How to sleep well

I was listening to a podcast last week and the host described sleep as "the best legal performance enhancer in existence" and there is now a huge amount of scientific evidence to suggest that they were absolutely right. Whether it be improving our long-term health and immunity, enhancing our cognitive capabilities or enabling our bodies to reap the benefits of exercise and training, sleep has been shown to play a vital role in all these areas.

Yet, while there are plenty of personal trainers to help us exercise more effectively and a good number of nutritionists to improve our eating habits, when was the last time you came across a sleep coach? Few GPs have the time to offer advice other than in the most severe cases of chronic insomnia, but we all know how much better we perform (and how much nicer we are as human beings!) when we have had a good night's sleep.

So here are my key ingredients to sleeping well.

Aim for 7-8 hours of sleep per night (more for children). Given most of us will spend 20-30 minutes every night either getting to sleep or having mini "wake-ups" during the night, that means total time in bed of 7.5 to 8.5 hours. Start from when you need to wake up the following morning, then work backwards to calculate what time is "lights out" in the evening. Don't expect to sleep all the way through the night in one uninterrupted period - this creates unnecessarily high expectations and can lead to sleep anxiety. In fact, humans generally sleep in phases of around 90 minutes with brief periods of wakefulness in between.

Be wary of those people who claim to be able to get by just fine on 4-5 hours a night. Some of them may just be showing off to underscore their alpha status; others might be able to get by physically on such little sleep but they may be missing out on the REM (rapid-eye movement) phases of sleep that often occur later in the night. These are vital to rebooting the brain, processing the events of the previous day and ensuring that you are operating at full mental and creative capacity the following day.

Be consistent. Try to go to sleep at around the same time each night (+/- 30 minutes is fine), including at weekends if you can. Doing so allows the body to get into a good circadian rhythm (its natural daily cycle of ebbing between wakefulness and sleepiness) and start producing melatonin (the sleep-inducing hormone) in the couple of hours leading up to your bedtime. This will help you to fall asleep more quickly and spend longer in the deeper, restorative phases of sleep in the course of the night.

Get a sleep tracker. I started using a Whoop strap a few months ago - it goes on your wrist and uses sensors to monitor your sleep, heart rate, breathing rate etc. The hardware is pretty basic but the app gives a very clear summary of how long you slept each night and the time spent in the various stages of sleep. It can then nudge you if you are getting less sleep than needed given your age, activity levels etc and suggest what time you should be going to bed.

The Oura ring works in a similar way and several people have said to me they prefer it because it is less obtrusive than the Whoop strap - the main difference is that Whoop charges a smaller amount for the hardware then you pay for a rolling subscription, whereas Oura is a larger one-off purchase. It sounds like the next software update for the Apple Watch will incorporate some form of sleep tracker too - frankly I am surprised that Apple have been so slow in adding in this functionality.

What I like about these trackers is that they collate your sleep data without you having to do anything. The traditional approach involves keeping a sleep diary on a sheet of paper next to the bed, which most people forget to fill in and which lacks the detailed and precise data from the trackers. The simple fact of being able to see each morning how long you were actually asleep for (and the quality of that sleep) really helps people to focus on their sleep as a key priority in their lives. It also makes it easier to spot how factors such as caffeine intake or alcohol consumption affect your sleep and alter your behaviour accordingly, which brings me neatly on to...

Alcohol ruins your sleep. This is the clearest and most useful takeaway I have had since I started tracking my sleep. I am not a big drinker (albeit like most people I have certainly drunk more regularly during lockdown), but if I have more than one glass of wine during an evening then I can really spot the differences in my sleep metrics: more disturbed sleep, less time spent in REM sleep and, most obviously, a significantly higher resting heart rate. Spot the drinking night in the weekly chart below...

Alcohol should be regarded as a sedative not a sleep aid - it may knock you out quickly but the quality of your sleep will be significantly worse. Given a few drinks are often accompanied by a later night than normal, that is not a good combination if it is happening too often. If you are feeling tired or stressed, then you should definitely enjoy your social nights out as a great antidote, but be wary of that cheeky beer or a couple of glasses of wine at home on a Monday night that can become a sleep-destroying habit.

One way of getting round this is to try an alcohol-free beer or spirit, so that you can get the taste of a satisfying drink without the alcohol. I was scarred for years by trying Kaliber when it first came out but the good news is that alcohol-free beers have improved dramatically in recent times and they are well worth trying out. I discovered Peroni's 0% alcohol Libera version during lockdown and genuinely think it is close enough to the "proper" taste of beer to not feel like you are missing out too much. I have also been impressed with Lucky Saint. The other good news is many of these beers have less than half the calories of their "full-fat" brethren, although some do have annoyingly high sugar levels. My next quest is to find a decent de-alcoholised wine - all suggestions welcome!

Make coffee a morning drink. Caffeine is a stimulant that many of us turn to when we are feeling tired or a need of a pep-up. There is nothing wrong with this per se, but we need to be mindful of how long it can linger in the bloodstream and therefore potentially disrupt our sleep. Caffeine prevents sleep by blocking the adenosine receptors in the brain - it fits neatly into these receptors and prevents adenosine (the neurotransmitter that signals to the brain that the body is tired and in need of rest) from doing what it is supposed to. 

Different people react to caffeine in different ways and some genuinely seem able to drink coffee late at night without any impact on their sleep, but they are the exception rather than the rule. Caffeine has a half-life of around six hours and a quarter-life of roughly 12 hours, so anything drunk after lunchtime can still be in your bloodstream by the time you go to bed. So the safe option is to confine your coffee drinking to the morning (or switch to decaf after lunch), such that most of the caffeine is out of your system by the time you get into bed. This is the best way to avoid that horrible cycle of drinking coffee to keep you going in the afternoon, which then stops from you from sleeping well that night and leads to you drinking even more coffee the next day.

One other thing to keep an eye is that not all coffee is created equal in terms of its caffeine content. According to the USDA, one espresso shot contains around 64mg of caffeine, but a Grande cappuccino from Starbucks will have two shots in it and a Venti has three so you quickly get to some big numbers - the UK's Food Standards Agency recommends up to 400mg of caffeine as safe for adults over the course of a whole day. On top of this, the punch of an espresso shot can vary enormously from one coffee chain to another. Filter and cafetière coffee also have more caffeine in than many people realise (c. 100-150mg per cup compared to 80mg in a can of Red Bull).

Put your phone to sleep by 9pm. Set your screen time settings to block access to any apps you might be tempted to fiddle around with after this time while you are sat on the sofa. Turn off sounds and notifications that might encourage an immediate response even if it is not really required that urgently. Even better, don't keep your phone in your pocket or have it nearby at all - put it out of sight and out of mind and you will soon forget about it. Most importantly of all, never have your phone in your bedroom overnight. Charge it downstairs and buy an old-fashioned alarm clock to wake you up. Or get one of these Lumie body clocks that use a gradually brightening light to awaken you in a more gentle and circadian-friendly fashion, particularly in winter when it is still dark outside.

There are two reasons why I am so insistent on this draconian treatment for phones and other devices. One is that, as more and more people are now aware, the blue light emitted by them inhibits the production of melatonin (the natural hormone that regulates our sleep-wake cycles and helps to induce sleepiness as darkness descends). This can result in people taking longer to fall asleep and there is some evidence to suggest their sleep is more shallow and less restorative as well. Secondly, and just as importantly, reading emails or rage-inducing Twitter posts just before bed is going to fire up your thinking brain just at the point when we want it to be powering down.

Develop a good wind-down routine in the evening. What form this takes will differ for each individual (and I will cover rest & relaxation in more detail in a future article) but obvious candidates in the evening would include the following:

• reading
• watching TV (again be mindful of blue light, but some TVs now come with blue light filters - check Settings/Display on the menu).
• listening to music
• going for a walk
• a hot bath - your body naturally starts to cool down in the late evening and into the night and the cooling down of your body after the bath seems to amplify this particular part of the circadian rhythm. A recent study at the University of Texas found that a hot bath (40C) around 90 minutes before going to sleep was most effective, reducing time to fall asleep by around 10 minutes.
• meditation/mindfulness
• mobility exercises/stretching/foam rolling: this is another topic I will return to soon as I think it is a hugely important antidote to being static all day in meetings and at desks, as well as being actually quite straightforward to make rapid and rewarding gains. I do 10 minutes of mobility work each night before I get into bed and it is a core part of my evening wind-down, alongside reading.

I would also try to eat as early in the evening as you can, so that you aren't going to bed with too full a stomach and you are giving your body as long a fast as possible between dinner and breakfast. Try to get your sport or high-intensity exercise in earlier in the day too rather than leaving until the evening. This may not be viable for some people, but I play football every Wednesday night from 8-9pm and I inevitably get a more disturbed night's sleep after that compared to a normal night. I hope that is not just down to reliving a missed chance or giving away a penalty! The research is not clear on this but there are some suggestions that higher-intensity exercise in the evening can stimulate the nervous system and elevate your heart rate, making it harder to get to sleep.

Make your bedroom as sleep-enhancing as possible: quiet, dark, cool, comfortable. Quiet and dark are obvious criteria for a good sleeping environment. A cooler temperature (around 18C as a guide but most importantly colder than the rest of your house) plays to the earlier point about body temperature dropping in late evening and into the night, coinciding with falling asleep. If you are sharing a bed with someone else, then go for as big a bed as you can manage, in order to give one another sufficient space to move around whilst asleep without disturbing your partner. Equally, what counts as a comfortable bed can vary hugely from one person to another, but it is surely worth investing some time and money in getting this as right for you as possible.

Nick Littlehales, who has worked with a number of top sports teams on improving athlete sleep, goes into considerable detail on beds and bedding in Chapter Six of his book, "Sleep", for those who want to find out more. One very simple point he makes is how much people enjoy the cool, clean feeling of fresh bed linen when they get into bed. We may not be able to go down the British Cycling route of washing and changing their riders' linen every night, but we can perhaps manage shifting from one change per week to two.

Thick curtains, blackout-blinds and triple-glazing can all help improve darkness levels and reduce noise, but these are expensive and it is also worth trying simpler solutions like earplugs and eye masks. The latter don't work for me as I dislike the close feel on my face, but others seem fine and unaffected by this. In terms of noise, we live under the flightpath into Heathrow and, when I was working in the City and sleeping quite lightly and fitfully, I would get woken up by the first flight in every morning around 5.30am - not good! I experimented with all sorts of foam or wax earplugs but always found that they fell out during the night and so were useless by the time they were needed. Eventually I found a pair of unobtrusive in-ear sports earphones that block out a good amount of sound but have little tabs designed to keep them in your ear when running, and that has solved the issue for me.

Sleep well. A good night's sleep will improve your health, mood, fitness and general wellbeing and yet it is something that too few people prioritise as much as they should. The great thing is that none of the above requires huge effort sweating in the gym or a complete change in your eating habits. A bit of thoughtful time management is needed, although the extra hour or two that you may be saving by not commuting into work at the moment helps on that front. And some upfront effort and willpower may be required to break old habits in terms of alcohol and caffeine, for example. But, if the biggest thing I am asking you to do is spend an extra hour in bed, then surely that should not be beyond most people...

Steve Davies spent 25 years working in the City, including more than a decade running a ￡2bn UK equity fund at Jupiter Asset Management and working closely with hundreds of CEOs, CFOs, Chairmen and Board Directors of listed UK companies. He left Jupiter in 2020 to develop a wellbeing coaching programme for CEOs, business leaders and City professionals, covering areas such as sleep, nutrition, exercise, relaxation, time management and concentration skills as well as providing advice and support in their professional roles.

Email [email protected] or call 07956 157172 for more details.