Your Apple Watch could be a stress-tracking tool

A photo of the heart rate screen on the Apple Watch
(Image credit: Future/Tom's Guide)

Unlike some other wearables, the Apple Watch doesn't explicitly support stress-tracking features that can alert you to potential changes in your stress level. But a new report suggests that Apple's smartwatch has the tools in place to one day support that capability.

The study, published in Frontiers in Digital Health (opens in new tab), was conducted by researchers at Canada's University of Waterloo collecting electrocardiogram (ECG) data from assorted Apple Watch Series 6 models running the Apple Watch ECG app. That app uses a sensor on the watch to record the timing and strength of your heartbeat, so that it can detect things like atrial fibrillation.

But researchers say that data can also be employed to predict stress levels, with a 30-second ECG reading providing feedback on a watch wearer's stress levels. And the study, first spotted by MyHealthyApple (opens in new tab), found some promising results with existing Apple Watches that could be fine-tuned in the future.

"We found that the models performed at the low end of the state-of-the-art stress prediction technology," the report on the Apple Watch's stress predicting capabilities concluded. "We were able to identify several [heart rate variability] features, as well as socio-demographic classes which impacted the accuracy of the model. The results suggest that, with further development, Apple Watch ECG sensors could be employed for mobile, real-time stress prediction."

Currently, Apple Watches can effectively predict "no stress" relatively well, the study adds. What needs to be developed are features that would provide more accurate predictions for potential stress.

Stress tracking has been floated as a possible feature for both the Apple Watch and the watchOS software that powers Apple's wearables for some time. At the same time, rival devices — notably the Samsung Galaxy Watch 4 and Fitbit Sense 2 — offer stress monitoring features of their own. So that's a potential gap that Apple might look to close. The Apple Watch 8, for example, added a skin temperature sensor, and some have speculated that sensor could contribute the metrics needed to accurately measure stress.

As to the timing of such a feature, only Apple knows what updates like this year's Apple Watch 9 and watchOS 10 might deliver at this point, but it's no secret the company sees health tracking and alerts as a key selling point for its smartwatch. 

With the University of Waterloo research suggesting that current Apple Watches already have some tools in place for stress tracking, this is a potential addition worth keeping an eye on as more Apple Watch rumors start to circulate in the new year.

Philip Michaels

Philip Michaels is a Managing Editor at Tom's Guide. He's been covering personal technology since 1999 and was in the building when Steve Jobs showed off the iPhone for the first time. He's been evaluating smartphones since that first iPhone debuted in 2007, and he's been following phone carriers and smartphone plans since 2015. He has strong opinions about Apple, the Oakland Athletics, old movies and proper butchery techniques. Follow him at @PhilipMichaels.