Fenix 5 - very Poor Heart Tracking with Tennis

I have had my Fenix 5 now for 3 weeks. With Running and Cycling Optical heart rate tracking works fine and gives me ball park figures (i train with a separate heart rate strap so can control the numbers). However in with tennis the values are just, to put it bluntly POOR. i know from experience that the HR should be between 130-170bpm in hectic games. I am not a OHR noob, have had a Polar A360 just for tennis for a while but made the switch to Garmin. The A360 2 years old worked better than the Fenix 5.

I have set up a training called tennis on the watch with only OHR on (no GPS)

I did the normal things to control the OHR. (wait for a lock, correct wrist fit, even shaved some hair of my wrist, put a sweat band over the watch to occlude ambient light, checked fit), but alas. My Fenix tells me my heart rate is 70-85bpm for most of a match... I know a chest strap is always better than OHR but this is just poor! especially in a €600 watch. See screen below

Anyone have an idea if the accelerometer / OHR maybe have a bug? Or the algorithms at Garmin are not up to interval training?

I hope Garmin reads these threads and can reply on this.

Top Replies

Ma73ko over 7 years ago +1

Really I can not accept that Garmin is focused to introduce new Yoga profile and not a Tennis profile. Coming from a Polar M600 I trust that OHR can be in the ball park even during tennis activities.
I…

All Replies

0 mcalista over 8 years ago

Just a thought, but if the watch is on the same arm as your racquet, then the impact of the stroke may be causing movement of your watch, and letting light into the OHR reader.

0 Cobuswww over 8 years ago

Good point.. I should have mentioned that the unit is not on my playing arm and i have single hand backhand. So no judders because of the racket. ;)

0 Former Member over 8 years ago

OHR sensors will not work well with those types of activities. You should probably wear a chest strap monitor for tennis.

0 mcalista over 8 years ago

OHR (regardless of brand) tends to be slower to track changes in HR than chest straps which pick up on electrical signals, and probably not as good for HR based interval training. Of course, you can still use a HR strap with the Fenix 5 (and in fact you can now use a BLE strap as well as ANT+)

0 Cobuswww over 8 years ago

I appreciate that advice... 2 points on that though. The bog standard Polar worked well (OHR) so it can work if the algorithms are ok in tennis activities, 2) and using my Bluetooth chest strap is a no go as the BT pairing seems to be problematic with the F5 / Forerunner 935 (refers to numerous other threads)

My expectation for this kind of unit to be " slightly in the ball park" is not unreasonable is it? I don't need or want 100% accuracy with the OHR, but it is so far off now that i'm thinking what the hell is the unit smoking?

Currently my "upgrade" to F5 feels like a very definite downgrade

0 Ma73ko over 7 years ago

Really I can not accept that Garmin is focused to introduce new Yoga profile and not a Tennis profile. Coming from a Polar M600 I trust that OHR can be in the ball park even during tennis activities.
I wrote to Garmin support but no answer yet.

Is in the forum any place where user can ask further development? In the beta sw tread?

0 JSRUNNER_ over 7 years ago

It's probably not the algorithm as across a wide range of OHR devices and manufacturers people report a poor performance in racquet sports. Also they sometimes see different performance between two devices from the same manufacturer using the same OHR hardware and algorithm - the differences being (probably) due to the physical fit between two slightly different shaped devices with different bands.

I know its not what you want to hear but why not just wear a chest strap?

0 Ma73ko over 7 years ago

Less comfort? For a sport where you move your arm a lot?
Look around in the forum and not only racquet sports have bad OHR performance (more than 50% of miss measurement) but also Strength workout...
I need ball park not 100% accuracy.
And I can't understand why if I run to cross a street my heart rate to 120bps is recorded (correct or not) while if I run to the net in the tennis court is impossible to go higher than 100bps?
Something in the algorithm is fuzzing the watch, or the sampling rate is way lower than what is declared.

0 JSRUNNER_ over 7 years ago

Simple equation - accuracy then chest strap or OHR further up arm. Not sure what use ball park is to you anyway.

Don't think its the algorithm as its a common problem to other OHRs not just Garmin

Wasn't saying it's only racquet sports - it's cycling and running too for many runners as well as the strength training you mention

OHR is mainly useful for 24/7 monitoring

Not sure what you mean by less comfort when you move your arm a lot - it's on your chest and doesn't give me problems for squash, swimming, running

0 Ma73ko over 7 years ago

I really appreciate your opinion but I'm not complaining about accuracy but about really bad and wrong HR data, even compared with other OHR (Garmin or not).
Further more HR data are more reliable if I do not start activities when I play tennis....with out changing hardware.
I think that something in the algorithm is wrong and Garmin MUST fix, and this is my humble opinion.
I had to add that, after several days, I have received non answer from garmin support (Disappointing for a top end product)