The architecture of sleep

Authors: Melinda Smith, M.A., Lawrence Robinson, and Robert Segal, M.A. Last updated: April 2015. Condensed version from HelpGuide.org.

You may think that once you go to bed, you soon fall into a deep sleep that lasts for most of the night, progressing back into light sleep in the morning when it’s time to wake up. In reality, the sleep cycle is a lot more complicated.

During the night, your sleep follows a predictable pattern, moving back and forth between deep restorative sleep (deep sleep) and more alert stages and dreaming (REM sleep). Together, the stages of REM and non-REM sleep form a complete sleep cycle. Each cycle typically lasts about 90 minutes and repeats four to six times over the course of a night.

When you chart the sleep stages over the course of the night, the result looks like a city skyline—which is why it is called "sleep architecture"

The amount of time you spend in each stage of sleep changes as the night progresses. For example, most deep sleep occurs in the first half of the night. Later in the night, your REM sleep stages become longer, alternating with light Stage N2 sleep. This is why if you are sensitive to waking up in the middle of the night, it is probably in the early morning hours, not immediately after going to bed.

Deep sleep

The most damaging effects of sleep deprivation are from inadequate deep sleep. Deep sleep is a time when the body repairs itself and builds up energy for the day ahead. It plays a major role in maintaining your health, stimulating growth and development, repairing muscles and tissues, and boosting your immune system. In order to wake up energized and refreshed, getting quality deep sleep is essential. Factors that can lead to poor or inadequate deep sleep include:

•    Being woken during the night by outside noise, for example, or in order to care for a crying baby.

•    Working night shifts or swing shifts. Getting quality deep sleep during the day can be difficult, due to light and excess noise.

•    Smoking or drinking in the evening. Substances like alcohol and nicotine can disrupt deep sleep. It’s best to limit them before bed.

REM sleep

Just as deep sleep renews the body, REM sleep renews the mind by playing a key role in learning and memory. During REM sleep, your brain consolidates and processes the information you’ve learned during the day, forms neural connections that strengthen memory, and replenishes its supply of neurotransmitters, including feel-good chemicals like serotonin and dopamine that boost your mood during the day.

To get more mind and mood-boosting REM sleep, try sleeping an extra 30 minutes to an hour in the morning, when REM sleep stages are longer. Improving your overall sleep will also increase your REM sleep. If you aren’t getting enough deep sleep, your body will try to make that up first, at the expense of REM sleep.

Improve daytime habits for better sleep

•    Be engaged. Social activities, family, and work can keep your activity level up and prepare your body for a good night’s sleep. If you’re retired, try volunteering, joining a seniors’ group, or taking an adult education class.

•    Improve your mood. A more positive mood and outlook can reduce sleep problems. Find someone you can talk to, preferably face-to-face, about your problems and worries.

•    Exercise regularly. Exercise releases endorphins that can boost your mood and reduce stress, depression, and anxiety.

•    Expose yourself to sunlight. Bright sunlight helps regulate melatonin and your sleep-wake cycles. Try to get at least two hours of sunlight a day. Keep curtains and shades open during the day, move your favorite chair to a sunny spot, or consider using a light therapy box to simulate daylight.

•    Limit caffeine, alcohol, and nicotine. All are stimulants and interfere with the quality of your sleep.

Encourage better sleep at night

•    Naturally boost your melatonin levels. Artificial lights at night can suppress your body’s production of melatonin, the hormone that makes you sleepy. Use low-wattage bulbs where safe to do so, and turn off the TV and computer at least one hour before bed.  

•    Don’t read from a backlit device at night (such as an iPad). If you use a portable electronic device to read, use an eReader that is not backlit, i.e. one that requires an additional light source such as a soft bedside lamp.

•    Make sure your bedroom is quiet, dark, and cool, and your bed is comfortable. Noise, light, and heat can cause sleep problems. Try using a sleep mask to help block out light.

•    Use your bedroom only for sleep and sex. By not working, watching TV, or using your computer in bed, you’ll come to associate the bedroom with sleep and sex, so when you get into bed your brain and body get a strong signal that it’s time to nod off or be romantic.

•    Move bedroom clocks out of view. Anxiously watching the minutes tick by when you can’t sleep is a surefire recipe for insomnia. Light emitted from a clock, telephone or other device can also disrupt your sleep.

Keep a regular bedtime routine for better sleep

•    Maintain a consistent sleep schedule. Go to bed and wake up at the same times every day, even on weekends.

•    Block out snoring. If snoring is keeping you up, try earplugs, a white-noise machine, or separate bedrooms.

•    Go to bed earlier. Adjust your bedtime to match when you feel like going to bed, even if that’s earlier than it used to be.

•    Develop bedtime rituals. A soothing ritual, like taking a bath or playing music will help you wind down. Relaxation and stress management techniques, such as deep breathing and progressive muscle relaxation, take some practice but their benefits can be substantial. 

•    Limit your use of sleeping aids and sleeping pills. Many sleep aids have side effects and are not meant for long-term use. Sleeping pills don’t address the causes of insomnia and can even make insomnia worse in the long run. Therefore, it’s best to limit sleeping pills to situations where your health or safety is threatened.

•    Combine sex and sleep. Sex and physical intimacy, such as hugging and massage, can lead to restful sleep.

The importance of regular exercise in overcoming sleep problems

Exercise releases chemicals in your body that promote more restful sleep. There are four main types of exercise:

•    Aerobic activities, such as walking, swimming, or riding a bike, increase your heart rate and breathing to improve the health of your heart and circulatory system.

•    Strength exercises build muscle tissue and reduce age-related muscle loss.

•    Stretching exercises keep your body limber and flexible, allowing a greater range of motion as you age.

•    Balance exercises build leg muscles to reduce the chances of a fall.

While adults need some of each type of exercise, studies have shown that participating in moderate aerobic activity can have the greatest impact on improving sleep.

Adding exercise to your life does not necessarily mean signing up for a gym membership. There are countless activities you can do to increase strength, improve aerobic capacity, burn calories, and prepare yourself for a good night’s sleep at the end of the day. Always consult your doctor before embarking on any new fitness program.

•    Swim/Water exercises – Swimming laps is a gentle way to build up fitness and is great for sore joints or weak muscles. Many community and YMCA pools have swim programs just for older adults, as well as water-based exercise classes such as water aerobics.

•    Dance – If you love to move to music, go dancing or take a dance class. Dance classes are also a great way to extend your social network.

•    Take up lawn bowling, bocce, or pétanque – Variations on throwing a ball on an earthen or grassy court are gentle ways to exercise. The more you walk, and the brisker the pace, the more aerobic benefit you’ll experience.

•    Golf – Golf is a form of exercise that requires precise, strong movement of particular parts of your body, but which doesn’t require vigorous movement. Walking can be an added aerobic bonus to your game.
Cycle or run – If you are in good shape, you can run and bicycle until late in life. Both can be done outdoors or on a stationary bike or treadmill.

Getting back to sleep at night

It’s normal to wake briefly during the night but if you’re having trouble falling back asleep, the following tips may help:

•    Don’t stress. Try not to stress over the fact that you can’t get back to sleep, because that very stress encourages your body to stay awake. Focus on the feelings and sensations in your body instead.

•    Make relaxation your goal, not sleep. Try a relaxation technique such as deep breathing or meditation, which can be done without getting out of bed. Remind yourself that although they’re not a replacement for sleep, rest and relaxation still help rejuvenate your body.

•    Do a quiet, non-stimulating activity. If you’ve been awake for more than 15 minutes, try getting out of bed and doing a non-stimulating activity, such as reading a book. Keep the lights dim so as not to cue your body clock that it’s time to wake up, and avoid TV and computer screens.

Postpone worrying. If you wake during the night feeling anxious about something, make a brief note of it on paper and postpone worrying about it until the next day when you are fresh and it will be easier to resolve.

Cognitive behavioral therapy (CBT) for insomnia

CBT is aimed at not only improving your sleep habits but also changing your thoughts and feelings about sleep that may be causing stress and contributing to your insomnia.

If you don’t have access to or can’t afford face-to-face therapy, some online CBT for insomnia programs may offer a cheaper but viable alternative. No online program can take the place of professional medical evaluation, so it’s important to see your doctor for a diagnosis first.