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Garmin Coach Plan Workouts Not Showing Lap Splits
When you're doing a time-based Garmin Coach plan workout (e.g. Long Run-90 minutes), you will not see lap splits at every mile or kilometer. If those splits are important to you, you can choose not to do the scheduled workout and, instead, do a simple, non-scheduled workout on your device using just the Start/Stop buttons.
The Auto Lap setting will need to be enabled. Refer to your owner's manual and search "Auto Lap" for specific steps for your device.