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Get high and get on down: a response

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Hi Pablo,

Many people might think that the trolley in the background with bumble bee insignia belongs to my 3yr old but I'm impressed that you recognise it as my DIR tech diving transport mechanism :)

The exhaled air does actually go to the bladder prior to the scrubber and most condensation does occur there and only occurs at the scrubber after I stop the session. I'm going to add some water traps in both tubes just to be safe and also keep an eye on the scrubber during use given that it is clear plastic. I'll also add a water trap in the bottom of the scrubber for a "belt and bracers" approach to safety.

thanks for the tips


how many hour long sessions did Mark undertake during those 3 weeks? you said that Mark's Hb didn't increase during that time. is that unusual after such treatment? what kind of increase would you normally expect? what is the maximum rate of increase in Hb given a strong enough hypoxic stress and adequate diet?

thanks for writing these articles - very interesting.
well done for rowing across the pond - respect.

Mark did 15 x 1 hour sessions. 5 minutes hypoxic, 5 minutes ambient air. In carefully controlled scientific studies (such as the one conducted by Dr John Hellemans with Lincoln University, New Zealand) elite level athletes increased their hemoglobin (number of red blood cells) levels by 2.5% and hematocrit (% of red blood cells) by 3.6% and reticulocytes (young red blood cells) by 14.6% following a 3 week course of IHT (15 sessions). Blood parameters are commonly studied to indicate physiological changes, however the story is a lot more complicated than that, and still not fully understood. People adapt to cope with reduced oxygen in different ways and blood parameters are just one adaptation mechanism displayed. To understand it fully you have to look at it from a sub cellular level and it gets a bit more complicated there.

If you purely want to see changes in Hemoglobin, make sure you eat lots of spinach to keep your iron levels high!


interesting. 2.5%... that's less than i expected. that's like increasing from 15.0 to 15.4 g/dl. you'd need a pretty accurate instrument to pick up that change!

how long would you expect it to take for the effect to be reversed (or 90% reversed) after the end of the course? can you put a rough figure on that?
2.5% is quite significant if you are looking to eclipse a record. This is a mean score, taken from a group of athletes, some individuals rose more, some less. Hemoglobin is not the only parameter you should look to increase to improve your tolerance to hypoxia. In answer to the second part of your question, Red blood cells last for 90 days, so in theory you should benefit for 3 months. In practice you are at your peak for the a month after you stop the stimulus, some say you should use IHT right up to a competition, other say you should stop a week before competition, again it is up to the individual.

Sorry no more questions. Some of us have work to do!

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A few specifics about my blood analysis ( as I was the guinea pig ):

Final readings -

Haemoglobin G/Dl - 14.9

Red Cell count - 4.36 x10^12/L ( don't ask me what the units are, but it's a low value )

Haematocrit - 0.416 ( also low )

MCH - 34.1 PG ( high )

MCHC - 35.8 G/DL ( high )

I didn't have a pre-training test to compare, but Alun had measured my haemoglobin levels in July, and they were about the same ( if not slightly more ).

As Richard suggests, the blood tests in their own right are inconclusive - it looks like something else is happening at the cellular level to account for the increased buffering tolerance.

Something for someone somewhere to research?
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This is an incredibly interesting thread and the article by Richard was equally interesting. Sebastien achievement of maintaining 63% Hct amazing! Sebastien, are you saying you achieved this through dry empty lung breatholds? I thought you spent a huge amount of time in the water. If your Hct success was through dry, empty lung statics, then that is inspiring because it means anyone has the tools needed to do!

A question, if one does negative pack, dry statics, will there be a negative pressure in the lungs and thus make PaO2 less than ambient?

PS Andy, awesome job of making your own hypoxicator. Let us know how it works for you.

Personally, I don't do any dry apneas as it isn't specific enough for what I do; I' into actual diving and not statics for theior own sake. My adaptations are therefore all water-based. Nevertheless, it would still be possible to achieve an elevated Hct dry. Nevertheless, the dive response in the dry, which can be trained, is not well developed. A strong dive response may, on the other hand, make reaching low PaO2 more difficult since the muscles can tire quickly, if one is exercising, as these shift from aerobic to anaerobic metabolism. A strong dive response should be sought (exhale apnea + exercise + cold water) if one wants to develop elevated MbO2 stores since the muscles will run out of O2 very quickly.

PaO2 is always less than ambient except during descents to depth. Even then it will inevitably drop also.

Observations and asking for Help

I have been playing with this over the last two days. If Mark Harris can increase his time from 6:30 to 7:00 in three weeks, and Sebastian Murat and Eric Fattah say it can be done with empty lung dry statics, I can’t help but be interested! :)

I decided to do it each day for seven sets, because that’s what how many sets it looked like Richard Pullan had Mark Harris do from the graph in the article. I decided to speed up the process by fully forcefully exhaling and then doing 3 negative packs. Since I have a spirometer I’m used to fully exhaling so I know my lungs were to residual. I could definitely feel the negative pressure on my lungs and thorax after the three negative packs and it was a little uncomfortable.

The first day I took my SaO2 down to 83% 7 times. I took between 1:31 and 1:56 to achieve this with the high of 1:56 on the third static. My times were bell shape if you were to graph them.

Today was the second day and it was my goal to go down to 80% seven times. But my body must have had different plans, because starting with the first static at about 30 seconds I started having terrible contractions. With the negative pressure, it felt like my inside was going to implode! :waterwork This was with Sebastian’s recommendation of hyperventilating before hand to lower CO2. I bailed out at 56 seconds with only a 98% on the oximeter. I could only manage 98% on the second set too, but this time it was for 1:23.

With the third set the contractions finally subsided to where the pain was manageable, although I am worried what my assistant on the other side of the close door at work is thinking of me now! The noises, I couldn’t help but make, trying to last through the contractions with negative pressure- sounded terrible! This time I made it to 2:10 before hitting 83% SaO2. The 4th through 7th holds I held until 80%.

I don’t necessary think that the contracts were a result of doing them a second day. It maybe, but I have experienced some days where contractions were just plain severe for no reason I could conclude. I’ve noticed that if I can muster the strength to continue on those days, I usually get pretty good results, but sometimes its more than I can bear.

Another thing I have noticed is that my SaO2 stays pretty high, but when it gets past about 93% it falls like a rock. It’s even hard some times to stop the stop watch when it reaches 83% or 80% it’s falling so fast.

Observations and recommendations please! Should I just passively exhale and forego the negatives? Can having contractions with negative lung pressure hurt me? :crutch
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one thing to bear in mind is that Mark could have breathed normal air during those IHT sessions and still have done 7mins at the end of it! when i used to do static years ago i beat my PB by about 15-20secs on a few occassions - this was when it was around 7mins. so i would be cautious about attributing Mark's result solely to the IHT, although i'm sure it was a contributing factor to some degree.

i don't think doing negative statics is a good idea, because i think the negative pressure in your lungs is pretty severe due to the recoil of the ribcage when you relax your intercostals. (ok if you continue to contract your intercostals and abs, but you're not relaxed!) i think passive exhale statics are much better for you...
Alun said:
i don't think doing negative statics is a good idea, because i think the negative pressure in your lungs is pretty severe due to the recoil of the ribcage when you relax your intercostals. (ok if you continue to contract your intercostals and abs, but you're not relaxed!) i think passive exhale statics are much better for you...
Why is the negative pressure bad? Is it bad to have strong contractions with negative pressure?

because if the pressure differential is big enough then alveolar capillaries will burst. contractions with negative pressure... yes, really bad!
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The graphs that Richard produced were samples from a 'bad' day at the beginning of the exercise, and a 'good' day toward the end. As with many experiments, there were lots of variations inbetween. Although the sessions were well-controlled, my lifestyle over the three week period continued as per normal. So I had days where I had drunk alcohol the night before, days where I had been stressed at work or not slept well the night before, and my diet would have varied to have made changes to my blood ph levels.

Richard was keen to keep my buffering above 80%, not so much for training reasons, but for concerns about damage to health. This was probably erring on the side of caution, as we know that many of us ( such as Eric F ) can tolerate much lower percentages without any perceived bad side-effects.

The main difference between breath-holding and IHT aspiration, is that IHT is constantly removing the CO2. With breath-holding, C02 builds up to the point where you have to breathe, or where you black out. With the former, this is a safety valve that IHT does not have. This is why it is important to keep higher buffering percentages. ( This is my understanding, although I am not an expert! ).

As part of the experiment, I also used a personal hypoxicator, and this is designed to not allow lowering of O2 percentages to dangerous levels ( I don't think I managed to get it below 12% ).

All of this isn't really answering the question about how you should adjust your training, but might give an insight into how variations occur, and the relevance of the buffering percentages used in these trials.

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I agree with your comments about the PB - this could have entirely been 'the placebo effect'. The buffering graphs are a bit more evidential, even without seeing the full range. The overall trend was a definite increase in buffering ability.

I read Donmoores observations on empty lung apnea and pulse oximeters.
The oximeter results you refer to is probably wrong, they sound very strange.

Pulse oximeters with the probe on the finger is not workning properly for apnea. First there is a delay so that the oxygen level that hits the brain will hit the finger oximeter 20 seconds later, i.e. you will have no warning from that oximeter to prevent a blackout. Second the diving response cause vasoconstriction so that the blood will not circulate properly in the finger which suggests that the oxygen readings in the fingers is not representative of what your brain gets. If you want to use an oximeter during apnea, you need to use an ear lobe probe. I think that if you did 2 minutes statics on empty lungs you were probably on the edge of an LMC/BO with a true saturation of 50-60%.
Dr. Lindholm,

So glad to hear your opinions. I love to read your papers as you have probably done more research than anyone else on apnea.
if you did 2 minutes statics on empty lungs you were probably on the edge of an LMC/BO with a true saturation of 50-60%
That’s a little scary. If it weren’t for the possible damage Alum referred to, I would push it farther to see if I was in fact on the edge of LMC/BO. But from the pain associated with the contracts in the first few holds, I am afraid Alum is right that damage could be done.

The speed in which the SaO2% reading was falling after about 93% was incredible, like 1% every 1 to 3 seconds, so any time delay from vasoconstriction in the finger could have caused a large difference in true SaO2.

I would love to have an oximeter with an ear lope attachment, but the model I have is an all-in-one finger unit so adding a different probe is not possible. I better start searching E-Bay again. With normal full lung dry statics I have been down to 60% SaO2% on the finger unit 3 times and 1 resulted in a LMC.

Is the reason why Richard from The Altitude Centre was able to use a finger probe on Mark is because with IHT CO2 accumulations is less and does not cause as much vasoconstriction? I was under the opinion that a finger probe was pretty accurate down to 70% SaO2 as most of the manufactures say accuracy is +-2% from 70 – 100%. But from your message it sounds like that is with breathing and expelling CO2 and not with apnea.

Thanks for you further explanation. You got me confused now. What is the difference between IHT and a personal hypoxicator?
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Where I was referring to IHT, I really meant the treatment I underwent at The Altitude Centre. This was on a ventilator connected to a mixing unit and PC. The personal hypoxicator is a lightweight portable unit, with a rebreather and scrubber. About the size of a football.

I think Dr. Lindholm makes a good point about pulse oximeters and the diving reflex. I even wondered during the experiments if this effect was happening, as you can see on my charts that the dips are fairly rapid. Also, I experienced a frequent need to urinate throughout treatment, which suggests that blood was diverted into my core and increasing filtration through the kidneys.

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The finger probe will work very well during hypoxic breathing (IHT) because you are breathing! there will still be a delay but a delay of 20 seconds doesnt matter much when you are talking about minutes. The problem with the vasoconstricition and fingerprobes during apnea has to do with apnea and the diving response, and the delay may pose problem during exhale breath-holds because saturation changes very fast. Most pulse oximeters are calibrated and accurate down to 70-80%.

Unfortunately the manufacturers of this medical equipment does not care to much about altitude training and apnea training methods, they only want something to work in the clinical setting. Well, most doctors and nurses I have met start to get nervous when saturation drops below 90% (wich usually indicate a serious problem in a patient) so why make something that reads accurately below 90%. :)
I have an earlobe sensor for one of my oximeters (Ohmeda 3900P), and I can say that if my perfusion reading is high, then the ear lobe sensor gives almost identical results as the finger sensor, except that the finger sensor has a 25-30 second response time, while the ear lobe sensor has a 10-12 second response time. The perfusion reading is an indicator of how much blood is flowing into your fingers. Most newer oximeters have perfusion indicators.

On the other hand, if my hands are cold and/or poorly perfused, then the earlobe sensor gives more accurate results. The problem with the earlobe sensor is that it also can suffer from a low quality signal due to bad blood flow in the ear, which is why you are supposed to rub the earlobe with isopropyl alcohol beforehand. That seems to help only marginally.
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