Short answer: you usually cannot edit the original Apple Watch workout distance in place. The practical workaround is to save a corrected workout copy to Apple Health, then delete the original workout in Apple Fitness if you want clean totals.
Why Apple Watch workout distance is hard to edit
Apple Health stores workouts as structured HealthKit data. A saved workout can include distance, duration, energy, heart rate samples, route data, laps, events, and metadata. For privacy and data integrity reasons, third-party apps do not get a simple "change this workout distance" button for the original Apple Watch workout.
That matters most for treadmill runs and indoor walks. If your treadmill says 5.00 km and Apple Watch saves 4.62 km, the incorrect distance affects pace, splits, and weekly totals.
What you can do instead
- Open Fix My Treadmill and choose the Apple Watch Indoor Run or Indoor Walk.
- Enter the real treadmill distance shown on the machine.
- Review the corrected pace and splits.
- Save a corrected workout copy to Apple Health.
- Open Apple Fitness and delete the original workout if you do not want two entries.
Should you delete the original workout?
If you keep both workouts, Apple Fitness may show both entries and your totals can be counted twice. If you want a clean history, delete the original Apple Watch workout after confirming the corrected copy looks right.
When deleting in Apple Fitness, choose the option that removes the workout entry without deleting unrelated Health data unless you are sure that is what you want.
What changes in the corrected copy?
Fix My Treadmill recalculates distance-based values such as pace and split timing from the corrected distance and the original workout duration. Heart rate and calories are preserved where HealthKit allows it instead of being guessed from the new distance.
What does not change in place
The original Apple Watch workout remains a separate Health entry. Fix My Treadmill does not silently overwrite it, because the correction workflow is built around saving a new corrected copy. That makes the result easier to review: you can compare the original distance with the real treadmill distance, check the corrected pace and splits, and only then decide whether to clean up the original workout in Apple Fitness.
This matters for totals. If both entries remain in Apple Fitness, weekly distance and workout history can show both workouts. For a clean history, confirm the corrected copy first, then delete the original Apple Watch workout if you no longer want the inaccurate entry.
When a corrected copy is the right answer
A corrected copy is useful when the treadmill or indoor bike distance is the value you want in your Health history. It is especially useful after indoor runs, indoor walks, or indoor cycling sessions where the machine and Apple Watch disagree. The app is focused on that cleanup task: choose the workout, enter the machine distance, review the result, and save the corrected Health workout.
The correction flow stays local to your iPhone and Apple Health permissions. The app needs permission to read workouts and related Health metrics, and permission to write corrected workouts back to Apple Health. It does not require an account wall for the workflow.
More guides
- How to fix wrong Apple Watch treadmill distance
- Why Apple Watch indoor run distance can be inaccurate
- All guides
Try it: Fix My Treadmill includes 3 free fixes, then offers a one-time unlock for unlimited corrections. Download it on the App Store.