Sleep & Recovery — Quick Reference
Sleep needs by age
|---|---|
| Adults (18-64) | 7-9 hours |
|---|
| Older adults (65+) | 7-8 hours |
| Teenagers (14-17) | 8-10 hours |
| School age (6-13) | 9-11 hours |
Sleep architecture
N1 (5-10 min) — light sleep, easy to wake
N2 (~20 min) — true sleep onset, temp/HR drop
N3 (20-40 min) — deep sleep, hardest to wake, physical restoration
REM (20-25% total) — dream sleep, memory consolidation
1 cycle ≈ 90 min. 5 cycles ≈ 7.5 hours.
Environment checklist
[ ] Temperature: 65-68°F (18-20°C)
[ ] Darkness: 0 lux — blackout curtains / sleep mask
[ ] Noise: < 30 dB or consistent white/pink noise
[ ] Phone: outside bedroom or face-down, DND on
Timing checklist
[ ] Consistent wake time — even weekends (most powerful signal)
[ ] Morning light within 30 min of waking, no sunglasses
[ ] Evening light dimmed after sunset
[ ] Caffeine cutoff: 12-14 hours before bed
[ ] Alcohol avoided, especially close to bedtime
Jet lag — light direction by travel direction
Traveling EAST (losing time) → seek MORNING light, avoid evening light
Traveling WEST (gaining time) → seek EVENING light, avoid morning light
Napping guide
10-20 min, early-mid afternoon → low risk, genuine alertness boost
60-90 min → more restorative but risk of
grogginess if cut mid-cycle
Late afternoon/evening nap → reduces nighttime sleep pressure
Common problems → likely causes
|---|---|
| Can't fall asleep | Racing thoughts, room too warm, late caffeine, blue light |
|---|
| Wakes mid-night | Alcohol, fluids before bed, stress, possible sleep apnea |
| Can't wake up | Social jet lag (late weekends), insufficient morning light |
Sleep apnea red flags — seek diagnosis, not hygiene fixes
[ ] Loud, habitual snoring (often reported by a partner)
[ ] Witnessed breathing pauses during sleep
[ ] Waking unrefreshed despite adequate time in bed
[ ] Morning headaches
[ ] Excessive daytime sleepiness despite "enough" hours
Supplement quick facts
Melatonin — best for circadian TIMING shifts (jet lag, delayed
phase), not as a nightly general sedative; effective doses
often 0.5-3mg, lower than many OTC products
Magnesium — modest evidence, most relevant with genuine deficiency
Minimum viable tracking (free)
Bedtime + wake time + subjective morning freshness (1-10 scale)
