Garmin allows runners to set an autolap. If you setup autolaps with your Garmin watch, and you have a watch that allows pace and distance from Stryd while GPS remains enabled (such as a Garmin FR935XT), the distance for the autolap always comes from GPS and never from Stryd distance.
When data from Garmin Connect gets imported into PowerCenter, you can see your Garmin lap information in PowerCenter (under Splits). Since a new lap was marked by the GPS distance, it will differ slightly with the distance recorded by Stryd.
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