I am thinking about incorporating a bit more treadmill running into my running program.
I have the Garmin HRM Pro and Fenix 6 which gives me power, and a approximate running speed running on a treadmill.
I have a access to a professional grade treadmill, which I set to 12 km/t - pace 5:00. I put the treadmill to 1 pct grade.
I had a run for 31 minutes. The treadmill said 6,11 km completed while the watch said 7,12 km. I used the calibration function on the Garmin Watch to correct the effort.
My HR was top Z2 - bottom Z3 which usually would equate more or less to 5:00 min/km - just as the treadmill was set on.
if the watch says 7.12km and treadmill says 6:11km and you corrected the distance after the workout, changes in Garmin Connect doesn’t affect the Raw FIT file and what gets transferred to intervals.icu is the Raw Fit File.
6.11km in 30min30s = 5.00 pace
7.12km in 30min30s = 4:17 pace
if you changed the distance within intervals.icu, did you click the “action->analyse” again?
I changed the distance when saving the workout using Garmins calibrate function. So the distance transferred from Garmin is 6.11 km. However, that does not seem to affect, that I still ran with the 4:17 pace in the intervals for the workout.
Perhaps I’m off the mark here so bear with me.
It’s unclear how Garmin’s Calibrate funcion that you mention works. It may be just changing the final “session” data from 7.11km to 6.11km but it doesn’t change any of the Per-second data that is written into the FIT file.
Intervals.icu uses the per-second data to calculate everything itself and doens’t use any of the pre-written LAP / Session data.
When I look at your orignal post (you may have linked your activity, but alas, no one can access it except for your followers), the pace is a constant ~4min/km which leads me to believe that this is exactly what is happening.
