Apple watch

How to Use Apple Watch Advanced Sleep Stage Tracking

If you’re having trouble sleeping, the Apple Watch can help you figure out what’s going on. New to watchOS 9, it can track the sleep phase you’re in. This means you can see if you’re not getting enough deep sleep or REM sleep, or if you’re waking up too often in the middle of the night. If you suffer from insomnia or sleep apnea, this information could be very useful to you.

Read on to learn how to use advanced sleep stage tracking in watchOS 9.

How to Track Sleep Stages with Apple Watch in watchOS 9

watchOS 9 offers some other great improvements for the features people use the most on the Apple Watch – health and fitness tracking. The updates don’t match the huge range of new features coming to iOS – customizable lock screens, revamped focus modes, iCloud Shared Photo Library and much more, but these improvements will give you an even better picture of your health.

These features will be available on your Apple Watch when watchOS 9 arrives this fall. To use it now, you will need to install iOS 16 and watchOS 9 public betas on your iPhone and Apple Watch. Running pre-release software comes at the cost of lower reliability and poorer battery life, so proceed with caution.

How to enable sleep tracking

Change your sleep schedule in Clock.
Screenshot: D. Griffin Jones/Cult of Mac

To enable sleep tracking, you must first set up a sleep schedule.

On your iPhone, open The clock and press To change to make sure your sleep schedule is set correctly. If you haven’t set it up yet, tap To light up. Faucet Change sleep schedule in Health to go to the next step.

Enable sleep settings in the Health app.
Enable sleep settings in the Health app.
Screenshot: D. Griffin Jones/Cult of Mac

From here you can activate Use program for sleep focus. This will automatically mute incoming phone calls and messages while you should be sleeping.

To light up Track time in bed with iPhone so it can know if you are sleeping or waking up in the middle of the night if you are using your phone. If you go a night without wearing your watch, it’s a good idea to activate it as a backup.

sleep reminders will alert you if it’s getting late and you aren’t asleep yet. I turned this feature off after a while because I have a fairly consistent schedule. If you are a student and/or often lose track of time late at night, this might be useful for you.

Sleep Results will send you a notification in the morning letting you know if you hit or miss your goal.

Turning on advanced sleep tracking for Apple Watch is easy.
Turning on sleep tracking is easy.
Screenshot: D. Griffin Jones/Cult of Mac

Faucet Manage sleep in the Apple Watch app or open it look app and press Sleep.

Faucet Use this watch to sleep to activate it. Make sure Track sleep with Apple Watch is authorized.

Enable Charging reminders to receive an alert if bedtime is approaching and your Apple Watch is low. I found that one night of sleep tracking consumes about 20% of my watch’s battery.

Sleep

The most important step in Apple Watch sleep tracking: Get a good night’s sleep.

Be sure to wear a comfortable wristband at night. My wife banned my beloved Speidel Twist-O-Flex Strap because it pinches. A Sport group (or one of the Nylon bands in the Cult of Mac Store) would do just fine. I did not wear the Milanese Loop overnight and I have no intention of doing so.

Where to find sleep stage tracking data for your Apple Watch

Find your sleep data in the Health app.
Find your Apple Watch’s sleep stage tracker in the Health app.
Screenshot: D. Griffin Jones/Cult of Mac

At dawn (or, according to my screenshots, early afternoon), you can feast on your sleep data.

Open the Health app and press Sleep > View more sleep data to see the full breakdown of your sleep phase.

See a breakdown of the time you spent in each sleep stage.
See detailed information about the time you spent in each sleep phase. In the image on the right, you can really see the amount of extra data collected once you enable sleep features on the Apple Watch.
Screenshot: D. Griffin Jones/Cult of Mac

Faucet D, W, M, 6M to see how your sleep changes over time. Then, explore the tabs for more information:

  • The Steps The tab shows how much time you spend in each stage, in minutes or percentages (if you scroll down).
  • The The amounts compares the time you spend in bed and the time you spend sleeping.
  • The Comparisons compares your sleep time to your breathing rate — important information if you suffer from sleep apnea.
You can find good summaries of your data and more information about the different stages of sleep.
You can find good summaries of your data and more information about the different stages of sleep.
Screenshot: D. Griffin Jones/Cult of Mac

Faucet Do to return to sleep – the Sleep section of the Health app, not the state of consciousness.

Scroll down to see your highlights and trends; faucet Display all To see more. The Health app will give you a summary of how long you slept last night, your heart rate, your breathing rate, and how much time you slept last week.

If you scroll even further, you’ll find articles written by Apple’s Health team to learn more:

“Understanding the Stages of Sleep” describes the four stages of sleep. You might be surprised how often you wake up during the night, even if you’re not aware of it. Apple says “it’s normal for people to wake up occasionally,” and it’s possible you forget to wake up at all.

“Why Sleep Is So Important” explains the many health benefits of a full night’s sleep. How do you know if you’re getting enough? If you wake up groggy and tired, you need more. It’s so simple.

“Getting a good night’s sleep” offers some tips that will help you sleep better:

  • Go out and get some sun.
  • Avoid napping within six hours of sleep.
  • Dim the lights as bedtime approaches.
  • Most importantly, stick to a consistent schedule.

If you are looking to read more, look at this Washington Post article which explains what metrics you should focus on. Take its hardware recommendations with a grain of salt, as the article was written before the unveiling of Apple Watch’s new sleep phase tracking feature.