Garmin Fenix HRV vs Polar H10 HRV – study shows the winner
Science: ResearchGate via @DrSianAllen
Thanks: @Rui
A recent study using Bland Altman plots visually shows how much more accurate a Polar H10 is at measuring RR beats during sub-maximal exercise compared to the optical OHR (Elevate Sensor, previous generation) on a Garmin Fenix 6. It would be interesting to see if the figures for the ECG-capable Fenix 7 Pro’s Gen 5 Elevate sensor are better.
Unsurprisingly the medical-grade device appears to be the best (OMNI). A second conclusion might be that chest straps are more accurate than optical HR on the wrist…but you already knew that.
More Info
RR Beats are the timing from one heartbeat to the next. HRV refers to a multitude of statistical calculations that can be applied to such RR data. SDNN and rMSSD are two HRV calculations you might know. These charts indicate HOW inaccurate your HRV MIGHT be at a sub-maximal level of effort but inaccuracy/accuracy whilst at rest faces different issues, ie we can’t infer the performance of RR recording at lower levels from thse results.
- Zephyr – here
- Equivital – here
- Infinium Medical (OMNI) – here
- Empatica E4 – here
- Polar H10 – here (valid ECG as of Dec 2022)
- Garmin Fenix 6 has an oHR that is NOT ECG-capable (the wording on the chart implies to the contrary)
Parody: Garmin Fenix, Forerunner and Edge Messages – What they really mean
Last Updated on 2 October 2026 by the5krunner
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This test was done while exercising, night measurements should be more reliable.
“…completed a submaximal exercise test while wearing a reference ECG (Biopac) and a randomly assigned chest-based monitor (OMNI, Polar H10, Equivital EQ-02, Zephyr Bioharness 3).”
good spot, ty
It makes no sense using very old Fenix 6 with its outdated sensors.
for a scientific project I agree. however these things can take quite a while between the planning, execution, reporting and publication stages.
so it might have been current at the start of the process
would gen 5 sensors be THAT much better. I suepct not. but then again my suspicion isn’t science.
The sensors haven’t changed much, especially compared to a chest strap. Even if you shave and keep the strap super tight theres still a lot of light & movement interfering
As a scientist, not impressed. This study is pure bs