What sleep stages are
Sleep occurs in repeating cycles made up of different stages.
- Light sleep
- Deep sleep
- REM sleep
See the Sleep Stages Chart.
Deep sleep
Deep sleep supports physical recovery, immune function and tissue repair.
REM sleep
REM sleep is associated with dreaming, memory consolidation and brain recovery.
What the Value Means in Practice
The meaning of Sleep Stages always depends on context. A good value is not simply “high” or “low,” but appropriate for your situation.
How to Interpret the Value
Useful questions include:
- What does the trend look like across several days?
- Does the value fit your sleep and recovery data?
- Was there stress, alcohol, illness or hard training?
- Is the value far from your personal baseline?
Useful Internal Links
Recommended SLEEP Trackers
Understand Your Health Data
LongLife Scan analyzes wearable health data and helps you understand patterns in stress, sleep and recovery.
Try LongLife ScanRelated Metrics
Health Metrics
Overview of wearable health metrics including HRV, VO2max, sleep and recovery.
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Related Charts
Body Battery Chart
Body Battery charts show how wearable devices estimate energy, recovery and stress patterns during the day.
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HRV Chart – Typical Heart Rate Variability Ranges
HRV trends show recovery and stress patterns over time.
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Recovery Score Chart
Recovery score charts show how wearables combine HRV, sleep and stress signals into one readiness value.
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Sleep Score Chart – Sleep Quality Explained
Sleep score charts show typical score ranges and help interpret wearable sleep quality estimates.
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Sleep Efficiency Chart
Sleep efficiency charts show how much of your time in bed is spent sleeping and help interpret sleep continuity.
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Sleep Stages Chart
Sleep stages charts show how sleep cycles are distributed between light sleep, deep sleep and REM sleep.
View Chart →