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Ben Franklin's quote:
Achieve-IT! December 18, 2005 How to Take A Caffeine Nap Sleep researchers at the Loughborough University in Britain did several tests on fatigued drivers to compare the effects of different methods for a driver can use to stay awake. They put the volunteers in driving simulators while they were sleepy and let them drive. Some of the tests included rolling down windows for cold exposure, blasting the radio and slapping oneself in the face to try to stay awake. But what researchers found worked the best was a Caffeine Nap. The Caffeine Nap is simple. You drink a cup of coffee and immediately take a 15 minute nap. Researchers found coffee helps clear your system of adenosine, a chemical which makes you sleepy. So in testing, the combination of a cup of coffee with an immediate nap chaser provided the most alertness for the longest period of time. The recommendation was to nap only 15 minutes, no more or less and you must sleep immediately after the coffee. Considering this is something cheap and accessible to virtually anyone it's probably a good tip to keep in your toolbag for long trips.
'How much Sleep do we need ?'
However, researchers in America tend to take a different view. They assert that because most of us can extend our daily sleep, we must need to do so. This would mean that people who seem content with seven and a half hours of sleep a day during the week but enjoy nine hours at the weekend are, unknowingly, chronically deprived, and actually need nine hours every day. Evidence for this is said to come from the many people who are sleepy in the daytime, and the numerous reports of people fallings asleep at work and, worse, while driving. However, this has little to do with requiring nine hours of daily sleep. Most of these tired people sleep for fewer than six hours because they are shift workers, or combine long work hours with running a home, or simply because they are socialising at night or watching too much late-night television. Many of the driving accidents caused by people falling asleep at the wheel happen in the early morning, throught drivers having had little or no sleep at all. Sleeping for nine or more hours a night is not necessarily beneficial to health. recent surveys in America have shown that adults who are either long or short sleepers tend to die younger. The reasons are unclear and could be due to underlying illnesses unrelated to sleep. For example, many people permanently sleeping fewer than six hours daily are more likely to be heavy smokers, have high-fat and low-fibre diets, drink more alcohol, do little exercise and generally disregard their health. They might also be more stressed and desire more sleep. Claims that our great-grandparents slept longer are largely based on speculation. A renowned study in 1910, by Drs Terman and Hocking of Stanford University, California, compared the sleeping habits of 2692 Americans with findings from England and Germany. Age for age, Americans seemed to sleep up to one and a half hours longer per day. The investigators' attributed what they called 'this astonishing difference' to Americans sleeping longer because they spent more time outdoors, were wealthier and had a 'superior home environment.' The Victorians regarded sleep as an indulgence to be frowned upon. Sleeping beyond eight hours a night was thought to indicate idleness or an all-too-adequate private income. Some 50 years earlier, Napoleon Bonaparte, who was not a good sleeper, had advocated 'six hours sleep for a man, seven for a woman and eight for a fool,' reflecting the common view that around seven hours was adequate. There could be a grain of truth in this. At the Sleep Research Laboratory at Loughborough University, our recent study involving 400 men and women, aged 20 to 70 years, sleeping at home, found that women generally slept an average of seven-and-a-half hours daily, about 15 minutes longer than men. We also found that older people slept about 45 minutes less at night than did young adults. These sleep periods may seem rather short, but they exclud the times taken to drift off at night and wake up in the morning. Of course, sleep length is not all that matters, as the best sleep is uninterrupted. Six hours of this are far more refreshing than, for example, 10 hours of disturbed sleep. Many people lose out on sleep during the working week, having less than six hours a night; they then make up for it at weekends. However, only about a third of this lost sleep needs to be regained, and it does not have to be recovered hour for hour. Much of the weekend sleep-in is not necessarily for recovery, but for enjoyment; even those people who have enough sleep during the week will indulge in a Sunday morning lie-in. Supporters of the theory that we are chronically deprived of sleep claim that several nights of nine-hour sleeps will make us feel better, but there is little evidence of this. At Loughborough, we have studied people who extend their sleep for many nights, remaining in bed for 10 hours after lights-out and sleeping for as long as they wanted. They gained little and discovered distinct disadvantages - it took them longer to fall asleep, they woke up more during the night and found getting up in the morning to be no easier. Humans are designed for two sleeps a day - the main one at night and a nap in the afternoon - which explains why people in the warmer parts of the world have an afternoon siestaa, and why the rest of us are likely to be sleepy at this time. People who increase their night-time sleep find that this afternoon 'dip' disappears. However, a 10-minute nap at lunchtime is just as effective. Surprisingly, while insomniacs usually want more sleep, they tend not to complain of excessive sleepiness in the daytime. Often, daytime sleepiness is not due to sleep loss, but is the tiredness of mild depression; other symptoms of this include a general loss of interest, lassitude, difficulty in getting going and feeling miserable. This is why treating insomnia in isolation may not be successful. Instead, sort out these other problems and the insomnia may well disappear by itself. For severely depressed patients, sleep restrictions can be therapeutic. Cutting back on sleep to fewer than four hours for one night often results in a dramatic improvement of mood, with the depression lifting rapidly, albeit leaving the patient sleepy. Unfortunately, this remarlable effect lasts only for as long as the patient continues to remain awake, as the ensuing sleep usually leads to the return of the depression. Sleep and mood are interlinked in intriguing ways that are still not understood. But a satisfying sleep, like a satisfying meal, can leave on happy and content, without feeling too full, and with room, perhaps, for just a little more.
Peppermint, cinnamon pep up drivers
Read Don Arthur's work on Fatique
Outside Magazine, April 2005 Page: 1
2 3 4 Correspondent TIM ZIMMERMANN is the editor of the adventure blog The Wetass Chronicles (www.wetasschronicles.com). o Subscribe to Outside magazine for
just $1.50 per month. Out There
By Tim Zimmermann Since the Transat's start, a week earlier, Harris had been subsisting on three to four hours of sleep a day, snatched mostly in 20-minute naps. But when he found himself in perfect sprinting conditions, with his first real chance to tear into the 100-mile gap between Now he was faced with protecting a slim lead just as his brain and body were screaming for sleep. Harris fought to keep the boat moving as light winds settled over his stretch of the sea, but his coordination deteriorated into five-martini territory, and he started to pass out on his feet, crashing repeatedly to the deck. Finally, he surrendered and slept for two and a half hours while Wells Fargo went nowhere. When he awoke, the position report delivered the cruel news: Stone was back in the lead. "I knew I had shot my bolt," Harris said. "I pushed myself past my limits." MANAGING SLEEP deprivation is a critical skill in the solo-sailing racing game, and Harris-who finished second to Stone after another week of difficult conditions-knew he was risking a meltdown with his mad dash for the lead. Four months before the Transat, he had been to see Dr. Claudio Stampi, the 51-year-old sole proprietor of the Newton, Massachusetts-based Chronobiology Research Institute, which he founded in 1997 and which is dedicated to the highly refined art of achieving maximum performance on minimal sleep. Stampi, whom sailors often refer to as Dr. Sleep, is the go-to guru when you want to race sailboats alone across the ocean on ridiculously small amounts of shut-eye. Stampi had become interested in chronobiology-the study of biological rhythms-as a young student at Italy's University of Bologna, from which he received a medical degree in 1977, a Ph.D. in biomedical engineering in 1983, and a degree in neurology the following year. He has been obsessed with the trade-off between sleep and human performance ever since, publishing more than 100 research papers on the topic and, in 1992, a book, called Why We Nap. Over the years, Stampi has attracted a diverse clientele, from NASA astronauts and long-haul truckers to jet-lagged CEOs. But his specialty is helping sleep-deprived solo sailors. "Solo sailing is one of the best models of 24/7 activity, and brains and muscles are required," Stampi said one day at his home, from which he runs the institute. "If you sleep too much, you don't win. If you don't sleep enough, you break." Stampi has been hanging around docks for the past 20 years, placing custom-designed sleep-tracking wrist monitors (which record movement over time) on more than 100 solo sailors. His untraditional research raised questions from scientific sticklers, but according to James Maas, a professor of psychology at Cornell University and a leading specialist in sleep deprivation and performance, Stampi's open-ocean work has been very useful. "People often wonder how these guys, or someone like Charles Lindbergh, do what they do," Maas says. "So any evidence we can get as to how people will react under extreme conditions on very little sleep adds tremendously to our understanding." The extensive data Stampi obtained from the monitors led him to an interesting conclusion: Sleep-deprived humans are better off snoozing like most animals-in brief, precisely timed naps. "For those sailors who are seriously competing, Stampi is a necessity," says Brad Van Liew, a 37-year-old Californian who began working with Stampi in 1998 and went on to become America's most accomplished solo racer and the winner in his class of the 2002-2003 Around Alone, a 28,000-mile global solo race. "You have to sleep efficiently, or it's like having a bad set of sails or a boat bottom that isn't prepared properly." Stampi also helped 28-year-old British sailing superstar Ellen MacArthur to become the first woman to win the Transat, in 2000, and she went on to knock off a singlehanded global circumnavigation, on February 7 of this year, in 71 days and 14 hours, smashing the former record by 32 hours. "The more time you can be awake and alert, the faster the boat is going to be sailing," says British sailor Mike Golding, one of the world's best soloists and winner of the 60-foot monohull class in the Transat 2004. "By working with Claudio, I've been able to cut my average amount of sleep from 5.5 hours to 4.5." So when Joe Harris decided to join the somnambulistic solo-racing fraternity, he made a point of immersing himself in the teachings of Dr. Sleep, who helped Harris learn to nap according to his body's needs. I decided to do the same, albeit for different reasons. I'm an amateur sailor and a new father battling the awesome sleep-sapping powers of the human infant, so I visited Stampi hoping to crack the code on how to perform better with fewer hours in the sack. STAMPI IS SLENDER and has an easygoing international charm; he was born to Italian parents in So Paulo, Brazil, where his love of sailing began at age three. Striking photos from his many adventures at sea, which include two round-the-world races, are all over his house, as are vestiges of the boats he has loved-including sections of a broken mast and a cabin door that he uses as his work table. After a childhood spent messing around on boats, he moved to Italy as a teenager and went on to receive his medical degree. "I had conflicting desires in life," Stampi says, "but as soon as I encountered chronobiology, I knew I could find a way to merge the sacred-medicine-and the profane, sailing." That meant entering the first round-the-world sailboat event he could find-the 1975 Clipper Race, from the United Kingdom to Australia and then on around Cape Horn and back to the start-to do some onboard research. Stampi monitored the sleep patterns, body temperatures, and cognitive performance of his six crewmates every two hours. He turned the resulting data into his dissertation. The benefits of frequent naps made sense to the sailor in Stampi, who understood the demands of a boat. But he had no scientific proof that, in situations of sleep deprivation, polyphasic sleep-the term for frequent napping-was more efficient than monophasic (getting sleep all in one chunk). So in 1990 he turned from the docks to the Cambridge, Massachusetts-based Institute of Circadian Physiology's research labs, rounding up some willing test subjects and dividing them into three groups. Each group would sleep only three hours in 24. One group would take all three hours at once. A second would sleep an hour and a half at night and then take three naps during the day. And the last group-the true polyphasics-would accumulate all their sleep in half-hour naps every four hours. Stampi began by testing the performance of his subjects when they were getting a full eight hours of normal sleep, administering a short cognitive test that was easy to repeat. Then he had them shift to their three-hour routines. After more than a month, the monophasic group showed a 30 percent loss in cognitive performance. The group that divided its sleep between nighttime and short naps showed a 25 percent drop. But the polyphasic group, which slept exclusively in short naps, showed only a 12 percent drop. Stampi was not surprised by the numbers. As he explained to me, there are two types of sleep: REM sleep, which is important for memory and learning, and non-REM sleep, which restores energy and releases hormones for growth and development. Non-REM sleep occurs in four stages: Stage one is a light slumber; stage two marks the onset of real sleep, where the heart rate and breathing slow; and stages three and four provide the deep (or slow-brainwave) sleep that is most highly restorative. Generally speaking, sleepers cycle through these stages about every 90 minutes, with a pit stop for REM sleep between each cycle. Interestingly, the body seems to want its slow-wave fix first, and racks up most of the slow-wave quota in the first three hours. If you slash eight hours of sleep to four and your body has to triage, you retain 95 percent of the slow-wave sleep while ditching large chunks of REM and stage-two sleep. "That suggests that slow-wave sleep is the most critical," Stampi says. "Sleep charges your battery more at the beginning of the sleep cycle than at the end, so if you take more naps you are recharging more efficiently, because you take that first big charge frequently." Ripping up normal patterns to sleep almost exclusively in short naps sounds extreme, but as Stampi points out, approximately 85 percent of mammals are polyphasic sleepers. In fact, he says, until about 10,000 years ago-before humans developed the tools and skills that allowed them to stop worrying constantly about becoming some hungry predator's next meal-humans probably were too. Infants are polyphasic sleepers, and even today there are remote hunter-gatherer tribes in Malaysia that sleep four to six hours a night and nap frequently during the day. Perhaps the most famous polyphasic sleeper was Leonardo da Vinci, who supposedly slept only 15 minutes every four hours, for a total of 1.5 hours of shut-eye every 24. "That would help explain his prodigious output," Stampi says. "But I suspect he only used that mode when he was rushing to dissect fast-rotting cadavers."
Stampi's point is that not only do you
have to nap; you have to nap wisely-meaning you have to One of the most striking clues from Stampi's data was that sailors hardly ever slept between 6 and 8 p.m. Stampi theorized that the evening "forbidden zone," as he called it, was a vestige of the long-ago era when humans-who were more vulnerable at night-had to spend the early-evening hours wide awake, looking for or preparing a safe place to sleep. It generally made no sense, Stampi concluded, to try to snooze during these hours, because you would be fighting the natural human biorhythm At the same time, Stampi also noted sleep peaks that occurred midafternoon and in the wee hours of the morning. This made scientific sense: Humans tend to be sleepiest (or feel "sleep pressure," as Stampi likes to say) then. Stampi thinks the midafternoon sleep bump is also a vestige of early human life, since the heat of the African sun made that a better time to sleep than hunt. His research also showed that afternoon siestas were chock-full of slow-wave sleep, the type that appears to be most important for recharging the body. To Stampi it seemed obvious that sleep-deprived sailors should try to get at least some of their sleep quota then. The key to napping efficiently, Stampi says, is to get in phase and ride these waves of sleepiness and alertness, so no time is wasted merely trying to get to sleep. "My job is to find other hours of the day for each person where sleep is as efficient," he says, "and to try to find a range of sleeping gears, or nap lengths." That means getting in touch with your
inner sandman. All the monitoring Stampi has done over the years has
supported the anecdotal notion that there are two types of people: morning
people, or "larks," and evening people, or "owls."
The distinction is important for anyone trying to adapt to sleep deprivation.
Larks, Stampi discovered, are good at taking short naps but are not
as efficient late at night, and prefer a more regular routine. Owls,
on the other hand, appear to be excellent at coping with highly irregular
schedules, but prefer longer naps. Mike Golding is an owl, and during
the 1998 Around Alone, only 23 percent of his sleep time was devoted
to naps of less than an hour. Ellen MacArthur, in contrast, is more
of a lark and tends to spend 60 percent of her sleep time in naps shorter
than an hour. Despite the different styles, both Golding and MacArthur
sleep about the same amount while racing, between 4.5 and 5.5 hours
on average in every 24-the minimum amount, Stampi believes, on which
humans can get by. Anneke Heitmann, research director at Circadian Technologies, in Lexington, Massachusetts, once worked with Stampi on some of his sleep-deprivation experiments. She thinks a Stampian approach could benefit these extreme athletes. "A polyphasic regimen gives your body more chance to repair," she says. How about the rest of us? Sleep researchers, including Stampi, agree that if you have the option of snoozing a solid seven or eight hours per night, then taking it is the best strategy for being a well-rested, efficient human being. But if you can't pull it off, a Stampian approach might help keep you upright with less than sufficient sleep. Before I joined him in Newton, Stampi sent me a wrist sleep monitor. For two weeks I tried a variety of extreme sleep patterns. I started with the great Leonardo and tried to sleep just 15 minutes every four hours. After two days I was a walking ghoul, barely able to make a pot of coffee. I decided to go for an Ellen MacArthur solo-sailor pattern, with one to three hours of sleep in the middle of the night and enough 20- to 30-minute naps to get my sleep total up to about five hours in 24. This was a lot better, but, absent the threat of dying at sea, it got harder and harder to limit the overnight sleep to just three hours. Ultimately I gravitated toward a five- or six-hour chunk of sleep at night, supplemented by a 25-minute nap in the sleepy part of the afternoon. Now I was getting somewhere, and when Stampi eventually downloaded all my sleep data from the wrist monitor, he wasn't surprised. He diagnosed me as a hybrid owl/lark, but with the owlish preference for longer sleep periods. "What's your schedule?" I asked him. "Pretty much the same as yours," said Stampi, who slumbers six hours a night, with a 15-minute nap in the afternoon. "I never feel tired." As for Joe Harris, it took the Transat for him to discover where exhaustion ends and a coma begins. "I'm so much more aware of my sleep patterns now," says Harris, who is working with Stampi to prepare for the 2006 5-Oceans Solo Race (formerly the Around Alone). Winning races, or even just getting extra hours in a day, is not a bad trade-off for a little less shut-eye, so Dr. Sleep has an interesting bargain for a tired world. But don't call him after lunch. He'll be napping.
Short-Wavelength Sensitivity for the
Direct Effects of Light on Alertness, Vigilance, and the Waking Electroencephalogram
in Humans Interventions: Subjects were exposed to equal photon densities (2.8 x 1013 photonso cm-2o s-1) of either 460-nm (n = 8) or 555-nm (n = 8) monochromatic light for 6.5 hours, 15 minutes after mydriasis. Measurements and Results: Subjects underwent continuous EEG/electrooculogram recordings and completed a performance battery every 30 to 60 minutes. As compared with those exposed to 555-nm light, subjects exposed to 460-nm light had significantly lower subjective sleepiness ratings, decreased auditory reaction time, fewer attentional failures, decreased EEG power density in the delta-theta range (0.5-5.5 Hz), and increased EEG power density in the high-alpha range (9.5-10.5 Hz). Light had no direct effect on cortisol. Conclusions: Short-wavelength sensitivity to the acute alerting effects of light indicates that the visual photopic system is not the primary photoreceptor system mediating these responses to light. The frequency-specific changes in the waking EEG indicate that short-wavelength light is a powerful agent that immediately attenuates the negative effects of both homeostatic sleep pressure and the circadian drive for sleep on alertness, performance, and the ability to sustain attention.
Caffeine Free: Blue Light Makes People
Alert at Night posted: 01 February 2006 There's much more than meets the eye to how we perceive light, researchers have learned in recent years. The latest revelation: blue light helps fend off drowsiness in the middle of the night. A small study of 16 volunteers found that exposure to short-wavelength light, or blue light, perked them up immediately. "Light exposure to this system, particularly blue light, directly reduces sleepiness, said Steven Lockley of the Brigham and Women's Hospital. Subjects exposed to blue light were able to sustain a high level of alertness during the night when people usually feel most sleepy, and these results suggest that light may be a powerful countermeasure for the negative effects of fatigue for people who work at night." The study, sponsored by National Space Biomedical Research Institute, is detailed in the Feb. 1 issue of the journal Sleep. "The effects lasted as long as the blue light was on, which was 6.5 hours," Lockley told LiveScience. "I expect it would last at least for a few hours more if we extended the light exposure for longer although not ad infinitum. We hope to do studies with longer exposures shortly." The work adds to other evidence that the human eye sees things we're not consciously aware of. Other research has shown that the eye's hidden perceptive abilities help control our 24-hour internal clock, so we know when to sleep and when to wake. "These findings add to the body of evidence that illustrates that there is a novel photoreceptor system that exists in the human eye in addition to that used for sight," Lockley said. Eventually the finding could lead to ways to improve alertness in nighttime drivers, shift workers, pilots or astronauts, said Lockley, who is also an Assistant Professor at Harvard Medical School. More work needs to be done, however. Blue light in the wrong doses can be dangerous to the eye.
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