Key findings
Many people who sleep poorly stay mentally and physically 'switched on' at night, and calming that state is a core target of insomnia treatment.
The hyperarousal model holds that insomnia involves raised arousal across cognitive-emotional, cortical (high-frequency EEG) and neuroendocrine systems. A 2023 review found good support for cognitive-emotional and cortical arousal but inconclusive evidence for heart-rate and heart-rate-variability markers.14
Limits Mostly cross-sectional comparisons of people with chronic insomnia versus good sleepers; whether hyperarousal causes insomnia or follows it is not settled. Applies most clearly to chronic insomnia, less to occasional slow nights.
Racing thoughts and worry are the reason people with insomnia most often give for not being able to fall asleep.
In an early survey of people with insomnia, about 55% blamed cognitive arousal alone versus about 5% physical tension. Interview studies (30 sleep-onset insomniacs vs 30 good sleepers) show poor sleepers' pre-sleep thoughts focus more on worries, problems and not sleeping, and feel less controllable.57
Limits Self-attribution data from people with insomnia; there is no population study ranking the causes of slow sleep onset in general, where circadian delay, caffeine and going to bed before sleepy also matter. People with insomnia tend to overestimate how long they take to fall asleep.
On nights when your mind is busier at bedtime, falling asleep tends to take longer, even in good sleepers.
In 52 adults with two PSG nights each, higher pre-sleep cognitive arousal was linked to longer measured sleep latency, lower sleep efficiency and shorter sleep in both good sleepers and people with insomnia, while somatic arousal was not. In a 42-day diary study (n=50), bedtime stress and worries were the main predictors of that night's sleep quality.79
Limits Correlational; small samples. Associations do not show that lowering arousal on a given night will shorten onset by a set amount.
Stress and sleep work in both directions: stressful periods disturb sleep, and short or poor sleep makes the next day feel more stressful and anxious.
In 2,892 good sleepers followed for a year, each extra stressful event raised the odds of developing insomnia by 19%, and this was carried mostly by intrusive thoughts about the stressor. People differ in 'sleep reactivity' to stress. Experimental and population data show even modest sleep loss predicts higher next-day anxiety.912
Limits Observational for the stress-to-insomnia direction; sleep-loss-to-anxiety evidence comes partly from total sleep deprivation in young adults.
Trying hard to fall asleep tends to keep you awake; easing off the effort is part of most good sleep programmes.
Espie's attention-intention-effort model and Harvey's cognitive model both describe sleep effort, clock-watching and monitoring for signs of sleeplessness as arousing. In a trial of 34 sleep-onset insomniacs, paradoxical intention lowered sleep effort and sleep performance anxiety.41314
Limits Mainly theoretical models supported by small experiments; effects on objectively measured sleep onset are less consistent than on self-report.
Writing a specific to-do list for the coming days just before bed helped young adults fall asleep faster in a sleep-lab study.
57 healthy 18–30-year-olds wrote for 5 minutes before lights-out. The to-do-list group fell asleep in 15.8 min versus 25.1 min for a group writing about tasks already completed (d=0.63). More specific lists went with faster onset.15
Limits One night, one lab, healthy young adults, no no-writing control (the comparison may partly reflect the completed-list task slowing sleep). Not tested in insomnia or as a nightly habit; no replication found.
Writing about worries before bed may help some people fall asleep faster, but the evidence is from small pilot studies.
In 42 poor sleepers over three nights, writing that emphasised expressing and processing worries shortened self-reported sleep onset compared with no writing; writing about hobbies did not clearly differ.16
Limits Self-reported sleep, small analogue sample, short duration. No meta-analysis of bedtime expressive writing for sleep was found.
Spending a few minutes earlier in the evening writing down worries and a next step for each can reduce how 'wired' your mind feels at bedtime.
In 33 students with insomnia, a 5-night 'constructive worry' exercise (listing worries and possible solutions in the early evening) lowered pre-sleep cognitive arousal versus a worry-only control. In a 41-student pilot, e-mailed constructive worry, imagery distraction and gratitude exercises each reduced pre-sleep worry and arousal versus baseline.1718
Limits Small student samples, short follow-up, outcome mostly self-rated arousal rather than measured sleep onset; the Digdon pilot compared against baseline, not a no-treatment group.
Setting aside a fixed daytime slot for worrying, and postponing worries to it, may reduce worry and insomnia symptoms in people who worry a lot.
53 high-worry adults randomised to two weeks of a daily 30-minute time- and place-restricted worry period improved more on worry, anxiety and insomnia measures than a focused-worry control.19
Limits Single small preliminary trial in high worriers; insomnia was a secondary outcome.
Filling your mind with an engaging, calm imagined scene in bed can crowd out worries better than simply trying not to think.
In 41 people with insomnia, training in an interesting imagery task for the pre-sleep period shortened sleep onset and reduced unwanted thoughts compared with no instructions; general 'distract yourself' instructions did not help.720
Limits Single-night, small study; a 2020 systematic review found that attempts to change pre-sleep thinking have beneficial, negligible or even harmful effects depending on the method (thought suppression can backfire).
'Cognitive shuffling' (picturing a series of random, unrelated things) is a plausible way to quiet a busy mind, but it has not yet been properly tested.
Luc Beaudoin's serial diverse imagining technique is described in a 2019 conference abstract as a proposed treatment to be tested. A 2016 conference poster in 154 students reportedly found benefits, but no peer-reviewed trial was found.72021
Limits The developer has a commercial interest (CogSci Apps, CogZest). The closest tested relative is imagery distraction (Harvey & Payne 2002). Fine to offer as low-risk to try, not as an evidence-based treatment.
Letting yourself lie quietly awake, rather than trying to fall asleep, can ease the pressure that keeps some people up.
A 2022 meta-analysis of about 10 trials found paradoxical intention produced large improvements in insomnia symptoms versus passive controls and moderate ones versus active treatments, along with a drop in sleep-related performance anxiety.1422
Limits The authors call for methodologically stronger studies; many trials are old and small. Effects on objective sleep onset are weaker than on self-report. It is not among the 2021 AASM guideline's recommended single therapies.
If you can't fall asleep after what feels like 15–20 minutes, getting up to do something calm in dim light and returning when sleepy is one of the better-supported habits.
Stimulus control (bed only for sleep and sex, leave the bed when unable to sleep, fixed wake time) gets a conditional recommendation as a stand-alone therapy from the AASM. A component network meta-analysis of 241 trials found stimulus control was among the active ingredients of CBT-I (iOR 1.43) and linked to better sleep latency.2324
Limits Evidence comes from people with chronic insomnia; the '15–20 minutes' is a clinical rule of thumb meant to be estimated, not timed (clock-watching is itself arousing).
For long-running sleep trouble, cognitive behavioural therapy for insomnia (CBT-I) is the recommended first treatment; single wind-down habits are a lighter-touch start, not a substitute.
US (AASM 2021, ACP 2016) and European (2023) guidelines recommend multicomponent CBT-I as first-line for chronic insomnia. In component analysis, cognitive restructuring, stimulus control and sleep restriction were the components most linked to remission.2326
Limits Chronic insomnia means difficulty at least three nights a week for three months with daytime impact; the app should point such users to CBT-I rather than imply its protocol is a treatment.
General sleep-hygiene tips on their own rarely fix persistent sleep problems.
The AASM suggests clinicians not use sleep hygiene as a stand-alone therapy for chronic insomnia, and the component network meta-analysis found sleep hygiene education added little (iOR 1.01).232427
Limits This concerns chronic insomnia; individual hygiene items may still help people whose problem is specifically that habit.
Progressive muscle relaxation can help some people feel calmer and sleep better, though results vary a lot between studies.
A 2026 meta-analysis of 31 RCTs (n=2,277) found a large but very heterogeneous improvement in sleep quality (SMD −1.74, I²=92%). In a lab study of 32 young adults, 30 minutes of PMR before bed lowered heart rate and shortened sleep onset versus a neutral night. Relaxation gets a conditional AASM recommendation, but within CBT-I packages it did not add benefit (iOR 0.81, 95% CI 0.64–1.02).23242829
Limits Many included trials are in hospital or clinical groups, unblinded and small; the very high heterogeneity makes the pooled size unreliable. Stand-alone relaxation is weaker than CBT-I.
Slow breathing (around six breaths a minute) before bed is a low-risk way to settle down, but evidence that it improves sleep is still thin.
A 2026 systematic review found 9 studies (457 participants) of ≤10 breaths/min before bedtime; it judged the evidence low quality and called for better trials. In one small study, 14 people with insomnia who did 20 minutes of 0.1 Hz paced breathing before bed had shorter PSG sleep onset and fewer awakenings.3031
Limits Small, mostly uncontrolled or short studies; physiological effects on heart-rate variability are clearer than effects on sleep.
The popular 4-7-8 breathing pattern has not been tested as a sleep aid in the general population or in insomnia.
The only randomised sleep-related trial found was in 48 tinnitus patients, where six weeks of 4-7-8 breathing improved insomnia-severity scores alongside tinnitus distress. Claims that it brings sleep 'in 60 seconds' have no trial support.3032
Limits Any slow-exhale breathing may calm some people; there is no evidence that the 4-7-8 counts are special.
Regular mindfulness meditation modestly improves sleep quality, though it has not been shown to beat established sleep treatments.
A meta-analysis of 18 RCTs (n=1,654) found moderate-strength evidence that mindfulness improved sleep quality versus non-specific active controls (effect size 0.33 post-treatment, 0.54 at follow-up), but no difference versus evidence-based sleep treatments such as CBT-I. In an RCT of 54 adults with chronic insomnia, mindfulness programmes cut total wake time and pre-sleep arousal more than self-monitoring.3334
Limits Programmes were usually 6–8-week courses, not a single bedtime session; benefit from a short app meditation at bedtime is untested.
Gentle yoga or stretching done regularly may improve sleep a little; whether stretching right before bed helps on a given night has not been tested.
A meta-analysis of 19 trials in women (n=1,832) found a small improvement in sleep (SMD −0.33). In a 4-month RCT of 28 people with chronic insomnia, a stretching programme improved insomnia severity and actigraphic sleep latency (−5 min) about as much as resistance training.3536
Limits The stretching trial was a supervised daytime programme with 10 people per arm; no bedtime-stretching trial was found.
A warm bath or shower about 1–2 hours before bed can help you fall asleep a little faster; right before bed is less helpful.
A meta-analysis of 17 studies (13 pooled) found water at 40–42.5 °C for as little as 10 minutes, scheduled 1–2 h before bedtime, shortened sleep onset, by about 10 minutes on average according to the authors. In 1,094 older adults, baths 61–180 min before bed were linked to shorter measured onset.3738
Limits Small, heterogeneous studies; optimal timing and duration are uncertain. Hot baths may be unsuitable for people with heart disease, low blood pressure or who are pregnant.
Reading a paper book is a better wind-down than reading on a bright screen, which can delay your body clock and sleep.
In 12 young adults reading for about 4 h each evening for 5 nights, a light-emitting e-reader versus a printed book lengthened sleep onset by about 10 min (25.7 vs 15.8 min), suppressed melatonin by ~55% and delayed the clock by ~1.5 h. In 68 young males, 90 min of smartphone reading attenuated melatonin and reduced early deep sleep in adults compared with a printed book.3940
Limits Long, bright exposures in small lab samples; shorter or dimmer real-world use has smaller effects. No trial shows reading a book speeds sleep compared with doing nothing.
Using a phone in bed is linked to more insomnia symptoms and less sleep, mainly by pushing sleep later.
In 45,202 Norwegian students, each extra hour of screen use after getting into bed was associated with 59% higher odds of insomnia symptoms and 24 min less sleep, regardless of activity type. In 844 Flemish adults, texting or calls after lights-out predicted longer sleep latency and worse sleep. Interactive devices before bed were more linked to trouble falling asleep than passive ones like TV.4143
Limits Cross-sectional: poor sleepers may reach for their phones because they cannot sleep. One author of the Norwegian study reports employment with sleep-tech companies.
There is no tested 'right' length for a wind-down routine; 30–60 minutes of calm, dim, low-effort activity is a common clinical suggestion.
No trials compare wind-down durations. The evidence that does exist is item-specific: a 5-minute writing task right before lights-out, PMR and slow breathing for 20–30 minutes before bed, and a warm bath 1–2 hours before.15273137
Limits The 30–60 minute figure is clinical convention rather than a measured effect; consistency matters more than length.
What experts and guidelines say
- AASM 2021 (Edinger, Carney, Lichstein and others). The guideline makes six recommendations23:
- Multicomponent CBT-I: strong.
- Brief behavioural therapies: conditional.
- Stimulus control: conditional.
- Sleep restriction: conditional.
- Relaxation therapy: conditional.
- Sleep hygiene as a single therapy: conditional recommendation against.
- Paradoxical intention and mindfulness are not among the recommended single therapies.
- European Insomnia Guideline 2023 (Riemann, Espie, Spiegelhalder and others). CBT-I, in person or digital, is first-line for adults of any age. Light therapy and exercise may be useful adjuncts26.
- ACP 2016. CBT-I is the initial treatment for chronic insomnia in adults25.
- Allison Harvey (UC Berkeley). Her cognitive model holds that worry, selective attention to sleep-related threat and safety behaviours maintain insomnia4. Her trials tested imagery distraction and expressive writing2016.
- Colin Espie (Oxford). Attention-intention-effort model: good sleep is automatic, and effortful attempts to sleep inhibit it. Hence paradoxical intention1314.
- Dieter Riemann (Freiburg) and Michael Perlis (Penn). Hyperarousal and neurocognitive models132. Perlis is senior author on the component network meta-analysis24.
- Charles Morin (Laval). Major CBT-I trialist; co-authored the field's disease primer44.
- Christopher Drake and David Kalmbach (Henry Ford Health). Sleep reactivity and nocturnal cognitive arousal as treatment targets11810.
- Michael Scullin (Baylor). Bedtime to-do-list writing15.
- Luc Beaudoin (Simon Fraser University). Cognitive shuffling; has a commercial interest21.
Myths and overstatements
- Unproven
“4-7-8 breathing will put you to sleep in 60 seconds.”
No trial has tested 4-7-8 breathing for sleep onset in the general population or insomnia. Slow breathing in general has only low-quality evidence for sleep, and no technique reliably produces sleep within a minute.3032
- Overstated
“Cognitive shuffling is a scientifically proven sleep hack.”
It is a plausible idea from a researcher with a commercial stake, supported so far only by conference abstracts. The nearest tested relative, imagery distraction, helped in one small trial.72021
- Partly true
“A hot shower right before bed knocks you out.”
Warm water bathing does help onset, but the evidence points to 1–2 hours before bed so that the body has time to shed heat; immediately before bed was not shown to work as well.3738
- False
“If you can't sleep, stay in bed and keep trying — at least you're resting.”
Trying harder raises arousal, and lying awake in bed conditions the bed as a place of wakefulness. Stimulus control (getting up when unable to sleep) and reducing sleep effort are evidence-based.132324
- Overstated
“Blue light is the main reason phones in bed keep you awake.”
Large blue-light effects came from hours of bright reading in the lab. Real-world harm from phones in bed seems to come largely from delayed lights-out and lost sleep time; 30 minutes of social media in the lab barely changed arousal.293941
- False
“Writing worries down before bed just makes you dwell on them.”
Structured writing (a specific to-do list, worries with next steps) reduced pre-sleep arousal or sleep onset in small trials. What you write matters: listing completed tasks did not help.1517
- Overstated
“Good sleep hygiene and relaxation are enough to fix insomnia.”
Sleep hygiene alone is not recommended for chronic insomnia, and relaxation added little inside CBT-I packages. CBT-I (cognitive work, stimulus control, sleep restriction) is first-line.232426
- Unproven
“Meditation apps work as well as therapy for insomnia.”
Mindfulness programmes beat attention-matched controls modestly, but have not been shown to beat evidence-based sleep treatments, and most trials used 6–8-week courses, not bedtime app sessions.3334
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