I have been using the Blaze for about 4 months now and still can’t get it to accurately measure my heart rate during exercise, and the measurements it does take are very erratic. I read many posts on the subject and tried several different resting positions on my arm but I still can’t get it to track accurately. I tried placing it higher on the arm but the reading is in most cases still lower then my actual heart rate by 20-40 bpm. Sometimes even by 50 bpm. It also will not stay higher on the arm for long as it slips back down due to sweat and the fact that I’m running. I noticed that if I stop exercising for a short while, the heart rate will start climbing to where it should be, but then drop back down as I start exercising again (very strange).
I doubt it has anything to do with it but I do have, and always had, a higher than normal average heart rate even when I was in top shape. My resting heart rate is 80-85 bpm and even when sleeping I really go below 75 bpm.
As an example, here is my heart rate for yesterday:
Most of the day I was working on my computer with very moderate physical activity, but I had a treadmill exercise around 10 PM. Obviously, I need to change the Zones settings but it will not change the fact that the heart rate readings are erratic and inaccurate.
Any ideas other than changing the position of the Blaze on my hand ?
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Welcome to the Forums @Oferbendov and thanks for the attachment. If your hear information is not being accurate, I recommend checking this post where you will be able to see some things that might be causing the discrepancies and some tips on how to make this feature more accurate.
See you around. 
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