Apple Watch Can Accurately Predict Stress Levels, Study Shows

The Apple Watch can accurately predict stress levels, according to a study conducted by researchers at the University of Waterloo, Canada (via MyHealthyApple).

apple watch ecg wrist
Using the Apple Watch Series 6's ECG sensor, the researchers found that there was a close association between ECG data, including heart acceleration and deceleration capacity, and participants' reported stress levels at the time the readings were taken. Machine learning algorithms were then developed using this information to create a prediction model.

The stress models are said to have a "high level of precision," but lower recall. The study concludes that the Apple Watch has "promising" potential for stress prediction, and proposes that since the device collects additional health information such as sleep and activity information, even more data points could be integrated into stress models to increase their predictive accuracy.

The researchers postulate that the Apple Watch could be used to aid mental health care, offering activities such as breathing exercises to offset stress signals, responding early to changes in mental health. Competing devices from Samsung, Fitbit, and Garmin have offered a stress score feature for some time, but Apple has yet to implement such a feature in its Health app.

Tag: ECG
Related Forum: Apple Watch

Top Rated Comments

Shasterball Avatar
18 months ago

Mine has been quite low for a while and I’ve been trying to raise it but it’s stubbornly staying low. What type of things did you do? I’ve done all the usual recommendations.

I would talk to a doctor, not someone on MacRumors :)
Score: 16 Votes (Like | Disagree)
appleguy123 Avatar
18 months ago
Highly recommend everyone track and try to increase their heart rate variability. It is directly related to the ability of the brain and heart to handle stress and is a biomarker for autonomic nervous system function. I started working on mine in May and I really feel 3x better and more resilient day to day. The Apple Watch has been tracking this in the background for as long as you have been wearing it. You can take in the moment HRV measures (which is very similar to what this study did) by using the breath app and then checking the health app.

This is one of the most important health metrics it tracks. Another good one related to mental and physical health is “cardio fitness” which is tracked every time you log a walking or running workout. This is a direct measure of how much blood your heart can get to your brain.

Attachment Image
Score: 12 Votes (Like | Disagree)
fatTribble Avatar
18 months ago
Pfft! My mood ring in the 70s could do that! ?
I know it worked too because it turned red when I lost my pet rock.

Score: 6 Votes (Like | Disagree)
ponzicoinbro Avatar
18 months ago
I'm getting too old to feel stress. I'm just like 'Oh app crashed. Oh back hurts. Oh people are fighting again'.
Score: 6 Votes (Like | Disagree)
appleguy123 Avatar
18 months ago

May I ask, how did you improve you hrv that much? What kind of workout would you recommend?
My specific HRV routine. You can see my results because I researched this extensively but its definitely not medical advice.

-3-5g fish oil with at least 200IU vitamin E. Taken with food each day.

-Walking/Running for 1 hour every day (I only started this in September you can see how it really helped HRV, but it’s not the whole picture). I just try to spend 11-20 minutes per day in the max heart rate zone.

-Reduce intake of caffeine and other stimulant drugs that increase the heart rate.

-Increase intake of antioxidant foods.

-Be diligent about mindfulness. You don’t need an app necessarily but I used Headspace. Making sure you aren’t constantly bogged down by negative thoughts is very important for this reflex and for life itself.
Score: 6 Votes (Like | Disagree)
TheOldChevy Avatar
18 months ago
That's an interesting feature. I am not sure a unified medical definition of stress exists, but still, that would be an interesting indicator.
Score: 5 Votes (Like | Disagree)

Popular Stories

iOS 17

Troubling iOS 17.5 Bug Reportedly Resurfacing Old Deleted Photos

Wednesday May 15, 2024 5:29 am PDT by
There are concerning reports on Reddit that Apple's latest iOS 17.5 update has introduced a bug that causes old photos that were deleted – in some cases years ago – to reappear in users' photo libraries. After updating their iPhone, one user said they were shocked to find old NSFW photos that they deleted in 2021 suddenly showing up in photos marked as recently uploaded to iCloud. Other...
General Apps Messages

iMessage Down for Some Users [Update: Service Restored]

Thursday May 16, 2024 3:00 pm PDT by
The iMessage service that Apple users to send messages to one another appears to be down for some users, and messages are failing to go out or are taking an extra long time to send. There are numerous reports about the issue on social networks and a spike of outage reports on Down Detector, but Apple's System Status page is not yet reporting an outage. Update: Apple's status page says...
CarPlay Sound Recognition

Apple Previews Three New CarPlay Features Coming With iOS 18

Wednesday May 15, 2024 9:18 am PDT by
Apple today previewed new accessibility features coming with iOS 18 later this year, and this includes some new options for CarPlay. Apple highlighted three new features coming to CarPlay: Voice Control: This feature will allow users to navigate CarPlay and control apps with just their voice. Color Filters: This feature will make the CarPlay interface visually easier to use for...

Hands-On With the New M4 OLED iPad Pro

Wednesday May 15, 2024 10:40 am PDT by
Today is the official launch day of the new iPad Pro models, and these updated tablets mark the biggest feature and design refresh that we've seen for the iPad Pro in several years. We picked up one of the new 13-inch models to check out everything new. Subscribe to the MacRumors YouTube channel for more videos. When it comes to design, Apple is still offering 11-inch and 13-inch size options ...
iphone 15 pro max vs iphone 16 pro max

iPhone 16 Pro Max Looks This Much Bigger Beside iPhone 15 Pro Max

Thursday May 16, 2024 4:51 am PDT by
This year's upcoming iPhone 16 Pro Max is expected to get a boost in overall size from 6.7-inches to 6.9-inches, and a new image gives us a good idea of how the current iPhone 15 Pro Max compares to what could be Apple's largest ever iPhone. The image above, posted on X by ZONEofTECH, shows a dummy model representing the ‌iPhone 16 Pro‌ Max alongside an actual iPhone 15 Pro Max. Dummy...
Delta Hands On Feature

iPhone Emulators on the App Store: Game Boy, N64, PS1, PSP, and More

Thursday May 16, 2024 12:45 pm PDT by
In April, Apple updated its guidelines to allow retro game emulators on the App Store, and several popular emulators have already been released. The emulators released so far allow iPhone users to play games released for older consoles from Nintendo, Sony, SEGA, Atari, and others. A list of some popular emulators available on the App Store so far follows. Released Delta Delta is...