I think I’ve cracked this sleep thing.
For months now I’ve been waking up feeling great after only being in the sack for a few hours.
The revelation came after years of obsessing with getting the recommended 8 hours in. As a night owl who loves coffee, it rarely happened, but even when it did, I often rose feeling worse.
After eventually realizing that something wasn’t right, I did some digging and found out not everyone thinks 8 is the magic number. In fact, some believe there isn’t one at all.
Another number that’s thrown around by the media is 7—the average number of hours we sleep. This is more likely an effect of society not biology, regulated by television schedules and working hours. Looking back on the sleep patterns of pre-industrial societies supports this as you can see back then we slept between 5.7 and 7.1 hours a night.
So the jury is still out on how many hours we need, but one thing is clear: getting too much sleep is worse than getting too little.
Less is Always More
In an analysis of 16 studies that looked at the sleeping habits of over one million people, Prof Franco Cappuccio, Professor of Cardiovascular Medicine and Epidemiology at the University of Warwick, found surprisingly that longer sleepers tended to die earlier than shorter sleepers.
However it is difficult to measure the impact of too much or too little sleep on our health as they can often be symptoms of underlying diseases and illnesses. For example, sleeping too much is often correlated with depression, and sleeping too little with stress. But when Professor Shawn Youngstedt of Arizona State University, understanding the problems with mass sample groups, conducted a small study with 14 young adults, he saw similar results that supported those of Cappuccino.
Participants of his study were instructed to spend an extra two hours in bed for three weeks. At the end of the study Youngstedt found there was an increase across the board in stiffness, back pain, inflammation, and depressed moods.
His results, although limited, make the long term effects of long sleep sound similar to the effects of prolonged periods of inactivity. Could it be that lying down barely conscious for hours and hours every night is actually detrimental to our health, and even threatening to our life span? Well, just as someone can live a long and happy life sitting at a desk for 12 hours a day, while someone else needs to be doing non-stop physical labour, the numbers each of us need in the pit are just as varied.
If you’re between the ages of 18 and 64, it’s said you’ll function on anything between 6 and 11 hours. Though even these figures are only a guideline, and according to the National Sleep Foundation are secondary to your individual requirements. We know Margaret Thatcher could run a country on just 4 hours, whereas some teenagers can’t leave the house on anything less than 10.
So What’s Your Magic Number?
When we’re all tucked up in bed, the sand man begins to work his magic, kicking off our five state sleep cycle. This is made up of four non-rapid-eye-movement or ‘NREM’ stages, and one rapid-eye-movement or ‘REM’ stage.
We quickly pass through the light sleep state of N1, hang around in N2 for a while until our brain waves slow down, fall into the deeper ‘slow wave’ state of N3 and N4, and finally reach the temporarily paralyzed dream state of REM in N5.
It’s commonly believed this cycle occurs over 90 minutes, but in reality, it can range from anything between 70 and 120 minutes. Just like with ‘the magic number’ of hours, the figure we’re told is just a population average which overlooks the unique and diverse needs of the individual.
We do know however, according to the science, that we need four to five of these sleep cycles in order to feel at our best—meaning, at least theoretically, Thatcher could have been firing on all cylinders after crashing for just 4 hours.
But with the varying cycle times, it’s pretty difficult to predict when you’re in-between your forth and fifth cycle and therefore in the ideal state for waking up.
That’s not all, as the night draws in, the length of our sleep cycle increases.
This should give you an idea of how varied your sleep cycle can be over the course of a night:
- N1: 1-7 minutes
- N2: 10-25 minutes (generally)
- N3: 20-40 minutes (decreasing every cycle)
- N2: Jump back to N2 for around 5-10 minutes before entering REM: 1-5 minutes (increasing every cycle)
So what does this teach us?
- Don’t believe anyone who tells you how many hours sleep you need unless they’ve first monitored your brain waves with an EEG machine while you’re sleeping (with your consent of course).
- Get yourself a bit of tech that’ll monitor your sleep cycles and wake you up in the right stage every morning.
So technology is the way to help better regulate our sleep patterns. But before we get on to that, it’s first important to recognise its role in disrupting them in the first place.
Get Back in Tune With Your Circadian Rhythm
Technology is one of the main reasons we’re out of touch with our biological ‘body clock’, otherwise known as our circadian rhythm. Gadgets, electronics, street lights and any other light-emitting devices disrupt our circadian rhythms and push us further and further out of sync with solar time (the rising and setting of the sun).
The body’s circadian rhythm is managed by the Suprachiasmatic Nucleus (SCN), a group of cells that invoke a bodily response to light and dark signals. These signals send messages through the brain to wake the body up, raising its temperature, producing the hormones we need like cortisol, and reducing others we don’t, like melatonin.
The problem is that when we’re exposed to artificial light in the twilight hours, our SCN responds, believing it’s already time to rise and shine, and engaging the body’s systems for its waking state.
It’s not only the fault of technology though, other factors like noise, hormones, exercise, and stimulants also have similar effects in disrupting our circadian rhythm.
However, the good news is that for over 6 million years our ancestors have lived by the rising and setting of the sun. Therefore, when it comes to changing our habits and resynchronising our circadian rhythm to solar time, all it takes is a little effort to avoid these disrupting factors like artificial light between dusk and dawn.
With that in mind, we can stop exercising and drinking coffee too late, start to wear ear plugs and eye masks while sleeping, and overall make our bedrooms the sanctuaries they need to be in order to foster deep, uninterrupted sleep.
Cheap and Cheerful Sleep Cycle Monitoring
Anywhere from $0 to $500+, you can find a gadget that claims to improve your sleep by monitoring your cycles and picking the right time to bring you back around. Luckily for us, one that does it particularly well comes in right at the bottom of that range.
The majority of the sleep monitoring devices and applications work by picking up on the specific characteristics of the cycle stages. Each stage is characterised by changes in the body like temperature, heart rate, and blood pressure. Now these are hard to measure without a plethora of sensors, but some of these changes we display externally with our movements and breathing rate.
The Sleep Cycle app (available on both iOS and Android), is a nifty little system which uses your phone’s accelerometer and microphone to monitor your sleep cycles according to changes in your movement and breathing rate.
An average night’s sleep
Before you drift off, you set your alarm like usual, tuck your phone under the sheets (or leave it on your nightstand if it’s iOS), and let it get to work. The app will track your activity throughout the night and wake you up within a 30 minute window of your chosen time, depending on when you are in N1—your lightest sleep stage.
Granted it doesn’t completely eliminate the shock of the alarm clock in the morning, but it can make that groggy and irritated feeling a thing of the past.
One of the nicest things about this app is the data it accumulates. Soon you will begin to see a pattern in your cycles, how many you need, and be able to start optimizing your sleep. I’ve found waking up after 4 sleep cycles works best for me, which usually means getting around 6 to 6 and a half hours sleep.
In summary, it’s not about the number of hours we get, but rather the quality and consideration of our sleep cycles that dictate how fresh we feel in the morning.
So disregard broad averages, eliminate disruptive factors like artificial light and stimulants, along with the cat, and let the tech and your body do the rest.
Want to take the next step to rising fresh and optimizing your mornings?
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Joseph is a freelance writer, and the co-creator of Project Monkey Mind—a new blog for the 21st century solopreneur and young professional who wants to lead a more free and fulfilling life.