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IHT - Blood results after 20 days

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Well-Known Member
Jan 21, 2004
Hi DBers,

Some of you may be interested in my blood results after 20 days on the DIY hypoxicator. I completed 20 days of 1.5 hours a day. The 1.5 hours was @ 8%-10% FO2 and was made up of 5mins "on" / 5 mins normoxic repeats.

Here are the results

Item Before --> After
Haemoglobin 152 --> 154
RCC 5.26 --> 5.28
Haematocrit 0.465 --> 0.469
MCV 88.4 --> 88.8
MCH 28.9 --> 29.4
MCHC 327 --> 330
RDW 13.5 --> 12.7
White Cells 6.5 --> 7.5
Neutrophils 3.8 --> 4.4
Lymphocytes 2.0 --> 2.5
Monocytes 0.5 --> 0.4
Eosinophils 0.1 --> 0.1
Basophils 0.1 --> 0.1
Platelets 217 --> 208

Any comments/analysis on the numbers above would be appreciated


i think there's a good chance your Hb/HCT would vary more than that during the course of the day as your level of hydration fluctuates. you'd need a very accurate measurement (and lots of them) to detect a change that small with any confidence. i think the error on the Hemocue, for example, is +/- 3g/l.

there seems to be a significant increase in white cells though... would that be an effect of hard training??

Did you try the same thing with and without exercise? Mine was done sitting on the couch in front of the TV. Seb suggested that the body may need to be under more stress than this to prompt any real adaptations and that a stationary bike or treadmill might be worth trying.

Alun - I was training hard those weeks but no more so than usual.

I'm not sure all the huffing and puffing and 5am mornings was really worth it! !

One of the shortcomings of simulated high altitude studies, unlike actual high altitude exposure is that they are often done under sedentary and normothermic conditions. High altitude climbing, not unlike apnea diving, is often associated with two important additional stressors: conditions of extreme cold and work. That probably makes all the difference.

AS you mentioned Alun, there are no significant diffs. with this protocol but Andy could be low/non-responder.

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Maybe the blood readings are not the sole indication of benefit from your training. The guy who conducted the study on Mark H. from U.K. wrote that not everyone increases hematocrit. But they still show signs of improvement in buffering hypoxic states and subsequent recovery. He hypothesized that some people have adaptations (other than production of increased hermatocrit) that would not show up on a blood test.

The real question is have you seen any improvement in static, dynamic, constant weight as a result of your training.
Hi Michael,
It's hard to tell......I definitely went backwards during the 20 days. I haven't noticed any real performance improvements post, but that could be for any number of reasons relating to other variables, such as working long hours, home renos taking up training time, recovering from 20 days of 5am starts to do the IHT sessions etc. It is next to impossible to tell the IHT impact given all these variables. All things considered, I was getting some real improvements to dynamics & statics doing daily no warmup/no breathup training and I stopped doing this to do the IHT sessions which seems to have resulted in a "de-training" effect. In hindsight, it was interesting to go through the experiment and fun to build the system but I wish I had put the 20days (30hours) into no warmup no breathe up training.

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I noticed that hyperventilating a lot for several weeks makes it harder and harder to cope with contractions. I came to this conclusion after doing the alternative for a hypoxicator (see post TYLERZ) and hearing about the apnea results of ADR.

The hypoxicator ADR made is also take up all the CO2, so training 20 days hypoxic this way is also adapting your body to hypocapnia(too low CO2). Wouldn't it be better to make a simple pendulum hypoxicator (=rebreather) with some dead space to accumulate a little CO2, cause that is what you do while holding your breath, isn't it???

Any comments???
Interesting observation. If 'hyperventilating' means deep and fast breathing, it always made it easier to deal with contractions for me and made them come later. I never did it for several weeks though.
Andy's results seem minimal except for the heartrate.
As for CO2, can the body sense the CO2 in the lungs? Doesn't high CO2 make O2 utilization easier? Do we want to make the training easier?
No question that the body will adapt to low PPO2 at rest, the real question is will 20 hours of hypoxicating do more for a free diver than 20 hours of using the CO2 and O2 tables or just doing a max breath hold every day for that matter.
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