Apple Fitness Sleep Tracking: How Does It Work?

Apple Watch users can track their sleep using the Sleep app, which is compatible with the Series 3 or newer, SE, or Ultra models. The Sleep app allows users to set sleep goals, create sleep schedules, and view sleep history. Apple Watch's sleep tracking capabilities include recording the total time asleep, tracking the number of times the user wakes up throughout the night, and measuring heart rate and calorie burn. However, it is important to note that Apple Watch cannot diagnose sleep conditions, and users should consult a doctor if they notice any issues. Additionally, third-party apps are available for more comprehensive sleep tracking.

Apple Watch sleep tracking features

Apple Watch does track sleep, and it has several features to help you understand your sleep patterns and improve your sleep habits. Here are some key sleep tracking features of the Apple Watch:

Sleep Tracking Data:

The Apple Watch can record your total time asleep, tracking each time you wake up throughout the night. It also monitors your heart rate, respiratory rate, and calorie burn. With watchOS 9 and newer models, it can even track your wrist temperature while you sleep. This data can provide insights into your overall health and help you understand your sleep quality.

Sleep Stages:

Apple Watch can break down your sleep into different stages: REM, Core, and Deep Sleep. This allows you to see how much time you spent in each stage and how much time you were awake during the night. This feature is available with watchOS 9 and later.

Sleep Schedules:

You can create personalized sleep schedules on your Apple Watch. This includes setting a sleep goal, bedtime, and wake-up time. The Health app on your iPhone or the Sleep app on your Apple Watch can help you set and adjust your sleep schedule. You can also enable Sleep Focus to reduce distractions and notifications on your devices before bedtime.

Sleep History:

The Health app on your iPhone or iPad allows you to view your sleep history. You can see daily, weekly, monthly, and biannual sleep time averages. This data is presented in bar graphs and can be further explored by tapping "Show More Sleep Data" to review additional sleep details, such as sleep duration and sleep stages.

Third-Party Apps:

While the Apple Watch offers built-in sleep tracking features, you can also use third-party apps for more actionable insights and sleep analysis. These apps might provide a more comprehensive understanding of your sleep patterns and offer additional tools for improving your sleep quality.

It's important to note that Apple Watch sleep tracking has some limitations, and it might not be as accurate or insightful as dedicated sleep tracking devices or third-party apps. Additionally, the Apple Watch cannot diagnose sleep conditions, and you should consult a doctor if you have concerns about your sleep health.

Third-party sleep tracking apps

While the Apple Watch does offer sleep tracking capabilities, there are several third-party sleep tracking apps available that can provide additional insights and features. These apps often offer more precise data and interpretations than the built-in Apple Sleep app. Here are some popular third-party sleep tracking apps:

• Sleep Cycle: This app uses sound analysis to track your sleep patterns and provide detailed sleep statistics and graphs. It can detect sounds like snoring and coughing, and it has a gentle alarm that wakes you during your lightest sleep phase. Sleep Cycle also offers premium features such as sleep sounds and stories, relaxation guides, and the ability to compare your sleep patterns to world sleep statistics.
• Oura: The Oura app, used in conjunction with the Oura Ring, learns your sleep patterns and provides personalized tips and reminders to improve your sleep quality. It tracks your sleep cycles and provides insights into your sleep and recovery patterns. The app is free to download, but a membership is required to access all the features.
• Fitbit: Fitbit devices offer a Sleep Profile program that analyzes users' sleep on a monthly basis and assigns a sleep profile based on their habits. It provides insights and helps you understand your sleep patterns.
• Pixel Watch: The Pixel Watch series from Google also offers Sleep Profile, similar to Fitbit, and provides monthly sleep analysis and insights.
• Galaxy Watch: Samsung's Galaxy Watch series includes sleep tracking functionality, with the added benefit of sleep apnea detection, which is certified by the FDA. However, this feature requires a Galaxy smartphone to function.

These third-party sleep tracking apps offer a range of features and insights that can help you better understand your sleep habits and make improvements where necessary. They often provide more detailed data and interpretations than the basic sleep tracking offered by the Apple Watch, making them a valuable tool for those seeking to optimize their sleep quality.

Sleep tracking with watchOS 9

Sleep tracking is available on watchOS 8 or later. With watchOS 9, Apple enhanced the built-in Sleep app on the Apple Watch by introducing Sleep Stages. This feature allows the Apple Watch to tell you how much time you spent in REM, Core, or Deep sleep during the night, along with the amount of time that you were awake. You can also compare this data with the heart rate, respiratory rate, and (on Apple Watch 8 and Apple Watch Ultra models) wrist temperature measurements that your Apple Watch can take throughout the night.

To begin tracking your sleep with the Apple Watch, you need to set up a sleep schedule on your iPhone or Apple Watch. Launch the Health app on your iPhone and tap "Get Started" under Set Up Sleep, then tap Next. Set the number of hours you'd like to spend asleep, your bedtime, and wake-up times. You can also set up Sleep Focus, which reduces distractions before you go to bed and keeps you safe from interruptions while you sleep.

To receive sleep data, make sure your Apple Watch is charged to at least 30% before bed with Sleep Tracking on Apple Watch enabled, and wear your Apple Watch to sleep for at least 1 hour each night. If you don't wear your Apple Watch to sleep, your graph might not show any data. To view your sleep history, open the Health app on your iPhone or iPad and tap Browse at the bottom of the screen. Tap Sleep, and you'll see your sleep history for the past week, month, or 6 months. Tap Show More Sleep Data and select a category to review additional sleep details, including the time and percentage you spent awake or in REM, Core, or Deep sleep.

While the Apple Watch can track your sleep, it doesn't summarize the data as well as its competitors. It also cannot diagnose sleep conditions, so you'll still need to visit the doctor if you notice anything off.

Sleep tracking accuracy

The Apple Watch can track your sleep, but there are some limitations to its accuracy. With watchOS 9, Apple introduced Sleep Stages, which allows the watch to tell you how much time you spent in REM, Core, or Deep sleep, as well as the amount of time you were awake. This data can be compared with heart rate, respiratory rate, and wrist temperature measurements. However, Apple's sleep tracking data has been described as mediocre when compared to its competitors, and it does not summarize the data as well.

The Apple Watch is not able to diagnose sleep conditions, so you will need to visit a doctor if you notice anything unusual. While it can provide insights into your sleep habits, it may not be as accurate as dedicated sleep tracking devices or apps. For example, a 2017 study found that the Fitbit Charge 2 detected sleep onset with 96% accuracy but overestimated time spent asleep by 9 minutes on average. The same study found that it detected light sleep with 81% accuracy, deep sleep with 49% accuracy, and REM sleep with 74% accuracy.

In terms of comfort, the Apple Watch Series 8 has been described as uncomfortable to wear while sleeping, which may impact its accuracy. The Pixel Watch 3, on the other hand, has been praised for its lightweight and compact design, making it ideal for comfortable sleep tracking. It is also worth noting that the Apple Watch needs to be charged to at least 30% before bed and worn for at least 1 hour each night to effectively track sleep.

While the Apple Watch may not be the most accurate sleep tracker on the market, it can still provide valuable insights into your sleep habits and help you create a sleep schedule. If you already own an Apple Watch, it is worth trying out the sleep tracking features before investing in a separate device dedicated solely to sleep tracking.

Sleep tracking compared to Fitbit

Apple Watch does track sleep. With watchOS 9, Apple introduced Sleep Stages, which tells you how much time you spent in REM, Core, or Deep sleep, along with the amount of time you were awake. It also records your heart rate and respiratory rate. However, Apple's sleep tracking does not summarise the data as well as its competitors, and it cannot diagnose sleep conditions.

Fitbit devices offer Sleep Profile, a program that analyses users' sleep on a monthly basis and assigns each individual a sleep profile that best represents their habits. The free version of the Fitbit app has basic sleep monitoring, while the paid premium subscription offers more analysis of your sleep. Fitbit Premium costs $10 per month or $80 for an annual membership.

The Fitbit Inspire 2 has been rated as one of the best sleep trackers, with its thin design, low price, and long 10-day battery life. It automatically tracks bedtimes and wake times, disturbances, sleep stages, and heart rate. The Fitbit Inspire 3 is another great option, which tracks your sleep time and stages (light, deep, REM), and records any intervals you spent awake. It also provides a sleep score and Smart Wake alarms that help optimise your REM cycles.

Compared to Fitbit, Apple's sleep tracking provides less insight and data interpretation. While Apple Watch tracks your sleep stages, it does not offer a monthly analysis or sleep profile like Fitbit. Additionally, Fitbit offers a free basic monitoring option, while Apple Watch requires a subscription to the Health app.

In summary, while both Apple Watch and Fitbit devices can track your sleep, Fitbit offers more comprehensive sleep tracking features and analysis, especially with the paid premium subscription.

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