Temperature is one of the most underutilized sleep optimization tools. Sleep onset requires a drop in core temperature, while skin temperature increases. This protocol uses room temperature, bed temperature, hot showers, and timing to create the optimal thermal environment for sleep.
Step-by-Step Protocol
Room Temperature
Throughout nightSet bedroom temperature to 65-68°F (18-20°C). Cooler is generally better. This should feel slightly cool when getting into bed.
Bed Temperature
Throughout nightIf using Eight Sleep, ChiliPad, or similar, set to cool mode (60-65°F bed surface). Program warming 30 min before wake time for natural wake-up.
Pre-Sleep Hot Shower
60-90 min before bedTake a hot shower or bath 60-90 minutes before bed. This dilates peripheral blood vessels, then the subsequent heat loss drops core temperature.
Light Bedding
During sleepUse breathable, light bedding. Avoid heavy comforters that trap heat. Natural fibers (cotton, linen, wool) breathe better than synthetics.
Sleepwear
During sleepWear light, breathable sleepwear or sleep nude. Heavy pajamas trap heat and impair temperature regulation.
Avoid Late Exercise
3-4 hours before bedFinish intense exercise 3-4+ hours before bed. Exercise raises core temperature, which must then normalize before sleep.
Avoid Late Eating
3+ hours before bedFinish eating 3+ hours before bed. Digestion raises core temperature through thermogenesis.
Warm Feet
At bedtimeIf feet are cold, wear socks to bed. Warm extremities facilitate core temperature drop through vasodilation.
The Science Behind It
Sleep is intricately linked to thermoregulation. The circadian system lowers core temperature 1-2 hours before typical bedtime, signaling melatonin release and sleep onset. Core temperature reaches its minimum about 2 hours before natural wake time. Disrupting this pattern (hot rooms, late eating, evening exercise) delays sleep onset and reduces deep sleep. The hands, feet, and face are 'radiators' that dump heat - warming them paradoxically cools the core.
Expected Results
Common Mistakes to Avoid
- Bedroom too warm (most common mistake)
- Heavy blankets that trap heat
- Hot shower right before bed (too late)
- Late-night eating
- Evening intense exercise
- Synthetic sheets that don't breathe
What You'll Need
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