@cfc - I don’t think this is a sensor issue. This sounds like WOD not getting a HR lock at the start of a workout. My run this morning took 10 minutes to get its first reading. I can force it by doing a heart rate read with standard app and that often forces WOD to start recording it from that point. I suspect the change you are making in the next release to display the HR lock might fix this issue for
@mindquest
Believe me it is not an issue with WOD. Getting a lock at the start of a workout has been an issue with the watch for many people ever since it was first released. If you Google it then you will see many users reporting it for other workout apps, especially the native one.
Workout apps on the Apple Watch request HR readings from watchOS and that returns the readings to the app as it gets them. The app does not do anything to get a lock. That is all done by watchOS.
The reason using Apple's Heart app to get a reading can kick start it in WOD is because the watch uses infra-red light for one-off readings whereas it uses green light for frequent readings during workouts.
Learn how Apple Watch measures your heart rate.
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Is the Color of Light in Your Wearable Affecting the Accuracy of Your Health Data? Wearables are on the wrists of millions of people today, gathering information on everything from the simple metrics of steps taken to the advanced biosignals of heart rate variability and blood oxygenation. Despite w
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The fact that you see a reading in WOD when you use the Heart app actually proves that WOD is working correctly. It hasn't stopped listening to readings from watchOS because it displays the reading produced by the infrared light. And sometimes this reading helps the watch get a lock with the green light.
In the past HR problems were the most common issues I received about the app, but it has got better and better. I still get more reports in the (northern hemisphere) Winter than in the Summer, but far fewer than I received in past years. This is despite the app having more users over time, so I assume that the latest Apple hardware and/or software is much better. However it is still a problem for some people.
The change in the next version of WOD should help such people because you will be able to wait for a lock before starting. The problem with starting first is that it is more difficult for the watch to get a lock whilst you are moving. This is especially true when running because of the jarring from your footfalls. For example it has to avoid "cadence lock" (where the sensor locks on to the steps instead of the heart rate).
This difference between activities often explains why some people only have problems with WOD but not with other apps. They use other apps for activities where it is easier for the watch to get a lock. Although that can also be explained by the fact that it just varies from workout to workout.
Note that even with the current version of the app you can always start and pause immediately and wait for a lock before resuming.