With MXActivityMover it is possible to transfer your Garmin Connect / Polar Personaltrainer activities directly to Movescount.
It is possible to transfer a single activity directly by id (Garmin / Polar) or by file upload (Garmin).
Purchasing the full version will provide you the possibility to upload multiple activities at once. You can restrict the result by start time (from/to).
The transfer is logged in a protocol so you can see which activities were already transfered, you can use this to get a kind of delta mechanism.
If you wish a link to the original Garmin Connect / Polar Personaltrainer activity is also added in the notes field of the transfered Move.