Blood oxygen concentration during Wim Hof breathing

 Here is some interesting data:  Blood oxygen concentration and heart rate during three cycles of Wim Hof hyperventilation and breath holding.

Total elapsed time 14 minutes.  3rd breath hold I went two minutes and bottomed out the blood O2 meter!

Method: 

Followed "Guided Wim Hof Method Breathing" video on Youtube.  

Used Wellue O2 Ring Blood Oxygen Monitor to measure blood oxygen. I tested several wrist spO2 monitors and this finger spO2 monitor is much faster and more accurate. 

HRV "Resonant Frequency" Test

HRV is often used to assess relaxation and recovery, but it is not clear if it correlates with R&R, or somehow causes it.  I think the claim is that it causes it, because HRV is supposed to directly reflect autonomic activity, with higher values indicative of more balanced sympathetic and parasympathetic activity.  (But some recovery scores are calibrated to not let the score get too high all at once.)

But HRV is very susceptible to intentional breathing frequency.  This can be good or bad, depending on whether this manipulation is considered functional or just gaming the system.  

HR naturally slows on the exhale, and speeds up on the inhale, reflecting the dominance of parasympathetic and sympathetic systems, respectively.  By adjusting the frequency of breathing to be resonant with some natural rhythm, HRV can be increased optimally.

I tried breathing rates from 4.5 to 6.5 breaths/minute (at 0.5/bpm steps) and found 5 breaths/minute (=6 seconds in, 6 seconds out) to be optimal for increasing my HRV.  This is my personal optimized meditation breathing frequency for reducing stress.  

HRV is greatest when I take belly and chest breath deep in, then really relax completely on breath out.

Loren Eiseley on Archaeology

"Archaeologists, during the course of their lives, see and hear may strange things, but the fact that they are scientific men keeps them for the most part silent.  They have good, if not superior, rationalizations for the things they do.  No layman would dare impugn their motives.  I, for example, have a certain number of skulls in my possession  As I write I can see four on the shelf above me.  At least two are hidden in my filing cabinet, and there is a beautiful fragment on my desk which is often fondled by visitors who are unaware of its human significance.

Now as it happens I am fortunate.  I practice a trade which enables me to keep these objects about in a perfectly logical and open manner.  I have not murdered to possess them, and if one or two were acquired in dark and musty places, my motives, as I have hinted, are beyond reproach.  As an archaeologist I can be both a good citizen and a frequenter of graveyards."

Human remains and the associated objects reminds me of another passage:

"It struck me that every ruined civilization is, in a sense, the mark of men trying to be human, trying to transcend themselves….none of them has quite made it, but they have each left artifacts. 

The archaeologist, it is said, is a student of the artifact.  That harsh, unlovely word, as sharply angled as a fist ax or a brick, denudes us of human sympathy.  In the eye of the public we loom, I suppose, as slightly befuddled graybeards scavenging in grave heaps.  We caw like crows over a bit of jade or a broken potsherd: we are eternally associated in the public mind with sharp-edged flints and broken statues.  The utter uselessness of the past is somehow magnificently incorporated into our activities. 

No one, I suppose, would believe that an archaeologist is a man who knows where last year’s lace valentines have gone, or that from the surface of rubbish heaps the thin and ghostly essence of things humans keeps rising through the centuries until the plaintive murmur of dead men and women may take precedence at times over the living voice.  A man who has once looked with the archaeological eye will never see quite normally.  He will be wounded by what other men call trifles.  It is possible to refine the sense of time until an old shoe in the bunch grass or a pile of nineteenth-century beer bottles in an abandoned mining town tolls in one’s head like a hall clock.  This is the price one pays for learning to read time from surfaces other than an illuminated dial.  It is the melancholy secret of the artifact, the humanly touched thing."

Quotations are from The Night Country, by Loren Eiseley