Issues with my heart rate data when I do HIIT and crossfit exercises

3887992 1 day ago

I use an HRM pro with my garmin forerunner 945 watch when I do my HIIT exercises. When I do not use the Hrm, the watch shows my heart rate significantly lower than when I use it. An example is that for the same exercise I have an average heart rate of 165 with the maximum heart ate being 188 when HRM is used and 140 heart rate with a maximum 155 when HRM is not used. As you know HIIT and crossfit are high heart rate exercises so 140 is definitely not an accurate measurement. I know that the HRM is a more accurate device for the heart rate but it is unacceptable for a watch that is that expensive to be that inaccurate.

Any advice on that?

Thanks,

Greg

0 e7andy 22 hours ago

Use the HRM is the solution that will give you the most accurate HR measured. Optical HR will very easily be incorrect so don't trust it.

The optical HR for lower HR values seem to be a lot more accurate.

If you still want to use optical HR during exercise then try tightening the band 1-2 holes so it sits a little tighter. Make sure it it placed correctly on the arm. About two fingers from the hand above the wrist bone.