Apple is playing it safe when it comes to expanding the Apple Watch’s health-tracking capabilities. The two temperature sensors of the Apple Watch Series 8 and Ultra are therefore limited to the subsequent estimation of ovulation, when they could do much more. The same is true for stress, according to researchers at the University of Waterloo, Canada.
Study participants received an iPhone 7 with iOS 15 and an Apple Watch Series 6 with an embedded ECG app. For two weeks, they performed an electrocardiogram with the watch six times a day at about three-hour intervals. To complement this data, the guinea pigs also completed a stress questionnaire via a specially developed iPhone application.
The researchers theorize that the data collected from the Apple Watch’s ECG can be used to predict stress. “Users performed a non-invasive 30-second electrocardiogram and received immediate feedback on their stress level,” they said. Heart rate variability (HRV) in particular has come into focus as this metric can actually be used to measure stress levels.
A predictive model was developed using a machine learning algorithm fed with HRV data. This results in “high precision” stress measurements, but the researchers believe the Apple Watch can further improve things by tapping into the additional information it regularly collects, such as activity, physical activity and sleep.
In other words, Apple has everything it takes to create an accurate and efficient stress tracker. For now, though, we’ll have to settle for the mindfulness app and its reminders (regardless of the user’s state) to relieve stress. Or check out third-party apps like Stress Monitor for Watch to get a picture of his anxiety levels.
Apple lags behind the competition in this area. As the MyHealthyApple page reminds us, Fitbit and Garmin offer “stress scores” with their products, which are calculated in particular from the HRV.