The Sleep Cave
Make the bedroom dark, quiet, cool, and comfortable
- Difficulty
- Easy
- Time to result
- ~days to results
- Steps
- 4
- Confidence
- 98%
Mah organizes the sleep environment around four properties: dark, quiet, cool, and comfortable. Darkness can come from blackout curtains or an eye mask. Noise can be reduced with earplugs or masked with white noise, especially when external sounds cannot be controlled. For temperature, she cites 60 to 67°F as a range shown to help some people fall and stay asleep, but stresses that it may feel too cold for some. Her practical method is to lower the temperature by one or two degrees every few days until the individual finds a comfortable setting. Portable tools make the same framework usable in hotel rooms and on planes, while temperature-regulating mattress covers can accommodate partners with different preferences.
Origin
Extracted from The Diary of a CEO
Core principles
- 01The sleep environment should resemble a cave
- 02Light and uncontrolled noise can interfere with sleep
- 03A cooler room may support falling and staying asleep
- 04Personal comfort still determines the final setup
How to run it
- 1
Darken the room
Use blackout curtains or an eye mask to reduce unwanted light. Favor an eye mask when travelling because it works across unfamiliar rooms.
Pro tip Keep a travel eye mask with luggage rather than relying on hotel curtains.
- 2
Control the soundscape
Reduce noise with earplugs or mask unpredictable sounds with white noise. Mah says relaxing audio may be acceptable for someone accustomed to it, while she discourages sleeping with a bright television on.
Pro tip A small white-noise device can make the setup portable.
Watch out Avoid audio or screens that are psychologically stimulating for you.
- 3
Cool the room gradually
Lower the temperature by one or two degrees every few days. Stop at the setting that feels comfortable and appears to support sleep.
Pro tip Use separate temperature controls or bedding if partners prefer different conditions.
Watch out Do not force the cited 60 to 67°F range if it is uncomfortably cold for you.
- 4
Standardize the essentials
Identify which environmental tools make the largest difference and reproduce them when away from home. Keep the setup simple enough to use consistently.
In the wild
Mah recommends taking an eye mask, earplugs, and a small white-noise machine into a non-ideal hotel room. These tools reduce dependence on the room's curtains and external sound conditions.
→ A more consistent sleep environment while travelling.
Common mistakes
Using one temperature for everyone
The cited cool range is not a mandate. Mah explicitly advises finding the temperature that works for the individual.
Leaving a bright television on
Mah distinguishes relaxing audio from a television's light and stimulation in the period before sleep.
Is it for you?
Best for
It is best for people whose rooms are bright, noisy, warm, or inconsistent across locations.
Not ideal for
It is not sufficient on its own for persistent insomnia, sleep apnea, or symptoms requiring clinical evaluation.
From the transcript
“make your sleep environment like a cave really dark quiet cool and comfortable”
“you have to find the temperature that's right for you”
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