Recently completed a row on my Concept2 rower which recorded my heart rate. After synching the data to Garmin Connect, my workout summary shows 90% of the workout (~45 minutes) was either in Zone 3 or 4 (split about evenly). Despite this my Intensity Minutes is still at 0. Will the external data imported to Garmin not count (i.e. does it need to be logged from the Vivoactive 4)?
So far when rowing I have found the HRM on the watch to be inaccurate which led me to purchase the chest strap. For instance when my heart rate was at 140 on the strap, the watch was showing 79 (I did not have an activity running on the watch).