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Track Your Sleep With the Apple Watch


I share my bedroom with at least one person, sometimes two or three depending on whether any children migrate during the night. So I feel like I have a superpower when I wake up and silence my alarm five minutes before it actually goes off. I’m not super, of course: it’s just a silent alarm on my Apple Watch.

The silent alarm helps me get up for my early morning workouts, and the fact that it can track my sleep means I can keep tabs on whether I’m getting to bed early enough each night. You don’t need to track sleep each night, but a tracker like the Watch or a Fitbit can help you tell, automatically, whether or not you’re consistently getting enough.

There’s another small advantage to sleeping with a tracker that can measure heart rate: you get a true resting heart rate. Your heart rate is lowest when you are truly resting: not sitting up, not walking around, not finishing a workout, but when you’ve been lying in bed without moving for a few minutes. (It’s also tricky to measure it first thing in the morning if the first thing that happens is that an alarm rings, scaring the bejeebers out of you.)

Knowing your resting heart rate is, again, not necessary but a nice-to-have: as you exercise and get fitter, your resting heart rate will decrease. If you’re stressed by a medical condition or by too much hard exercise, your resting heart rate may tick back up.

To get the benefits of sleep tracking and silent alarms, you’ll have to set up a few things first.

Charge Your Watch While You Shower

Finding time to charge the Apple Watch is your first issue to sort out. Unlike Fitbit models that can run for seven days on a charge, Apple figures the Watch’s battery will last 18 hours if you check the time 90 times, get 90 notifications (this is too many), and work out for an hour with music playing through the watch. It takes two hours to fully charge the battery, but you get the first 80 percent of the charge in 90 minutes.

The best time to charge the battery is twice a day, morning and evening. I keep my charger in the bathroom and set my watch to charge while I take a shower, right after my morning workout. I leave it there while I get dressed, pack my kids’ lunches, and do all my other puttering-around morning things. I put it on when I leave the house. Then I do another charging session in the evening. Forty to 60 minutes twice a day, and you’re covered.

Put Your Watch in Theater Mode While You Sleep

The Apple Watch thinks it’s so smart. It turns on when you look at your wrist, which is handy sometimes but lights up the room if you’re anything but still when it’s dark. Fortunately, there’s a quick setting to stop this.

Swipe up from the bottom of the watch, and one of the control center buttons has little happy and sad mask faces. This turns on Theater Mode. In Theater Mode, the screen will stay dark unless you tap on the face or push one of the buttons. Notifications are also silenced, but alarms will still buzz you on schedule.

Turn off Cover to Mute

There’s one more pitfall. The handy “Cover to Mute” feature allows you to silence notifications by putting your hand over the watch face. When your watch vibrates to wake you up, it can be silenced this way, too. So you can turn off your alarm without realizing it.

There’s no handy control center button for this. Go into the Apple Watch app, and find Cover to Mute under the Sounds & Haptics settings menu.

Choose a Good Sleep App

I like Sleep Watch, which tracks your sleep automatically and gives you some handy stats each morning. When you look at your stats, it asks you how rested you felt when you woke up, which is honestly a better measure of sleep quality than any of the data points it can track electronically.

For an alarm, I just use the Watch’s built-in alarm feature.

Sleep++ and Pillow keep simpler stats, meaning your eyes are just on your sleep time (good) and your “sleep quality,” which is unreliable in any app. Pillow also has a “Smart Wake Up” alarm, which aims to find your lightest sleep within 30 minutes (or your choice of 15 to 60 minutes) before your alarm time. Other alarms will not go off while Pillow is tracking your sleep, so choose well.

If you already use Sleep Cycle on your phone, you can use it with your watch too, but it still expects your phone to be on your bedside table listening with the microphone. (The Watch feature adds the ability to monitor heart rate, but you need to pay for a premium subscription to use it).