The Secret to Refreshing Sleep
And 10 simple steps to rest better today.
Posted Jun 29, 2018
"Sleep is the best meditation." —Dalai Lama
We spend about a third of our lives in sleep. But why do we sleep, and how can we do it better?
Sleep is critical to our cognitive performance and long-term mental and physical health. Studies have found that sleep-deprived employees are less satisfied, less productive, and less creative. And they are also more disinhibited and more likely to engage in deviant and unethical behavior. Cabin crew on long-haul flights suffer from frequent jet lag, which has been associated with cognitive deficits, including memory impairment. Despite being leaner and healthier than average, cabin crew are at a higher long-term risk of cancer and diabetes. According to the American Academy of Sleep Medicine (AASM), one in every five serious motor vehicle injuries is related to driver fatigue. People who drive after 17 to 19 hours of being awake actually do worse than people who are above the 0.05 percent drinking-driving limit. Contrary to popular perception, a lack of sleep that builds up over time is even more pernicious than total sleep deprivation: According to one study, the long-term restriction of sleep to six hours or less can lead to cognitive deficits equivalent to up to two nights of total sleep deprivation — but unlike with total sleep deprivation, people are largely unaware of their increasing cognitive deficits. Fatal insomnia, a rare prion disease of the brain, leads to progressively worsening insomnia, which in turn leads to confusion, delirium, and death within an average of 18 months.
Sleep greatly improves learning and memory. It triages memories, consolidating useful ones and discarding unhelpful or "duplicate" ones. It also consolidates procedural memory, the memory of how to do things, which is one reason why athletes build it into their training routines. Olympic athletes recognize that sleep is just as important as diet and training, and aim to sleep at least eight hours a night, with many also making time for strategic naps. As well as memory, sleep enhances mood and cognitive function — one reason why we "sleep on it" and "sleep it off." Subjects limited to four to five hours of sleep a night for one week reported feeling more stressed, angry, sad, and mentally exhausted; and when they resumed normal sleep, they reported a dramatic improvement in mood. In people with a mental disorder, such as depression or bipolar disorder, sustained sleep often suffices to prevent or forestall a relapse, and also plays an important role in recovery. In terms of physical health, the benefits of adequate sleep include fewer food cravings, greater weight loss, fewer viral infections, lower risk of strokes and heart attacks, lower risk of dementia, and longer life expectancy. Last but not least, sleep makes us look younger and more attractive, the so-called "beauty sleep."
So what is the secret to refreshing sleep? During sleep, the brain cycles through four successive stages, the last of which is REM or "rapid eye movement" sleep. Each four-stage cycle takes an average of about 90 minutes, with more time spent in REM before natural awakening. Waking up after REM is associated with feeling refreshed, and subjects who had been awoken after REM performed better on tasks like anagrams and creative problem solving. In contrast, being awoken from deep non-REM sleep can leave us feeling groggy and grouchy — as though we had woken up "on the wrong side on the bed." REM, of course, is also associated with dreaming, which serves critical functions, such as assimilating experiences, processing emotions, and enhancing problem solving and creativity. In fact, the brain can be more active during REM than during wakefulness. Many great works of art have been inspired by dreams, including Salvador Dali’s Persistence of Memory, several of Edgar Allan Poe’s poems and short stories, and Paul McCartney’s "Let It Be." Unfortunately, a great deal of REM can be sacrificed by sleeping short or waking up to an alarm clock, phone call, or phone message — which then leaves us feeling tired and confused. In short, the secret to refreshing sleep is to wake up naturally after a sustained period of REM. There is wisdom in the old saying that "one hour’s sleep before midnight is worth two after."
Sleep is important on so many levels. Yet insomnia — difficulty falling or staying asleep — afflicts as many as one in three people, and almost everyone could do with better, more restorative sleep. Common contributors to insomnia include poor sleeping habits, mental disorders such as depression and anxiety disorders, physical problems such as pain and shortness of breath, certain prescription drugs, and alcohol and drug misuse. The most important causes of short-term insomnia, which is the most common type of insomnia, are a stressful life event, a poor sleeping environment, and an irregular routine.
Without further ado, here are my 10 simple steps to better sleep:
1. Set up a strict routine involving regular and adequate sleeping times. Allocate a time for sleeping (for example, 11 p.m. to 7 a.m.), and don’t use this time for anything else. Avoid daytime naps, or make them short and regular. If you had a bad night, avoid sleeping late, as this makes it more difficult to fall asleep the following night.
2. Devise a relaxing bedtime routine that enables you to wind down before bedtime. This may involve breathing exercises or meditation, or simply reading a book or listening to some music. A hot bath can be helpful: By diverting blood to the periphery, it leads to a drop in core temperature once out of the bath, which encourages sleep. Bright lights and bright screens at nighttime can play havoc with your circadian rhythm (body clock), so avoid TV, computers, and phones before going to sleep.
3. Eat a wholesome evening meal with a good balance of protein and complex carbohydrates. Eating too much can make it difficult to fall asleep; eating too little can disturb your sleep and decrease its quality.
4. Enjoy a hot, non-caffeinated drink, such as herbal tea or hot chocolate, before going to sleep. In time, your hot drink could serve as a sleeping cue.
5. But avoid caffeine and alcohol, particularly in the evening. Levels of adenosine in the brain rise with prolonged wakefulness and lead to sleepiness. Caffeine blocks adenosine receptors, which makes it harder to fall asleep and decreases the overall length and quality of sleep. Alcohol may make it easier to fall asleep, but, like caffeine, it decreases the overall length and quality of sleep, especially restorative REM sleep.
6. Sleep in a familiar, dark, and quiet room that is adequately ventilated and neither too hot nor too cold. Try to use this room for sleeping only, so that you come to associate it with sleep. In time, your room could become another sleeping cue. If necessary, wear a sleep mask and earplugs. And switch off your phone.
7. If sleep doesn’t come, don’t get anxious or annoyed and try to force yourself to sleep. The more aggravated you become, the less likely you are to fall asleep. Instead, try to clear your mind and relax. I find that making myself feel grateful soon sends me off to sleep — and it might also work for you. Alternatively, get up and do something relaxing and enjoyable for half an hour before giving it another go.
8. Exercise regularly. Exercise reduces arousal and anxiety and also helps with other aspects of psychological and physical health. With regard to psychological health, it decreases stress, improves concentration and memory, boosts self-esteem, and directly lifts mood through the release of natural antidepressants called endorphins. With regard to physical health, it helps us to become, or remain, slim and toned, decreases blood pressure and heart rate, increases physical strength and endurance, and improves posture and flexibility.
9. Reduce your overall stress. At the same time, try to do something fulfilling each day. As Leonardo da Vinci said, a well-spent day brings happy sleep.
10. If insomnia persists despite these measures, speak to your doctor. In some cases, insomnia has a very specific cause, such as a physical problem or an adverse effect of medication that requires your doctor’s attention. While sleeping tablets may seem like a solution, they are best avoided in the longer term, because of their adverse effects and high potential for tolerance (needing more and more to produce the same effect) and dependence/addiction — not to mention that the quality of sleep on medication may not be the same as natural, non-assisted sleep. Non-pharmacological alternatives to sleeping tablets include sleep restriction therapy and cognitive-behavioral therapy.
Don't make the common, almost universal mistake of underestimating sleep. Time spent in sleep is time well spent, especially that extra hour or two of REM-rich sleep.
Christian MS & Ellis AP (2011): Examining the effects of sleep deprivation on workplace deviance: A self-regulatory perspective. Academy of Management Journal 54 (5): 913-934.
Naska A et al (2007): Siesta in healthy adults and coronary mortality in the general population. Arch Intern Med 167 (3): 296-301.
American Academy of Sleep Medicine (2009). Drowsy Driving Fact Sheet (PDF).
Williamson AM & Feyer AM (2000): Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occup. Environ. Med. 57 (10): 649–55.
Drummond SPA et al. (2006): Effects of two nights sleep deprivation and two nights recovery sleep on response inhibition. Journal of Sleep Research 15 (3): 261–5.
Van Dongen HP et al (2003): The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep 26 (2): 117-26.
Rasch B & Born J (2013): About Sleep's Role in Memory. Physiol Rev. 93 (2): 681–766.
Dinges D. et al. (1997): Cumulative Sleepiness, Mood Disturbance, and Psychomotor Vigilance Decrements During a Week of Sleep Restricted to 4 – 5 Hours Per Night. Sleep 20 (4): 267–277.