Sleep Better.
Science-backed strategies to enhance recovery, performance, and longevity through optimised sleep architecture.
Explore the ProtocolSleep By The Numbers
Tap any metric to reveal the clinical context and optimisation target behind the number.
NSF guidelines: 7–9 h for adults 26–64. Below 6 h raises dementia, metabolic, and cardiovascular risk. Above 9 h may signal underlying health issues.
Each 90-minute cycle moves NREM 1→2→3→REM. 5 complete cycles = 7.5 h. Waking mid-cycle causes grogginess (sleep inertia).
Core body temp must drop ~1°C to initiate sleep. Cool rooms accelerate this. 18.3°C (65°F) is widely cited as ideal.
Slow-wave sleep drives HGH release, cellular repair, and memory consolidation. Declines with age — prioritise by consistent schedule + cool environment.
Tap any tile to reveal clinical context
The Science of Restoration
Sleep is not passive rest — it is an active, multi-stage recovery process. Optimising sleep allows your body to repair tissue, detoxify the brain via the glymphatic system, and consolidate learning, leading to measurable improvements in performance and longevity.
- Cognition: Memory consolidation, decision-making, and learning integration occur during NREM and REM stages.
- Immunity: Cytokine production peaks during sleep; chronic deprivation triples cold susceptibility.
- Metabolism: Ghrelin rises and leptin falls with sleep loss, driving hunger and insulin resistance.
- NREM Stage 3: Critical for tissue repair, human growth hormone release, and slow-wave memory consolidation.
- REM Sleep: Emotional processing, synaptic pruning, and creative insight generation.
- Glymphatic Flush: Brain cells shrink 60% during deep sleep to clear metabolic waste including amyloid-beta.
Circadian Rhythm
Your master clock — the SCN — drives every cell. Light is its primary signal.
- Light Exposure: Morning sunlight (10–30 min within 30 min of waking) anchors cortisol and suppresses late melatonin.
- Melatonin: Rises ~2 h before habitual sleep time; blocked by blue-spectrum light at night.
- Consistency: A fixed wake time is the single strongest circadian anchor — even after a late night.
- Disruptions: Shift work, jet lag, and screen exposure all fragment rhythm and reduce deep sleep.
- Temperature: Core temp naturally drops at night; warm showers accelerate this by peripheral vasodilation.
Sleep Health Cheat Sheet
Essential sleep optimisation tactics at a glance. Implement these science-backed strategies for immediate improvements.
Same sleep and wake times daily, even on weekends. Fixed wake time is the most powerful circadian anchor.
Keep bedroom between 16–20°C (60–68°F). A cooling mattress pad or open window can make a significant difference.
Blackout curtains or a sleep mask. Even dim light through eyelids suppresses melatonin production.
No screens 90 minutes before bedtime. If unavoidable, use amber-lens glasses (covered in detail below).
None 6–8 hours before sleep. Caffeine’s half-life is 5–6 hours; it still reduces deep sleep even if you fall asleep fine.
Finish intense workouts 3+ hours before bed. Morning or afternoon exercise boosts adenosine pressure and deep sleep.
90-minute pre-sleep relaxation protocol: dim lights, calm activity, coherent breathing (see section below).
Even one drink fragments REM sleep. Alcohol may help you fall asleep faster but drastically reduces restorative sleep quality.
How Light Hijacks Sleep
Intrinsically photosensitive retinal ganglion cells (ipRGCs) contain melanopsin, a pigment with peak sensitivity at ~480 nm. When activated by blue light, they signal the suprachiasmatic nucleus to halt melatonin release from the pineal gland.
Visible Spectrum — Blue Zone (380–500 nm) is highest risk
A 2020 Current Biology study found that wearing amber-tinted lenses for 2 hours before bed increased melatonin onset by 23 minutes and improved next-day alertness scores compared to a clear-lens control group.
- Screen Blue Light: Modern OLED and LCD displays emit peak energy at 450–470 nm — directly in the melanopsin sweet spot.
- LED Overhead Lights: Cool-white LEDs (4000K+) produce significant blue output. Swap for warm (2700K) bulbs after sunset.
- Candlelight / Fire: Spectral energy peaks in the red-amber range (600–700 nm) — essentially no melatonin suppression.
When & What to Wear
Begin dimming overhead lights. Clear anti-glare or very light yellow lenses reduce eye strain without fully blocking light.
Switch to amber lenses. These block 60–90% of blue light while preserving reasonable colour perception and vision clarity.
Red lenses block virtually all sub-600 nm light. Ideal for those with severe circadian disruption, shift workers, or heavy screen users. Vision is noticeably tinted — best for home use only.
Switch overhead lights to warm bulbs (2700K or lower). Use salt lamps, candles, or red light panels in the hour before sleep.
Lens Tint Comparison Guide
Choose the right tint based on screen time, timing, and sensitivity level.
| Lens Type | Blue Blocked | Colour Distortion | Best Use | Timing |
|---|---|---|---|---|
| Clear / Anti-Reflective | ~5% | Minimal | Daytime screen work; eye strain reduction | All day |
| Light Yellow | 15–30% | Subtle warmth | Afternoon screen use; mild evening exposure | Afternoon onwards |
| Amber / Orange (FL-41) | 60–90% | Moderate — warm world | Primary evening glasses; readable text; TV viewing | 2 h before bed |
| Red (DeepSleep / AltRed) | >98% | Strong — red world | Pre-sleep protocol; shift workers; severe insomnia | 90 min before bed |
Pair amber glasses with f.lux or Night Shift on screens for layered protection. The glasses handle ambient LED light that software cannot touch. On the phone: enable Greyscale Mode in accessibility settings — desaturation reduces stimulation even before melatonin suppression is considered.
Healthy vs. Unhealthy Sleep Habits
Understanding the contrast between sleep-promoting and sleep-disrupting behaviours is essential for consistent optimisation.
Healthy Habits
Evening Light Management
- Dim Lighting: Reduce light intensity 2–3 hours before bed.
- Amber Glasses: Wear amber lenses if screens are unavoidable.
- Red / Warm Light: Use 2700K or lower bulbs in evening spaces.
Evening Activities
- Reading: Physical books or e-readers with warm filters.
- Meditation: 10–20 minutes of mindfulness or body-scan practice.
- Journaling: Brain-dump and gratitude practice reduces cortisol.
- Coherent Breathing: 5–6 bpm resonance breathing for HRV upregulation (see below).
Sleep Environment
- Temperature: 16–20°C room; cooling mattress pad optional.
- Darkness: Complete blackout; tape over device LEDs.
- Sound: Pink noise or silence (< 30 dB).
- Bedding: Breathable, natural-fibre materials.
Unhealthy Habits
Evening Light Exposure
- Bright Screens: Phone, tablet, TV within 2 hours of sleep.
- LED Overhead Lights: Cool-white 5000–6500K light at night.
- No Glasses: Unfiltered screens suppress melatonin for hours.
Evening Activities
- Social Media: Stimulating, anxiety-inducing content scrolling.
- Work Emails: Stress response activates cortisol and alertness.
- News Consumption: Emotionally charged content raises arousal.
- Intense Exercise: Raises core temperature and sympathetic tone.
Sleep Environment
- Temperature: Too warm (>22°C) or too cold (<15°C).
- Light Pollution: Streetlights, phone displays, LED alarm clocks.
- Noise: TV left on, irregular traffic, inconsistent sounds.
- Clutter: Psychologically stimulating, stress-associated environment.
Coherent / Resonance Breathing
Slowing your breathing to the baroreflex resonance frequency — 5–7 breaths per minute — maximises heart-rate variability, activates the parasympathetic nervous system, and primes your body for deep, restorative sleep.
Live Breathing Guide
Recommended: 5–20 minutes nightly during your wind-down routine.
Breathe nasally. Keep shoulders relaxed.
At 5–7 breaths per minute, your breathing oscillations synchronise with your baroreflex loop, amplifying HRV amplitude to its physiological maximum. This window is sometimes called cardiac coherence.
Why the Exhale Must Be Longer
Inspiration activates the sympathetic branch (heart rate rises). Expiration activates the parasympathetic branch (heart rate falls). By making the exhale longer than the inhale, you spend more time in parasympathetic activation, progressively downregulating arousal and cortisol.
Ratio shown: 4:6 (the 6 bpm standard protocol). For advanced practice, try 4:7:8 or a 1:2 inhale:exhale ratio at any comfortable pace.
Resonance breathing synchronises baroreflex oscillations, producing the largest possible HRV amplitude — a marker of vagal tone and cardiovascular adaptability.
As few as 5 minutes of coherent breathing can measurably lower salivary cortisol and self-reported stress — making it an ideal wind-down tool before the sleep window.
Downregulating the sympathetic nervous system via slow breathing reduces sleep-onset latency — the time from lights-out to first sleep — by activating parasympathetic dominance.
RSA is the natural variation in heart rate linked to breathing. Coherent breathing maximises RSA, which is predictive of better deep-sleep duration and next-morning HRV scores on wearables.
Resonance Breathing Protocols by Goal
All protocols use nasal breathing unless stated. Breathe diaphragmatically — belly rises first.
4s in · 6s out · 5 minutes. Use with amber glasses. No breath-hold. Nasal only.
Physiological sigh: double inhale (2s + 1s) then long exhale (8s). Repeat ×5. Rapidly lowers arousal.
5s in · 5s out · 20 minutes daily. Used in clinical HRV biofeedback protocols. Maximises SDNN.
Box breathing: 4s in · 4s hold · 4s out · 4s hold · ×8 rounds. Balances HRV before cortisol peak.
10 Proven Optimisation Strategies
Fixed bed and wake times daily. The single most impactful intervention with no cost.
Dark (0 lux), cool (16–20°C), and quiet. Controls three of the four main sleep-quality variables.
Amber glasses + warm bulbs after sunset. 90 minutes minimum before lights-out.
5–6 bpm resonance breathing for 10 minutes before sleep. Activates parasympathetic tone and reduces sleep-onset latency.
No caffeine 6–8 hours before bed. It reduces slow-wave sleep even when you feel unaffected.
Daily movement improves deep sleep. Avoid intense training within 3 hours of bedtime.
Light dinner; avoid alcohol. Large meals raise core temperature and delay sleep onset.
Warm shower or bath 1–2 hours before bed triggers peripheral vasodilation, dropping core temperature.
Monitor HRV and sleep staging trends via wearable. Pattern recognition beats single-night guessing.
Magnesium glycinate (400 mg) + glycine (3 g) before bed. Evidence-backed for NREM enhancement and overnight recovery.
Routine Templates
Copy and adapt these evidence-based evening and morning routines.
- Dim all overhead lights; switch on warm lamps
- Put on amber-lens glasses
- Gentle yoga or stretching (15 min)
- Journaling / reflection (5–10 min)
- Herbal tea (chamomile, lemon balm)
- Coherent breathing session (10 min, 6 bpm)
- No screens for final 30 min
- No alarm snooze — fixed wake time
- Sunlight exposure within 30 min of waking
- Electrolyte hydration before caffeine
- Light mobility / cold shower contrast
- Protein-rich breakfast (30+ g)
- HRV reading — note trend vs. baseline
Optimisation Tools
- Oura Ring / WHOOP 4.0
- Sleep Cycle / Pillow
- BetterHealthTracker — HRV trend logging
- f.lux / Night Shift for screen warmth
- Magnesium Glycinate — 400 mg nightly
- L-Theanine — 200 mg if stress-driven insomnia
- Glycine — 3 g reduces core temp at night
- Ashwagandha (KSM-66) — cortisol adaptation
- Amber / red blue-light blocking glasses
- Blackout curtains or sleep mask
- Smart bulbs (2700K warm for evenings)
- Red-spectrum night lights
- Nasal strips (Breathe Right)
- Mouth tape (3M surgical, lightly applied)
- HRV biofeedback app (Elite HRV, HeartMath)
- This page — live 6 bpm pacer above