Sleep Plan
Plan the total and the consistency. The cycle arithmetic picks a bedtime; it does not pick a wake-up minute.
BFCBrilliance · bfcbrilliance.com/tools/sleep-cycle-calculator
My plan
- Date
- Target wake time
- Cycles
- Cycle length
- Time to fall asleep
- TIME IN BED
- ACTUALLY ASLEEP
- vs 7 hours
- Lights out at
- Alarm at
- Wind-down starts at
What is established, and what is not
- Adults 18-60 should sleep
- 7+ hours (AASM/SRS consensus)
- Typical night
- 4-5 cycles
- Average cycle
- about 90 min
- ⚠ Documented range
- 70-120 min
- ⚠ First cycle
- SHORTEST — 70-100 min
- Later cycles
- longer — 90-120 min
- Stage order
- N1 → N2 → N3 → N2 → REM
- Deep slow-wave sleep
- heaviest in cycles 1-2
- REM
- heaviest in the last cycles
- ⚠ So a short night
- costs mostly REM, not a fair slice
- Normal time to fall asleep
- about 15 min
- Waking from deep sleep
- sleep inertia — the groggy feeling
- ⚠ '5 cycles' spans
- 5h50m to 10h — a 250 min spread
Two-week sleep diary
| Date | Lights out | Woke | Times awake | How I felt 1-5 |
|---|---|---|---|---|
The things that actually move sleep
- Same wake time every day, including weekends
- Total planned sleep is 7 hours or more
- Wind-down started 30-60 min before lights out
- No caffeine after early afternoon
- Bedroom dark, quiet and on the cool side
- Screens out of the last stretch before bed
- Alcohol understood as a REM suppressant, not a sleep aid
- Bed used for sleep, so the association stays clean
- If awake more than 20 min, get up rather than lie there
- Sleep diary kept for two weeks before changing anything
- Persistent trouble taken to a doctor, not to a calculator
'Five cycles' is not a time
At 70 minutes it is 5h50m of sleep; at 120 it is 10 hours. That 250-minute spread is what a wake-up time quoted to the minute is hiding. Use the arithmetic to pick a bedtime, not to pick a minute.
The cycles are not equal
The first is the shortest (70-100 min) and later ones run longer (90-120). Multiplying one constant by five is wrong in a structured direction, and the error accumulates across the night rather than averaging out.
A short night costs REM specifically
Deep restorative sleep is concentrated early; REM is concentrated late. An hour cut off the end removes most of your REM and leaves deep sleep intact. Losing an hour is not one thing — when you lose it matters.