Science-backed ways to optimise rest and productivity.
It started with a feeling of being scattered and unfocused.
Waking up in the morning and struggling to be productive. Sitting at my desk and drawing a blank. Having a mountain of work to do and yet feeling like there’s no start or finish line. It was like going into a library to find a book I needed, but the library decided to change the ordering system by replacing the librarians with monkies.
And I’m a fixer, I try to find the root cause of the issue, but alas, I couldn’t find the monkies, not until I changed my approach.
I was searching for productivity hacks, focusing tricks, and articles on re-wiring my mindset, but the truth was in front of me the whole time.
It was biology, my most hated subject in school, and yet here it was, ready to save my ass — and who would have thought that sleep was the savior?
I went down a deep dark rabbit hole for mental clarity and focus, but instead, uncovered an ancient system that I had no idea existed — a discovery for me, but likely a welcome reminder for others.
The All-Governing Cycle
It turns out that this robust set of rules turned from habit to physiological trait because of the nature of our planet — the cyclical rise and fall of the sun, and with it, light and temperature.
And the reason why that system, or cycle, is so powerful lies in its age — 70,000 years old — or in other words, as early as the cognitive revolution.
The system is a collection of circadian rhythms, and you might remember it from elementary school as the ‘body clock’.
It’s matched to the natural day/light cycle that runs over 24 hours and regulates what hormones to release and when, the perfect time to be alert, and what the metabolism should do when you eat a doughnut.
And in my quest for mental clarity and focus, I found that sleep was a massive factor in this biological machine, it dictated nearly everything I was looking for, it was the foundation.
I found that the amount of sleep we get or lose through the night is controlled by these mental and physical systems that are operating 24/7.
To take control of my scattered and unfocused mental state meant I needed to work within this cycle and fix my sleep — and only then could I fix my attention and stressful state of mind.
And it wasn’t as complicated as it sounded, because right about now, you might be thinking what I was:
“Is this really the thing? Is there not an easy productivity tip that I can follow instead?”
And to that, I’d say, oh good sir or madam; this is the genius in the cycle — working within it comes so naturally that a few small changes will put you on the right side of evolutionary habits. And hopefully, put you to sleep as well.
Melatonin and The Clock
‘I love sleep. My life has the tendency to fall apart when I’m awake, you know?’ — Ernest Hemmingway
There are so many ways of looking at this quote, but I’m going to hijack it to suit my narrative. If you’re awake and your life’s falling apart, maybe your sleep isn’t so great? Perhaps you need to up your melatonin game.
And this was precisely my problem. I thought I slept well, but what I didn’t realize was that my frame of reference was based on subpar sleep. And it turns out that optimizing my melatonin would increase the quality of the sleep — it all starts with understanding how the cycle works.
The body clock we mentioned earlier takes the form of a small place in our brain’s hypothalamus. It’s a cluster of nuclei called the suprachiasmatic nucleus or SCN — this is all just fancy science speak for body clock.
The SCN is above our optic nerve, and the optic nerve is the thing that sends information from our eyes to our brain.
Essentially, the phrase “eyes are a window into the soul” is passable here, because the body clock, although having many queues we’re going to talk about soon, has a primary queue, and that’s lightness and darkness.
And light, along with heat, exercise, and more fun things like and or caffeine all come together to induce melatonin production among other hormones. Optimizing what we do in these domains unlocks a sweet and sound slumber.
To unlock the door to better sleep, we should start with the main cue — light.
Here are two main takeaways before we go into light exposure.
- Artificial light = bad for sleep
- Natural light = good for sleep
Artificial light exposure suppresses melatonin, especially when it’s absorbed at a time when the sun is down, and its getting closer to the cycle’s natural schedule.
So your laptop, phone, and lamp will put off your body’s natural clock the longer they’re on, which we all know is a modern-day problem. Suddenly the camping phenomenon makes perfect sense — where seven in the evening feels like midnight, and we’re up and running at sunrise.
Our body has evolved with queues for light, and thousands of years of being bound to a planetary day/night cycle means the great outdoors, and the sunlight is the key to better sleep.
And suddenly, all those productivity tips people regurgitate have some scientific backing.
- Sunlight and being outdoors during the day decreases the likelihood of sleep interruptions from light, at night.
- Keeping your room dark will contribute to melatonin production — so blackout curtains are big yes.
- Switching off your screens and light sources in the evening, especially a few hours before bed, will sync you up with the body clock.
- Sleeping earlier is, evolutionarily speaking, the most natural state.
Moving on from sunlight and the outdoors, let’s talk about another killer combo.
Heat and Exercise
How often do you think about the heat in the context of mental clarity? Even concerning sleep, I’m either too hot or too cold; otherwise, I’m not thinking about it.
And yet, heat’s a massive regulator for sleep. The circadian rhythms we experience in a day naturally push our body temperature to the highest point later in the evening, this is a preparatory response by the body — it’s saying “grab that pillow over there, please.”
Once you’ve reached the peak, you start to cool off, and this is when melatonin production begins. In fact, after light, your room temperature might be the most critical factor in putting you to bed.
- 18°C to 19°C or 65°F is the ideal sleep-promoting temperature.
- Extra heat will affect your sleep, both REM and SWS, as it doesn’t sync with the SCN schedule of cooling, but the cold won’t have an effect.
Another thing that peaks our core temperature is exercise, and once we stop, the cooling process begins — queue another queue.
Exercising in the evening and then sleeping a couple of hours after means that you’re already in the process of winding down — and it’s a double whammy, by the way.
Endurance or aerobic exercises also promote a whole host of things that not only directly clear your mind and reduce mental clutter, but also take away from the friction associated with sleep.
- It reduces cortisol production, aka — the stress hormone. Decreased cortisol means increased melatonin.
- Aerobic exercises promote better impulse control, working memory, and higher antidepressant and euphoriant production.
- Studies have shown that adopting a regular exercise routine independent of an evening workout has helped people with insomnia.
And if you nail exercises and optimal heat, along with the primary queue of light — you can stop right here. Your sleep is no doubt going to improve, and your mental clarity will go through the roof.
But there’s one more piece of the puzzle for the urban human, and this one was a biggie for me.
You won’t be surprised when I say coffee boosts your awareness and focus, and you’ll have a similar reaction when I say that drinking it later in the day will mess with your sleep.
Yes, both very obvious, but how much is too much? And how late is too late?
A study in caffeine’s effect on sleep showed that 200–400mg of it, up to 6 hours before rest blocks neurotransmitters and effectively makes you lose an hour of sleep — and on top of that, it rudely reduces the quality too.
But you don’t have to throw out the beans; on the contrary, there’s a perfect solution.
Restricting caffeine to the mornings and not going over a cup or two will align the benefits of increased fat breakdown, concentration, and memory, with the peak awareness and metabolism that the body clock offers.
Figuring that out was a joy — not only was my sleep going to get better, but optimizing my coffee intake was going to reduce my mental clutter and help with concentration, just like I originally wanted.
I found it funny that the original productivity tips I was looking for to gain that sweet sweet mental clarity got tossed to the side and made its way back to me like a boomerang.
Going down to a biological foundation allowed me to compile all these new findings into my own set of tips.
Tips that I can now pass off to you, so if you’re going to recount one story that you can tell yourself to remember all of this, here’s the simple version.
- 🕑 Making it easy for our body to do its 24-hour cycle is the quickest way to feel mentally fantastic.
- 🛏️ Sleep is a cornerstone of that 24-hour biological cycle.
- 🌞 Promoting sleep means getting enough natural light during the day and restricting artificial light at night.
- 😴 Making sure you do enough cardio during the day, and optimizing your room to 18°C or 65°F is a great way to boost the Zs.
- ☕ Restricting coffee to the mornings, and not going overboard will give you the best of both worlds.