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Question Individual CO2 Training?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Feb 26, 2021
Hi there,

what I get from reading is that high CO2 feels different for everyone. I am a beginner and struggle a lot with high CO2. My static dry best is 3:30 but even when doing CO2 tables even 1:30 holds are unpleasant. Sure I get contractions, but what is the worst is the feeling of energy running down my spine and into my arms, legs and lower belly, intestines. It is like impossible to stay calm and I feel the constant need to twitch (producing even more CO2). I believe that a more experienced person would just go into relaxation but for me at this stage in the hold its impossible to simply ignore these sensations. Especially when I am in my bed and not moving at all, I cannot draw my attention to something else. I wonder whether other people experience similar sensations and whether they have found specific approaches dealing with them. Could it be beneficial to switch to something like CO2 walks instead for me? Since pools are closed here all my options are dry at the moment.

Thanks a lot for ideas.
Just my suggestion, for starting out try not to focus on duration/intensity, it is important to develop comfort and relaxation. Try doing a higher quantity of shorter breath holds through the day. Repetitive holds up to the first couple contractions will help delay them for when you work up to longer holds. Once you get to no contractions until two minutes practice longer holds. This will make it easier to not lose motivation starting out, many divers don't even bother with statics and just do walks/exercises.
To expand on the response from 7BDiver, it may take up to 20 minutes, or even longer, to get comfortable. So do short holds until you feel more relaxed. Then start to push further.
To expand on the response from 7BDiver, it may take up to 20 minutes, or even longer, to get comfortable. So do short holds until you feel more relaxed. Then start to push further.
@hteas can you expand on or explain what you mean by "it may take up to 20 minutes, or even longer, to get comfortable". I am interested to know what is causing that ?
It takes time for the spleen to release the red blood cells it holds. It also takes time for your body to minimize blood flow to the arms and legs, saving the oxygen for the core and brain. It also takes time for your heart rate to start dropping. In a trained diver it takes little time for these changes to occur. In untrained divers it takes time for these to occur. I'm sure there are other changes, but can't currently remember them all.

One side issue is that the CO2 sensors at the base of your skull become dulled after a long series of breathholds or other activities that increase lactic acid buildup. at this point your brain doesn't respond until the pH of your blood drops lower than when at rest, allowing longer breathholds.

As a sideline, 2 trained Italian divers were recorded to have blood pressure measurements of up to 300/200 in the initial stages of a breathhold (with no adverse effects). Some individuals will respond faster, and others more slowly. They were the 2 daughters of a world record holder (Pelizzari?
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Thanks a lot for the comments, this is good advice. I tried some other techniques like only counting the time after the first contraction and on the first repetition even 15 seconds were painful and I stopped early but after five rounds I could go to like 45 seconds and it was fine. Maybe I just need more time at the beginning and start slowly. And I think it is absolutely crucial for me to have a completely empty colon. When I do anything high CO2, you can bet I have to go to the toilet afterwards if this is not the case. I think the CO2 stress is somehow affecting my intestines a lot.
For most of us it definitely does help to start slowly and work up. As you work up to harder breathholds it will pay big. It will also likely keep you diving, while many of those who always push the limits fall away from free diving.
Indeed, that is true. I have noticed that starting in slow steps makes it much easier to stick to a routine. I am really happy with my progress so far.
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