Navrig wrote: 11 Mar 2024, 3:18pm
I wouldn't lose too much sleep over what your Garmin watch is telling you. The accuracy of the HRM function is pretty poor in my experience.
I had an earlier fitness model, Vivoactive 3, which I tried to use for fitness stats but when on my turbo trainer it was telling me my HR was 90-100 when I was knocking my pan in. I knew it was north of 150. I reverted to my Wahoo chest strap and, sure enough, it was reading 150+ for a 90-100 watch reading. The watch then just became a watch - it told the time but the battery life was so poor I couldn't use it for cycle route recording. I could, and did, use it to record 10km runs.
I gave up using it until I started to read reports that new technology meant watch HRM were more accurate. I wanted a watch I could use for my golf and fitness so I opted for a Fenix7. Battery life is much better, great for golf but the HRM is not much better. The chest strap comparison still shows a significant, but not as much, discrepancy. 90-100 on the watch equating to about 130 on the chest strap. The watch improves if I tighten the strap but I have to release it when my fingers start to turn blue.
Watch HRM are still Emporer's clothes territory but Garmin don't wan't you to know that.
I found a Polar H9 (chest sensor) around £30 so thought I'd see what that did compared to the Garmin watch and ... big difference.
Major difference is that the Garmin after 10-15 miles would start giving unexpectedly low readings eg 60 bpm, so I'd really push it, be breathing hard, legs really feeling the extra effort, etc. and Garmin HR stayed at 60-70. Had me wondering if it's my lack of knowledge as the flow is not only a function of heart rate. But the HR shown by the Polar makes sense, no unexpectedly low rates, push hard and HR increases, coast and HR drops to something that makes sense to my non-medical understanding.
1. Garmin plot on Garmin Connect include one for Stamina. Unsure how they calculate it. Plot sort of made sense in that at start of ride it's high and through ride it declines. But for no apparent reason there were "glitches". eg
But using Polar H9 no such glitches, just a smooth straight decline.
2. Garmin watch was used with "broadcast HR" feeding into my Edge cycle computer so just using it as a HR sensor (ANT+ HR sensor). Polar H9 is also "feeding" straight into the same Edge also just as a HR sensor. But using the Polar Garmin Connect now seems to also be recording a respiration rate. No idea why.
3. No dropouts -watch would just give-up recording occasionally, several times per ride. Wasn't a communications issue as check the watch and it showed a HT of "--"
Watch has gone back to Garmin for refund, not because of the HR sensor shortcomings but daft automated activity sensing that you can't disable. The watch kept deciding I was having a nap. Generally once or twice a day, sometimes 3 times it would be recording a 20-40 minute nap. I don't take naps during the day. No way to delete these phantom naps. Loads of frustrated users having the same problems across many Garmin watch models. Apparently it's been an issue for ages. Simple option to add a setting "Nap Detection: Enable/Disable" - Garmin wont do that (and that would solve it for many users). Whats worse is you can't then delete these phantom naps. Their system is so convinced you've has a snooze it wont let you delete them!
Many watches tell the time so spending a lot lot more on a Garmin thing to get the activity functionality and for the cost you don't expect so many shortcomings. Hence return for refund.
Ian