The Function of Sleep
If resting in bed were all it took to recharge body and mind for the coming day, insomniacs could take in their favorite late night television and start the next day fresh. But surprisingly, it's not how much sleep you get that's important—it's the level of sleep you achieve that truly restores you, body and mind.
Sleep can be divided into 2 crucial phases:
- Non-rapid eye movement (NREM) sleep takes up about 75% of the average sleeper's night. The earliest phase of NREM sleep begins with general relaxation of muscles. This relaxed state eventually culminates in the deepest sleep level when it appears that protein synthesis, growth hormones, immune function, and the mind are given a boost. Delta waves—the slowest and largest waves—signal the onset of this most rejuvenating sleep level.
- Rapid eye movement (REM) sleep takes up about 25% of an average dreamer's night. Dreams that occur during REM sleep might provide, in a sense, a sorting through of free-floating information. REM sleep is thought to be a very important period for mental revitalization.
Risky Consequences From Sleeplessness ^
In addition to productivity and safety consequences, research shows that people who have insomnia or are chronically sleep deprived may be more likely to have an increased risk of:
People who do not get enough sleep may also:
- Have behavioral problems
- Drink more alcohol and use more sedatives than they usually do
- Experience a decreased enjoyment in life
Those Most Affected ^
Late Shift Workers
Late or overnight healthcare, military and public safety workers, nuclear power plant operators, medical residents, and long-haul truck drivers, have work schedules that are contraray to the body's natural circadian rhythm. Circadian rhythms dictate that the longest period of sleepiness occurs during the hours of 2:00-4:00 am. Thus, people who work these shifts lose may out on the time that the body is programmed for the deepest and most beneficial sleep.
Older adults also cope with their own difficulties that keep them from getting the sleep they need. For many, aging brings on a host of health-related problems that interrupt sleep, such as pain from arthritis or other conditions, or side effects from medications. More than any other population, older adults rely on medications to manage multiple conditions. Moreover, a more sedentary lifestyle doesn't allow for the expenditure of energy that results in restful sleep. Lastly, the brain doesn't allow for the same degree of deep sleep per night as enjoyed in youth.
None of this means that the older adults don't need as much rest as everyone else. The combination of conditions that change sleep habits only indicates that adjustments need to be made in order to get the proper amount of sleep.
Tips for Better Sleep ^
In general, people are so used to going without enough sleep that they don't recognize that their sleeping habits make sound slumber unlikely. Following these simple tips will help you settle down for a good night's rest. Do the following to improve the quality of your sleep as well as to get more restful sleep:
- Avoid caffeine, nicotine, alcohol, and exercise at least 4 hours before bedtime—Caffeine and nicotine are stimulants. Since alcohol is a depressant, it can make falling asleep easier. However, it interferes with deep sleep later on during the night. Exercise also acts as a stimulant, but a workout earlier in the day can improve nighttime rest.
- Leave worrying outside the bed—If you stay awake worrying about things you have to tackle the next day, write out a list of "to-dos" to take the pressure off. Then put the list aside to deal with the next day. After all, it's not likely you can deal with these problems in the middle of the night.
- Keep other activities out of the bedroom—Don't confuse your bedroom with your family room. Keep your television viewing and Internet surfing out of your sleeping quarters. You need to associate your bedroom with sleep and not activities that will keep your mind engaged.
- Don't try to force yourself to sleep—You'll just lie awake staring at the clock. After 20 minutes of wakefulness, go to another room to read or perform some other quiet activity. Return to your bedroom only when you've become tired enough to sleep.
- Temperature counts—Keep your bedroom set up for a restful night's sleep with a comfortable mattress and proper temperature setting. A too-hot or too-cold room can keep you awake.
- Reduce noise levels—Apartment-dwellers with noisy neighbors or those on heavily trafficked streets can block out noise with a fan, white noise machine, or ear plugs.
- Avoid stimulation before sleeping—Try not to engage in anything that will give you a boost of energy just before bed, such as viewing an action-packed movie or sitting in a brightly lit room. Instead, try listening to soothing music or reading.
- Slow down—Don't hurriedly get ready for bed at the last minute. Brush your teeth and wash yourself a while in advance. Try to stick with an early-to-bed, early-to-rise pattern. That way, you won't go to bed too late during the work week and need an alarm clock each morning to wake you out of a sound sleep.
If you're troubled with chronic difficulties falling asleep—or staying asleep—see a doctor. Sleep disorders are very common and can be treated.
American Academy of Sleep Medicine
National Sleep Foundation
Better Sleep Council Canada
Canadian Sleep Society
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Sleep drive and your body clock. National Sleep Foundation website. Available at: https://sleepfoundation.org/sleep-topics/sleep-drive-and-your-body-clock. Accessed October 2, 2017.
What happens when you sleep? National Sleep Foundation website. Available at: https://sleepfoundation.org/how-sleep-works/what-happens-when-you-sleep. Accessed October 2, 2017.
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Last reviewed October 2017 by EBSCO Medical Review Board Michael Woods, MD Last Updated: 11/3/2015