"More than 85 percent of mammalian species are polyphasic sleepers, meaning that they sleep for short periods throughout the day," according to the National Sleep Foundation. We're the odd mammals out. For the most part, our days are divided into two distinct periods, one for sleep and one for wakefulness, and still 40 percent of us get less than the recommended seven hours of sleep each night, according to a 2013 Gallup poll. Now, naps can't make up for our sleep deficit, but they can certainly improve our efficiency at work, enjoyment of activities, and overall well-being in life. But before we get into all the health benefits, take a look at the NSF's tips for good napping.
It may seem silly, but there are actually three types of naps.
1. Planned or Preparatory Napping: For the planner among us who strategically takes a nap even before sleepiness sets in as preparation for an overnight shift or three-night bender.
2. Emergency Napping: For the serial napper who's overcome with sudden bouts of sleepiness that simply cannot be shaken—or the guy who works with heavy, dangerous machinery, or drives a truck for a living.
3. Habitual Napping: For those of us who love the notion and practice of siestas and take a nap at the same time each day; this also includes young children who nap after juice and cookies.
The NSF recommends 20-30 minute naps for short-term alertness and improved performance. Just be sure you don't take one too early or late in the day; your body may not be ready for sleep yet early in the morning, and taking one late in the evening can throw off your natural sleep patterns, disrupting restorative sleep through the night. Remember, naps aren't reserved for children, the elederly, or the lazy. In fact, a power nap can be just the antidote for laziness.
A quick 20-30 minute nap can boost short-term alertness, according to the National Sleep Foundation. It won’t leave you in a grumpy, hazy fog or interfere with sleep later at night either.
A midday snooze shouldn’t be frowned upon or chalked up to laziness. A nap can reverse information overload and protect your brain from mental burnout, according to a news release from The National Institutes of Health. Subjects who were allowed to take a 30-minute nap after after performing two of four visual task sessions on a computer prevented extended deterioration of their performance, while a one-hour nap actually boosted their performance in the remaining third and forth sessions.
The midday slump is programmed into our circadian schedule, so it’s only natural to feel an onset of sleepiness around 3 p.m. There are numerous ways to get past it, but taking a nap is most effective, according to material from Harvard Health Publications. Napping helped restore alertness better than preemptive nighttime sleep and using caffeine to cope with afternoon sleepiness.
Naps can improve work performance and reduce mistakes and accidents, according to information from the National Sleep Foundation. In fact, NASA conducted a study on sleepy military pilots and astronauts and found a 40-minute nap improved their performance by 34 percent and alertness by 100 percent.
Midday naps appear to lower blood pressure levels and decrease the number of necessary antihypertensive medications in men and women with high blood pressure, according to a press release from the European Society of Cardiology. Patients who slept for 60 minutes midday had significantly lower blood pressure compared to patients who didn’t sleep midday. The researchers add: “We found that midday sleep is associated with lower 24 hour blood pressure, an enhanced fall of BP in night, and less damage to the arteries and the heart. The longer the midday sleep, the lower the systolic BP levels and probably fewer drugs needed to lower BP.”
Researchers at Saarland University in Germany tested the theory of power napping on 41 students, Independent reports. They split the group in two, taught each 90 words and 120 unrelated word pairs (like “milk taxi”), then allowed one half to nap for 45-60 minutes while the other watched a DVD. The snoozers’ memories were amplified five-fold, according to the study, which was published in the journal Neurobiology of Learning and Memory.
Research from Georgetown University’s Center for Functional and Molecular Imaging in Washington indicated that when people nap, the left brain—known for logic and analyzing—rests and is relatively at peace quietly, while the right side of the brain—in charge of creativity and big-picture thinking—communicates with itself and the right side of the brain. And you thought napping was mindless.
If you’re sleep deprived, take a 30-minute nap; it can help your immune system, according to a small study published in The Journal of Clinical Endocrinology & Metabolism. The researchers collected urine and saliva samples from 11 young, healthy men each day to measure their levels of norepinephrine—a substance typically released when the body is under stress, which increases heart rate, constricts blood vessels, and raises blood pressure and blood sugar. Half the men slept normally for one night, then restricted to two hours the second night, and allowed to sleep as much as they liked on the third. The other half followed the same schedule, only they were allowed to take a 30-minute nap the day after their sleep was restricted. When the men were only allowed to sleep for two hours, their norepinephrine levels were more than doubled (in the afternoon) compared to when they were allowed to sleep normally. However, there was no change in norepinephrine when participants were allowed to nap.
People who took afternoon siestas of 30 minutes or more at least three times a week had a 37 percent lower risk of dying from heart disease than those who didn’t, according to research from the Harvard School of Public Health (HSPH) and the University of Athens Medical School in Greece. The study, which was published in the Archives of Internal Medicine included 23,681 seemingly healthy men and women, ages 20 to 86, and went on for more than six years, Scientific American reports.
Sleep deprivation is linked to junk food cravings, according to a study from UC Berkley. When you skimp on shuteye, the lack of sleep impairs activity in the brain’s frontal lobe, which governs complex decision-making, and increases activity in deeper brain reward centers so you’re more apt to reach for cronuts and pierogis than steamed veggies and salmon.
When we sleep, our brain is busy clearing out the toxic waste that’s been accumulating all day. In a study conducted on mice, published in the magazine Science, researchers found when mice napped the space between cells in their brains increased by 60 percent, allowing the flow of cerebrospinal fluid—as well as an Alzheimer's-linked protein—to flush through the brain very quickly. When they were woken, the flow in their brains was constrained.
When you're tired, you usually get hungry because you're body is urging you to get energy. Likewise, when you're asleep your body reduces levels of ghrelin, your hunger hormone. A study in the journal PLoS Medicine showed a strong correlation between short sleep duration with high levels of hunger-inducing ghrelin, low levels of satisfaction-inducing leptin, and higher rates of obesity. Instead of reaching for a Snickers, take a quick snooze.
Researchers at Berkley University had participants complete a daily survey for two weeks. When they woke up each morning, they recorded how well and for how long they’d slept the previous night, and each night before bed they said whether, and how much, they’d fought with their partner that day. As you can imagine, the poorer people slept the night before, the more they bickered.
If you’re learning a new task at work or undergoing a graduate degree, you need all the help you can get when it comes to learning and retaining information. A University of California study found that naps can actually clear information from your brain’s temporary storage areas, effectively making room for new knowledge to be absorbed. Researchers asked participants to complete a challenging task midday, then at 2 p.m. half the volunteers napped for 1.5 hours while the rest stayed awake. Later that day, at 6 p.m., the nappers performed better than they had that morning, while the non-nappers’ performance faltered.
Might want to take a nap before heading out for a long night of drinking and debauchery: Sleep deprivation can trick you into thinking a woman is into you when she’s really not, reports the Daily Mail. Researchers from Hendrix College had 60 men and women complete a questionnaire before and after one night of sleep deprivation—to which they answered questions on their sexual interest, sexual intent, how interested they were in commitment, and a general interested in the opposite sex. When men were limited on the number of hours spent sleeping, they were more interested in casual sex (scores, on average, rose from 13.5 to 17.5). When you need sleep, your frontal lobe—which is in charge of judgment, impulse control, and social and sexual behavior—is negatively impacted.
People who are sleep deprived are more likely to fall victim to a motor vehicle crash, industrial disaster, and medical and other occupational errors, according to the Centers for Disease Control and Prevention. Taking a nap after a night of fitful sleep or no sleep at all can literally save your life.
If you’re not getting enough sleep on a chronic level, you’re more likely to suffer from diseases like hypertension, diabetes, depression, obesity, and cancer. Plus, you're at risk for increased mortality risk and reduced quality of life, according to reports funded by the National Institutes of Health published in Sleep Disorders and Sleep Deprivation. Napping won't entirely make up for your sleep deficit, but it can definitely help.
Sleep lowers testosterone levels in healthy young men, according to a University of Chicago Medicine study. Subjects spent three nights in a laboratory for 10 hours each night, then eight nights sleeping less than five hours each night. Researchers sampled their blood every 15 to 30 minutes for 24 hours during the last day of the 10-hour sleep phase and the last day of the five-hour sleep phase. Just one week of sleep deprivation decreased their T levels by 10 to 15 percent. If you want to keep your energy, concentration, and boners up, then take special care to get sufficient sleep, or pencil in a nap before date night.
Sleep-deprived employees were better able to control their impulsive behavior and resist “unethical temptations” (i.e. tell your boss off), when employees were provided with the time and space to nap during work, caffeine, and given overtime restrictions and frequent breaks, according to their new study published in the Journal of Applied Psychology.
Sleep deprivation doesn’t just make you groggy and edgy, it can up your odds for developing a full-blown anxiety disorder, according to a University of California Berkley study. When you don’t get sufficient sleep, regions in your brain that contribute to excessive worrying and anxiety light up. Naps can calm your brain temporarily, but make sure to get a full-night's worth of restorative sleep to keep your brain sharp.