Freediving beginner questions!

[Kars]

Well Lambe, now your personal best is 3 minutes, your Table A time is 1'30". The surface times remain the same.

Your body need time to learn to react softly to the increased CO2 and lower O2. You can calm your heart down by 'talking to your heart' - visualise your heart in your mind going slow, relaxed and smooth. With the Table A you know for certain O2 is all-right, and you can focus on relaxing through the CO2.

Like Reeftroll remarks, the first ones can be a bit tough, but once you get into the groove, it's easy and very satisfying to complete the schedule.

You'll notice that if you do a dynamic afterwards it will be much easier too. But make sure you have a buddy, since your CO2 tolerance has grown and the alarm shifted.

I've not tested out the Apnea.cz tables, but will look into it. I just registered.
What I gave you is the classic Table A - CO2 schedule.
Remember that tables and exercises need to be adjusted for the form of the day. When you feel like ***** start very easy and slow and do not stare blind on the numbers.
Later on I'll give you the more intermediate 'schedules' I used that have this in mind, useful for when you get to the 5 minute level.

Reeftroll say high to Benny from me, I met him a few times and he's a fine example of a jolly good bloke - Deep diver too!

 

[ReefTroll]

I will mate. he seems like a great guy, and I'm really looking forward to the course. It just happens to be in a beautiful spot also!

 

[lambe]

1:48 was a bit too hard on me I think, but yeah I guess 1:30 would be perfect, I'll try it out!

So basically, I can hold my breath for however long I can, then breathe for about 15-30sec and theoretically hold my breath for the same time? It's just the amount of increased CO2 that is stopping me? But a stubborn person like me "could" do it? Maybe not the exact same time because my pulls would probably be higher by the second time but about the same, you get my point?

I mean when I train DNF and do the 25m then 1min break I could push myself even more and it's not even dangerous because my O2 is still there? The only thing I'm experiencing is the lack of CO2? hehe thought it would be best asking before I'm diving today hehe

Edit:

I just ran through the training schedule there, the one from Kars. It was funny, I found the first ones harder, until I relaxed and let my mind go somewhere else.

That's exactly what I was thinking! I started out and thought, oh man I'm not gonna make this but as the time went by and it got harder and harder it seems like my body adapts to the increased CO2 and loss of O2 and it was almost easier All thought that last challenge was hell!

 

[Johan Andersson]

So basically, I can hold my breath for however long I can, then breathe for about 15-30sec and theoretically hold my breath for the same time? It's just the amount of increased CO2 that is stopping me? But a stubborn person like me "could" do it?

Well, not in all circumstances, especially not when diving in water. With too short recovery intervals between apneas, O2 stores are also affected. You need more than 15-30 sec to replenish the O2 stores completely. There have been accidents in which too short surface intervals in between dives probably contributed to the accident.

If you understand swedish (lambe is from Sweden), you can have a look at this text about a fatal accident involving short surface intervals: Robins mamma försöker förstå...

/Johan

 

[azapa]

I can't understand Sweedish Johan, but that suunto graphic is very clear! red dot is blackout point, after that victim sinks to bottom until rescued. Before red dot the seems to be 3 20ish dives in less than 5mins. that must have been one or two breath surface times only?

 

[Johan Andersson]

I can't understand Sweedish Johan, but that suunto graphic is very clear! red dot is blackout point, after that victim sinks to bottom until rescued. Before red dot the seems to be 3 20ish dives in less than 5mins. that must have been one or two breath surface times only?

Surface times were 10-15 s (approximated). Of course, this was situation completely different to what has been discussed previously in this thread, but I just wanted to point out that it is not safe to assume that short intervals will not affect the O2 stores. At least not when combining apnea with exercise (swimming) and changes in ambient pressure (diving repeatedly to depth).

/Johan

 

[Kars]

Like Johan said, though O2 is relatively quickly replenished (something like 2-3 breaths to get to 90% SaO2), there is no magic formula I know of that let's you do 10 minutes.
The example is from a person diving deep, that brings a whole new set of dynamics to the table that reduces the O2 replenishing ability.

However the CO2 schedule is designed to make use of the principle that O2 replenishes faster than CO2.

"I mean when I train DNF and do the 25m then 1min break I could push myself even more and it's not even dangerous because my O2 is still there? The only thing I'm experiencing is the lack of CO2? hehe thought it would be best asking before I'm diving today hehe"

I'm sorry to say but this is a totally confusing mess. Precision is important. You see me editing my own text many times because I spot things to improve and be careful to be clear and not misleading.

Let's take the first sentence:

"I mean when I train DNF and do the 25m then 1min break I could push myself even more and it's not even dangerous because my O2 is still there? "

My question to you, what do you understand on pushing more? Pushing for more 25m lanes? or pushing for longer than 25m lanes?

The next:

"The only thing I'm experiencing is the lack of CO2?"

I hope this is a typo and you meant to say: "The only thing I'm experiencing is the accumulation of CO2?" - Much better even though it is not the complete story as Johan points out.

I totally subscribe to this:

"hehe thought it would be best asking before I'm diving today hehe"

What happens when you do repeated 25m dives - since these are easy for you when not repeating with short intervals - is that you have enough ventilation to replenish the O2, but are a little short on normalising the CO2 level. This will cause the next dive to feel more difficult, which in turn deteriorate your swim efficiency, thus costing you more O2 than the previous dive. Also your 'anaerobe buffers' are getting soaked dry making swimming again more difficult and less efficient, costing more O2.
So you see doing a CO2 schedule in dynamic is different to static.

Since your pb DNF is 50m, I think you can do a small CO2 schedule with fins, swimming 25m in between a fixed start time (rest). It's the infamous 16x50m style training with less distance.

Keep in mind the above and you can try with fins for:

Apnea, 25m
start* every 1'30" (next start at 3' - 4'30" - 6' etc.)
10 lanes - 250m in total

* if you swim too slow you'll have less recovery time, find a good balance.

Have your safety/buddy walk/swim along you, timing your dives, doing the countdown to the next start, and giving you 1 or 2 technique directions at each stop. Technique directions are about streamlining, relaxation, fin technique recovery breathing etc.
Yourself can focus on the above and also recognising the sensations I describe above - lactic acid build up, CO2, contractions, etc.
Like in static, keep relaxing your body and mind despite the higher CO2, fatigue etc.
Through this exercise you'll learn the above plus very efficient swimming, knowing that wasteful swimming produces more CO2 and consumes more O2.

It's fun to do, you can learn a lot in a short training time.

Please give yourself a freediver course and learn proper safety techniques, especially when it gets easier to push yourself further. Until than limit yourself to "the first contraction" in combination without hyperventilation.

Please Johan and Apaza correct and supplement me when I'm wrong or lacking.

 

[Johan Andersson]

...O2 is relatively quickly replenished (something like 2-3 breaths to get to 90% SaO2)...

True, and that reflects the quick restoration of the lung O2 store. However, for the venous O2 store, recovery time is much longer. I don't have the exact time in my head and do not have access to the data where I am right now, but it's a matter of minutes. So repeating apneas with too short intervals may eventually lead to a shortage of O2.

/Johan

 

[azapa]

Johan, we typically teach spearos a 2 to 3 times dive time as recovery time on "normal" dives. I guess that is the minutes you are referring to (and is a very easy to teach/remember rule). Personally, spearing, I can never rest less than 5:00 for most dives 1:30 to 2:00. I just don't feel ready before that.

 

[trux]

Yes, I second Jonas. Replenishing the arterial hemoglobin is no problem, and it happens almost instantly. However, it tells nothing about your O2 stores. The newly bound O2 continues to be consumed with a very high rate after an effort - O2 is used to break down acid lactic, to recharge myoglobin,... and so it indeed takes much longer than just a few breaths to get to the state you are really ready for a long dive

 

[lambe]

If you understand swedish (lambe is from Sweden), you can have a look at this text about a fatal accident involving short surface intervals: Robins mamma försöker förstå...
/Johan

Felt terrible reading this, but thanks for sharing. I just somehow feel that it could have been me just as likely as him:/

I'm sorry to say but this is a totally confusing mess. Precision is important. You see me editing my own text many times because I spot things to improve and be careful to be clear and not misleading.


What happens when you do repeated 25m dives - since these are easy for you when not repeating with short intervals - is that you have enough ventilation to replenish the O2, but are a little short on normalising the CO2 level. This will cause the next dive to feel more difficult, which in turn deteriorate your swim efficiency, thus costing you more O2 than the previous dive. Also your 'anaerobe buffers' are getting soaked dry making swimming again more difficult and less efficient, costing more O2.
So you see doing a CO2 schedule in dynamic is different to static.
.

I'm sorry Kars, reading the text myself I see it is very confusing.

What I was really asking was how long surface time I needed to be recovered from a 25m dnf dive. I wanted to push myself with smaller intervals to gain a better training, that's it. My mistake was that I was comparing static apnea and dynamic. I thought that maybe I could rest 15-30 sec after each dive and that there were no danger in it, just the annoying pain of increased CO2. I understand now thanks to your explanation You didn't know what I was wondering about and yet you answered it

Also if I understand hyperventilation correctly: I can make a better time/distance if I don't hyperventilate sense it drains O2. Only bad part is that I will have a much bigger urge to breathe feeling, correct?

About the freediving course, I would love to take one but they are all very far away and there for it's kinda expensive so I guess I'm forced to wait unfortunately

Edit: Exactly Trux and Azapa, that's the information I was wondering about many thanks!

 

[trux]

What I was really asking was how long surface time I needed to be recovered from a 25m dnf dive.

Nobody will tell you. There are people who can swim hundreds of 25m DNF lengths with just a single breath in between, while others may black out just after a singe length. And not only different people, but also different days at the same person play a role. So do not ask how long you need to to rest between dives to stay safe. Ask how many buddies you need to stay safe. I'd tell at least one very experienced, reliable, and vigilant buddy is sufficient. Anything less is a Russian roulette.

 

[lambe]

Nobody will tell you. There are people who can swim hundreds of 25m DNF lengths with just a single breath in between, while others may black out just after a singe length. And not only different people, but also different days at the same person play a role. So do not ask how long you need to to rest between dives to stay safe. Ask how many buddies you need to stay safe. I'd tell at least one very experienced, reliable, and vigilant buddy is sufficient. Anything less is a Russian roulette.

I understand yeah I noticed that, was really not feeling very well today while I was swimming Guess it's just a bad day or I might come down with a flue or something.. Anyway I'll wait until next time Hope it will be better!

 

[Johan Andersson]

Johan, we typically teach spearos a 2 to 3 times dive time as recovery time on "normal" dives. I guess that is the minutes you are referring to (and is a very easy to teach/remember rule). Personally, spearing, I can never rest less than 5:00 for most dives 1:30 to 2:00. I just don't feel ready before that.

I think this may be a pattern with enough safety margin (assuming these dives are not very strenuous) with regard to O2. Stick to that and you are most likely on the safe side. The recovery time for O2 is faster than the time for recovery of CO2. Your feeling of not being ready before 5 min I suspect is not primarily related to O2 recovery (more likely CO2). My colleague Mats Linér studied the time constants for recovery of O2 and CO2 after 75 sec dives to 20 m (in a hyperbaric chamber). He concluded that a surface time of approximately 180 sec would have been enough to prevent CO2 retention over successive dives in that study. A surface time of approximately 80 sec would have been enough to prevent O2 depletion over successive dives.
Tissue oxygen and carbon dioxide stores and breath... [J Appl Physiol. 1994] - PubMed result

In this context I find it interesting to learn from the experiences of "naturally diving populations". Of these, most of us have read about or heard of the Ama divers. An classical account of their diving pattern is given in this study:
Diving pattern, lung volumes, and alveolar gas of the Korean diving woman (ama)

A quote from that study:
"The unassisted ama dives for 30 sec, rests for 30 sec and thus accomplishes in 1 hr approximately 60 dives to a depth of 5 m. The assisted ama, on the other hand, dives for 1 min, rests for 1 min, and accomplishes approximately 30 dives in 1 hr to a depth of 15-20 m."

/Johan

 

[azapa]

thanks for your input on this thread Johan. One of the reasons I wanted to become an instructor is to help local spearos here.

It seems to be a world standard for spearos that they don't rest enough between dives. 1 minute is the norm (yes, regardless of stress of previous dive). Some even worse, just count breaths between dives "5 to 7" being what I hear often....

On an average 4 hour spearing comp I can manage 40 dives (a lot for me) most suunto's I see of other divers there are an incredible 100 to 120 dives. Crazy.

The selling point I try to make to them, is that 40 comfortable and safe dives can often result in more fish than there 120 frantic ones. This way they will listen!

 

[lambe]

Johan Andersson: Great information! Thanks a lot for sharing

 

[Kars]

No Problems Lambe, I'm just careful because people are fragile, and freediving is a fragile sport when it comes to public opinion. It's easy to degenerate the sport, and it's difficult to explain the the benefits.

The difference between a hyperventilated dive and a normal dive is:

Hyperventilated - done in modest amount covering 50m DNF:
High Heart-rate stressed start - extended easy phase to say 30m, then HARD hit by CO2 and contractions - very hard to deal with. Coming up (if in time) with clouded mind, LOW on O2, while muscles are not much used.

NON Hyperventilated - covering 50m DNF:
Low Heart-rate relaxed start - normal easy phase to say 20m, then GRADUAL CO2 build up and difficulty and with controllable contractions. Coming up with much clearer mind, while muscles heavy on lactic acid.

Functional Residue Diving would enlarge the difference even further.

As an option you could invite an experienced freediver from the neighbourhood to come over for a weekend, and have a few training sessions together. You just spoil him with nice food, a bed, your admiration and maybe some travel expenses and enjoy his safety and training knowledge. Or you come over to his place for a day or two and I'm sure many like to teach you the proper safety techniques for a very affordable price.

At which part of Sweden are you?

To add the O2-recovery time question: if your remaining in the aerobic phase, than the recovery is very quick. When you use the anaerobic abilities, than it takes much longer to fully recover.

Now for my bodytype I happen to have a long aerobic phase. The disadvantage is that it cost me more O2, and my dives are limited by the amount of O2 that remains for my brain. So 'm pretty good in 16x50 6th time ever. But I relatively 'suck' in dynamic with a pb of just 150. Now I understand my body a bit better, I adjusted my tactic, and consequently a new pb.

 

[lambe]

I understand, and I'll be more careful in the future

I live in Sölvesborg, southern part of Sweden. Solvesborg sweden - Google Maps

Sadly, I don't really know any friends that are even interested in freediving or diving for that matter. The nearest place to freedive would be Karlshamn, which is about 20-30min drive from here. I took my diving license there and that's when I got in contact with freediving for the first time. They don't have a freediving course or club or anything I don't believe, but they do have a underwater rugby team which was fun and all but it's not freediving
That's why I always dive here in Sölvesborg or in Bromölla which is only 10min from here. The deepest part of the pool is about 1.7m or something, but at least I can do dynamics and static

 

[Kars]

Well you could consider contacting Christian Engelbrecht - a Dane in exile , on Deeperblue too, he now lives in Kårestad, about 80 km North of you. Considering the buses are very affordable you may want to contact him and share some weekend of quality water time. I would use my moped.

Spread the word around and you'll find a way.

 

[Johan Andersson]

lambe, you could also register here: OO Natfridykaren

It's a swedish forum where you can find people to dive with. There are some divers in the very south of Sweden (in Skåne).

/Johan