Sleep
Your Sleep Score and the metrics behind it: stages, efficiency, debt, consistency, and overnight heart rate.
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Common questions
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How Zolt Reads Apple Watch Sleep Stages
What Awake, Core, Deep, and REM mean in Zolt, where those estimates come from, and how to handle missing stage data.
How to Read Sleep Efficiency in Zolt
What sleep efficiency measures, where the data comes from, and how to investigate a low or surprising result.
How to Read Sleep Debt in Zolt
What your sleep balance means, how your sleep goal affects it, and what to check when the result looks wrong.
How to Read Sleep Consistency in Zolt
How Zolt helps you spot changes in sleep timing, what an irregular pattern can mean, and what the metric cannot prove.
How to Read Pre-Sleep Heart Rate in Zolt
What the pre-sleep heart-rate view shows, how to compare it with your own history, and what can affect the reading.
How to Read Heart-Rate Dip During Sleep
What the overnight heart-rate change in Zolt means, why your personal trend matters, and how to check a surprising result.
How to read your Zolt Sleep Score
What the Sleep Score summarizes, where its data comes from, and how to interpret the breakdown and trend.
Read article →Why Is My Sleep Score Low Even Though I Slept Long Enough?
Why sleep duration is only one part of the score and how to check efficiency, awake time, stages, and source data.
Read article →How Zolt Reads Apple Watch Sleep Stages
What Awake, Core, Deep, and REM mean in Zolt, where those estimates come from, and how to handle missing stage data.
Read article →How to Read Sleep Efficiency in Zolt
What sleep efficiency measures, where the data comes from, and how to investigate a low or surprising result.
Read article →How to Read Sleep Debt in Zolt
What your sleep balance means, how your sleep goal affects it, and what to check when the result looks wrong.
Read article →How to Read Sleep Consistency in Zolt
How Zolt helps you spot changes in sleep timing, what an irregular pattern can mean, and what the metric cannot prove.
Read article →How to Read Pre-Sleep Heart Rate in Zolt
What the pre-sleep heart-rate view shows, how to compare it with your own history, and what can affect the reading.
Read article →How to Read Heart-Rate Dip During Sleep
What the overnight heart-rate change in Zolt means, why your personal trend matters, and how to check a surprising result.
Read article →