Sleep Hygiene

"Sleep hygiene" is the set of controllable habits that make falling and staying asleep easier and protect sleep architecture. The highest-yield practices:

• Consistent schedule — same bed/wake time, including weekends; anchors the circadian clock (circadian-rhythm). The wake time is the most powerful anchor.
• Dark, cool, quiet room — darkness supports melatonin; a cool room (~18 °C / ~65 °F is a common guide) aids the natural core-temperature drop that initiates sleep.
• Limit caffeine late — caffeine has a long half-life (~5–6 h); avoid it in the afternoon/ evening (see caffeine-and-sleep).
• Limit alcohol near bed — alcohol speeds sleep onset but fragments sleep and suppresses REM, worsening quality (see alcohol-and-fitness).
• Dim lights and cut screens before bed — bright/blue light suppresses melatonin and delays sleep onset (see screen-time).
• Wind-down routine — 30–60 min of low-arousal activity (reading, stretching, breathing) signals the body to downshift; pairs with stress management (stress-management).
• Reserve the bed for sleep — strengthens the bed→sleep association; if awake >20 min, get up and do something calm, then return.
• Get morning daylight and daytime movement — both strengthen circadian timing.
• Don't train too late/too intense right before bed for some people, though regular exercise overall improves sleep.

Sleep hygiene is itself a set of habits — building it benefits from cue-routine-reward design (see habit-formation).

• Keep a consistent schedule; fix the wake time first.
• Bedroom: dark, cool (~18 °C/65 °F), quiet.
• Avoid afternoon/evening caffeine (half-life ~5–6 h) and pre-bed alcohol.
• Dim lights / cut screens 30–60 min before bed; build a wind-down routine.

• circadian-rhythm — what consistent timing entrains.
• caffeine-and-sleep / alcohol-and-fitness — substances that disrupt sleep.
• screen-time — light and arousal before bed.
• habit-formation — building the routine.