I’m going to introduce you to the idea that 8 hours of sleep is actually a MYTH. Not only that, but its a myth perpetuated only 10 miles from my current location in Scotland.
A lot of people find it difficult to get a full night’s rest. But is getting 8 hours of sleep really necessary to be fit, or is it healthy to operate with less?
Get-Fit Guy is hosted by Kevin Don. A transcript is available at Simplecast.
Have a fitness question? Email Kevin at getfitguy@quickanddirtytips.com or leave us a voicemail at (510) 353-3014.
Find Get-Fit Guy on Facebook and Twitter, or subscribe to the newsletter for more fitness tips.
Get-Fit Guy is a part of Quick and Dirty Tips.
Links:
https://www.quickanddirtytips.com
https://www.facebook.com/GetFitGuy
https://twitter.com/GetFitGuy
https://www.kevindon.com/
Welcome back to Get-Fit Guy—Coach Kevin Don here. This past week, I took an Uber ride to coach karate and on the way, the driver asked me what I do for a job. Upon finding out, he asked me if it was true that you need 8 hours of sleep and if it was bad for your health not to get it—he, like many of us do, was finding it difficult to get a full night’s sleep. So, here I am, to share the answer with the Get-Fit Guy audience. I’m going to introduce you to the idea that 8 hours of sleep is actually a MYTH. Not only that, but its a myth perpetuated only 10 miles from my current location in Scotland.
The year is 1817 and the location is a purpose-built village on the River Clyde, just outside Glasgow, called New Lanark. New Lanark was a project in “utopian socialism.” The village was the site of huge cotton mills, powered by the river water from the nearby falls. The industrialist owner, Robert Owen, had a number of welfare projects for the workers, who lived on-site, such as schooling (in fact, New Lanark had the first infants school in the UK). Aside from welfare programs to increase happiness and, therefore, productivity, he also coined the idea of 8 hours of work, 8 hours of recreation, and 8 hours of sleep. It is from this tiny village in Scotland that the idea grew. It was later mentioned in the Treaty of Versailles and was the first item on the agenda at the 1919 International Labour Organization meeting, where the 8-hour work day (and therefore 8 hours of recreation and sleep) was ratified by 52 countries.
Just like anything else, quality matters over quantity. There is a lot more to good sleep than purely the number of hours spent in bed. I often wake up feeling more rested and refreshed from a 40-minute nap than I do from an 8-hour sleep. However, one thing we do know for certain is that the right amount of GOOD sleep is critical to health and wellness, both physically and mentally.
So, what IS the right amount of sleep? Well, first, let's take a sleep overview. The first thing to note is that sleep occurs in 4 stages.
Awake: this is where we are lying in bed before falling asleep. This also includes any nocturnal awakenings between the other stages.
Light Sleep: this is where we are falling asleep. Our heart rate falls and body temperature lowers. Brainwaves and respiration rates slow and you may have muscle jerks.
Deep Sleep: this is the most rejuvenating sleep zone. Blood flow increases to muscles to repair them, growth hormones are released, and the brain flushes waste. If you wake up from this phase, you will be groggy and disoriented.
REM Sleep: this stands for Rapid Eye Movement and is where we have our most vivid dreams, our brains make connections, and we process learning. This stage improves memory and cognition.
A sleep cycle including all of the 4 phases of sleep is typically 90-120 minutes long, so we actually pass through each phase multiple times a night. However, certain factors can upset the balance of the types of sleep we get, which affects our health and wellness. Caffeine, for example, may keep us in the awake phase for longer, meaning less of the other phases. Working out causes more damage, which needs to be repaired, so your body will spend more time in deep sleep (if it can get it–think about pre-workouts with caffeine and how that increases your awake time and decreases deep sleep, making it harder to recover). Alcohol has been shown to decrease awake time, but it also dramatically reduces REM sleep time.
So, how much sleep we need depends on getting ourselves through all four cycles. If you slept for an hour, you would have an incomplete cycle, so for sure that wouldn’t be enough. Likewise, if external factors like stress, caffeine, or room temperature meant you were not getting enough time in deep sleep or REM sleep, you may need more cycles of sleep in a day to check off the box of each sleep phase. Newborns are recommended to get 14-17 hours of sleep because they are growing and their brains are making so many new connections. Those aged over 60 are recommended to aim for 7-9 hours of sleep.
So, if the idea of getting 8 hours of sleep in one go is a by-product of the industrial revolution, what did people think before that tiny town in Scotland was built? To that, we’ll turn to the research of Professor Roger Ekirch. In the 1990s he was visiting the Public Record Office in London and something from a 1699 manuscript caught his eye as unusual. It was mention of a “first and second sleep.” It was something he had never heard of and so he decided to dig deeper. Over the coming months, in manuscripts as far back as the 8th century BC and from as far and wide as Africa, the Middle East, and Australia, he found the same thing mentioned again and again. It seemed that it was a societal norm to sleep in two distinct blocks of sleep.
This concept has since been backed up in contemporary research. A sleep scientist from the National Institute of Mental Health conducted a study where subjects with “normal” sleep habits of a singular long sleep were placed in an environment without daylight, and over the course of four weeks, every single participant had moved into sleeping in two sleep windows of equal length. To add to this, researchers in 2015 who were looking into the living conditions of tribal people in a remote area of Madagascar found that they were, in the absence of modern technologies, sleeping in this biphasic sleep cycle of two distinct sleep periods.
Why did this habit disapear? Other sleep researchers have traced our inability to sleep in two phases to Paris in the early 1600s, when it became the first city in the world to introduce street lighting, to be followed by 50 other major cities across Europe over the next century. Suddenly, being awake at night and going out on well-lit streets to bars and other activities became fashionable and the idea of a first sleep and a second sleep disappeared, with people preferring to be seen out and about in Paris and London.
So, should we all now be trying for biphasic sleep? I would say that modern living has made that very difficult. More important than either biphasic sleep or an 8-hour block is that we get the right amount of sleep across the day and that we ensure we get time in each phase of sleep. So, making it easier to fall asleep by keeping the sleeping area cool and dark is important, as is removing stimuli like television and cell phones immediately prior to attempting to go to sleep. Caffeine and alcohol, with their effects on getting into light sleep with the former and into REM sleep with the latter, are also best avoided.
If you have any questions about your sleep or just want to say hi, head over to the Get-Fit Guy Facebook page or send me an email at getfitguy@quickanddirtytips.com.