Fenix 5S HR monitoring is grossly inaccurate?

I got my watch about a week ago, installed all the proper updates, and have been using it daily. I have noticed an issue with the HR monitoring across the board. I primarily do CrossFit, which means my activities vary from lifting to running to random cardio movements to strength. I can push myself to the brink and be lying on the floor breathless and the watch is reading my HR as something like 110 or even as low as something like 84. The only time I seem to get any semblance of accurate HR is if I am actually running or jogging, with my arms pumping. When I check, I will then be in the cardio zone with something like 140-150. Other than that, my watch does not seem to pick up changes in HR accurately. I have tried the strength setting, cardio setting, etc and was starting to think maybe I needed to update my software, but it is up-to-date. I have also tried re-positioning the watch on my wrist, as well as both tightening it and loosening it. Nothing I have done has seemed to improve the HR monitoring.

Note: I previously had the Forerunner 225 with HR monitor, so I am familiar with the wrist HR monitoring. I would have issues from time to time with that watch's HR monitoring, but not like this. I recognize that wrist HR monitoring is less accurate than a chest monitor, but I have upgraded my watch (at a hefty $$$) for what appears to be less accuracy.

Can anyone help? Is anyone else experiencing this?

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0 Pierrotsc over 7 years ago

If you want the best wrist HR monitoring, get the Philips Health watch. It is not a fitness watch though so you will not get all the extra that Garmin provides but you will get accurate reading doing HIIT, crossfit..

0 Richard2145 over 7 years ago

The Philips Health Watch is very expensive and limited features. I would rather use the Garmin Chest strap at less than half the price and gives more details about the run like Cadence, stride length etc

0 miroman4o over 7 years ago

Hello, I can not agree with philipshambrook that "It's not a bug. It's a limitation of WHR."

I have exactly the same issues as l0nepinemall and Richard2145 described.

I had a forerunner 735xt and it gave me correct heart rate readings during strength workout, no I have fenix 5 and it gives me correct heart rate during running, but about 80-100 during heavy strength training and I can not even get into heart rate zones. I have to say that I have veins like Hulk and I can even see them moving and count heart rate at about 160 with my hand.

When I count my heart rate during strength training with my hand it is not as clear as it is when resting, maybe the watch catches 2 beats for one I don't know but it can have some kind of sensitivity calibration with chest strap so it can measure better.

0 cmbauer over 7 years ago

I have yet to compare mine to a heart strap. Tightening mine up and placing above my wrist bone seems to operate well. attached are just 2 different sessions. The one with the drop in HR was me taking it easy on the row

This is similar to what I get. I move mine up the wrist and tighten it down and its pretty decent. I sometimes where my Schosche Rythm when I have to wear my wrist straps. I am totally satisified with the WHR of my 5

0 1-Ghost over 7 years ago

I lift daily, and whr doesn’t work. The wrist movements and muscle flexing throws it off. I use chest strap exclusively for lifting. Same issue with vAHR and F5. It’s not the watch, it’s a optical hr limitation when wrist mounted.

0 SteveCRunner over 7 years ago

If you want to record a chest strap and wrist HR simultaneously in the same activity, look into the data field from Connect IQ called "Auxiliary Heart Rate". You can then look back at the activity and overlay one line on a graph of the other HR graph. You can spot where the two correlate of deviate, and relate it to what you were doing. In a process of trial and error you can then see what activities are OK with WHR, etc.

0 ih8rain2 over 7 years ago

I experience the same problem. The optical HR monitor is disfunctional during my weight training and I am heavily disappointed. Especially for the fact that it is an very expensive watch. I was using a Polar A360 with optical HR. Works fine but I hate the strap. So I thought I treat myself with something nice which eventually proofs a big disaster.

0 ih8rain2 over 7 years ago

Did anyone complain with Garmin?

0 Ma73ko over 7 years ago

Did anyone complain with Garmin?

I wrote to the support because I have the same problem during tennis session... Previously with a polar M600 OHR All records where perfect..

0 chong67 over 7 years ago

I am happy with the result on the WHR when I go walking or jogging on my F5. When I go cycling, I use the chest HRM.