Does this help? I am a physicist with interest in these subjects and have always been wary of breathwork because of tetany and the following studies. What do experts closer to this field make of these?
Ref. [2] is especially concerning to me in pushing in any sort of static apnea training or breathwork: "The time to complete the interference card test was positively correlated with maximal static apnea duration (r = 0.73, p < 0.05) and the number of years of breath-hold diving training (r = 0.79, p < 0.001)."
So the tetany in breathwork is generally caused by the decreased CO2 concentration causing respiratory alkalosis (ie blood gets more alkaline and has a ph balance of > 7.5), which in turn causes the protein albumin to bind more strongly to calcium and not release it as it's supposed to, and calcium is an important regulator in voltage gated ion channels in neurons.
Long story short, your neurons get just a tad bit more excitable because calcium that usually acts like the bouncer to the hot club is busy snogging albumin. That has very little effect in places in the body, but in motor neurons that control your smallest muscles (face and hand), and in sensory neurons under your skin it does move the needle — that causes the muscles to contract and your skin to feel tingly, both exactly the same cause.
This is the reason people with epilepsy should _NOT_ do breathwork, but for otherwise healthy adults there are no negative long term effects of respiratory alkalosis — a few normal breaths to balance out your co2 and the symptoms will go away.
Could you please explain more about the Ref[2], what does it mean beyond what is in article and how serious is it?
"These findings suggest that breath-hold diving training over several years may cause mild, but persistent, short-term memory impairments"
Can you tell more about recreational nitrous oxide and when does the "damage occur"?
Is there the same thing with wim hof?
(like for example with oximeter 80 Sp02 or below?)
I got in wimhof/oxide around 80 Sp02 the interesting thing is I got this feeling with fighting to hold my breath but below 90 I kinda needed to convince myself that I should breath in both cases,
Being a non-expert I can't attempt to speculate on your questions in good faith! All I was suggesting to the parent is that perhaps these articles offer as evidence of damage being done without pushing to the point of unconsciousness? Feedback is definitely welcome by an expert.
In a medical setting, where I am more familiar with it, tetany is never good. Personally it is also wildly uncomfortable. Perhaps it's fine and somehow pushing through it is part of the "experience", but if I want an altered consciousness I'll stick to a psilocybin-based retreat every 5-10 years and my meditation practice in between :D.
This sounds great but I just can't get by the oxygen deprivation and potential harm to your brain. Not to mention the hypercapnia induced tetany is very uncomfortable and seems a clear signal from the body that "this isn't good!".
[As part of a psychedelic retreat we did breathwork the day before the trip to "open the mind". I faked it because I was worried about the above unanswered questions I had. I still had a great trip and feel no need for another one or similar (ie. via breathwork) to this day. :) ]
In response to this there is vasoconstriction of the cerebral vasculature. No one knows if mild damage is being done to the brain from this.
Somewhat related (not exact same mechanism, but similar), there is evidence elite free-divers are harming their brains [1]. It is easy enough to find literature about the appearance of SB100 protein with too long apnea training (eg. [2]).
However, breath-holding/apnea is not the same as breathwork. The fact of the matter is, there will be no definitive proof one way or the other until someone directly probes cerebral O2 levels for an acute and chronic intervention of breathwork. Again, as someone who has indeed done psychedelics and meditates, I am open to alternative modalities, but I will personally wait for the science over anecdotes.
At least I appreciate they have the decency to not call it "higher states of consciousness". Altered is what they are, altered almost to the point of losing it, but definitely not higher - at least for my understanding where "higher" would mean some added capabilities not attained otherwise.
I think I recall reading a paper a while back on free divers that showed there was damage being done to the brain even though it wasn't immediately apparent. Similar to how lots of small brain impacts add up in football players.
I'm almost certain any amount of oxygen deprivation is damaging to the brain. If there were studies that showed conclusions to the contrary, I'd be very curious to read them.
Edit: Sorry, missed your point on first reading, which perhaps reinforces your point. I read papers like this for a living so the language is unambiguous but I see how it might not be for others, even if English is their first language.
My greatest "productivity" improvement over the years is exactly this. Learning how to tell others (and myself) diplomatically "no". I used to take on, and create for myself, endless projects to "work on" and felt like I never accomplished anything. Paring down to the most important and fulfilling projects (and not trying to be everything to everybody) has improved things significantly.
I noticed myself doing this more and more, but not in the context of personal productivity, but rather in the context of "how can I help you help yourself". The gist is usually "can we solve this in some way that doesn't involve me coding a full blown technical solution". A lot of times, a workable solution is as simple as "just write 2 paragraphs about it in the docs" (and then mindlessly copying+pasting the link to it in chat until people get the message to just go RTFM). Or spending an hour doing a brain dump of the problem/solution space and letting them go off and do the work themselves.
I have Starlink and am in a wooded part of New England. I mostly agree with freedomben's points. All I will add is I still use my cell phone hotspot (Verizon -- only carrier that gets a modicum of service where I am) for Zoom calls or similar. Starlink is definitely fast but too many hiccups for video calls.
Edit: More musings. There is a push to get broadband in our area within the year. If that happens and Starlink's service remains the same, I will cancel Starlink. For me continuous connectivity is much^3 more important than speed.
"Rural" and East Coast is basically the metropolis some other areas of the world. Not surprising you'll have something better than Starlink sooner or later. Lots of other places? Not gonna happen.
I never claimed I was in a "rural" area, just a "wooded" one. Indeed, Starlink will be a great option for many places. I personally hope they improve the coverage with more satellites so I can continue using it.
[1] "Brain Damage in Commercial Breath-Hold Divers" https://journals.plos.org/plosone/article?id=10.1371/journal...
[2] "Do elite breath-hold divers suffer from mild short-term memory impairments?" https://cdnsciencepub.com/doi/10.1139/apnm-2017-0245
Ref. [2] is especially concerning to me in pushing in any sort of static apnea training or breathwork: "The time to complete the interference card test was positively correlated with maximal static apnea duration (r = 0.73, p < 0.05) and the number of years of breath-hold diving training (r = 0.79, p < 0.001)."