Speaking as someone who has sleep apnea, my doctors have really hammered home how bad apnea events are for my general health. Does that not apply to this kind of training?
I’d guess that lack of REM would cause symptoms like daytime drowsiness, but it’s the physiological effects that are gonna kill ya.
To expand / clarify slightly: REM sleep is absolutely essential to "higher animals". It is not, though, "deep sleep" in the sense that "long slow delta wave" sleep is often called "deep sleep", and the "NREM" stages of sleep tend to be "deeper" (in the sense of physiology 'slower' / harder to awaken) than REM sleep.
This Wikipedia article could use some editing, at least for clarity, but is certainly a solid enough reference and starting point for further reading (for anyone interested): https://en.wikipedia.org/wiki/Sleep_cycle
Apnea is incredibly stressful on the body / mind. Disruption before REACHING REM sleep (one of the reasons REM may be referred to as "deep sleep" in non-technical language) is among the worst of the effects. Since most of a single cycle is NOT REM sleep but rather stages occurring before REM, REM is a phase most often prevented by episodes of apnea. But, the physiological stress also relates to disruption of other phases as well.
Besides sometimes profound effects on cognitive function varying over days and weeks depending on the severity / frequency of "apneic events", the stresses that accumulate over time tend to cause cardiovascular problems, especially.
As usual, sites like Cleveland Clinic's and Mayo Clinic's etc. give good info (short of the more technical scientific review articles you can search for on PubMed, for example). Cleveland Clinic's seems quite good to me (perhaps a bit better in clarity regarding phases of sleep than the Wikipedia article, as well):
https://my.clevelandclinic.org/health/diseases/8718-sleep-ap...
Edit: you wrote "long deep REM cycles" - that's a reasonable phrasing and would also 'frame' effects overall. So, if it's unclear from my writing (ha, write after I 'dinged' a Wikipedia article), there is no conflict (depending on exactly how one reads these messages, of course) between my message and the parent. To clarify, it was not my intention to come off that way (but I see that certain emphases might suggest that, apologies if it reads that way to some!)
That made a huge difference expanding my lung capacity, and I still have most of that expanded lung capacity today.
Seems hard to say anything substantive about the conclusions when the inputs are that shaky.
"Effects of sleep deprivation and 4-7-8 breathing control on heart rate variability, blood pressure, blood glucose, and endothelial function in healthy young adults" (2022) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9277512/ https://scholar.google.com/scholar?hl=en&as_sdt=0%2C47&q=Eff...
Pranayama: https://en.wikipedia.org/wiki/Pranayama
1. https://www.pacificcollege.edu/news/blog/2020/03/26/the-link... 2. https://pubmed.ncbi.nlm.nih.gov/17324641/
Watching my resting dog breathe I noticed he inhaled slowly and exhaled without much apparent control, just relaxing and letting it all huff out, then pausing awhile before the next inhalation; I tried this, it feels good, so I keep doing it when I want to feel more calm.
From reading Breath, by James Nestor, I learned that a good target for calm-inducing breathing is about eleven seconds for an inhale/exhale pair, common with many religious activities like chants, etc. Breathing like my dog, I aim for five seconds in, ~three out (not counting, just letting it out), and as long a pause as feels right, sometimes pushing myself a little to extend.
However you’re right to presume that small studies are likely to be lower quality, often because they’r observational as opposed to randomized studies.
If you can't show that a breathing exercise is better than e.g. same time spent on stretching, then there's not much point in doing (separate) breathing exercises at all.
Right at the end of the abstract:
> Overall, results showed that breathwork may be effective for improving stress and mental health. However, we urge caution and advocate for nuanced research approaches with low risk-of-bias study designs to avoid a miscalibration between hype and evidence.
It's interesting to think about the information conveyed by this sentence.
Would anyone seriously propose non-nuanced research approach with high risk of bias that easily confuses hype for evidence?
As in the abstract here, often the signal comes just as much from the fact that something needs to be said at all - not just the content of what is said
It's about reading the full discussion section to understand it in nuance, see the caveats etc.
It's not about a summary -- it's about skipping the intro that reviews the literature you already know, the method, all the tables of results, and jumping to the actual good stuff.
I frequently find myself scrolling to get to that part, overshooting, scrolling back...
So after searching through 1325 papers and systematically summarizing 12 randomized controlled trials, this is the result? This has kept multiple professors busy for months and all we learned is "breathwork may be effective"?
It doesn't matter anyway. The professors have a Nature publication and Nature has some readers. Everybody happy.
The message is that the effect has (may have) been proven since "showing breathwork was associated with lower levels of stress than control conditions".
