with negative dives is that you reduce your lungvolume to it's residual (sp?)volume and it's about 1.5 liters, but if you do cwt or similar down to ~60m (im not sure the actual depth) you are going below that volume anyway.
and we always have one/two or more at the surface, and one freediver at the bottom with the person doing the negative dives. i'm sure there are 300 diffrent views on this, but are there any "hard facts" (i have yet to google about it and will do after ive posted this, so might edit it in).

and yes, we are planning some freediving courses this spring/summer/fall with sebastian so hopefully we will learn about everything we need (and lack).

thanks for your time, be safe.


edit: http://forums.deeperblue.com/freediving-science/80752-inhaling-negative-depth.html

It is good to know you are planning courses - and I am glad you did not take offense.

The issue has nothing to do with lung volume at depth, it is a simple issue of safety. Any static apnea, whether it is with full lungs or empty lungs or partly filled lungs should be done at the surface in case of emergency. I have experienced a samba and blackout once and it happened when I did not expect it. When it happened my maximum static time was 5:01 and I could easily do 50metres dynamic without fins, but the samba (LMC) and blackout (BO) happened after only 10metres! I always thought there would be warning signs so I could abort the apnea, but in reality it was like being a passenger in a high speed car crash - it happened so fast there was absolutely nothing I could do to prevent it. If that happens to you at the bottom of the pool with empty lungs your buddies need to work hard to get you to the surface before they can help you recover, but if you are already at the surface they only need turn you over and can start helping you immediately.

If you have not researched the warning signs of a blackout or samba you need to do that, and you need to research and practise what to do in case of emergency. If you have practised what to do in case of BO / LMC and this happens to your buddy then you will not panic (Hopefully!), you will just do what you have practised and your buddy will recover within 1 minute. The method for helping a freediver recover from BO / LMC is called BTT (Blow, Tap, Talk) and it is very effective, although the victim usually just needs a few seconds with their face above water to naturally start breathing again. I do not have enough experience to explain much more so the best thing for you and your fiends to do is to research all these things, read many posts in the Beginner Freediver section (sorry I do not know how to make links), and do the course as soon as possible.

At great depth where you would expect the lungs to compress beyond RV, a natural human adaptation called Blood Shift happens. Blood vessels in the limbs and extremities contract due to the pressure and this pushes blood into the core of the body. Blood moves into the lungs to compensate for the compression of the air. This prevents the lungs compressing any more as the freediver goes deeper, and prevents lung collapse. We do not need to train to do this, it happens naturally. I wish I could tell you what it feels like but I have never dived deep enough to experience Blood Shift! Maybe one day....!

I hope this helps. Safe diving

 

[Svedberg]

Thanks for your answers

 

[K.Johansson]

As a matter of fact, we value safety very high so we practice it every time we go freediving. And we had our first LMC occur at our last practice wich i think we handled pretty well for beeing self taught.
but i got a bit shocked when you said you can get lmc/samba so early in a dive, i always assumed it had to take a certain time before you had to worry about it happening, and i dont mean it never happends before 1 minute or at a certain time. but doing 50 meters dyn i wouldnt expect it to happend the first 20-30 meters (and im not talking about someone doing it for the first time every).

thanks a lot for your answers, really opened my eyes about safety during dyn.

 

[cdavis]

Hi Svenburg,

I missed this thread at first. thanks for posting an interesting thread.

Couple of things.

You have almost certainly been experiencing some degree of dive reflex in your full lung diving practice, just not near as much as full exhale. Get a heart monitor, static for a minute or so and watch your heart rate fall, then start swimming and it won't climb very much even after a minute or so. Start breathing and watch the heart rate spike. Thats all a part of dive reflex.

Good advice above on getting checked. Try to get the doc to do any tests while you are doing a full exhale static in the office. That might well reveal something that a normal test would not. If you want to scare him to death, get him to do a fingertip 02 saturation test while you do a long exhale static. It will get low enough for him to think you are dead. Perfectly normal dive response.

Full exhale statics in the deep end of the pool have a dicey reputation. Quite a few people have reported early BOs doing that. I've not had that problem, but have proceeded slowly. Full, forced exhales plus a few reverse packs and I also get a very strong dive response. I've run that out to a minute and come up before significant contractions. So far, no signs of any problems, but again, proceed slowly. Its not the same thing as diving to depth below RV because you are carrying so much less 02 with you. You can also get squeezed doing this because the pressure change is so rapid. Not something you want to experience.

You guys might be interested in FRC diving. Use the search function for frc, exhale diving, half lung, etc.

Definitely, take a course. You are ready for it. It will open a whole new world of diving to you, no matter what your level.

Good luck and have fun.

Connor