Headache

[Trulle]

Hello. I´ve got a problem when holding my breath under water for a longer time. After a while i get a irritating and painful headache, like a sort of cramp. I´ve heard that it is a sign of low Co2 tolerance. The pain lasts only for a few minutes. Does anyone know anything about this?! Is it dangerous? Possible to get rid of?

Would really appreciate some answers! Thank´s.

Trulle

[naiad]

Does it happen at depth or when you are holding your breath near the surface? If it only happens at depth it might be sinus squeeze. If it happens during any apnea it may be CO2.

Lucia

[trux]

As Lucia wrote, if it is depth bind, then it is likely compensation problem. As for CO2 tolerance induced pain - I'd tell that more likely would be headache due to high blood pressure. Body reacts to apnea with so-called mammalian diving reflex, whose main purpose is sufficient supply of critical organs with blood and oxygen while in deep saving mode. That's achieved by reducing the circulation in extremities and incritical organs, and increasing the blood pressure through vasoconstriction of most but the needed blood vessels. Diaphragmatic contractions will further increase the blood pressure in brain.

Persons sensitive to high blood pressure may indeed suffer from intensive pain. Persons susceptible to brain strokes should probably avoid doing apnea. I do not suggest that it is your case, quite possibly there is no problem at all, but I think that it would be very wise to visit a doctor and have a good medical check. Best would be probably a neurologist or brain specialist with a tomograph who could scan your brain (possibly in apnea) for susceptible veins. If would be much better if the doctor had some experience with freediving (could be also sleeping apnea - there are similarities with freediving), otherwise he may not be aware of all the effects of prolonged apnea and strong diving reflex.

[Fondueset]

I once had a headache that lasted two days after doing a bunch of dives to about 8 meters with very short intervals. It was not an abrupt acute headache though - it felt more like the kind of toxic headache you get when you quit drinking coffee for example. I assumed it was CO2 and/or other exertion related toxins since the dives were stupidly frequent. I was also overheated in my 5 mil suit - water temp was 73F.

[trux]

Yes, prolonged exposure to high CO2 levels can indeed cause headaches, dizziness, and other problems due to the toxicity of CO2. Some describe the pain being similar to hangover. However, it does not look to be the case described by Trulle - well, maybe at sensitive persons, already very short exposure to relatively low CO2 level can cause problems, but as I wrote I suspect that it may be related to the high blood pressure. Qualified doctor should be able to find it out. You could also try invoking hypercapnia without apnea (by very shallow breathing or breathing through a paper bag) to see whether it is the CO2 alone, or rather the high pressure causing troubles - but it would be better doing it under medical supervision anyway.

Some articles about CO2 and headaches:
DAN Divers Alert Network : Headaches and Diving - UPDATED 2005
SpringerLink - Journal Article
Re: Nocturnal Headaches

[Fondueset]

I agree. I've never experienced anything really acute. I did once have a sinus let go upon surfacing - with an interesting sort of whistling sound - obviously got plugged up on the way up. But consistent, acute pain is definitely something to look into.

[Trulle]

Thanks for all answers!

I´ve got a normal blood pressure (100/60), and i don´t even have to be under water. The ache can appear even when bencpressing. I think that I might have sleeping apnea sometimes, due to my very loud snorings.

/Truls

[trullalla]

hi trulle,
to me it sounds like a co2 headache.
i get that a lot when i do CO2 tables during my swims. it comes much easier if i'm a bit dehydrated, so make sure you drink properly before you breath holding sessions. with proper training you will get more tolerant to high CO2 levels, and therefore get less headaches, or get them later on during your breath-hold.
i used to get that also when i was scubadiving, because i was so used to hold my breath uw while freediving. doing that you accumulate CO2 in your system and you get a headache first, followed by nausea. not a very nice feeling.

cheers
linda

[Trulle]

Thanks Linda, I´ll try that. Last week I red in a hurry about trying to reach your front chest with the chin. This exercise had a really odd name. Someone who knows what I mean?

Trulle