The training effect of a strength activity shown in the watch is usually incorrect. For example, I got strange values like anaerobic and tempo for a soft session. I think the displayed value corresponds to the trainning effect of the last running activity. In any case, when the strength activity is uploaded, the training effect changes in Garmin Connect, which shows a more accurate value.
This is happening for a couple of months, and I am sure it is a bug introduced in any of the latest firmwares, because I hadn't seen this behaviour before.
