A sleep expert answers all our questions on the different sleep stages, why they’re important & how to make them count for a more restful night’s slumber
Picture it now. You’ve woken up bright and early. The birds are singing and the sun streams golden through your window. You sit up and stretch. You’re well rested, energised and rejuvenated – and all before you’ve even made a cuppa. Today will be a good day. Why? Because you had a great night’s sleep.
The transformative power of some proper shut-eye isn’t to be sniffed at, but for many of us, this dreamy morning scenario really does feel out of reach. While most adults need around eight hours of sleep each night, according to the NHS, one in three of us suffer from a lack of it, with the stress of the last couple of years, computers and taking work home with us (we’ve all been there) all playing a role. The encouraging news though is that there are ways to recalibrate our sleep patterns and get back into healthier habits.
A good starting point? Understanding our sleep cycle and why each of its stages are so important. We asked James Wilson, aka The Sleep Geek, sleep expert and co-founder of Beingwell website www.thesleepgeek.co.uk, to break it down for us to help get us back on track.
What is the sleep cycle?
Our night’s sleep is made up of not one, but several sleep cycles. "Each round lasts about 90 minutes, although it could be as little as 70 minutes and as much as 120 minutes," explains James. "It’s this cycle that includes the different stages of sleep within it. During a single night’s sleep, we’ll come out of these cycles four to six times on average."
What are the different stages of sleep?
Every sleep cycle is made up of four sleep stages, three that form non-rapid eye movement (NREM sleep) and one for rapid eye movement (REM sleep). NREM sleep can be classified as stages one-three, while REM sleep is stage four.
Let’s get down to what happens to the brain and body during each one…
Stage one (N1)
"This stage is where we’re dropping off to sleep and everything is slowing down," says James. "Your brain and body will start to relax and unwind, while your heartbeat, eye movement and breathing will slow too. At this point it’s not unusual to wake with a start as your muscles twitch." That falling feeling that wakes you up with a jolt just before you nod off? Nope you’ve not just fallen down a flight of stairs, you’re just likely to be in stage one of the sleep cycle.
Stage two (N2)
"The second stage is where our body starts to drop further into sleep and we become less aware of our surroundings," James explains. "Other changes include a drop in our core temperature, eye movement stopping, our brain waves slowing, as well as our breathing and heart rate becoming more regular.
Stage three (N3)
"The third stage of sleep is known as deep sleep or slow wave sleep and is the most important for physical recovery," explains James. "It’s at this point growth hormones are produced which are important when it comes to keeping our immune system healthy." Ever woken from a nap feeling groggy or experienced night terrors? "Chances are you’ll be in stage three," says James. "Your muscles are completely relaxed, your blood pressure has dropped, and your breathing has slowed, making it extremely hard to wake someone who has progressed into this stage.
Stage four (REM Sleep)
During REM sleep your brain lights up with activity, your body’s relaxed, your breathing moves faster and more irregularly and your eyes move rapidly behind closed eyelids. "Think of REM sleep as being where we consolidate memories and knowledge from the previous day, putting them into the right category within our brain's filing system," James says. "I always view this stage as the one where we build emotional resilience. Think of it as an overnight counselling session, where our mind works through the emotions of the previous day."
How long does each stage last?
"Everyone is different," says James, "but the below is a general guide."
Stage one: Five minutes
Stage two: 10-25 minutes
Stage three: 20-40 minutes
REM: A few minutes to an hour
At what stage might dreaming occur?
Most of our dreaming occurs during REM sleep, although some can also occur in the other stages. "It’s during REM sleep that we’re more likely to remember our dreams," explains James. "This is because we’re easier to wake at this point." But what stops us from actually acting out these dreams? "During REM Sleep our muscles are temporarily paralysed to stop us from doing this," says James. "But in some people, this doesn’t filter through, causing parasomnias like sleep walking. On the other end of the spectrum, there’s sleep paralysis, where part of the brain wakes up but we’re unable to move."
So, why do sleep stages matter?
We all know the bleary, unfocused feeling that comes alongside too little sleep, but do the sleep stages themselves really matter? The short answer? Yes.
"Sleep is our number one recovery tool," says James. "We should never underestimate its importance. Just by looking at the sleep stages we can see the significance of the sleep cycle as a whole being fundamental to our physical and emotional recovery. If we’re not getting the amount of sleep we need, it usually has a significant impact on the REM stage, as we get the majority of this later in the cycle. It’s REM sleep, alongside stage three sleep in particular, that can really increase wellbeing."
Indeed, it’s worth being aware of some of the health risks a lack of sleep can cause.
What can affect the quality of our sleep cycle?
There are an array of factors that could affect the quality of your sleep cycle, but here’s a few of the main reasons below:
Anxiety, depression & stress: It’s important to realise that anxiety, depression and stress can affect the quality of the sleep cycle. It’s always worth seeing your GP if you think you could be affected. Read more about the link between sleep and depression here.
Alcohol, caffeine & nicotine: These can all interrupt sleep, so try to avoid them too close to bedtime.
Daytime naps: If you are napping, limit short bursts of slumber to 20-30 minutes.
Exercise: The benefits of exercise are undeniable when it comes to sleeping better, but up your heart rate too close to bedtime and you’ll be left struggling to snooze.
Screen time: Scrolling through TikTok (guilty) can overstimulate the mind before bed.
How can we learn from our sleep stages to improve our sleep quality?
"When it comes to improving your sleep hygiene, I would say don’t focus on improving your stages individually, but your sleep cycle overall," advises James. Consider the below factors that could maximise your chances of a great sleep cycle, and ultimately, a great night of shut-eye.
Get light exposure in the day: Exposing your body to natural light can help maintain a healthy circadian rhythm.
Wake at regular times: This programmes the brain and internal body clock to get used to a set routine.
Create a comfortable bedroom environment: Investing in quality bedding and lighting can make for a relaxing space to sleep.
Wind down: Yoga, reading, and warm baths can all act as great ways to aid slumber. Try this yoga nidra practice before bed.
If you can’t sleep: There’s no worse feeling than watching the clock when you’ve woken up during the night, however a certain amount of waking up during the night is normal. Avoid the temptation to do anything that may overstimulate your senses – activities like checking your phone will only wake you up more. Some may find it useful to read a book to feel sleepy again, but simply resting may help too.
The takeaway here? Sleep is vital when it comes to our health and wellness. And for those struggling it’s good news – it’s never too late to regain control of your sleeping habits and increase the quality of your cycle in the long term. In the meantime, follow our recommended steps to help improve your sleep quality or book an appointment with your GP for extra support. Sweet dreams…