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Co2 - o2 tables training

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
Just did my first CO2 tables (using the iHoldBreath iPhone app). Table looks like this:

Ventilate 2:25
Apnea 2:30
Ventilate 2:15
Apnea 2:30
Ventilate 2:05
Apnea 2:30
Ventilate 1:55
Apnea 2:30
Ventilate 1:45
Apnea 2:30
Ventilate 1:35
Apnea 2:30
Ventilate 1:25
Apnea 2:30
Ventilate 1:15
Apnea 2:30

The times are set according to my PB (5 mins). I did not find this table challenging at all. I did not get a single breathing reflex, I did not feel I had to put any effort in.

Now, are the tables supposed to "challenge" you? In any other form of training I've been involved, intervals are used for pushing limits. Should I fake a better PB in the settings of the app in order to push my limits? Or does CO2 tables training follow a different logic than the training I'm used to (which would make sense, I'm usually into aerobic training, e.g. running or cycling).
 
Such long recovery times are useless at a CO2 table. Cut them all by one minute and breathe normally during them (no deep breathing)
 
OK, that makes sense. I guess the point would be not to vent out all of the accumulated co2?

I've read at some places that one should not do this type of exercise more than once per day. Now, I won't (I'll go for twice per week: one CO2 and one O2), but I wonder what dangers are involved?

Instead of following the original tables of the app, I'll go for this (for CO2):


Calm down 2:00
Apnea 2:30
Ventilate 1:30
Apnea 2:30
Ventilate 1:20
Apnea 2:30
Ventilate 1:10
Apnea 2:30
Ventilate 1:00
Apnea 2:30
Ventilate 0:50
Apnea 2:30
Ventilate 0:40
Apnea 2:30
Ventilate 0:30
Apnea 2:30
 
Sorry for repeating myself, but how far can one push the inbetween times? Potentially 0 of course, but... The above table did never got me into contractions.

Why I'm asking is, again, if there are any dangers involved. Is there e.g. an increased BO risk in the exercise?
 
As I wrote earlier, you best cut the times by a minute, that would result in a 15 s last recovery - you should repeat that last cyclus 2-3 times. You can go down to a single exhale/inhale. The risk of a BO is relatively low at high CO2 levels. There is a certain risk of CO2 blackout at extreme levels, which is then difficult to recover, but it is unlikely you'd suffer it if you do not even feel any discomfort. You can increase the breath-hold times, if it is still not challanging.

However, you should not train alone anyway, it is always better having someone close, even if you do a dry training. At a pool training it is a necessity in any case.
 
OK, thx for this trux! I do indeed dry-train alone (only time when the home is calm) but I'd never do that in water of course. I guess I'll reconsider my strategy when I feel closer to limits.

It is certainly interesting to see how the body reacts, anyway, only I've only done this two times so far...
 
Hi again, thanks for the advice given. I've continued working on my CO2:s and about a month ago I switched to FRC hold (following the advice of my dive buddy):

Ventilate: 60 s
FRC hold: 90 s
Ventilate: 60 s
FRC hold: 90 s
Ventilate: 30 s
FRC hold: 90 s
Ventilate: 30 s
FRC hold: 90 s
Ventilate: 15 s
FRC hold: 90 s

I repeat this sequence six times. The first repeat is the hardest, the final two are quite comfy, I feel I'm in "the zone" and just enjoying that completely relaxed feeling of an FRC (that is quite impossible to explain to non-apneaists )

However, any suggestions on how to push on? As I see it there are three options:

1. Increase hold time
2. Decrease ventilation time
3. Go for less than FRC (e.g. full exhale)

Option 1 seems less attractive as it becomes even harder to fit it into the training schedule... Any ideas here, esp. re option 2 and 3?

//nen (aka @jalvehus on twitter)
 
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What's the rationale to switching to FRC our of curiosity Nen?

I'm by no means an expert and don't do tables but I don't think it makes much sense to switch to FRC holds if you are doing CO2 tables because the whole point is to build up CO2 so you need your holds to be longer...

I would personally not go down the route of doing a full exhale - you'll just make the holds even shorter which means that you'll have even less CO2, which makes no sense to me. Instead of that, just increase the hold time on full inhale.

Also your times look a bit odd - why don't you keep decreasing the breathing time? you could do 60, 45, 30, 15 but instead you seem to be doing 60, 60, 30, 30, 15?

If you were doing an O2 table then maybe it would make more sense to go to FRC or empty lung so that you keep the holds shorter than they would have to be on full inhale and thus save some time.
 
Also, do you really do this 5 hold table 'SIX TIMES'? That would take over an hour right?
 
Would it be of advantage if you held your breath for a couple of times after short ventilation.
eg.

Vent. - Apnea
1:00 - 1:30
1:00 - 1:30
0:45 - 1:30
0:30 - 1:30
0:15 - 1:30
0:15 - 1:30
0:15 - 1:30
0:15 - 1:30
0:15 - 1:30

?
 
@Simos: I'm pretty new to this (2,5 months, actually) and I'm basically trying out different techniques to see how I react. FRC made sense in that it gets me into contractions earlier. This routine with full lungs would easily take at least 1 extra hour... But if I'm on the wrong track I'll happily take any advice!

@Siku: Yep that's right, 1 hour 5 minutes. Quite a nice break during the day

@Shark: Something like that was in my mind. On FRC then.
 
Wow! You're CO2 tolerance is going to go up with that sort of work out.

@Simos: Surely FRC holds result in CO2 buildup earlier - less air in the lungs to dilute the CO2 the air the body produces?
 
Siku said:
Wow! You're CO2 tolerance is going to go up with that sort of work out.

@Simos: Surely FRC holds result in CO2 buildup earlier - less air in the lungs to dilute the CO2 the air the body produces?
Click to expand...

What matters is the CO2 levels in the bloodstream... CO2 level in the air in the lungs is irrelevant as far as i know. The more O2 you have available for your hold, the bigger the amount of CO2 that will accumulate in the bloodstream.

This is why hyperventilation lowers the urge to breathe - say you hyperventilate for 2 mins and then you take a fresh breath of air and hold, the air in your lungs has the normal % of CO2 but not your bloodstream.

Obviously I stand to be corrected
 
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By the way if CO2 level in the air in the lungs was what mattered, the CO2 tables would not work in the first place since even 1 breath of ventilation would mean that you'd get rid of all the CO2 and 'start again'.
 
Reactions: jay cluskey
I also thought what matters is the CO2 in the blood. But I assumed that the PP of CO2 in the lungs would determine the amount of CO2 that is cleared out of the blood as it pass the alveoli. On an FRC hold the total lung volume is lower, so a given amount of CO2 created will cause a higher PP CO2 than the same amount in a larger lung volume.

Otherwise why are FRC holds harder (assuming my current tolerance to low CO2 doesn't allow me to experience low O2 urge to breathe).

BTW, re HV: I understood that the increased ventilation rate led to lower average PP of CO2, hence lower CO2 in the blood.

Where's Trux when you need him?! ;-)
 
Well, both is more or less correct. The CO2 in lungs raises first quickly untill it reaches certain level, and then only slower, while building up in the blood. Hence lower lung volume will lead to a slightly quicker hypercapnia, but because a hold with emptier lungs usually means shorter time, the time spent in hypercapnia will be (typically) shorter. However, it all depends also on other factors - especially the breath-up, and the consumption during the breath-hold - the DR may be quicker under FRC, hence the O2 consumption and CO2 build-up slower.
 
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So which trains CO2 tolerance better - a short time very hypercapnic, or a longer hold time but less hyper capnic?
 
Siku said:
So which trains CO2 tolerance better - a short time very hypercapnic, or a longer hold time but less hyper capnic?
Click to expand...

Can't type too much right now but I really doubt FRC will be more hypercapnic.

With full-lung will you will/can spend more time at higher CO2 levels than FRC.

Besides, assuming you are diving full-lung, you are better off getting used to full-lung, longer holds.
 
Each exercise has its pros and cons. With each you train slightly different aspects, so it is good to alternate. You can also do a long series of short breath-holds with just a single breath in between them - in such way you'll be pretty hypercapnic for a long time without having to go deep into hypoxia. And in such case it matters little whether it is FRC or full lung. Though with FRC in such a series you reduce the comfort time considerably, so you spend most of the time in a struggle phase.
 
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It might be a very special question that occured to me, but trux do you know by chance how quickly the body starts his metabolical answer to hypercapnia?
In other words:
Hypercapnia lowers the pH of the blood, acidosis builds up.
As the body regulates the pH of the blood within a small range, does the metabolic compensation start faster in freedivers?
keyword immersion diuresis?
 
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