Tagged “Sleep Stages”

Sleep stages and cyclesLight, deep and REM sleep, why deep sleep comes early and REM comes late, and why "90-minute cycles" aren't precise.
- Evidence: Strong
- Low effort
- Free
- Works: tonight
How accurate are wearables?Sleep trackers are good at telling sleep from wake and at total sleep time. They are weaker at spotting time awake and at sleep stages.
- Evidence: Some
- Low effort
- Free
- Works: today