Apple is pushing for you to take its watch to bed with you.
It may not feel natural for everyone, but wearing the Apple Watch during sleep will be the key to unlocking the benefits of the company's forthcoming Vitals app for Apple Watch, as we learned in an interview with Apple's VP of Health, Dr. Sumbul Desai.
Apple has always been serious about health. Not only does the company own the mega-popular Apple Watch and run the Health app, a digital folder holding the wealth of information your devices collect, but Apple has ongoing research into key areas of health and trends across the population.
All of this is coming together in Vitals -- a daily overview of the health metrics the Apple Watch collects (sleep information, heart rate, skin temperature, respiratory rate and blood oxygen) when your body is at its resting state and metrics may be most telling.
If two or more health metrics or "vitals" are a little out of whack for what's typical for you, Vitals will let you know. To build out this feature, Apple used data from its own Heart and Movement study and clinical guidance for messages or alerts to deviations that may need more context, according to Desai.
"So much of your health is invisible," Desai told CNET. "This daily health status is almost like a little bit of a snapshot of your health overnight."
To take that picture, and perhaps also to compete with the smart ring boom and the relative ease of sleeping with a smart ring versus a smartwatch, Apple is making a play to be your sleep companion of choice. Here's how it will work.
Why Apple wants you to wear your watch to bed
The "biggest behavior change" most Watch users will have to make to get the most out of Vitals, according to Desai, is to go to bed with it. Tucked safely away from daytime stress, activity and movement that can influence health metrics like heart rate or temperature, health information collected overnight can give you a more complete picture of your baseline or "basal" state, according to Desai.
"To make your Apple Watch data work for you, you'll need to sleep with it," Desai said.
An example of what Vitals will show you if your metrics are outside what's normal for you.
While some people may already sleep with their Apple Watch if that's their chosen device for sleep tracking, a smartwatch like Apple's may be less appealing for sleep for some people than a less heavy wearable like the Oura Ring. The latter has led the smart ring boom, which only continues to grow with the recent launch of the Galaxy Ring.
People who are familiar with the Oura Ring may notice that Vitals sounds similar to the Oura's Readiness Score, which is meant to help prepare people for the day ahead with recommendations based on their own health information. Fitbit, another popular sleep tracker, has a similar feature. Apple's Vital app won't provide a specific value or a score, as the goal is to show "how you compare to baselines," Desai said. "We compare you against you."
In addition to closing in on sleep and relying more heavily on information collected during a rest state, the Vitals feature is a more holistic and quick way to view information Apple has been collecting all along. Desai said it may also help you when interpreting training load, another feature Apple announced with the release of WatchOS 11. Training load uses data such as your heart rate, pace and elevation to score which type of effort you're putting in.
"There's never been a better time to sleep with your Apple Watch," Desai said.
An Apple notification a day keeps the doctor away?
If there are two or more deviations in your health data -- meaning it's off compared to what's "normal" for you -- you'll be given a message letting you know, along with some context of what could be causing those deviations.
Drinking alcohol and being in the post-ovulation part of your menstrual cycle can raise your temperature, for example. Decreasing your caffeine intake or taking medications may affect your sleep duration or heart rate, as another example. Other common life experiences, like being sick or traveling to a higher elevation, may also affect the subtle data collected by the Apple Watch.
This is all to say that everyone's health data and the individual factors that feed this data should be taken in context, and Vitals isn't meant to be a feature that'll send you to the doctor willy-nilly, according to Desai. Each notification is based on information that's been observed in Apple's ongoing Heart and Movement Study, conducted in partnership with the American Heart Association and Harvard's Brigham and Women's Hospital, and collected from users who need to voluntarily join through the Research App. Population information from Apple users helped inform Vitals, along with a layer of clinical expertise, for "when these metrics are off and how often they're off," Desai said.
"We don't say, 'You need to go talk to a doctor,'" she added, referring to the language used on Vitals. "We're really thoughtful about not unnecessarily queuing you to go to the doctor."
In addition to Apple's years-long initiative studying cardiovascular health and activity, the company has two more studies, also on public health topics that overlap with features the Apple Watch can partly track: hearing health (Apple Watch has noise notifications for when things may be too loud) and reproductive health (Apple Watch can retrospectively identify ovulation since temperature rises very slightly in the second half of a menstrual cycle).
It's not an exceptionally new concept to wearables, but the Vitals feature is the latest initiative from Apple that aims to put individualized information in a broader, quantifiable health context.
"We thought through really carefully, when do we want to notify you, and how do we want to notify you," Desai said of the message system behind Vitals.
"We want to make sure when we notify you it's for a meaningful reason and it's actionable."