Did anybody successfully calibrate HRM-Pro manually?

By this I mean you have performed a manual treadmill calibration and the following runs were accurately measured.

I tried to manually calibrate an HRM-Pro and it didn't work. After calibration, the distance was still off, and worse than before manual calibration.

https://support.garmin.com/en-US/?faq=8B0cpkix4E8kJHHhs2OzY6

Here what I did:

- ran outdoors with HRM-Pro set to indoors both for pace and distance for more than 2 hours, auto-calibration turned on, Stryd pod disconnected

- on a track, selected treadmill activity, HRM-Pro set to always for pace and distance,

- ran 2000m, calibrate and Save, input 1.24mi

Initial distance about 1.26mi (1.6% off - not too bad) was uploaded to Strava (known bug/issue)

Calibrated correct distance eventually saved to Connect, and, in theory, to the HRM-Pro directly

- after manual calibration, left HRM-Pro to always provide pace and distance, started a track run activity. After one loop of 400m, I was expecting the distance to be accurate, but no, the reported distance was 370m (8.5% difference)

- I thought maybe there was different algorithm from treadmill. So I ran another 400m with a treadmill activity, using the calibrated HRM-Pro, and instead of 0.25mi (0.2485mi), I got 0.21mi! (13% too short!)

Finally, for comparison, I turned off the HRM-Pro pace and distance, and switched to Stryd pace and distance. I ran a 400m loop and got exactly 400m

Top Replies

mleonc92 10 months ago +2

You are not taking into account that, at least with Stryd and probably with the HRM Pro too, Garmin don't take into account the distance that you run the first 3-4 seconds. I've done several testings…
kerlaz over 2 years ago +1

I find the pace from HRM Pro useless despite following the calibration steps. Always out by around 30-40 seconds per mile.

forums.garmin.com/.../pace-discrepancy-when-using-hrm-pro-for-pace
trux over 2 years ago in reply to AlbertoGaMo +1

AlbertoGaMo said:
Just to be sure if I have understood you well. You use the HRM-Pro with the option indoor, running outdoors and it improves the distance accuracy?.

Yes, exactly. As I wrote, the "indoor…

All Replies

0 mleonc92 10 months ago

You are not taking into account that, at least with Stryd and probably with the HRM Pro too, Garmin don't take into account the distance that you run the first 3-4 seconds. I've done several testings exporting the fit file to a Excel and I always lose around 15m after a Start with the Stryd Wind and around 7m with the Stryd Next Gen. Also, when you Stop the Activity, you do gain -out of nothing- around 5m. That and the fact that the watch round the distance to a decimal, makes it quite hard to actually measure something.