If you've modified an individual run (like adjusting the target paces or changing the run type) and want to undo it, you can easily revert back to your original plan.
Open the modified run to view its details.
Tap the Reset changes icon in the action menu. (Note: This icon only appears if you have made adjustments to the session).
Tap Yes, reset changes to confirm.
Your session will instantly revert back to its original target paces and structure.