Fenix 5 report too low heart rate at any intervall training.

Hi,

is there anything that can be done to this issue? At this point wrist HR is unusable to me. It does not give any sensible readings if i do any other than basic running exercise. Few weeks ago I forgot my chest strap at home from my ice hockey practice. Week after that i got chest strap with me at practice again. I knew that wrist HR would not be as accurate as chest strap but the difference is so huge that there is no reason to even use wrist hr at my training.

Point is that even thought wrist hr has it limits there is no excuse to be this wrong:

Wrist Hr
AVG HR 128bpm Max hr 177 Training effect because of these 2.8 and calories 680C

Chest strap
AVG HR 154 bpm Max hr 195 Training effect 4.6 and Calories 880C

Both practices were identical and my fitness levels were about the same (these would make only few bpm difference anyway). I'm not fittest person in the world but I know my data and that chest strap reported HR is almost spot on what it should be. I have noticed this same behavior when i do interval running. Basically you can't do any interval running with hr rates with the watch.

Something else i noticed is that after a shift i took watch of my wrist and it did not drop heart rate even if it was off from my wrist over 5seconds.

I know where i should were the watch to get any sensible data out of it so that is not the problem here.

When the watch also has GPS issues and Altitude meters report floors climbed when i stay still and sit at my chair there is something seriously wrong here. It is 500e watch here at Finland so I do have really hard time to believe that these are "features" and not flaws.

0 HanSolo over 5 years ago

[h=3]Wrist-based Heart Rate[/h] On your wrist, Elevate wrist heart rate technology lets you monitor your heart rate without wearing a chest strap. In addition to counting steps and monitoring sleep, the watch uses heart rate to provide calories burned information and quantify the intensity of your fitness activities. It also measures your heart rate variability to calculate a stress score that helps you assess what level of activity your body is ready for.

This is from Garmins web page for Fenix 5 Pluss

And for Fenix 5

[h=3]Multisport GPS Watch for Fitness, Adventure and Style[/h]
Premium multisport GPS watch with Elevate wrist heart rate technology¹

And reference to a non working link.

¹See Garmin.com/ataccuracy

WhenI first bought my Fenix 5, I did not know anything about workout. Maybe my bad.
But I read the review, and the advertising from Garmin.

And I realised soon, doing my fist HIIT, that the OHR was totally wrong.

I have since that been reading my self up, and are wearing my wrist band at all my work out. I have also read the manual where Garmin says OHR are not accurate for weigh training of hit, intervals, etc.

All this is fine. But Garmin should be open about this in their advertising. OHR is a great tool for mesuning for over day to day HR, resting HR.

But don't expect all buyers are experts from day one.

0 simonsev over 5 years ago

@simonserv I think DCRAINMAKER talks a bit about the different sensors used but there is a limited selection. Agreed software is a huge factor but also the positioning and the weight of the unit have quite a big impact. I find the OHR on my 5+ to be poor where I have used it for activities - which has only been for slow walks as I use a chest strap when training. Whilst the innaccuracy is an irritation I only really use the OHR for the 24/7 monitoring and don't try and use it to measure or guide training sessions. I'm sure the software will improve but the optical method is always at a disadvantage when it comes to HR measurement being remote from the heart and needing to work around so many different variables from one user to another across a huge range of very different activities.

As for age - are you suggesting its the younger or older users that are more impatient :)

Yes you are correct on the DCRAINMAKER discussions, excellent reviews and I follow all of his testing and musings with much interest.

Also totally agree that the optical method needs much more tweaking and likely AI type tech to really become accurate considering all the variables. I am also going to try a chest strap but as I have indicated I think the F5 is working well for me, the inaccuracy I am seeing is recent and followed the more recent update. I also am not worried about absolute accuracy but I would like precision, which the F5 did have (and I am sure will come back) getting my heart rate up above 140 or so on either device with consistent workout regimes, F5/FC3, is a solid workout for me and I like to track that and be pushed to achieve that. (which I cannot do if it is reading 70 when it should be around 140 based on the FC3 and good old fashioned fingers on the throat check)

As a young-at-heart 51 I don't see myself as either young or old but it is absolutely the under 25's who have the impatience issue from my experience! ( I hope the tongue-in-cheek is coming across here, all meant in good humor!)

Just to add another interesting observation I seem to be seeing, it is only the morning stints it is proving really dodgy and the temperature reading on the graphs drops in sync with the dropped heartbeat, while steps and etc from the accelerometers are consistent always. (no idea why temp would drop and workouts are mostly inside at normal room temp on the treadmill)

0 JSRUNNER_ over 5 years ago

@Simonserv interesting - how low does the temperature drop ? Just wondering if both errors relate to the watch somehow not making full contact with your skin - don't know where the temp sensor is?

0 simonsev over 5 years ago

@Simonserv interesting - how low does the temperature drop ? Just wondering if both errors relate to the watch somehow not making full contact with your skin - don't know where the temp sensor is?

Temperature drop just shows as a sharp drop to 24 degrees low so yes, almost like it is not properly attached except HR is showing as resting levels, 55 or so, cadence shows a level 125 or so the whole graph so accelerometers are working fine. Temperature it is just atmospheric temperature, through the sensor opening below the start button (I think?) designed to work when the watch is not in contact with your skin (attached to your jacket hiking for example?) is what I understand, same way the Casio's work and the graphs show the same sharp drop (HR+temp) at around the same time. Watch is tightly on my wrist as per usual with the Garmin metal strap adjusted correctly.

It has not shown the inaccurate readings again (2 days workout so 4 x treadmill sessions) since I started using the hack of session recording when my heart rate is up to exercise level, 120+, it is fully updated to 12.40 now via Garmin Express.

0 JSRUNNER_ over 5 years ago

@Simonserv I never get accurate ambient temperature readings from the watch as it does seem to be influenced by proximity to the body. I wear a tempe generally when running which seems reasonably accurate

0 simonsev over 5 years ago

It is back to doing exactly the same thing again, stubbornly refusing to go above about 95, I will now do what I promised myself earlier and stop obsessing over it and let it work itself out. Annoying of course but time to shrug and just use it as a field watch again. What was totally ironic is that I pushed hard the pace to see if it would wake up and I got my fastest mile/fastest km recorded at sub 100 heart rate, Garmin must think I am very fit!