Could you keep it down? Can't you see we're trying to get a little shut-eye?
Sleep. It rejuvenates. It refreshes. It restores. And while it may seem as if sleep renders us inactive, the truth is quite the contrary. Our bodies, our brains, our minds are accomplishing great things while we slumber.
Dr Nilesh Dave, medical director of the Sleep and Breathing Disorders Centre at University of Texas Southwestern Medical Centre, says: "When you get good-quality sleep and enough hours of it, it is amazing how much better patients' moods are, how much better they're functioning. They're truly happy."
During a series of studies in the 1980s, rats were forced to stay awake. After five days, they started dying.
In 2005, a 28-year-old South Korean man died after playing an online computer game for 50 straight hours with few breaks.
"You have a full-body collapse," Dr Dave says. "There's no stability in the brain. The body ends up not being able to restore itself."
Here are some benefits of sleep:
1. It makes us better athletes
A 2008 study by the Stanford Sleep Disorders Clinic and Research Laboratory found that swimmers who got extra sleep swam faster, reacted quicker, improved turn time and increased kick strokes.
When basketball players underwent similar sleep studies, their performance improved dramatically, too.
Conversely, not enough sleep has the opposite effect. Studies cited in Runner's World link longtime sleep deprivation to the following: Becoming exhausted more quickly; deterioration in physical performance; higher accumulation of lactate; impaired mental ability; increased heart rate; and a lower volume of oxygen that can be used while exercising.
Even short-term sleep loss, however, can impede glucose metabolism in certain areas of the brain, especially those connected to alertness and visual processing.
Plus, we need sleep to restore muscles exhausted during workouts.
2. It helps us deal with stress and helps us grow
Our bodies use sleep to release certain hormones, Dave says, including those essential for growth and development. If we wake in the middle of the night, those functions are disrupted.
One example is cortisol. For people with normal sleep patterns, this stress hormone peaks around 4 am. We're blissfully unaware because we snooze through it.
But, Dave says, "If you're awake longer than you should be for a few days, that puts your body under stress, which leads to higher levels of cortisol."
This, in turn, leads to higher blood pressure, more sugar in the blood (not a good thing for diabetics) and an increased appetite.
Researchers at the University of Chicago found that sleep-deprived subjects were hungry because their levels of leptin - the hormone that tells the brain when you've eaten enough - were low. Subjects were limited to four hours of sleep per night. After six days, they showed signs of developing diabetes.
3. It helps us remember
When you pull an all-nighter to study, you're storing information in short-term memory, Dr Dave says. For long-term retention, you need to learn a little every day.
"During sleep, your brain will process a lot and turn it into long-term memory," he says. "Memory is a function of what we think sleep does."
At the Sleep and Neuroimaging Lab at the University of California, Berkeley, researchers gave 400 subjects a series of letters to type with their left hands. For those who learned the sequence in the morning and were tested 12 hours later, performance stayed pretty much the same.
But those who learned it late in the day and were tested again after a night's sleep improved their performance by 20 to 30 per cent.
4. It is imperative for safe driving
Drinking and driving have long been known to be incompatible. But a 2006 study by the National Sleep Foundation and Virginia Tech Transportation Institute uncovered information equally as sobering: 80 per cent of crashes and 65 per cent of near-crashes involved some sort of "driver inattention." In most cases, that inattention was drowsy driving.
The sleep foundation calls drowsy driving "a silent killer." Like alcohol, it impairs response time and judgment and decreases awareness. But, unlike alcohol, no tests can determine whether a person drifted off into what's called a micro-sleep. Within two seconds while driving a car at 95 km an hour, you could drift into another lane. Within four seconds, you could be off the road.
5. It keeps us from being crabby
Think how much better you feel after a good night's sleep.
"You can see a night-and-day difference if sleep problems are dealt with," Dr . Dave says. "It's a 100 per cent turnaround."
SLEEP BASICS
Knowing what sleep does for you is one thing. Getting a good night's sleep is quite another. These seven tips may help:
1. Establish a bedtime routine.
It helps children settle down, and it can work for adults, too. "Most people don't allocate enough time to unwind," Dr Dave says. "A lot work until they can't keep their eyes open. As soon as they get into bed, they can't sleep. A lot of thoughts are going through their minds."
2. Use the bed only for sleep and sex.
"Otherwise, your brain doesn't realise the bed is for sleeping only," he says. It relates the bed to other activities such as reading or watching television.
3. Make your bedroom dark, comfortable, quiet and cool.
Limit distractions. Put on your pyjamas and sink into the covers.
4. Exercise, but not right before bedtime.
The reasons: Exercise makes us alert, plus it raises our body temperature. A lower body temperature helps you get to sleep easier and faster.
5. Stick with a schedule.
Go to bed and wake up about the same time every day. Even on weekends.
6. Calm your body.
Breathe slowly and deeply. Focus on relaxing your muscles one group at a time.
7. Know when to seek help.
Talk to a doctor for reasons that include the following: If you or your bed partner snore or gasp for breath; if you think you sleep enough but wake up not feeling refreshed for a few weeks; if you have chronic daytime sleepiness.
POPULAR SLEEP POSITIONS
How do you sleep? Here's the breakdown for most of us and how your sleep position tells what kind of person you are.
- Foetal position (on side, legs bent, arms folded prayerlike). Those who sleep this way are tough on the outside, sensitive at heart. More than twice as many women as men sleep this way.
- Log (straight; no bending). These sleepers are social, easygoing and like being part of the in-crowd. Trusting of strangers, they may be gullible.
- Yearner (on side, arms reaching out). They have an open nature but can be cynical, suspicious and slow to make up their minds. Once they've made a decision, however, they're unlikely to change it.
- Soldier (on their backs, arms at their sides). These are generally quiet and reserved. They set high standards for themselves and others.
- Freefaller (on their stomachs, arms grasping the pillow). They're often brash and gregarious, but can be thin-skinned. They don't like criticism.
- Starfish (on their backs, arms grasping the pillow). They're good friends and good listeners.
MCT smh.com.au