Are you regularly rudely awakened from a deep and peaceful slumber by the sound of your alarm clock chiming in your ear?
Do you want to smash it with a hammer, or throw it out of the window?
It could well be that this desire is your body’s way of telling you that this alarm clock is actually not doing you any favours!
A Very Brief History of Alarm Clocks
Alarm clocks are not a particularly new invention.
The first known mechanical alarm clock inventor is Levi Hutchins, an American who in 1787 invented a personal alarm device to wake him at 4 a.m. He didn’t even have to be at work early, it was simply his “firm rule” to wake before sunrise. Though other alarm clocks existed previously, it seems Hutchins had not heard of them. Atlas Obscura
There are systems that outdate this by a long way, however, with accounts of ingenious systems dating back to Ancient Greece and China from as far back as 2000 years ago.
For most of human history, however, being awoken from a deep sleep by an alarm was a rarity.
Alarms Have Become Widespread Due to Artificial Light
Human beings evolved as diurnal animals – that is, animals that are typically active during the daytime.
We have excellent colour vision when there is plenty of light, which was great for hunting and gathering during the day. At night however, we are blinder than a bat without echolocation.
Though it’s likely the case that humans discovered fire before we were even human, up until the invention of electrical light, humans were reliant on sunlight in order to be able to see in any detail, and therefore to do much of anything useful.
There was therefore no real reason to stay up late (after dark), or wake up early (before sunrise).
I Got Rhythm
Millions of years of evolution on this spinning rock have led to us developing a circadian rhythm that repeats on a 24 hour cycle.
This circadian rhythm is an endogenous mechanism – a rhythm the body will follow independently of outside influences.
For example, if you were trapped in a cave for a week and had no idea if it was night or day, you’d probably still end up alternating between being (mostly) awake and being (mostly) asleep 7 times.
This internal clock is also “entrainable” by external factors however, most notably light.
This is one of the ways by which we eventually adjust to jet lag – if the circadian rhythm was fixed from birth, you’d never recover, but fortunately when you do travel to a different time zone, after a while you synchronise again with the rising and setting of the sun.
In this circumstance, it is obviously a good thing that bright light can disrupt your circadian rhythm. It would be a pain if you had to become nocturnal if you moved to a different timezone.
In our modern world, with bright artificial light available everywhere at the flip of a switch, however, it can also cause problems.
Bright Lights and Big Hormones
Two of the major hormones involved in regulating the sleep cycle are melatonin and cortisol.
As the evening progresses, melatonin levels naturally start to rise as part of the endogenous circadian cycle, causing the brain and body to relax, and eventually putting you in the state of sleep.
In the morning, melatonin levels start to fall again, and cortisol levels begin to rise, your body and brain reactivate, and you wake up again, refreshed.
At least in theory.
The production of these hormones however, is strongly entrained by the presence of bright light.
Bright light suppresses the production of melatonin.
If you are in an environment that is well lit late into the evening, either by lightbulbs, or the glare from computer, TV or phone screens, your body can be tricked into thinking that it is still day time, and therefore doesn’t start producing melatonin as it should.
Without this rise in melatonin, the sleep cycle does not start as it should do, and you may well find it hard to get off to sleep, or may not sleep as deeply and soundly as you would otherwise.
When the morning comes the gradual increase in light which comes as the sun rises would normally start to down-regulate melatonin production, and up-regulate cortisol production.
While cortisol may have a bad rap as a “stress hormone”, it is actually only chronic over production of cortisol that can have negative effects. In the right doses at the right times, cortisol is essential for good health and proper functioning. A spike of cortisol in the morning is essential to wake you up and make you alert and ready for the day.
If, however, you are rudely awakened by an alarm clock shocking you out of a deep slumber before this hormonal shift has taken place, you are going to wake up groggy, disoriented and confused!
This daily cycle of going to sleep late exposed to bright light, then being waken up early in the dark, is working against your body’s inbuilt circadian clock.
Aim for 9 Hours of TDT
TDT stands for Total Dark Time.
Personally, I think this is a much better metric to focus on than sleep for a couple of reasons.
- You can’t control exactly when and how you sleep.
You can however control when you switch off your lights and devices and when you go to bed. Following Epictetus’s dichotomy of control, one should concentrate your efforts where they actually count.
- It is surprisingly hard to know how well you have actually slept.
Sleep studies have found very poor correlation between people’s subjective experience of sleep quality, and objective measures. Often people believe that they take a long time to fall asleep (poor sleep onset latency), or spend a lot of time awake during the night, when in fact this time awake is much less than it feels. Conversely there are others who actually sleep a lot less, but subjectively don’t experience insomnia. Bizarrely, symptoms of mental fatigue and diminished cognition correlate more strongly with the subjective experience rather than the objective measures, possibly due to some kind of nocebo effect!
Work backwards from the time that you have to be up and away to calculate what time you need to be going to bed.
I.e. if you have to be out of bed by 7am, you want to be aiming for lights out by 22.00.
Engineer Your Own Sunset
The Sunset and Sunrise are truly wonderful phenomena that happen every day (duh!), but unfortunately most of us rarely get the time to fully appreciate them on a regular basis.
In the day-to-day modern life, it’s probably not practical to map your daily routine to the rising and setting of the sun, but it’s certainly worth getting out into nature and doing so once in a while.
What you can do however, is try to emulate the process on your schedule.
If your planned total dark time is to be 22.00 until 07.00, then it’s highly recommended to start dimming the lights from around 21.00. Studies have found that it’s blue light in particular that inhibits melatonin production, so using warmer lights, with yellow and orange tones, like our old friend fire is also a good idea.
It’s also strongly recommended to avoid looking at screens, particularly computer of mobile screens. Though there are applications designed to filter the blue light, it’s probably still better to avoid screens altogether, as these devices are designed to stimulate your brain in a multitude of ways, and simply aren’t conducive to a good night’s sleep.
Talk, listen to music, read a book (or non back-lit E book), or any relaxing activity that you could enjoy by firelight!
Rise and Shine
If your planned wake up time is well after the actual sunrise (as mine often is), you’ll want to invest in some black out blinds or shutters on your windows.
This could also be the case regardless of your schedule if you live in an area with a lot of light pollution at night.
You can then recreate the sunrise using a “Wake-Up Light“. These handy devices recreate the rising of the sun, by gradually increasing their brightness from zero to full over period of 30 minutes.
You also then have the option of a normal alarm tone, radio or natural sounds to help coax you out from under the duvet.
Keep an Alarm (or better two!) as a Backup
Like any technology alarm clocks can be used or abused.
If your alarm is enabling you to sleep only 6 hours a night, dragging you out of REM every morning and leaving you chronically fatigued, this is not good.
Conversely, however, an alarm can actually help you have a better nights sleep.
If you have to be up in the morning, for work or any other important appointment, the anxiety from the fear of sleeping in can actually negatively affect your sleep.
Having a reliable alarm (or two) set to make sure there’s no chance of sleeping in will remove this stress, thus helping you sleep.
The key, however to ensure you are getting enough sleep on a regular basis (presuming that this is a regular early start), is to plan your 9 hours of TDT so that you awake naturally before the alarm goes off.
This way, the alarm works as an emergency back up. Providing all goes to plan, you’ll already be awake making the morning brew before the bells start tolling.
Stick to a Routine – More or Less
The research is clear, that the closer you can stick to a regular sleep schedule, the better it is for your overall sleep quality, and therefore overall physical and mental health.
That said, the whole focus of this blog is about living life to the full, and enjoying your time on this planet right now.
Health, wellbeing and longevity are all very important goals, but if you’re going to bed at 22.00 every single night of the week including Friday and Saturday, it’s quite possible you need to do some re-evaluation…
Shortening and shifting a bit later a couple of nights per week in exchange for good times with good friends is at worst (IMHO) going to equilibriate matters, if not pay a net benefit.
Other Bits and Pieces
Routine and Total Dark Time are the big fish when it comes to sleep hygiene.
Some other things to consider however, particularly if you struggle getting a good nights Zs.
- Don’t Eat Too Late
Try to have your last meal at least an hour before you plan to go to bed. - Don’t Drink Caffeine Late
Late is going to depend upon your planned bed time, but probably best to have the last one at least 6 hours before you plan to sleep. Even if it doesn’t stop you dropping off, it may still be degrading the quality of your shut-eye. - Don’t Drink Too Much Alcohol
Though it is a depressant and can help induce sleep, alcohol disrupts sleep maintenance – causing you to sleep less deeply and making you more prone to wake in the night. (Check my updated guide to recommended alcohol intake here). - Stay Cool
The optimum temperature range for a good nights sleep is between 15-19C.
Sleep Well!
Hopefully you found these tips useful. If you try any of them, or have any of your own, please let me know in the comments below!