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Sleep has a profound impact on both your physical and mental health. By understanding the physiology of sleep—how sleep and wake works in the brain—I hope that it'll help you to build better sleep habits.
I've found that changing my alarm clock, my coffee timings, my relationship with blue light and more closely tracking my sleep has helped me to improve my sleep. Here's how.
7am: Lumi Light
Shocking yourself awake with a screaming alarm clock is never healthy. You end up snoozing it and then feeling wiped out in the morning.
Rather than getting woken up by sound, I chose light instead. I got a Lumi light to see if it was a better way to wake up—using a light that emulates a sunrise, rather than a sound that emulates a fire alarm. Why is it better?
Being exposed to bright light in the morning helps set your circadian rhythm; your master sleep clock that works in a 24-hour cycle. It tells your brain when to switch on and off. The same sleep clock that keeps you up when you’re jet lagged. The bright light will help you to feel more alert in the morning, and help you feel sleepier in the evening.
Personally, it gives me a bit of a warning because I notice the light while I’m still asleep so then when the alarm goes off, I’m way less surprised, and way less groggy when I’m waking up.
9am: Track your Sleep
By tracking my sleep more precisely, I've been able to see how different habits affect the quality of my sleep.
To do this, I got a Whoop fitness band. It allows me to track my sleep. It doesn't just tell you the hours, but breaks it down into the different stages of sleep.
They are: Wake, light sleep, slow wave sleep, and rapid eye movement (REM) sleep. It's useful to know the difference between these because slow wave sleep is time for repair and growth of your muscles, helping your recovery from leg day or your sprint for the train. REM sleep is dream sleep, those dreams can be helpful for emotional processing and it’s important in consolidating memories and learning.
3pm: Control your Coffee Intake
In the past, I’ve ended up having buckets of coffee late in the afternoon. The issue: when I get in bed I'm wide awake.
Our brain uses energy in the form of adenosine triphosphate (or ATP), once it’s been used it leaves adenosine behind. While ATP gives us energy, adenosine lets our brains know we need to chill. It’s a clever system because the more we use, the more we're signalled for rest.
Caffeine jumps in and blocks adenosine—sending you into overdrive. Caffeine has a half life of about 6 hours, so the concentration in your blood will half in that time. By stopping your caffeine intake after about 3pm, you allow time for it to break down and shift out of adenosine's way. With space to do its job, adenosine can then tell you it's time to sleep.
8pm: Reduce your Blue Light Exposure
I'm sure you're aware of blue light by now. Every man and his dog talks about it but I want to explain why it affects you, and share a couple of tools I’ve found useful.
We’ve addressed how adenosine tells us to sleep, but there’s another key messenger that also makes us sleepy: melatonin. Remember the circadian rhythm? Melatonin does the groundwork for the master sleep clock. Just like exposing yourself to bright light in the morning wakes you up, if you do it at night it has the same effect.
But bright lights aren’t all equal. A Harvard study showed blue light suppressed melatonin for about twice as long as green light and shifted circadian rhythms by twice as much.
Here are a few steps to reduce it:
- Turn down the brightness of your displays. It isn't just blue light, but bright blue light that's the issue.
- Set your display to a warmer temperature at night.
- Wear blue light blocking glasses. While I try to avoid working late at night, when I do I wanted to minimise the effect of the blue light by filtering it out.
I’ve found these steps together allow me to be productive at night on my laptop or phone, while keeping the melatonin flowing.
10pm: Reading Before Bed
This one's more anecdotal rather than evidence-based. I read every night before bed. I’ve been getting more into fiction before bed recently, with my latest book being The Adventures of Sherlock Holmes.
I find it very relaxing. It takes me away from using my phone before I sleep and relaxes me completely. When it hits the bedside table, I'm straight off to sleep.