How to Read a Sleep Tracker Report: What the Numbers Mean
Learn what metrics like sleep score, REM percentage, and heart rate variability represent on a typical consumer sleep tracker, and which figures deserve attention versus which are noise.
Science-backed strategies to recover from accumulated sleep debt, interpret wearable metrics, and protect restorative rest.
Learn what metrics like sleep score, REM percentage, and heart rate variability represent on a typical consumer sleep tracker, and which figures deserve attention versus which are noise.
This explainer defines sleep debt as an accumulated shortfall of sleep hours and distinguishes it from chronic fatigue, a persistent tiredness that does not resolve with extra sleep.
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