[TeMPOraL]

Same here. It seems that I don't have just one tank for "energy", but two, and the second one unlocks somewhen between 20:00 and 23:00. More than that, no matter what time I go to sleep, I can't possibly get up on my own before ~10:00. This does not happen, period.

Between moving out of my parents' house and moving in with my wife, I had some years to do experiments on this, and there's one consistent result: whenever I'm not forced to wake up at specific time (say, by threat of getting fired, or just because I asked someone to keep calling me to make sure I got up), my sleeping pattern always settles around going to bed ~04:00 and waking up ~11:00. Whenever the external pressure stops, I automatically revert to that mode in two or three days.

It would all be fine, except this sleep mode is thoroughly incompatible with normal people and the society at large :/.

[kennyadam]

I'm very similar to you. Left to my own schedule, I will go to bed around 2-3am and wake up about 10am. Unfortunately, I have to be out of bed around 6:30am for work, but no matter how hard I try or how tired I was during the day, when it's the evening my brain wakes up and I just cant get to sleep before 12-1am. The only thing that really helps is cannabis, but as I got older cannabis started giving me anxiety really bad.

[nicolas_t]

I've been able to make this sleeping pattern work by being in Asia while working with American companies. I reserve 11pm to 3am for meetings/sync with other employees, I work from home and do any work that requires deep concentration in the late afternoon and I reserve lunch plus early afternoon to play with my son.

Luckily my partner is also a night owl and if she weren't forced to wake up early for work would go to sleep around 2-3am. So, when we're on holiday, we're in sync.

[6510]

It would be cool to research those ideal times. It is obvious that if one sticks to the hard coded ideal rest/wake times one is much more energetic, productive and more focused but I'm curious how big the difference is. Around 11 am I can wake up and cycle 200 km or run a marathon starting immediately. If you ask me kindly to run 100 meters around 6 am your life is probably in danger.

[inciampati]

That second tank is caused by light at night.

In my opinion, most people who say they are night owls are just light sensitive.

If we didn't have so much light in our environment at night we would be bored to sleep. On top of this, there is also a physiological effect from light. It suppresses melatonin and makes you feel newly awake to be in anything above the intensity of candlelight.

Of course there are social elements to staying up late and partying. But unless you are a party animal (and it's great if you are, the world needs more happy socialization) it's hard to believe that this causes you to stay up late every night.

[TeMPOraL]

> That second tank is caused by light at night.

I don't know. If anything, maybe not total light, but some kind of inside/outside delta?

I am light sensitive. I tolerate only two states: very dark and very bright. The average underlit indoors people keep during the day, when there's not that much sunlight coming in, but enough for them to keep the lights off - those shut me down very quickly.

I normally thought of it in terms of not enough light, but I just realized it's not exactly it. There are cases when, during the day, the total of sunlight + artificial light in the room is squarely in the underlit, sleep-inducing zone, but only few hours later, once it's dark outside, the same amount of artificial light is enough for my mind to consider the room bright enough.

Still, the "second tank" effect doesn't feel light-related. It's fast-acting - one moment I'm tired out of my mind, the next one I realize someone just plugged me up to a fresh battery - and the change occurs without any obvious prompt like changing locations or light levels.

As for social element, I'm not a party animal. But I am someone who suffers from something like 報復性熬夜 - "revenge bedtime procrastination". The late-night ours, after everyone around me is asleep and couldn't possibly bother me anymore, are the only time I feel I can finally unwind, relax, and recover. I've had this for a long time, but I'm fairly certain it's a downstream effect - that is, my difficulty getting up and extra energy kicking it after dark were something I've had for much, much longer.

[imarg]

I liked this phrase "revenge bedtime procrastination". In my case there is often this parameter that I do not want the day to end, I feel I did not accomplish enough during the day or that I did not have enough "me" time and I spend the nights in front of my PC or watching a movie/series.