Some more reports on social media on the reliability of the new Garmin 225’s heart rate.
Generally, it seems good and accurate to most people. However, one chart, below, shows the perennial problem with chest straps of dropouts seems to be periodically occurring with some users.
Martijn shows the following on a tempo run (at 01:06:40):
I’m somewhat surprised as the MIO sensor (which the 225 contains) has always been very reliable for me over the numerous MIO devices I have.
anyone with other experiences?
Last Updated on 14 January 2026 by the5krunner
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I got so frustrated with the optical HR monitor on my 225 last night that I’m on the web right now searching for what to do about it. Most of the time it’s good, but sometimes I’ll be pushing up a hill like last night, my heart pounding, and I check, only to find it’s reading 87 “no zone”. What the heck?? The strap was so tight it was twanging the nerve in my wrist, so I loosened it a bit, but still below 90. Ten minutes later I looked and it was at 135, so at some point it fixed itself, but not before a lot of ineffective fiddling and cursing.
Maybe not so tight. Maybe spin round wrist. If bend wrist u will affect blood flow
Thank you for the suggestions. The only one I didn’t try is flipping it around to the watch face is against the inside of my wrist rather than the outside; I’ll try that.