Sleep Architecture: What Happens Across a Night
A night of sleep runs four to six NREM-REM cycles with deep sleep front-loaded and REM back-loaded, and consumer trackers misjudge both.
Niche
Sleep
Sleep architecture, circadian timing, and what actually improves sleep quality.
Morning Light: The Highest-Evidence Circadian Habit
Light after waking advances the body clock through melanopsin-carrying retinal cells, and outdoor illuminance beats indoor lighting by a factor of eight or more.