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

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Top Rated Comments

Shasterball Avatar
33 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
33 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
33 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
33 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
33 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
33 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)