You've been thinking about sleep all wrong. It's not about hours — it's about cycles...
Sleep is structured in 90-minute cycles moving from light NREM through deep NREM to REM. Adults need 4-6 complete cycles — that's 6 to 9 hours. Waking mid-cycle triggers sleep inertia and grogginess regardless of total hours logged.
Missing 10 hours of sleep takes up to 14 days to fully recover.
You've been thinking about sleep all wrong.
It's not about hours — it's about 90-minute cycles.
NREM light, NREM deep, REM.
Each cycle takes 90 minutes.
You need 4-6 complete cycles: 6 to 9 hours.
Wake mid-cycle and you feel destroyed no matter how long you slept.
Wake at the end of a cycle and you feel rested.
Backward from your alarm: 90-minute math.
That's your real bedtime..
Calculate your ideal bedtime backward from your wake time using 90-minute math. You will feel the difference immediately.
Put the science into practice — get your numbers instantly.
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