Image source: Twelve South

Apple Watch’s alternative approach to heart rate tracking on the upper arm

A recent observational study has shed light on the potential of the Apple Watch to monitor heart rate from an unconventional site: the upper arm.

Published in the journal JMIR Human Factors, the research actually focused on surgeons. They operate under immense pressure, where every heartbeat counts—not just for the patient, but for the surgeon as well. But the findings also have implications for the rest of us.


The study – methodology and findings

The study’s methodology was straightforward yet robust. Researchers employed two identical Apple Watch Series 8 devices to monitor the heart rates of surgeons performing robotic-assisted surgeries. One device was traditionally placed on the wrist, while the other was secured to the upper arm. This is a novel approach aimed at circumventing sterility constraints. Heart rate data were meticulously gathered from both devices simultaneously.

The study’s results were promising. The mean absolute error across all participants was a mere 3.63 beats per minute (bpm). Individual individual errors ranged from 2.70 to 4.28 bpm. The mean absolute percentage errors were similarly low, between 2.42% and 4.58%.

In plain English, these figures suggest a high degree of accuracy in the Apple Watch’s heart rate readings when worn on the upper arm. Bland-Altman plots corroborated these findings, showing no systematic error in the heart rate measurements between the upper arm and wrist locations.

Essential readingTop fitness trackers and health gadgets

Presumably, if the latest Series 9 was used in the study the results would have been even more encouraging. Regardless, these findings suggest that the Apple Watch can reliably monitor a surgeon’s heart rate from the upper arm. Which offers a practical solution to the challenge of maintaining sterility. This could pave the way for better management of surgeons’ physical and mental demands during operations, ensuring their well-being is monitored with the same rigor as their patients.


Implications for the rest of us

For the wider population, the implications of this study extend to everyday use. They suggest that the upper arm can serve as a viable alternative site for heart rate monitoring with devices such as the Apple Watch. This newfound flexibility not only augments the functionality of the device but also broadens the ways in which we can integrate wearable technology into our health and fitness regimes.

Apple Watch Upper Arm
Image source: Twelve South

When you’re engaged in activities where wrist-worn devices may be obstructive, or you’re simply seeking a more comfortable fit, there are solutions available. A variety of bands and mounts specifically designed for upper arm placement are readily accessible on various retail platforms, offering a multitude of options to customize how you wear your Apple Watch.

As an example, a popular option on Amazon is Twelve South ActionSleeve. Reasonably priced, it comes in the form of a strap for the upper arm. The Apple Watch rests in a built-in bumper which helps shield it from nicks and dings while allowing crown access. Something like this might be useful for activities such as HIIT, Kettleball training and more.

Like this article? Subscribe to our monthly newsletter and never miss out!

Marko Maslakovic

Marko founded Gadgets & Wearables in 2014, having worked for more than 15 years in the City of London’s financial district. Since then, he has led the company’s charge to become a leading information source on health and fitness gadgets and wearables.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.