Sleep Health Metrics shows the readings your body records overnight, respiratory rate, sleep disruptions, sleeping HRV and wrist temperature, and compares each with your own usual range. Blood oxygen and overnight heart rate sit alongside them in each night's detail.
The card has four rows, each comparing last night with your own usual range: Respiratory Rate in breaths per minute, Sleep Disruptions as awakenings, Sleep HRV in milliseconds, and Wrist Temperature as a deviation from your normal. Each row has a status such as Typical, Elevated or Below Baseline, or Building your baseline while FitRest is still learning what is normal for you.
A closing line sums up the night. On most nights it will tell you every marker sat in your usual range. When one does not, it reminds you that one night on its own is rarely meaningful and that a run of two or three is more worth noticing.
Each metric opens into its own screen with the night, your typical range and trends over time.
Sleep is the most stable part of your day. You are lying still, you have not eaten or exercised for hours and nothing is pulling at your attention, which makes it a good time to see your body's baseline. That is why readings like breathing rate, heart rate variability and skin temperature are often more useful overnight than during the day.
These measures vary a lot between people, so what matters is how a night compares with your own normal. A sleeping HRV that sits higher than usual often goes with being well rested, while a run of nights with a faster breathing rate, a warmer wrist or more time awake can reflect hard training, alcohol, a late meal, stress or simply a change in your routine. Waking briefly is normal, and the total time awake and whether any single break ran long tell you more than the number of wake-ups.
FitRest is not a medical device and these readings are for general wellness. If you are worried about your breathing, oxygen levels, temperature or sleep, talk to a doctor.
Overnight vitals come from Apple Health. They need an Apple Watch, or another device that records these readings and saves them to Apple Health, worn to bed. Wrist temperature needs Apple Watch Series 8, Apple Watch Ultra or later. Each metric shows Building your baseline for its first nights while FitRest learns what is usual for you.
It varies between people, which is why FitRest compares each night with your own typical range rather than a fixed number.
Wrist temperature needs Apple Watch Series 8, Apple Watch Ultra or later, worn while you sleep.
Readings taken while you are awake in bed can look quite different. Leaving them out keeps the night's numbers about your sleep.
Brief wake-ups are normal. The total time spent awake and whether any single break ran long matter more than the number of times you woke.
No. FitRest is a wellness app, not a medical device. If any reading worries you, talk to a doctor.
Time in bed, actual sleep, sleep stages and overnight heart rate for every night and nap.
Resting heart rate, HRV, walking heart rate, blood oxygen and daily range in one place, with trends and readings that stand out against your own normal.
A one-square-per-night heatmap of your sleep across 13 metrics.
Three guided breathing patterns on iPhone, saved to Apple Health as Mindful Minutes.
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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.