I've a Forerunner 255 since November and at the moment I've SW 13.23.
I've utilized the watch when running , and compared HR data with a HRM-dual collected by a 920XT. Data are quite similar, just 1 bpm difference on average.
Then I compared to a Venu (1st generation) which I don't use it anymore because of a majour defect of display (became green instead of white). During a running activity BPM data of 255 are practically the same as the Venu. Therefore I was reasonably satisfied until I discovered that during a normal walking (with or without an acitivity) after 5 minutes walking data becomes totally crazy. Meaning something between 100 and 160 bpm during normal walking. First time that happened I became almost afraid to have a cardiac desease, but then I have put the Venu on the other wrist at the same time discovering that my heartrate was absolutely normal when walking between 60-70 bpm.
I performed the following test:
- Excluded Move IQ - failed (meaning that the BPM rate was wrong compared to the one I've on Venu on the other wrist)
- Tighten the watch on the wrist- failed
- Rotated the watch and positioned under the wrist - failed
- Put some water between watch and wrist, to obtain humid skin - failed
- Activate a walking activity - failed
- Inverted wrist, positioning Venu on the left wrist and 255 on the right wrist. failed. Venu is always ok.
- Utilized a HRM dual instead of Venu sensor on the other wrist. failed (sensor on the chest was ok)
Then I don't know what to do anymore. It's a fact that when walking 255 is giving totally wrong heartrate data, despite the fact (or due to the fact) that is utlizing a new sensor or the algo for walking is not reliable. To notice that inhouse (or outside) if I don't move the HR seems ok . But then if I start to walk, not immediately, but after 5 minutes the rate shown increase like crazy. At the moment temperature outside are beween 4-8 degrees Centigrade. I can't say if it will happen also at higher temperature
I've followed what it is said in the manual with no results:
Tips for Erratic Heart Rate Data
If the heart rate data is erratic or does not appear, you can try these tips.
• Clean and dry your arm before putting on the watch.
• Avoid wearing sunscreen, lotion, and insect repellent under the watch.
• Avoid scratching the heart rate sensor on the back of the watch.
• Wear the watch above your wrist bone. The watch should be snug but comfortable.
• Wait until the icon is solid before starting your activity.
• Warm up for 5 to 10 minutes and get a heart rate reading before starting your activity.
NOTE: In cold environments, warm up indoors.
• Rinse the watch with fresh water after each workout.
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At home during the day, and in the night , bpm are ok . also resting HR measured is ok (exactly the same as Venu) -
Whern running an activity data are ok (except during warm-up but this is normal (also mentioned on the manual and also happened with Venu on the wrist ,not with the HRM)
What I noticed is that compared to Venue HR on 255 , (both in no move arm position) is going up and down of 1-2 or even 3 bpm quite frequently in respect of Venu that looks much more stable, that let me think that is an algo issue.
May Garmin fix this annoying problem ? can't be acceptable to have such an issue . Those wrong bpm rate when walking are generating extra and wrong weekly Intensity minutes even without an activity.
If anyone has the same experinece or has some suggestion is really welcome.
Thank you