cardiovascualr fitness?

[efattah]

Wal,

Some answers:

- Your lungs can almost never get over 18.5% O2, even with brutal hyperventilation. Trust me, I've tried it with an O2 monitor. Keep in mind that as you inhale, you also saturate the air with water vapor which takes up a few percent. Given that during extreme hyperventilation, you might get down to 2.0% CO2, then that puts the upper limit at 19% O2 even without water vapour. In reality you'll start a dive at around 3.5 to 4.2% CO2, any less and you'll be too hypocapnic. At 4% CO2 your max O2 is 16-17%.

- I think your blood oxygen store is just as usable as your lung store. Think of it this way: at SaO2 = 50%, the amount of oxygen in one ml of blood is different, depending on your hemoglobin level. A person with 21 g/dl has 50% more O2 per ml compared to someone with 14 g/dl, and that is true for all saturations of hemoglobin. So it seems to me that the SaO2 blackout point would decrease as your hemoglobin concentration increases.

As a further example, imagine someone extremely anemic with just 3 or 4 g/dl of hemoglobin. In such a person their hemoglobin would have to be almost 100% saturated with oxygen just to remain conscious. So, to generalize that all people black out around 50% SaO2 seems wrong, because it seems to depend strongly on your hemoglobin level.

 

[Walrus]

Makes sense, thanks Eric.
So to work out useable blood oxygen might be something like (using your example).

Case 1 - 5L @ 14 g/dl = 938ml O2 (Blackout at %50 Sao2 for example) so useable = 938ml/2 = 469ml, so for this person +469ml of O2 in blood required to keep conscious.

Case 2 - 6L @ 21 g/dl = 1688.4 ml O2
useable = 1688.4 ml - 469ml = 1219ml

Although this would indicate a blackout level of %28 SaO2, sounds extremely low. Has Seb, you or anyone ever worked out/ measured this?
ie %SaO2 aproaching blackout with raised hemoglobin, vs 'normal' levels.

Cheers,
Wal

 

[quasimoto]

ok this has all taught me a lot, but i have a couple questions:

first, what is the difference between hematocrit and hemoglobin, and which results from what type of training and which is more beneficial?
my second question is, can i do frc training to raise my hematocrit levels and have it be beneficial to full lung breath holds?

I ask because currently my only training whatsoever is 1-2 max breath holds per night, and i have improved from the low 5's to consistant high 5's and a couple 6 minute plus statics, with no other training. however i know i will hit a plateau soon, and was wondering what would be most beneficial from there to progress to over 7 minutes.

thanks in advance for your replies
rory

 

[efattah]

quasimoto,

1. So far my FRC training has improved my inhale dives/statics etc...

2. You don't need to do FRC training to get huge hemoglobin & hematocrit. It can be done on inhales if you train hard enough. However, static apnea (either FRC or inhale) may never allow you reach your max, simply because the accumulation of waste products during static is different than in active breath-hold exercise; it seems that huge statics cause overtraining very fast, and yet without extreme hypoxia your blood won't improve (not to mention you need good iron status).

3. Relationship between hemoglobin & hematocrit:

There is no direct relationship, because it depends on the average size of the red blood cell. A rule of thumb is that a hemoglobin level of 17-18 g/dl is around a hematocrit of 50%, but it could vary from 46-52% (just guessing). Hematocrit is the volume fraction of blood made up of red cells. It is measured by taking a blood sample, and then running the test tube in a centrifuge until all the red cells 'clump' in the bottom of the test tube. Then, you measure the total volume fraction taken up by the clump. Hemoglobin, on the other hand, is stored inside the red blood cells.

The ultimate oxygen carrying capacity of your blood is measured by the hemoglobin concentration (in grams per decilitre of blood = g/dl), and sometimes it is expressed in grams per L (g/L).

A simple home blood analyzer like the one I have (Hemocue B-Hemoglobin), can only measure hemoglobin, not hematocrit.

 

[Bill]

G'day Wal
This stuff makes some interesting reading. I get to day-dreaming of what would be possible with 11 L of lungs.
I'm not trying to disagree with all the above, but there are one or two things that don't jibe. If you remember the doctor that argued with Seb on at least two sites, he used some different figures. I can't quote him, just refer to my notes. His example used a blood O2 capacity of of 1000 ml as you did, but he claimed that 70% was useable. He also mentioned that another 300 ml of O2 was stored in the body. I think it was in the muscles and/or in solution. It just changes your numbers, not your arguement.
This is getting to sound like cycling. When I got comfortable with the long aerobic rides they made me start interval training. At least I'll be able to dive with Martin in a few weeks. Maybe he'll tell me some good training secrets too.
Aloha
Bill

 

[efattah]

Bill,

Apparently Martin has started some sort of new training as well, maybe he'll cough it up when you see him...

It would appear to me that there is a widespread 're-thinking' of training methodologies, and the so-called 'old-school' approaches are being replaced by newer experimental methods.

 

[Walrus]

Aloha Bill!
The exact numbers weren't important, was trying to show that the hemoglobin level for a diver that already uses a lot of packing is less important then for a FRC diver. I have yet to see a viable alternative to good static & dynamic performances without using packing. Like I mentioned before, for a competition diver this is 2/3 of your total points.

I read a funny quote from a European diver after doing one of Seb's courses. He got a new PB by using a 'Hybrid' aproach of something in between FRC and inhale + packing. He used full inhale, no packing with No hyperventilation.
Hmm I think apnea academy teaches that, in fact I think people were doing that a long time ago.

What's new is old, and what's old is new again

 

[ADR]

...and Wal to be fair to Seb, if comp diving with the current 3 disciplines and points system is your thing then he does not suggest his approach...never has!!

 

[ADR]

Bill,

Apparently Martin has started some sort of new training as well, maybe he'll cough it up when you see him...

Eric, what are the jungle whispers saying??

 

[Walrus]

I was just getting back to the original purpose of the thread. The effects of cardio on diving performance totally varies on your diving aproach. I didn't want to get into aproach A is better then B. I just wanted to point out there are people out there already using A or B, C.... X.
So with the 2 extremes of FRC diving and TLC + packing, the negative effects of cardio on perfomance would be hugely different. ie much less negative effects on a TLC + packing diver.

It's not just competition/apnea type divers. Realise that there are a lot of people starting out reading these threads are impressed by people doing 10min+ statics, and 200m dynamics and consider this all part of 'freediving'. So have to be careful when some people are refering to freediving as just 'constant ballast' and others are talking about all apnea categories.

Cheers,
Wal

 

[jome]

Walrus, I was thinking about that the other day. Doesn't Umberto teach something like "only 70% inhale on a depth dive", or maybe it was static. Isn't that in essence what the FRC fuss is all about? Or atleast a close "hybrid" like you said.

Anyway, this is interesting stuff...

 

[ADR]

Jome,

I think you are right and it's in his book as well (maybe). My foggy memory is 70-80% for static as relaxation is more important than max O2 store and close to 100% (no packing) for depth.

 

[Bill]

Eric
It looks like they'll be here for a week. I'll do my best. If I don't have any luck, maybe my wife can pry some info out of Juliana.

 

[ADR]

Hi Bill,

Martin likes a beer remember! Last time I had a beer with Martin and Kirk we had a great conversation about Seb and FRC.... :friday

 

[sebastien murat]

Hi all,

Just a couple of points:

Elevated blood O2 stores are important for serial/bout dives on 'empty' lungs. This is because the working muscles need to be kept predominatly aerobic for maximizing bottom time to recovery. At the time I was doing intensive dynamic intervals I developed a particularly elevated haematocrit. However, after some time I opted to chang tact. Instead of fosusing on enhancing oxygen stores I looked to ways of minimizing O2 consumption by sensitizing the dive response. I did this by undertaking a regime of almost daily singular maximum dives. Needless to say my haematocrit returned to quite normal levels (~mid 40s). Despite, my reduced O2 stores however, my maximum perfs. increased considerably beyond what I'd ever managed to achieve while doing intervals.

My take on the present state of affairs is this: if you want to dive deep/far on inhale you must essentially rely on increasing you O2 stores by increasing your aerobic scope. As we all know there are some serious (deleterious) conditions associated with this, especially for deep diving. On the other hand, if you choose to walk the road less travelled you should look to the 'less is more' approach.

Regarding Peli's school, I'm unfamiliar with his approach but from waht William Trubridge (Apnea Academy Instructor/ Manual of Freediving English Translator) has told me it is clear that they are of the opinion that 'empty' lung diving is crazy stuff and best left for the animals.


Sebastien Murat
Townsville, Aust.

 

[octopus]

I cannot quite follow the discussion without additional explanations, as I have not been into all this body bio-chemistry stuff for too long. If there are more forum members like me...well, there are some usefull links:

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookRESPSYS.html

http://library.thinkquest.org/17963/respiratory-system.html

http://explorebiodiversity.com/Hawaii/BiodiversityForgotten/Wildlife/cetaceans/adaptations.htm

http://www.cartage.org.lb/en/themes/Sciences/Zoology/AnimalPhysiology/Respiration/Respiration.htm

http://faculty.clintoncc.suny.edu/f...ems/Respiratory System/Respiratory System.htm