Related
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Ffenix 6 doesn't use HRM-TRI cadence data for measuring speed on treadmill

Ambroży Kleks
over 4 years ago

The HRM-Tri chest sensor seems to be far better in measuring cadence than the Fenix 6 wrist watch itself. Apparently, the HRM cadence data is not used by the speed measuring algorithm while on treadmill. It looks like the cadence transmitted from HRM is used only to show the cadence in post run statistics, but speed is calculated from the wrist-watch cadence sensor (accelerometer I guess) and because of the freqent errors in cadence measuring by this sensor the speed is also very inaccurate.

Does anybody know how to fix it? 

  • 0 over 4 years ago

    You need to add a foot pod for pace, RDP and HRM don't provide this measure

  • 0 over 4 years ago in reply to Luca

    Thank you for the solution. However, I would like to understand why the watch doesn't use good data from HRM. Instead uses inaccurate data from wrist sensor. Clearly, the HRM provides cadence and better than the wrist watch. There is a couple of problems caused by this. For instance, when I transmit cadence from watch to Zwift then cadence on the Zwift screen is from the wrist watch and at the same time cadence on the wrist display is from the HRM. So I see 183 on the watch and 91 or 0 or 182 on the screen. This makes the pace calculations wrong as they're computed from strides and cadence when indoor.

    It's a bug imo or maybe there is a technical problem that I don't see and this what I would like to know Slight smile

  • 0 over 4 years ago in reply to Ambroży Kleks

    Cadence alone is not enough to calculate indoor pace.

  • 0 over 4 years ago in reply to tmk2

    Obviously, it's not enough, I assume that in the simplest form it should be is (cadence x stride length)/time, but there are two things:

    1. Whatever it takes to calculate indoor pace it seems that is taken from the accelerometer and the accelerometer put on your chest provides better data than the accelerometer on your wrist. The riddle here is why the watch uses the HRM running dynamics data only to show you during the exercise but not for the pace calculation.

    2. Whatever it takes to calculate indoor pace it's strictly correlated with the wrist cadence data. Every time I put my finger on the treadmill console the pace and cadence drops to 0, because the wrist is still for a moment. Quite surprising, the watch face shows proper cadence data at the same time, because reads them from HRM.

  • 0 over 4 years ago in reply to Ambroży Kleks
    Ambroży Kleks said:
    Whatever it takes to calculate indoor pace it seems that is taken from the accelerometer and the accelerometer put on your chest provides better data than the accelerometer on your wrist.

    But it's different kind of data. Accelerations on a chest-worn sensor are different that accelerations on your wrist. I'm not quite convinced that chest accelerations are better suited for pace calculation (or if they can be used at all).

    Ambroży Kleks said:
    Whatever it takes to calculate indoor pace it's strictly correlated with the wrist cadence data.

    Yes, but cadence is only one of many other data needed to calculate pace. If hold your hand on the console, then not only cadence is missing. All the other raw acceleration data is missing as well. And while cadence data in theory could be replaced by cadence comming from another sensor, there is no way to replace the other acceleration data.