It’s been a week or so since I’ve gone on PTO, and in my usual fashion I’ve spent a big chunk of it replicating the sleeping pattern of a cat - simply catching up on sleep. I’ve never had a great relationship with sleeping, mostly lack thereof, but I always loved a good long nap which probably wouldn’t even classify as one due to its length.
But why is sleep so important, should you nap, and is catching up on asleep actually possible?
There’s a great book on sleep called “Why We Sleep” by Matthew Walker, that explains the science behind sleep, its impact, and dangers of it being limited. Our bodies operate in a 24-hr internal clock, called the circadian rhythm, this is what regulates our awakeness and sleepiness based on the environment’s light. Simply we are governed by the Earth’s 24-hr rotation around its axis.
Melatonin, aka the sleepiness hormone, is produced by our body in the response of darkness (lack of sunlight). It starts increasing in our body after 6pm (sunset time) and peaks between 2 and 4am, and then gradually starts falling, as shown in the graph below. The way this hormone works is that it attaches to certain receptors which help you relax and hence fall asleep.
Sleep Stages
Now once you’re sleeping there’s different stages of sleep which are of importance for different brain and body functions. There’s five stages that can be grouped into two main ones, REM and non-REM sleep, where REM stands for Rapid Eye Movement.
Wake, N1, N2, N3, and REM are the five stages, with about 75% is spent on the Non-REM stages, and overall the most in the N2. Each stage is deeper sleep starting from N1 till REM as the diagram below shows. REM is where dreams occur.
A complete sleep cycle takes about 90 to 110 mins, so on average we have 5 of those cycles per full nights sleep - assuming an ideal 8 hr sleep.
Sleep & Disease
Lack of sleep has been linked to many health issues and diseases, from cancer, to heart disease, metabolic disease (you may have noticed you’re hungrier when you’ve not slept a lot), and even Alzheimer’s. Sleep is vital for our immunity, proper endocrine regulation (our hormones), metabolic control, and mental health. Sleep has a direct effect on memory, creativity, decision making, and emotional regulation - being deprived of it impairs both the cognitive abilities as well as the emotional state. A huge issue is the link between little sleep and inflammation, as outlined by Irwin et al. in his study, high and chronic inflammation is the reason for multiple diseases and ageing by definition. Now, ageing is linked with impaired vascular function which is associated with many diseases, like, cardiovascular disease, hypertension, kidney disease, neurodegenerative (like Alzheimer’s), frailty (increased fall risk), and even strokes.
Sleep Mentality
Unfortunately, in the western world, there is a huge shift of doing so much during the day (hustle culture) and minimal sleep is praised and seen as a metric of achieving more. Trends of mega-entrepreneurs starting their day at 4 am, doing everything and anything and just getting couple of hours of sleep is idealised and seen as remarkable. In reality, this is truly having an impact on their health both short- and long-term, and most likely having had a bit more sleep would actually make them more productive and efficient due to better cognitive abilities without being ultra-dependent on energy boosters like caffeine & more…
Sleep Quality
Outside of working long hours, or being up late out, there’s many other factors that actually affect both our ability to sleep and its quality.
High caffeine intake, especially past noon, considering its half life is 6 hrs or so, this means if you have a coffee at 6pm by midnight you would still have a considerable amount of caffeine flowing through your body.
Blue light disrupts our natural circadian rhythm and reduces the amount of melatonin our body releases, so being on our phone or watching netflix prior to bed does more harm than good.
Alcohol is known to be a sedative, however, due to its nature it also dehydrates you and causes you to have less deep sleep - it also tends to lead to day time sleepiness the next day.
The most obvious which is stress - this mean higher cortisol in our body, which simply means it takes longer to fall asleep but also fragmented sleep.
A factor not very well known is the air quality in your bedroom, rooms high in CO2 lead to worse sleep and not feeling as refreshed when you wake up - this is why sleeping with a window open is advised in order to circulate the air. If you think about it you’re in that room for many consecutive hours most likely with the door closed too.
Naturally, our body temperature drops as bedtime approaches, so a room that is very warm will lead to poorer sleep as it interferes with the body’s thermoregulation. It also means less time spent in deep and REM sleep. So, combining it with the above and having a window open also ensures a better room temp.
If you’ve read “Breath” by James Nestor you know how bad mouth breathing is, well this also holds for when you’re asleep, nose breathing is the ideal. This also means less snoring and reduced chance of sleep apnea as the tongue is correctly positioned within the mouth. Mouth taping is an excellent (tried & tested) way of teaching your body how to breath through your nose instead.
Consistency is vital, the body works as a clock so going to bed one day at 10pm and the other at 3am messes again with the hormone regulation and melatonin production, you’re unable to go into consistent sleep cycles that are long enough.
Napping
Considering the last point I made, it sounds a bit stupid and harmless having a nap during the day as that surely would disrupt the sleep cycle. But culturally, esp in the Mediterranean and Middle East area, naps have been ingrained since forever. Back home (Greece that is), during the summer after your morning spent at the beach, which is followed by lunch of course, everyone goes away and has a nap / lies down. The rest of the year, even shops are closed during lunch time so people can go home have lunch and rest. Many islands in Greece and Italy, which still to this day follow this routine and are not behind a screen from 9 to 5 at best (soft slavery), have the highest life expectancy but also with high quality lives and low disease.
That being said there’s also a right way of doing naps, the cut off time is 3 pm, any sleeping post that disrupts your night sleep - guaranteed! Early afternoon is ideal, as this won’t effect the melatonin production which will come into effect is the early evening. They should also be short, 20 - 30 minutes is advised, this won’t put you into deep sleep, so when you wake up you will feel refreshed and not super snoozy afterwards. Ofc you will need some time to ‘re-wake-up’ once the nap is done, so do account for that as well. If you’ve not slept enough the night before, having a nap can be v good, and give you a rush of energy that you wouldn’t have had before without taking caffeine or consuming something high sugar to get you going. As said earlier, a full sleep cycle is around 1.5 hrs, so if you’re in need of a longer nap as you’ve truly not slept a lot, trying to match the nap with the sleep cycle would ensure adequate rest and proper wake up times.
What I used to do (not sure I’d 100% recommend) is a coffee nap, what you do is you have an espresso or a coffee and go lie down to nap, so by the time you’re done with the nap you’ve also gotten the caffeine hit so you would get more energy that doing either solely. This happens as you increase your brain’s capacity to receive the caffeine.
Sleep Debt
Sleep debt, is the sleep you’ve not actually gotten but needed. There’s been a notion of catching up on sleep and making up for the missed sleep (a self-proclaimed expert in this field, been practising this for years). That being said, long term sleep deficit makes it much harder to catch up on sleep due to the prolonged amount being missed. If you’ve ever been burnt out you know that regardless of how much sleep you get you still feel as tired, this also has to do with the cortisol messing you up as it drops way too low (a whole other post is required for cortisol!). This is also the reason when you work so much and are so addicted to it, the moment you go on vacation you get sick or don’t feel well as suddenly your whole environment and hormones have changed - in a very simplistic explanation.
To conclude, these holidays please give yourself one of the most important gifts of adequate sleep - as tempting as it is to be up late with friends, family, and loved ones, the chance is now for catching up on some sleep and resting ahead for the new year. You may even find that you’ll be more productive and have greater ideas for when you resume to work. So be a bit more greek, act like it’s a Sunday and nap away!
As usual, I have added some links below. I hope you enjoyed - See you next week! :)
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