Resolving Heart Rate Discrepancies Between HRM Plus, Peloton, and Garmin Connect

I've noticed a significant discrepancy between the heart rate data recorded by my HRM Plus, which is connected to my Peloton and synced back to Garmin Connect, and the data directly from Garmin Connect, which is consistently lower. Even during an activity with the HRM connected, the optical heart rate sensor on my Fenix 6 seems to produce readings that are noticeably off compared to the HRM Plus.

It also seems that if I’m not actively recording the workout on my Fenix 6, the HRM Plus data isn't utilized, which adds to the inconsistency.

Do you have any advice on how to ensure the heart rate data remains consistent across devices and platforms?

  • In my experience, the Fenix watches do a decent job of measuring HR but aren't as fast to respond as a chest HRM. If I'm doing any sort of intense exercise, particularly with rapid changes like interval sessions, I'll wear a chest HRM. 

    Some folk seem to get much worse results with a watch HRM anyway - a combination of fit, movement and how hairy your arms are (and, after all, you're a monkey Joy)

  • It also seems that if I’m not actively recording the workout on my Fenix 6, the HRM Plus data isn't utilized, which adds to the inconsistency.

    Yes, that's exactly how it is designed to work. HRM-Pro is used only during activities, or when you do not wear the watch, and the strap is on (and paired to Garmin Connect on the phone!).

    Do you have any advice on how to ensure the heart rate data remains consistent across devices and platforms?

    Either start an activity on the watch (while having the strap paired to it), or remove the watch from your wrist. You can discard the activity at the end, if not needed, and you prefer keeping the activity data from Peloton.

    However, the all-day HR graph will never be identical top the graph from the activity, since the all-day graph shows 2 minute samples (averages over 2 minutes), while the activity has up to 1s HR samples. Hence any short peaks or drops of the HR will be smoothed out from the all-day HR graph anyway.

  • Yeah my experience of the fenix watch HR monitor is way off, when I am doing serious training I do not trust it. 

  • Thanks. I have noticed that the fenix get super excited when I trail run and HR on fenix watch shoots up to 160/170 and I know for a fact it is probably around 135.

  • I have noticed that the fenix get super excited when I trail run and HR on fenix watch shoots up to 160/170 and I know for a fact it is probably around 135.

    It will not happen if you do as I suggested. What you observe is the cadence lock, which is a common problem of all optical HR sensors. Pair the HRM strap to the watch, start an activity, or use the strap paired to the phone, standalone, and you'll be fine.

  • Ah that is super interesting, thats why I should also use my chest strap, especially when training.