Restorative Sleep adds up the deep and REM sleep you got each night and shows it as a simple bar chart with your average and your best night. It then looks across your own nights to show what tends to go with your most restorative sleep.
The card draws one bar per night for the deep and REM sleep you got, with an average line across the window and a Best Night callout. It is a quick way to see whether recent nights have been giving you the kind of sleep that leaves you feeling recovered, not just the number of hours.
Beneath the chart, FitRest lists findings drawn from your own nights. Depending on what your data shows, these include your best nights, whether longer nights brought you more restorative sleep, and whether steadier bedtimes did. They are patterns in your history, written in plain language, not general rules.
Open the details for a fuller picture of the window you have selected.
Not all sleep does the same job. Deep sleep is the stage most associated with physical recovery: it is when the body releases growth hormone and does much of its repair. REM sleep is linked with memory, learning and emotional processing. Light sleep makes up most of the night and matters too, but deep and REM are the stages people most often mean when they talk about waking up refreshed.
Because deep sleep is concentrated in the first part of the night and REM in the last part, both a late bedtime and an early alarm can cut into them in different ways. Tracking the two together helps you see the cost of a short night more clearly than total hours alone, and shows you which habits, like a steadier bedtime, are linked with better nights for you.
FitRest does not hold you to a population target for restorative sleep. Devices measure sleep stages differently, so your own trend matters more than any single number. Use the chart to compare yourself with yourself: a week that sits above your usual average is a good sign, and a run of low nights is worth a look at your schedule.
Nights without sleep stage data are left out rather than counted as zero, so a night recorded only as time in bed will not drag your average down. Restorative Sleep is a wellness summary, not a medical diagnosis.
In FitRest, restorative sleep is your deep sleep plus your REM sleep for the night, the two stages most linked with physical recovery and memory.
It varies from person to person, and devices measure stages differently. FitRest compares each night with your own average instead of a fixed target.
Nights without sleep stage data, such as nights recorded only as time in bed, are left out so they do not pull your average down.
Yes. It uses the sleep stages your Apple Watch, or another device that saves sleep stages to Apple Health, records while you sleep.
Time in bed, actual sleep, sleep stages and overnight heart rate for every night and nap.
A one-square-per-night heatmap of your sleep across 13 metrics.
Your chronotype, schedule consistency and sleep trends from your own nights.
A 0-100 score for each night's sleep, with a label, a comparison with your recent average and the factor that held it back.
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FitRest reads the data already in Apple Health, so there is nothing to set up beyond granting access.
iPhone, iPad and Apple Watch. Requires iOS 17 or later.