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Apnea walks and CO2 blackouts?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Well-Known Member
Jan 21, 2004
I started Apnea walks yesterday and was having some serious head spins and loss of vision for the first 10-12 steps each time.

I was pushing them fairly hard (lots of contractions and to the beginning of fading vision (tunnel) with 3min recovery breath ups in between(slow and deep - 4per minute 2 purge breaths no packing). I haven't had a buzz with this type of breatheup for statics but when I stood up and started walking each time I was almost without vision and must have looked like a drunk stumbling home after closing at the local. It only lasted for about 10-15 secs each time but wasn't much fun.

Any explanations for this would be appreciated.


The way the explanation is simply that the pressure on your heart from the full lungs as well as the standing movement both inhibit blood flow to the brain, precipitating blackout symptoms.

From your post it sounds like you are starting the walk straight after your last breath. If you insert a short static (1 - 2 minutes) before getting to your feet then you shouldn't have any problems with fading vision etc. Also if you perform the exercise on FRC (normal breathe-up but finish with a casual exhale) then you will be a lot more comfortable while walking and you will be able to cut down that huge recovery interval of yours:) You could try:
1' FRC static
Walk as far as you can
1' recovery

Thanks and I'll add a short static to the beginning of each walk.......what's the benefit of reducing my HUGE :) recovery times?

.......sorry forgot to also ask why FRC/FRV for apnea walks....is it to reduce lung pressure on the heart?


Reducing recovery intervals will mean you spend a greater proportion of your session in the 'hypoxic zone' (ie you will be able to do more repetitions in a period of time). Basically greater training stimulus = faster improvement.

The benefits of FRC as opposed to TLC in apnea walking are:
- Shorter interval to hypoxia (faster training)
- Shorter recovery
- Greater comfort: contractions are less of an ordeal and you don't feel like you're going to burst all the time.
- Finishing the apnea with an inhale is a lot more natural.

A good training principle is that unless you are going for a maximum attempt there is no point ever inhaling. Blood quality, hypoxic and hypercapnic resistance will all be trained more efficiently on FRC. Eric Fattah is a main proponent of this theory - search his posts for good explanations.
  • Like
Reactions: Fred S.

Just tried the FRC approach to apnea walking. It feels like I am getting much farther into low o2 condition, rather than fighting with co2 levels. Good tip, thanks


Internet and deeperblue: two guys with similar questions on opposite sides of the world, answered by a third guy about half way between and none of them know each other. AMAZING
Will & Connor,

I tried FRC for a static session and was amazed at how relaxing it became. With the FRC approach I was feeling very hypoxic but also very relaxed/not stressed about it. Contractions arrived but were less like a suffering and more of something to observe. I'm looking forward to trying it for walking.


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Good to see it's working for you guys too. Just a note to watch out for the hypoxia - unlilke TLC apnea walks (which are CO2 limited) you won't get hypercapnic signals before blackout. Therefore it's best to practice on a beach or soft grass. After a while you will get good at judging the onset of a BO and be able to push yourself right to the edge then sit down while you control a samba.
Always amusing for onlookers...
A beginer

Sorry if it seems as old information but I'm a new comer here and wanted to know what is FRC diving, TLC diving and what is the apnea walks good for?
last week i was sitting infront of the computer and decided to make few breath hold to put to good use the time. I inhale deeply and decided to make walk in the room. When i stand up i feel fuzzy like drunk too much beer but i think its normal since it sometimes happens in the beginning of the breathhold and i packed 5-6 times, after second step my vision went and fell on the radiator (big metal one) and hit my elbow to the desk... It was really bad fell freaked me much never try that again, luckly i did not hit my head, well i guess i did not couldn't find any deformation:eek:
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I have never been able to push my apnea walks to samba or bo, but with the FRC approach, it looks much more likely. Thanks for the warning. I'll be doing some more tonight.

Just tried a series of FRC walks, tricky not to fall down, but the technique really lets me work on low o2, not so much co2 tolerance. I've been looking for a technique that would do that.

Then I tried a full lung walk. Blew right past my pb (set when I was much better trained) and kept going, only stopped because it seemed like a good idea. It was almost 25 % farther than yesterday.

Very impressed with FRC, Thanks Will.
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