“Core sleep” is a variant of Uberman that adds a block of sleep, usually several hours, to the Uberman schedule, replacing one or two naps. (This term is also sometimes used to describe accidental oversleep by someone following Uberman, though one will more likely see the term “crash”, and occasionally “reboot”.) Another variant is called Everyman sleep schedule.
Buckminster Fuller advocated Dymaxion Sleep a regimen consisting of 30 minute naps every six hours. A short article was published about this schedule in the October 11, 1943 issue of Time Magazine. According to this article, he followed this schedule for two years, but after that had to quit because “his schedule conflicted with that of his business associates, who insisted on sleeping like other men.”
Scientists say that a successful midday nap depends on two things: timing and (no kidding) caffeine consumption. Experiments performed at Loughborough University in the UK showed that the sleep-deprived need only a cup of coffee and 15 minutes of shut-eye to feel amazingly refreshed.
1. Right before you crash, down a cup of java. The caffeine has to travel through your gastro-intestinal tract, giving you time to nap before it kicks in.
2. Close your eyes and relax. Even if you only doze, you’ll get what’s known as effective microsleep, or momentary lapses of wakefulness.
3. Limit your nap to 15 minutes. A half hour can lead to sleep inertia, or the spinning down of the brain’s prefrontal cortex, which handles functions like judgment. This gray matter can take 30 minutes to reboot.
more here. i need my sleep more than anything else.