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# Why is a workout timestamp weeks in the past?

Workout timestamps reflect **when the activity was originally performed, not when it was synced**.

Third-party apps can write historical workouts into Apple Health at any time, and the SDK picks them up on the next sync, so a payload can carry an old date.

To confirm, the user can **check the Health app's 'Added to Health' date** for that workout, which shows it was written late.