Sleep is essential for all aspects of health, according to neuroscientist Mathew Walker, author of NYT best seller Why We Sleep: Unlocking the Power of Sleep and Dreams. Sleep is vital for maintaining immune system, cardiovascular and reproductive function. It helps improve memory, psychiatric disorders and neurodegenerative decline and prevent cancer. Yet, according to a National Sleep Foundation survey (in the US, Canada, UK, Germany and Japan) at least 50% of people don’t get sufficient sleep (7 hours or more) on weekdays. If you routinely get 5 to 6 hours of sleep your body, mind and well-being are paying the price. Sleeping longer on weekends doesn’t replenish your sleep deficit.
If you think you are one of those people who can function on less sleep than the rest of us, you are wrong. Only 1% of he population carry a gene that allows them to function optimally on less than 5 or 6 hours of sleep. According to Walker you are more likely to be struck by lightning than to have this gene.
Dream and slow-wave sleep cycles
During sleep our brain waves move through different cycles throughout the night. As we begin to “fall” into sleep slower alpha and theta waves increase. When we dream theta waves are in the REM (rapid eye movement) stage. Here our brain processes all the information from our day integrating it with past experiences. This phase creates a foundation for understanding our life and the world around us and provides insights and problem-solving abilities. The dream stage is essential for processing and regulating emotions. Research has shown how dreaming about traumatic events allows us to process and move past them.
Our cycle of deepest sleep—slow-wave cycle—is known as NREM (non-rapid eye movement) when we do not dream and delta brain waves, slowest of all, take over. This stage allows our brains to store, strengthen and consolidate memories of what we learned. It’s the brain’s way of housecleaning—cleansing, repairing and clearing out wastes. If this process doesn’t take place, or is significantly reduced, it can contribute to the development of Alzheimer’s disease. During slow wave sleep your body goes about the healing and regenerative processes that help strengthen your immune system, hormones, cells and mental health. Slow-wave sleep is also the time in which information learned during the day is stored and processed by the brain.
BETTER SLEEP CYCLES
Effects of caffeine and alcohol
Caffein can help us feel alert and energized, no doubt about it. On the downside, however, caffein blocks adenosine receptors in the brain that create our desire to sleep. This may be fine in the morning, but not later in the day, since this blocking process continues long after ingesting caffein. For example, drinking a cup of coffee at noon, half of the caffein is still energizing our system, on average, 5 hours later. It still can take another 5 hours or more to fully release its affects. As a result we may have difficulty falling asleep.
On the other hand, although alcohol initially acts as a sedative, it actually is a powerful suppressor of REM sleep—even in moderation. Going to bed with alcohol in our system, disrupts the second half of our sleep significantly. So, our sleep is not continuous and restorative.
Our bodies like regularity in everything: timing of sleeping, waking, eating, etc. Like plants lifting their leaves in daylight and lowering in darkness, almost every aspect of our daily life is rhythmic and regulated—essentially programmed—by our internal circadian clocks. Every organ has its own circadian clock, even every cell.
Both daytime and evening activities have a huge effect on our circadian rhythms. Our eyes receive and send light signals to our brain to tell it when it’s morning and night. Exposing ourselves to enough daylight and/or blue spectrum lighting earlier in the day, helps us fall asleep faster at night. But, towards evening, incandescent warmer yellow-red and dimmer lighting increases the rise of melatonin. This hormone tells your body it’s time to sleep by lowering your alertness and reducing body temperature.
How much and when to sleep
Walker says that adults need an average of 8 hours of sleep each night to maintain optimal health. The National Sleep Foundation, the American Academy of Sleep Medicine and the Sleep Research Society recommend between 7 to 9 hours per night. However, adolescents need 9.25 hours on average. NREM sleep is essential in the brain maturing into adulthood. When Edina, Minnesota shifted their high school start time for 7:30am to 8:30am, it resulted in increased SAT scores, attendance and graduation rates and less depression.
I found it interesting that humans were originally biologically hardwired to sleep in two different periods in a 24-hour day. Have you ever noticed a dip in your alertness mid-afternoon? Walker recommends taking a short nap, 30 to 60 minutes, during the early afternoon. Some Mediterranean European and South American cultures still allow for an afternoon siesta. Harvard University researchers followed 23,000 Greek adults over a six-year period. Their findings revealed that people who took afternoon naps had a 37% lower risk of death from heart disease than those who did not. Interestingly working men in particular showed a 60% reduced risk.
Every Thursday at 1 pm CST, I offer free guided iRest meditations. iRest is based on an ancient practice of Yoga Nidra known as “sleep of the yogis.” Participants sit or lie down sinking into deep relaxation, often bordering on sleep. Afterwards they arise feeling refreshed and regenerated. Learn more about iRest and my meditations and try one at the end of this article.
Preparation for better sleep
Is it time for you to evaluate your daily routines so you can sleep better, deeper and feel healthier? How might you create new habits and even bedtime rituals to calm your busy mind and release tension. What activities can you avoid that create anxiety or cause your heart pump faster before bedtime?
Consider relaxing with meditation or breathwork before retiring. Meditation has been shown to allow the slower brain waves of theta and even delta to increase. Gentle practices like yoga and Clinical Somatic Movement have a similar effect as you release muscle tension to help enhance better sleep.
Learn more about Somatic Movement
Experience Somatics in a Zoom or in-person class
Try this guided meditation practice
to ease into better and deeper sleep.