Missing manual - Training Load, .estimatedWorkoutEffortScore, .workoutEffortScore - Where are the Apple RPE CR-10 scale docs?

Apple is using the RPE scale for workout effort scores. This stands for the Rate of Perceived Exertion. They're specifically using the CR-10 scale, at least from what I can tell by saving values to HealthKit. They only accept value between 0 and 10.

Has anyone been able to find a scientific or academic paper on how they have chosen their different effort breakouts?

Right from the Fitness app on iPhone and Activity app on Apple Watch:

  • 1-3 Easy
  • 4-6 Moderate
  • 7-8 Hard
  • 9-10 All Out

There is zero documentation on these new types, which makes it difficult for workout recording apps to properly and appropriately save this new data type. Sure, we can use the Apple apps as a reference, but since there isn't a built-in Apple SwiftUI sheet to present this data, and no references to academia to point our users to, our solutions would just look the same.

FB15315876 - Documentation / HealthKit: Publish documentation about .workoutEffortScore and .estimatedWorkoutEffortScore

FB15316109 - Documentation / HealthKit: Add documentation to .estimatedWorkoutEffortScore and .workoutEffortScore that you can't save those samples via the save API and that they must be related and let that API save the sample

FB15316251 - Documentation / HealthKit: Add documentation for acceptible values of .estimatedWorkoutEffortScore and .workoutEffortScore - don't rely on a runtime error!

Apple missed making an enum for all third party developers this year.

Missing manual - Training Load, .estimatedWorkoutEffortScore, .workoutEffortScore - Where are the Apple RPE CR-10 scale docs?
 
 
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