I switched from a Galaxy Watch to something more performance-oriented and chose the Garmin Forerunner 255 Music.
I’ve been using it for about 2–3 months now, and I’ve noticed that during high-intensity workouts, the heart rate sensor doesn’t work properly at all. It stays around 150 bpm, even though I know I’m closer to 170–180 bpm.
This is extremely frustrating, because I bought a Garmin precisely for better accuracy — and now all my training data and metrics are skewed.
I’m attaching two examples: a Cooper test (12 minutes at very high intensity) and an interval session (10×1 minute). You can clearly see the difference in effort, but the heart rate hardly changes.
Has anyone else experienced this issue? Is there anything I can do to fix it?
Should I consider replacing the watch?