Apple Watches are known for their reliable heart rate monitoring capabilities, but there seems to be a problem with the top model “Ultra” specifically designed for athletes. Some users have reported that their Ultra models are not accurately recording heart rate during workouts. This issue is particularly noticeable at the beginning of a training session, where the Ultra briefly displays the heart rate and then shows a gray screen. It takes over 10 minutes for the measurement to resume, and this pattern continues throughout the workout.
This problem is most evident in running and cycling workouts, where sudden changes in heart rate can disrupt the measurement. Training according to heart rate zones, a key feature of watchOS 9, becomes virtually impossible with the Apple Watch Ultra. Furthermore, the recorded data after the training session is also missing, which affects the accuracy of derived information such as training load.
Users have been reporting these problems since the introduction of the Apple Watch Ultra, with some attributing it to temperature changes and others experiencing it even in summer heat. However, Apple support seems to be unaware or dismissive of the issue. Basic troubleshooting steps such as reconnecting or reinstalling the Ultra have not helped, and software updates have not fixed the problem either.
The extent of this issue is unknown, but it has been observed in two out of four Apple Watch Ultras in the Mac & i editorial team. This indicates that it is not a user or wrist-related problem, as both watches were used in the same way by the same person. It remains to be seen how Apple will address this issue and provide a solution for affected Ultra owners.
