Sleep

[BenTC]

Even though I don't have the freedom to try it our at the moment, I have taken a bit of it on board. When I get tired, I lay down with my alarm for 25 minutes. I find it does refresh me, and sleeping longer doesn't. Sometimes I don't sleep, but pretending to for that period of time still helps.

The current project I'm on is a 40 minute trip each way through the countryside. We car pool and I drive in the morning, and in the afternoon take the backseat zonk out and wake naturally about half way through the trip. So I guess I'm actually sleeping byphasic at the moment. I really does help my energy in the evenings.

[BenTC]

Human free running internal clock is about 28 hours.

2*(10+4)=28

That also works for polyphasic sleep.
7*(3.5+0.5)=28

[Betruger]

The only study I've seen is Claudio Stampi's. I can send a copy to those curious to read it. The abstract is here..
http://www.informaworld.com/smpp/conten ... 473~db=all

In situations where continuous prolonged work demands exist, the habitual nocturnal monophasic (6-8h duration) sleep pattern can rarely be accomplished, and performance effectiveness may sometimes be severely compromised by accumulation of sleep debt. Several studies have shown that naps can be disproportionately effective in recovering functioning during continuous work (CW).

In this study, sleep-wake patterns and their relationship to performance were studied for 99 sailors involved in solo and double-handed ocean sailing races (a model of a highly demanding CW situation). Most sailors spontaneously adopted multiple nap sleep-wake schedules and adapted without major difficulties to such polyphasic patterns. 66.5% had mean sleep episode durations (SEDs) ranging from 20 min to 2h. Overall mean Total Sleep Time (TST) per 24h was reduced from a baseline of 7.5 to 6.3h. Race performance correlated negatively and significantly with mean SEDs and TSTs. Best performance results were obtained by those sleeping for periods of between 20 min and 1 h and for a total of 4.5 to 5.5h of sleep per day.

The results are discussed together with several chronobiological, phylogenetic and experimental studies and issues, all of which suggest that adult humans may have a damped polyphasic sleep-wake tendency. It is also proposed that polyphasic sleep schedules could become promising and feasible solutions for the management of sleep requirements under prolonged CW situations.

Amazon.ca has a copy of his book
http://www.amazon.ca/Why-Nap-Chronobiol ... 0817634622

[TallDave]

I worry a lot about falling into irregular sleep cycles. Lack of sleep increases the incidence of so many chronic diseases.

I try hard to get 7 in every 24. If I didn't worry about it, I'd probably go 36 - 48 hours without sleeping on a regular basis.

Melatonin is helpful, and fun too.

I have been keeping schedules like I posted above and my health is fine (for an old man).

I don't lack sleep - when I'm tired I sleep and when I wake up I'm awake. What I lack is regular cycles.

Of course, everyone is dfifferent so if you don't feel tired odds are good you're probably OK. My problem is my neocortex overrides my hindbrain too easily in some regards. I can easily go long periods without eating or sleeping if I'm fixated on something.

OTOH beware of small sample sizes (i.e. "I feel okay"). 7 in every 24 is a good general rule if you want to be extra-careful. As we get older, we tend not to get enough, and ever since we figured out how to make light with fire at night we've been melatonin-deficient as a species.

Some interesting reading at the banal oracle: http://en.wikipedia.org/wiki/Sleep

I found this line of reasoning especially intriguing:

Energy conservation could as well have been accomplished by resting quiescent without shutting off the organism from the environment, potentially a dangerous situation. A sedentary nonsleeping animal is more likely to survive predators, while still preserving energy. Sleep, therefore, seems to serve another purpose, or other purposes, than simply conserving energy; for example, hibernating animals waking up from hibernation go into rebound sleep because of lack of sleep during the hibernation period. They are definitely well-rested and are conserving energy during hibernation, but need sleep for something else.[36] Rats kept awake indefinitely develop skin lesions, hyperphagia, loss of body mass, hypothermia, and eventually, septicemia and death.[37]