This is how your sleep is affected by what you do during the day

Independent

24-02-2025

If you're struggling to sleep, the key to your insomnia may be hidden within your daily routine.
What you do – or don't do – during the day can have a profound effect on your sleep at night, explains psychotherapist and sleep expert Heather Darwall-Smith.
'We often think of sleep problems as something that starts when we get into bed, but in reality, how we live during the day plays a huge role in how well we sleep at night,' she says.
'If you're lying awake at 3am staring at the ceiling, trying to will yourself into sleep, stop fighting. Sleep isn't something you can force.'
Darwall-Smith, whose new book How To Be Awake is about to be published, explains that sleep involves two processes – firstly, your circadian rhythm, the internal body clock that tells you when to feel awake and sleepy based on light, movement and routine, and secondly your homeostatic sleep pressure. This is linked to a chemical called adenosine, which builds in your brain from when you wake, increasing your need for sleep.
'The longer you're awake and active, the stronger this sleep pressure becomes,' she says. 'At night, high adenosine levels help you fall asleep naturally.
'Both processes work together across the 24 hours of the day and night to open a window for sleep. If you haven't built enough sleep pressure or your body clock is out of sync, sleep can feel elusive no matter how much you want it.'
In addition, our relationships help shape our nervous system and can also impact sleep, she explains. 'A difficult conversation, unresolved tension, or feeling unseen can all follow us into the night,' she says.
'So instead of obsessing over how to sleep better, flip it on its head to think: How can I be awake in a way that makes sleep happen naturally?'
Here's her advice on how to do it…
1. Get up at the same time every day
Darwall-Smith explains that your body clock thrives on consistency, so when wake-up time shifts – sleeping in after a restless night or waking early some days and late on others – it throws off the entire sleep-wake cycle. A stable morning wake time sets the timing for sleep pressure to build correctly, so by evening your body is naturally ready to rest.
'If you only change one thing to improve your sleep, let it be this,' she advises. 'This single habit anchors your circadian rhythm, reinforcing when you should feel awake and when your body should start winding down for sleep.'
To help achieve such consistency, she suggests sticking to a regular wake-up time – weekends included; exposing yourself to daylight as soon as possible (this tells your brain it's time to be awake); and resisting the urge to make up for lost sleep, as extra time in bed can weaken sleep pressure, making the next night harder.
2. Start the day mindfully
How you wake up shapes how you sleep, so if you wake to a blaring alarm and then scroll through your phone before getting up, the first thing your body experiences each morning is a stress response, and you're setting yourself up for a day of stress and a night of restless sleep, warns Darwall-Smith.
'Your circadian rhythm relies on clear signals in the morning – consistent timing, light exposure, and movement all anchor this process to work in tandem with signals 12-14 hours later that start the countdown to sleep,' she explains.
As well as getting up at the same time every day, she recommends stepping outside or sitting by a window as soon as possible, as morning light anchors your body clock.
Swap your alarm for a sunrise clock, or set a gentler tone that doesn't make your heart race, and do your best not to feel rushed.
She explains: 'Slowing down – taking time for breakfast, moving with intention, and starting the day mindfully – reduces stress. A calmer morning sets the tone for a more balanced day, which supports better sleep at night.'
3. Give your brain a break
If you fill every moment of the day with tasks and constant input, your brain won't get the chance to slow down. So at bedtime, instead of resting, your mind goes into cognitive overload and will process everything at once – rehashing conversations, unfinished tasks and old worries.
To avoid this, Darwall-Smith advises taking real breaks during the day, where there's no scrolling and no filling every spare moment. Give your mind room to wander by daydreaming, staring out of the window, going for a short walk without your phone, and creating 'mental off-ramps' where you downshift by dimming the lights, reading, stretching, or listening to something soothing.
'When you allow moments of mental white space during the day, your brain won't ambush you with thoughts at night,' she promises.
4. Make day different to night
If you've spent all day sitting still and scrolling, your body might not feel ready to sleep, Darwall-Smith points out. 'Sleep happens when there's a clear difference between wakefulness and rest – but if you've been in a low-energy, low-movement state all day, there's no strong contrast,' she explains.
But you don't have to do vigorous exercise to create day and night contrast – Darwall-Smith says research shows small movements – fidgeting, stretching, shifting in your seat – help regulate your body clock and sleep pressure.
So she advises standing up every hour, even if it's just to stretch, walking or moving while you talk on phone calls and in meetings, and embracing fidgeting – 'It's your body's way of keeping itself engaged,' she says.
5. Acknowledge unprocessed emotions
Unresolved emotions don't just vanish when you close your eyes, and insomnia can be the result, says Darwall-Smith.
She says it's important to shake off tension, do a few deep breaths, let your system know it's OK to relax, and create a ritual that says the day's over, with a warm drink and dim lighting. 'Acknowledge what's there,' she advises. 'You don't need to solve everything before bed, but finding ways to name and process this helps.'
5. Settle yourself
If you're feeling emotionally or physically unsettled, you'll remain on high alert, Darwall-Smith warns. 'A nervous system stuck in alert mode doesn't prioritise sleep,' she stresses.
Acknowledge what's making you feel uneasy and use deep breathing, weighted blankets and grounding exercises to help you feel safer, she suggests.
6. Don't chase sleep
Darwall-Smith points out the harder you try to control sleep, the more elusive it becomes. So she suggests ditching your sleep tracker if it's stressing you out, letting go of any rigid rules about your bedtime routine, and shifting the focus to your waking hours.
'Hyper-focusing on sleep can turn it into a performance when it's meant to be a natural, unconscious process,' she says.
'Instead of trying to fix sleep, try being awake in a way that lets sleep happen naturally. Sleep isn't the goal – living in a way that invites rest is.'
But she stresses that if you consistently struggle with sleep despite making changes, you may have a sleep disorder and it's worth speaking to a healthcare professional. 'If sleep feels like a battle every night, you don't have to figure it out alone – help is available,' she says.
How To Be Awake (So You Can Sleep Through The Night) by Heather Darwall-Smith is published by Harper NonFiction on February 27, priced £16.99.