Sleep signal guide
Sleep stages
Direct answer
Direct answer
Sleep moves through non-REM and REM stages across repeated cycles. Consumer wearables estimate these stages from indirect signals, so trends can be useful while minute-by-minute labels remain approximate.
How to use it
- ✓Notice broad multi-night patterns
- ✓Understand why awakenings are more memorable later
- ✓Add context to a coaching conversation
What it cannot prove
- !Not a sleep-lab measurement
- !Algorithms differ by brand
- !A stage score should not overrule how you feel
Sources and further reading
- 1