The medieval habit of 'two sleeps' (2022) • Hacker News Board

Re: The medieval habit of 'two sleeps' (2022)

#81

Post by INTPenis » Fri, Feb 02, 2024, 10:01 PM UTC

q7xvh97o2pDhNrh wrote: post #76

INTPenis wrote: post #32

Ever since I learned of sleep cycles, and how to measure my own, I've pretty much governed my life around them. Each person has a cycle where they go between waking and resting state. The trick is to go to bed when you're headed into resting state. And if you wake up and can't go back to sleep, get up and do something for X number of minutes until you go back into resting state. For me the cycle is about 45-50 minute…

Can you share more about how you got accurate measurements on this? I've got some moderately interesting graphs from my fitness tracker, and I'm broadly aware that my sleep cycle is not the "usual" 90 minutes that the standard-issue human gets. But I've had a lot of trouble refining the data to a useful point, let alone building a routine around it.

I did this at community college ~15 years ago. So I'm mostly improvising regarding my cycle being that long. I'd say it's around 60 minutes.

Specifics don't matter after a while because you build new habits and do them without thinking.

But the thing our teacher told us was to stay up until you get more and more tired, until you feel your eyelids wanting to close, but power through it and measure the time between the most tired and the most alert after that.

Re: The medieval habit of 'two sleeps' (2022)

#82

Post by ianburrell » Fri, Feb 02, 2024, 10:38 PM UTC

Cthulhu_ wrote: post #73

lmm wrote: post #3

Has this evidence been examined sceptically? I've heard this theory a few times, but it always sounds like one person's obsession, and I struggle to credit it.

Anecdotal / from memory, they did a study (at least) once where people didn't have artificial light (not sure if they had candles or nothing at all), and found that people naturally went to sleep when it went dark - not much else to do - but also woke up after a few hours. But I'm not entirely sure; how much can you do awake if it's dark? But then, it's rare for it to be truly dark, with moonlight and the like.

I wonder if this changed with the seasons. In the winter, the night is longer than normal sleep amount and might make sense putting extra time in the middle of night. In the summer, the night is shorter and would sleep through.

Re: The medieval habit of 'two sleeps' (2022)

#83

Post by CalRobert » Sun, Feb 04, 2024, 2:33 PM UTC

clarkema wrote: post #65

CalRobert wrote: post #53

Earlier quoted context omitted.

I never found a solution. I ended up using a very red-shifted screen set to a very low light but what I really wanted was e-ink, like a Kindle for instance. The only options I came across were impractically expensive, though. https://shop.dasung.com/products/dasung-25-3-e-ink-monitor-p... for instance, and this was years ago when there were fewer options.

I have a 'study' setup using a Boox Mira (portable 13" eink screen) for exactly this kind of use; not polyphasic in my particular case but late evening use. Yes, the screen is expensive, but _totally_ worth it.

Thanks for the tip!