Soccer/Football with HRM Pro Plus: Wrong usage of Data Source

I use my Garmin Forerunner 965 and HRM Pro Plus strap to record my football training as it is intended for team sports:

I start the soccer activity (checked for indoor and outdoor) with my strap connected to my watch (ant+) and leave the watch in the changing room (it is not allowed to wear a watch during training/matches).  When I’m finished, I come back and stop the activity and it backfills the data from the strap to the watch, which works well for hearth rate. 

After syncing, the activity looks like this:




Obviously, it uses the watch for the Speed and Respiration metric. 
Why is that? I understand that the Speed metric is hard to do if you only have the accelerometer of the strap, but this is the case even if I try to force it to use that via the „indoor“ setting. I don’t know why it would use the watch for respiration either, when there is almost no data. 

How I think one could solve that:

If is is hard to determine speed because of inherently different stride lengths in football, at least give me a reading about the number of accelerations or sprints that I did. 

Or do I completely miss something here? I suppose other teamsport users have the same issue as me, where the data from the watch is used instead of the strap. 

  • Did you does HRM sensor calibration like it is described in manual.
    I never use my HRM-PRO that way but respiratory data also should be recorded by strap.
    When you calibrate sensor, also distance and speed might be estimated based on data from the strap, but this is only my guessing.

  • According to the HRM Pro Plus manual, if you start an activity and use your HRM so that it's not connected to the watch, only heart rate data is stored in the strap and later transmitted to the watch. (And even this they only mention under "Heart Rate While Swimming", but I suppose it works for any activity).

    Respiration rate is analyzed by the watch from the real-time HRV data sent by the strap, and the strap does not store HRV data for to be downloaded later. And, as you suspected, I also think that speed would be really difficult to estimate from acceleration only in football. It's different in treadmill running etc, which are steady state efforts (so that you can analyze acceleration patterns over time).

  • Thanks for your input about the respiration rate, I wasn’t aware that it only uses the real time HRV data. 

    In the manual, there is also a point about activity tracking where it says that if you only wear the strap that it also counts steps and syncs it later to Garmin Connect or a Garmin Device.

    So I infer from that, that there is some kind of accelerometer data transfer/storage happening.

    It’s a bit frustrating that it could be much more useful for team sports with better software implementation.  

  • I will have to wear it for longer to properly calibrate it for running, although I don’t expect it to really be useful for team sports since there is no consistent stride length and it is unlikely that it is even stored on the device (see Bittis comment). 

  • The HRM Pro+ does count and store 24/7 steps and hr (just like the watch), and those are combined with the watch's 24/7 data by Physio TrueUp.

    (And yes, the strap has an accelerometer, which is also used for measuring running dynamics.)

  • I don’t expect it to really be useful for team sports since there is no consistent stride length

    Completely agree.
    Nice that you are aware this limitation.
    Wish you luck with it.