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Physiological versus mental CO2 tolerance

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
Would the following be fair as a “rule of thumb”?

1. Physiological CO2 tolerance can be determined by the point at which contractions start (all other things being equal - ie 4mins before contractions start is better than 2mins)

2. Mental CO2 tolerance can be determined by the number of contractions sustained. (ie 60 contractions is better than 10)

….or maybe I’m missing something important here?

If the above is reasonable should we be training the 2 aspects of CO2 tolerance separately and perhaps focusing on one more than the other depending on which is the more limiting factor?

Hi folks.....60 views on this and no comments yet....any ideas on this one?
I think you're generally on the mark. But, I also think that mental tolerance may never be lost, much like riding a bike. If my life depended upon it, I could probably hold contractions until I blacked out, even with no physiological CO2 tolerance. Even without mental training---only because I have done it before.

Eric Fattah
BC, Canada
Hi Eric,

Thanks for the comments. Do you think it's possible to improve one and not the other....perhaps even go backwards? In looking at my training diary for the past 18months it seems that contractions are coming earlier but I'm putting up with a whole lot more of them and I'm wondering if the mental tolerance is improving but the physiological tolerance is going south. Overall times are much the same. Prep, time of day, hydration etc is recorded in detail and as close as possible is replicated.


In fact, has anybody gone backwards in static times? It seems like a mental game (once past the contractions start time) .. once you pass the 4 min mark once, you pass it always, 5 min and again.. and so on. Or at least for me is like that :D
Maybe I'm building towards a time ceiling and once there, it's a more multi-variable 'esoteric' personal thing. It seems like that for most people :)
I have, kind of...

I have done 6:30 (talking about dry statics here, pool season just starting), but on most days I'll struggle to make 5:30. In fact I have passed 6 only on 2 occasions.

These days I train for 2 times. I try to increase the time that I can reach every time (at 5:30 now) and then if everything goes well, there's the "absolute personal best" (at 6:30). The "every time" mark I'll try to grow subtly with each try, say 5 sec. The latter I'll try to break in leaps, or what ever feels good. Since passing 5 minutes, I don't think I've made a pb leap less than 20 sec...Hoping to keep that up ;)

As for mental vs. physiological, I feel that right now, I'm in better physiological shape. I could hold my breath longer on most try's, but I just get this sort of "why bother, this is pointless" feeling. I'm hoping to get new motivation from moving to wet statics again. I could do almost 60 contractions before, but now I'll struggle at 20-30. We'll see...
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I've gone backwards in statics, too. I think it has / had a lot to do with conditioning (Pawlow and all the other guys...). When playing around with patterns for my statics I tried not to focus on time but counting the contractions and coming up after a certain number of them. The effect was that I started to get the contractions earlier every training session and my static times shortened significantly. When I stopped this practise I went back to my "usual" static times after a few sessions.
So, no counting of contractions for me :t ...
The biggest point certainly is motivation and - at least for me - if you are in a good or a bad mood.

Just a thought.

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I usually start getting contractions in the first
warm-up hold around 2 minutes. So If I think.. 'I'm going to delay the contractions' or better 'This time my contractions are going to come at 2:15 secs' that's what happens exactly at 2:15.
But If I'm not motivated... then... when I look at the clock and I see 2:00 minutes the I feel at that moment the first contraction :D
So, for me It seems too that if you think 'Ok, I feel like 4 minutes today' you'll do it. I think the whole point is to just forget you are holding your breath. Not an easy thing :p
Originally posted by BlueIcarus
I think the whole point is to just forget you are holding your breath.
That is what I try to do. When I first started training my thoughts during a static were in the easy part "Hey, I'm holding my breath!" and during the difficult part "Help, I need to breath, will I pass out, how much more of this can I take?" This obviously didn't help. Now, even when it gets really difficult, I often find myself relaxing completely or thinking of something else. This is something I have to work on, because I'm sure that it would be possible to gain more time by being more relaxed from the start.

I'm sure that my physiological CO2 tolerance has increased with training, but this has also made it difficult for me to know my limits. It's mostly a good thing though!

Jacques Mayol realized this when he had an error clocking himself, thinking that he was already 2 minutes in the water when in fact 4 minutes had passed. Anyways, I wouldn't put my hand on fire for anything Mayol did/said :D.Altough it makes sense b/c on my longest statics I always think that the time the clock says that had passed, haven't passed yet hehe
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Originally posted by BlueIcarus
Jacques Mayol realized this when he had an error clocking himself, thinking that he was already 2 minutes in the water when in fact 4 minutes had passed.
That can happen - in my first training session, about a year ago, I told my buddy to tap me at 1:00 then every 15 seconds, but he thought I said 1:00 then every 30 seconds. I did what I thought was 1:30, but was in fact 2:01, which was a PB at the time! Maybe I need a bit more of this. ;)
How about manufacturing the 'Apneist Crazy Watch', which is a watch than can randomly vary one second (one fixed for each hold) length from 1s to anywhere between 0.5 secs and 1.5 secs, so you have
a full -50/+50 % uncertainty over your actual hold time :D . Also It's a good device for arriving at work on time... just introduce a random variation in the minutes each morning from -10/+10 minutes. So you always hace to arrive 10 minutes before (in the changed clock) your actual time just in case the clock is -10 minutes. But you can actually arrive 20 minutes before if it's at the + 10 minutes setting. Ok, so you'll end up looking at other people watch or asking :D
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Great idea for statics, but who wants to arrive at work 20 minutes early? Sitting around with only a computer and water cooler for company... :D
"or maybe I’m missing something important here?"

"If the above is reasonable should we be training the 2 aspects of CO2 tolerance separately and perhaps focusing on one more than the other depending on which is the more limiting factor?"

Maybe the third option is closest Andy. Tables are best used for maintenance. It is better to focus on the goal. If numbers on a stopwatch is the goal, you can develop a technique to hold to max, blackout, wake up and then stop the watch. Great times, bad idea and possibly fatal in the pool.

If you expect contractions at two minutes, that's when you get them. If you 'know' you can do a six minute static, you can. When it starts to hurt, the mind has doubts, is more active and O2 consumption rises. The physical and mental are tied together. IQ gets in the way. The closer you can get to turning the mind off the better. This can cause a big problem on constant ballast though. Try to learn to enjoy the contractions or to accept them as a sign of success.

When you feel your performance slipping, listen to your body and take a few days off, especially now, in the winter. In season it may be better to cut way back for a while or go to the pool and goof off for a trraining session or two. Try to seperate the mind from the body again.

If all else fails, let me suggest a week or two at Pu'uhonua O'Honaunau, where the women lie on the lava with hardly any clothes on and the divers tolerate a gimpy old man in his long quest to 'dive his age'.

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I always found in statics when I was in static form that contractions would always come at the same times, but what seperated a good session from a crap session was the length of time I could hold them for. On a crap day I could only hold them for around 1:30 on a good day that would go up to around 2:15.

However that been said I have had such a difficult time keeping any consistency with statics that I have given up on them. I dont understand why at the start of the year in feburary I had a static pb of 6:45 then from there things just went down hill to the point where a good day would be 5:30. There was no change in my fitness or whatever I kept everything the same. I havent done any statics for quite some time and dont expect to in the near future due to the frustrating inconsistency in this sport.

I think there was a thread about "static burnout" before. Basically what happens to most people is, that after a whopping start and incredible results in the beginning, we lose motivation once it gets "hard" to significantly improve or even maintain the results. I think it is therefore healthy to have longish breaks from hard static training once in a while. The fact is, it just gets really boring really fast.

I've made huge leaps in my dry statics this summer. In fact I jumped in my pb in of 4:07 to 6:30 in less than a month. I hadn't been really training statics for almost half a year. But now I can't seem to improve on that or even maintain that level, and I think it is just simply the "why bother"-feeling that I described before. After such leaps, it feels pointless to get another 1 or 2 sec and just damn frustrating to fall short of your previous record. That's why I swithced the target from "absolute pb" to the "guaranteed result". And as I said, I'm hoping to get new motivation from moving to wet statics again...
I think the "guaranteed result" way of training is good. That is the way I train now, and it seems to have good results.
Hehe It seems like we all have gone through the same proccess here (trial and error!!)
I train also at the "guaranteed result". And
the "result" is that I could go to training mark
easier each time, and suddenly one day I realize moving onto the next mark is... plain easy, and the I move.
For me, this type of training is way more
rewarding psychologically, because I leave
the training with two good tastes:

a) Apnea is easy and relaxing :D
b) I'm moving towards another goal

Also, I think the PB costant fight leads to overtraining... I prefer to keep it easy!!

I wonder, did improvements in static breath holds have lead to improvements in dynamic or C/W ?
Hi Bill,

Thanks, whereas before I'd just got bummed about crap static I'll now take solace in that it might indicate a higher intellect, glass is half full after all!!

The “link” is interesting food for thought and creates an issue for my usual approach of trying to break things down and simplify things…..oops maybe the higher intellect remark isn’t warranted after all!

I’m about 75% likely of a visit mid October and will let you know.

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