The Sleep Habit
Sleep is a habit. Get into a good habit and your sleep will be good.
This fact translates into just one hard and fast rule:
Get out of bed within 30 minutes of the same time everyday. Every day.
That includes the weekend. This will make your body rhythms consistent and you will get good at sleeping the whole time you are in bed because your body will know that that is the time allocated to it for sleeping.
Equally this will mean that you will begin to feel tired around 8 hours before your wake up time. So go to bed then. Don’t fight your body.
It is a scientific fact that most people get most benefit out of sleeping the hours between 11pm and 7am. Don’t blame me if you like staying up later, I’m just saying.
And that’s pretty much all there is to it. However, there are some things that contribute to sleep, some things you can do to facilitate it and some things that you should avoid. These tips are called Sleep Hygiene.
1. Don’t use your bed (or bedroom if possible) for anything other than sleep. Your body will then get used to the equation Bed = Sleep and respond accordingly.
2. Read fiction before sleeping. This activates the right side of the brain and helps you switch off the hyperactive, analytical left side. This will particularly help you if you spend hours lying in bed thinking over problems and worrying about things. Whatever you do, do not read non-fiction. This will have the reverse effect and you brain will churn over the ideas all night.
3. Don’t take caffeine after lunch. Caffeine is a stimulant and takes around five hours to leave the body. Caffeine includes coffee, coke and chocolate.
4. Don’t drink alcohol either. It badly damages sleep quality. Have a drink at lunch time instead!
5. Don’t smoke. Nicotine is a stimulant and smokers get withdrawal symptoms during the night, disrupting sleep.
6. Get a bigger bed. Sleep is an activity. During the night we twist and turn – as shown by the state of the bedsheets in the morning! If you sleep with someone else then consider a king size. Seriously, people who sleep together, sleep worse.
7. Sleep in silence. If noise is a problem, then use earplugs or a white noise recording (you can find them on the internet or just detune a radio). A fan works as well, although you might dream that you’re flying through the wind.
8. Keep cool. Body temperature is crucial for sleep and therefore so is room temperature. Slightly cool works best. Make sure there is sufficient ventilation as well.
9. Don’t eat a meal in the three hours before your sleep time. But you could have a small snack high in tryptophan, calcium and carbohydrate like a roast turkey sandwich with a small glass of warm milk. Tryptophan promotes sleepiness, calcium facilitates the absorption of tryptophan and carbohydrates slow and clear the mind. Avoid proteins at all costs.
10. Avoid bright lights in the run up to bed time. Your body clock is set by daylight, so you’re just confusing it with bright electric lights. Dim the lights, or read with just a soft table lamp. Equally, eliminate light in the room when you are actually trying to sleep. You might have to use blackout curtains or a eye mask.
11. Listen to an audio book to help soothe you to sleep. I know someone who listened to a recording of Marcel Proust’s ‘Swann’s Way’ for a whole week and never got past the first few pages. However, put the player on a timer so that it doesn’t wake you up a few hours later.
12. Take a warm bath before going to bed. Sleep onset is encouraged by a drop in temperature. A warm (but not hot) bath will simulate this drop as the water evaporates off your skin. However, this is artificial and not normally necessary. Bear in mind that this artificial drop is followed not long after by a gradual rise in body temperature as you warm up again. This is not conducive to sleep – so jump into bed within 20 minutes after taking the bath.
13. Slow down your heart rate. In other words, try meditation or focus on your breathing. Whatever you do, do not take exercise in the 3 hours before you intend to sleep. This could mean no after work gym sessions.
14. On the other hand, do exercise during the day. As little as 30 minutes exercise will help you sleep at night. Hit the gym in the morning.
15. Do not do any stimulating activities before sleeping. This means television, surfing the internet or card games.
16. Avoid sleeping medicines. There is no substitute for natural sleep. If you are still having problems then make doubly sure you are keeping good, regular sleeping habits and go and see your doctor. Be careful.
Now I shall dig a little deeper into what sleep is and what it does for us.
The Stages of Sleep
Sleep is made up of several different phases:
This lasts around 2-5 minutes. It is distinctive for its Quasi-REM (dreaming without the eye movements), which is not well understood. This is the condition that Thomas Edison induced to help him with breakthroughs in his inventions. He used to sit in an armchair with two steel balls in his hands, resting on the arm rests. When he moved from dozing into deeper sleep, the balls would fall onto the floor and he’d wake up from his dreaming, often with a new idea.
The first stage of ‘proper’ sleep is characterised by a slowing of your heart rate and a drop in body temperature. This explains why these two changes can be used to induce sleep. Stage 2 sleep is important for increasing alertness, promoting motor learning as well as reasoning, planning, language, reflexes and social interaction.
Stages 3 and 4 = Slow wave sleep (SWS)
This is the deepest sleep that we have. If we wake up during this phase (thanks to an alarm or an irate policeman) then we will feel groggy. This is known as sleep inertia and has three solutions: go back to sleep for 20 minutes or so, engage in a physical activity or splash water on your face. During slow wave sleep our bodies stop producing stress hormone and boost our levels of growth hormone. We also metabolise fats, cholesterol and carbohydrates during this phase and our mental neurons stop firing. This phase will clear your mind, repair your body and improve your declarative memory (e.g. “The Fire of London was in 1666”).
Rapid Eye Movement (REM)
REM is the most glamorous phase of sleep, it is the time when we dream most deeply and memorably. Our blood pressure and heart rate go up and we pump 50% more blood to the brain which is firing neurons as if we were fully awake. REM sleep enhances our memories as our brains transfer information from short to long term memory. REM sleep also enhances creativity.
It is not necessarily helpful to give approximate time lengths for the various stages of sleep because they vary a lot according to the human. For example, a male aged 20-29 years will spend about 21% of his sleep time in Slow Wave Sleep, a male aged 40-49 years about 8% and those aged 60-69 will spend just 2% in SWS. However, the average duration of a sleep cycle is about 90-100 minutes. This explains why humans average about 8 hours sleep a night, that is 5 full cycles.
So that’s it. Sleep isn’t a terrifically well-understood area of human activity, given that we spend about a third of our time engaged in the activity, but the tips above are a good start to sleeping well.
This article first appeared on the (now defunct) website, How to be Human. I hope it finds an appreciative audience here.