Heart Rate variance

I've got a Mk2i and also the gamin dual heart rate strap. The variance is days apart. I'm getting 135 on the strap and 100 on the watch. This is only a recent thing. I feel there might be a problem with the watch.

Should I send in for warranty? Sometimes its out by 1-3BPM but this is really bad

0 trux over 4 years ago

Have a look at the document for some insight on the accuracy of Optical HRMs: [The Heart Rate Sensor on My Garmin Watch Is Not Accurate]

0 Peter.Bomberg over 4 years ago

I have for the fun of it used my garmin while riding on my bike trainer and compared to the trainer road numbers and honestly it's impressively close!

I was expecting 10+ fluctuation all the time but it's within 1-2bpm consistently as long as the watch is tightly on my arm, once it starts sliding around it's hit or miss.