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C02 tables vs. 02 tables

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Dairyland diver
Apr 7, 2001
I have decided to start working on my statics over the past couple of weeks. I have been switching off between an 02 table on one day and a C02 table the next. I have been training about 6 days a week with the tables, plus about an hour a day in the pool.

My question is about the tables.

I can do a week #8 C02 table without much of a struggle. My tables only go up to week #8 so I haven't pushed them further- yet.

My problem is with the 02 tables. I have only done a week #5 once and it took me 100 contractions on my last static to make it. Usually, I can just barely make it through a week #4 02 table- only half of what my C02 table abilities are.

WHY is my 02 table time SOOO much worse than my C02 table time? My dive buddy can kick my butt at 02 tables and struggles much more with the C02 stuff than I do. He also only gets a few contractions on his longest statics, where as I can get up to 100.

Is there anything else I can do in my training program, or breath-ups, to balance this out? Should I be doing exhale statics instead of inhale statics for my 02 tables?

Any suggestions are welcome.

I have followed some of the other static's advice that I have found here and have had some good success with it.
Since I started exhaling some of my breath back into my cheeks during statics, to be used during the struggle phase, I have been able to jump my P.B. from 4:30 to 4:50 in a week. Thanks for the tip!:D I know 5 minutes, and more, are just around the corner with a bit more work. So far doing the tables once day has been my main focus on training for them. Now, I am looking for other things to add to that.

Hi Jon,
I haven't looked at the tables you are using but my thoughts would be to treat the 2 as seperate. To train, do as much as you are comfortable with in either one. I do CO2 tables and don't follow the 'rules' so much but just try and do as much as I can handle. If you find the CO2 tables easy, I suggest doing longer times.

Statics are a funny thing and what works for one person doesn't for another. Example my old training buddy would do a very similar warmup and breathing, similar static time, yet he would get contractions a minute later then me?! There was a thread somewhere talking about the differences between people with contractions. In one extreme, someone could do a 6 minute static, contractions starting at 2 min. On the other extreme some people are doing 7min+ statics with NO contractions.

Just accept that at the moment your buddy is better then you at one thing, and you at the other. It doesn't mean anything. People have different repsonses to CO2, some handle high CO2 better, some lower O2, some recover quicker after apnea. All these things will improve with training, but are also dependant on Genetics.

Exhale statics are very good training for low O2 tolerance. Even better is negative statics under water, but have to be very carefull with these. It's very easy to aproach Samba/Blackout without trying. Close supervision is needed. Also good for getting used to pressure at depth.

I think some of the 'Old School' training programmes I've seen, are a bit too rigid. They often have a lot of 'rules'. ie The 1min static = potential to dive 10m.....
If I would have believed that I would have limited myself. My best wet static is only 6.08, yet I have done 144m dynamic. I am by far weaker in statics, and I think you will find that some people can be much better in one event compared to another.

Being good at CO2 tables implies high levels of blood buffers, particularly bicarbonate.

Being bad at O2 tables implies either low hemoglobin, or an unusually high 'HVR' = hypoxic ventilatory response.

Trevor Hutton had a terrible time with O2 tables, despite going off the charts with CO2 tables. When he added repeated exhale statics, within a few weeks he could do the O2 tables easily. This implies that the O2 table itself is more of a diagnostic tool rather than a training tool, and that in his case, it was the exhale statics that actually caused him to improve his O2 tolerance, since he had been doing the O2 tables for ages without improvement.

Eric Fattah
BC, Canada
Thanks for the replies Walrus and Eric.

I do treat them as two seperate tables and only do one, or the other, on a specific day.

My buddy has been freediving for about 3 years and took a basic scuba course last summer, but hasn't doen any scuba diving since because it was boring. His 02 times are better than mine and he can hang on the bottom and stalk fish better than I can.

I have been scuba diving for close to 25 years now and I know that I am a C02 retainer as a result. I was wondering if this had something to do with the difference in my abilities with the tables. I may not be able to do the statics he can, but I can recover much quicker when we play underwater hockey and my dynamics are longer.

I have been off the scuba for a good 9 months now, (sounds like A.A.) and have no plans to go back to it. I thought that someone mentioned that scuba diving can really trash your freediving abilities. Is there any truth to that?

How should I go about these exhale statics? Normal breath up? Shortened breath up? 10 statics a day? 100 statics a day?

Can I do exhale statics and a C02 table on the same day, or should I still split them up between two spereate days? Can i also do statics every day, or should i only do them 4 days a week?

Thanks again,

Hi Jon,

lots of questions, I'll try and answer some of them. You don't want to do exhale statics before a CO2 table, otherwise you have already kicked the diving reflex in. You could do the exhales after the CO2 table, then you wouldn't need to warmup. In fact my PB exhale static I did straight after a CO2 table (dry). I did a 4 min CO2 table, followed by 2.20 hyperventilating, then did a 3.10 exhale static. They are very easy to do after a table, you have your full diving reflex kicked in, plus better CO2 tolerance.

How many ?
Don't know, I only do 4 or so a day, doesn't take long. I normally do something like, 1 min, 1.30, 2.00, 2.30. The first two are more like warm ups, the last 2 I can feel that I get a bit hypoxic. I wouldn't think you would want to do more then 10. To get a good training effect from them you do want to push them a bit. Not take it to right to Samba but close you definitely want to get hypoxic. You can do whatever rests you like. You don't need as long to recover as a normal static because you don't build up as much CO2. I do fairly short rests, say 1-2 minutes. I do hyperventilate a bit more then a normal static to delay contractions. They don't feel so good with an exhale static.

I don't see why you can't do them every day. Keep in mind if you really push your training you will need to pay more attention to diet, sleep more etc. Hope that helps, for really technical answers better off asking Eric. ;)

Oh and I forgot to mention, exhale statics are also good for warm ups. I use exhale statics/negatives to prepare for a deep dive or a dynamic. Negatives kick in your diving reflex even more due to the simulated pressure.

I scuba dive and freedive and have never had any problems. I did see something about breathing pure O2 can have a negative effect on your apnea abillity. So possibly Tech diving whilst using Nitrox or 50/50 O2 for deco might do the same ?
Thanks Wal,

I was wondering about how many because they go so much faster than my old 02 tables. My 02 table involved 8 breath holds and took about 50minutes. With the C02 tables i could do 8 breath holds OR keep doing them until I hit 50 minutes. The shorter hold, and breath-up, allow for more repitions.

It sounds like you get contractions. I know that i certainly get them, but thought that Eric said you shouldn'y get them if done properly?? I might have misread that part. How many contractions do you hold for? I have been holding for 30 on exhales, and up to 100 on inhales. I don't know that I could ever go through 4 minutes of contractions like Martin can- but sure wish I could!

What kind of a breath-up are you doing? Just a minute of hyperventilation? Or a full blown 2-3 minute work up?

I already do some negative's to warm up when I am out on the lake/ocean. I have noticed that it kicks things in gear at a faster rate. I also practice 3-4 of them every time I am in the pool swimming laps- to get used to the pressure.

How have you changed your diet??

What is an O2 table and can someone provide an example/link to where I can find one. Thanks

Brad :martial
Check out the FREEDIVE UK website. They have static tables that you can download onto your computer.

A C02 table has you do a series of breath holds with shorter and shorter breath-up times inbetween each breath-hold.

One table might have you do a series of 2:00 breath holds. The first time you do it your allowed to breath-up for 2 minutes. By time that your at the end of your table you are only allowed to breath for :30 inbetween each 2:00 breathold.

This is a vauge example, but if you check out FREEDIVE UK you'll see how they work.

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A word of warning; CO2 tables have a habit of causing CO2 headaches, but there is an easy way to avoid CO2 headaches.

Simple: do jalandhara bandha. The yogis were not stupid, and they were adamant that any apnea (kumbhaka) over 30 seconds must be accompanied by jalandhara bandha, to 'prevent excessive pressure in the head.'

To do jalandhara, touch your chin to your chest while sitting (don't hunch your back! keep your back straight).

More specifically, inhale, swallow, then touch your chin to your chest as high and tightly as you can. This squeezes the carotid arteries to prevent the BP in your head from going too high. This cannot be done while lying down, another reason why the yogis insist on using a sitting posture for apnea.

I once did a CO2 table which consisted of 1'45-2'00 apneas separated by a single breath in between, for about 30 consecutive apneas, after which my expired CO2 was over 10%. I had a migraine for 20 minutes afterwards. Now, I do the same table with jalandhara bandha, with no headache at all.

Gotta listen to them yogis.

Uddiyana bandha and mula bandha also have uses in the late contraction stage.

Eric Fattah
BC, Canada
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Thanks Eric!

I always knew to tuck my chin, but I had no idea it had a yoga background to it. I thought that it just help relieve the pressure on the throat while holding your breath. I have also been doing it while both seated and lying down. I wasn't aware that it worked better in one position over another.

When are you coming out with that book?:confused: ;)

Your head should be at 90 degrees to your body during jalandhara.

One way to learn it is this. Laying on your back, raise your torso and legs straight up, so you are kind of doing a headstand, except your head is 'folded' and you're really doing a neckstand like this:

-- feet
-O head

That is how the yogis learn & perfect jalandhara. It takes significant muscular energy to do. If you can do it without muscular effort, then you are not doing it strongly enough. That is why I don't do it on 'max' attempts, except maybe near the end, because it drains O2.

Eric Fattah
BC, Canada
Good enough of an explanation. Thanks man.

30 apneas for 1:45 to 2:00 with one breath in between! That's crazy man.

Props to you both.

Brad :martial
What if I am lying flat on my back and prop my headinto that position with pillows??

On the other topic, of C02 tables, I read on an Underwater Hockey site about "minute breathing". You take 1 breath a minute for 20 minutes. If you can't do a whole minute at first you can start with 1 breath every :30 and work your way up to whatever kind of torture that Eric plans on doing.;)

Doing 16:64:32 pranayama is one breath every 1 minute 52 seconds. The longest I have kept that up is 35 minutes before I got a contraction (you are not supposed to do nadi shodhana with contractions).

Eric Fattah
BC, Canada
Apnea walking and headaches

Eric- I just started apnea walking and after my pb of 2 minutes I had quite a headache. How can I stop this from happening in the future? By the way, how is the tendonitis coming along?
I do jalandhara bandha even while doing cardio-apnea, such as apnea stairmaister. Prevents the headache, but it might look a bit awkward.

As far as the tendonitis goes, I did 2 dynamics with my monofin the other day, which was the first day I had put on the monofin in months. To make a long story short, it seems the tendonitis is 95% gone, but until it is 100% gone, using the mono would only aggravate it, so I will wait a while longer.

Eric Fattah
BC, Canada
one more question

Hi guys!

This is a great thread. I started doing co2 i o2 tables four weeks ago. And I can see some progress, especially in my co2 tables.

My guestion is this: How long sholud the breathold be on the co2 and o2 tables?

40%, 50%, 60% of my max breathold time or what?

My PB static is 5:15, and I do o2 table starting with 2:00 breathold and finishing with 4:20. Increasing next static by 0:20, rest period is always 2:00. On the last static I have 20 contraction (30 is my max number of contraction).
My co2 table looks like this. I start with 2:00 breathup and then I do 2:15 static. Static time remains the same and I decrease rest time by 0:15. I do the last static with 0:15 rest time and I have 15 contractions.

My goal is to hit 6:00 static regularly. Am I on the right track?

Greetings from Israel to the honored citizens of this forum.

As you can guess, I am a newbie to the sport, or hobby, or business, or lifestyle - whatever do you consider it to be.

I have been utilizing the above mentioned tables for two weeks now. Problem being, these tables only help me achieve relatively confident performance at lower durations. For instance, I am able to use the CO2 table at roughly the same conditions as Svilko, without getting contractions. As for the O2 one - I'm perfectly calm and in control until about 2:50. By 3:00, contractions start, yet these, too, are rather mild, predictable and thus controllable. However, immediately after 4 minutes and 10 seconds, I can literally feel the symptoms of a so-called samba, accompanied by strong feeling of skull pressure, my vision blurs and I have to stop. These symptoms appear suddenly - over the course of no more than five seconds.

While many potential physiology-related causes may be involved, I am doubtful that they are completely unsurpassable. Somehow, it just doesn't seem realistic that I'm able to perform rather well precisely up to 4 minutes and ten seconds (Never even twelve), especially taking into account the variations between breaths, which should exist. And they exist - for instance, at times, the contractions commence sooner, at times later, and yet, suspiciously, the final result remains the same, and I don't consider this to be a result of a psychological barrier.

Hence, I would like to ask you for an advice. What might cause it - carbon dioxide build-up (hence, the headache) or the lack of oxygen (hence, the 'fade to black'), and whether there is a form of exercise that might help me past this limit.

Thank you for your time.

- Levi.
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You are a newbie to the sport and can already do 4 minute dry statics? That is impressive my friend. To get past these limitations keep practicing. Your body and mind will adapt to longer apneas. I still can't get over a 4 minute dry static after two weeks of training. Who knows, one day you might be representing on some freedive team. Train hard, dive safe and welcome to the forum.

Brad :martial
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