"I tell them that what they are experiencing is a throwback to the bi-modal sleep pattern. In many historic accounts, Ekirch found that people used the time to meditate on their dreams. There was no prestige or social value associated with staying up all night.
"And then, if they turn upon their ear to take a second nap, they will be taught to look upon it as an intemperance not at all redounding to their credit. "The idea that we must sleep in a consolidated block could be damaging, he says, if it makes people who wake up at night anxious, as this anxiety can itself prohibit sleeps and is likely to seep into waking life too.Russell Foster, a professor of circadian [body clock] neuroscience at Oxford, shares this point of view. "Gartenberg says that, according to one of his Penn State colleagues, eight and a half hours should be considered "the new eight hours." If I sleep 7-8 hours, I feel good. They slept first for four hours, then woke for one or two hours before falling into a second four-hour sleep. According to Gartenberg, ideal conditions include a cool temperature (if you and your partner aren't comfortable at the same temperature it's a great idea for each of you to have your own bed covering or even a heating pad on one side of the bed); silence; and darkness, with blackout shades if your bedroom has light pouring in the window at night. You probably don't know how sleep deprived you are. Every 60-100 minutes we go through a cycle of four stages of sleepIn a full sleep cycle, a person goes through all the stages of sleep from one to four, then back down through stages three and two, before entering dream sleep"People were becoming increasingly time-conscious and sensitive to efficiency, certainly before the 19th Century," says Roger Ekirch. Many workaholics try to get through the whole day without much of a break using coffee or other stimulants, he says. You will also give yourself a better night's sleep if you use your bedroom only for sleeping and sexual activity (i.e., don't work in bed or have an office in the bedroom if you can avoid it). For most of us, eight hours of sleep a night is the holy grail of good sleep practices: Often aspired to, not always achieved.


"We weren't made to produce for eight hours straight." This started among the urban upper classes in northern Europe and over the course of the next 200 years filtered down to the rest of Western society.By the 1920s the idea of a first and second sleep had receded entirely from our social consciousness.He attributes the initial shift to improvements in street lighting, domestic lighting and a surge in coffee houses - which were sometimes open all night. Go to bed at your usual time, and then see what time you naturally wake up. If earlier the night had belonged to reprobates, now respectable people became accustomed to exploiting the hours of darkness.This trend migrated to the social sphere too, but only for those who could afford to live by candlelight. "If no disease or accident there intervene, they will need no further repose than that obtained in their first sleep, which custom will have caused to terminate by itself just at the usual hour.

If you wake up for a bit in the middle of the night, that's OK--in fact it's how our ancestors slept in the days before electric lighting was common. It’s rare, but such people are fully rested and awake during the day. If you really want to know how much sleep you should be getting he proposes a simple (and pleasant) test: Go on a vacation completely away from the distractions of work where you can sleep as late as you like. Countless prayer manuals from the late 15th Century offered special prayers for the hours in between sleeps. Ekirch found that references to the first and second sleep started to disappear during the late 17th Century. "If you're in bed for eight hours, a healthy sleeper might actually sleep for only about 7.2 hours," he explains.