Wake, sleep, or nap — timed to full cycles
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Your 24-hour window
Bedtime options
What happens during a sleep cycle?
Entry point of every cycle. Heart rate slows, muscles relax — easy to wake without grogginess.
Body repairs tissue and strengthens immunity. Heaviest in early cycles — waking here causes grogginess.
Dreams and emotional processing. REM windows grow longer each cycle — why mornings feel dream-heavy.
Most adults feel best after 4–6 full cycles (6–9 hrs). Waking between cycles rather than mid-cycle feels less groggy — that's the gap Lull lines up for you.