Usually, but not always in the first 5 minutes of a run, my heart rate monitor gives me readings of 240. It stays there for around 20 seconds and than it could drop to 190 or 220 than drop down to 119 or 139. After about 5 minutes is usually stabilizes around 145. Sometimes the rate jumps to 190 during in the middle of a run. I know that this number is not accurate. This is driving my nuts and it's very distracting during a run. However, I need my HRM to keep me running slower.
I have been wearing a heart rate monitor for over 10 years. The current one I use is a timex. The best heart rate monitor I ever owned was the acumen and the worst was the polar. All the HRMs I have ever owned have given me strange readings. However, the most accurate was the acumen.
Why is this happening? My husband tested my HRM and said that he didn't have a problem and it's very accurate. I use a polar heart rate bra that holds the monitor in place. Could this be causing my bad readings? Also, I have considered that I have heart arrhythmia. I did go to the doctor last year and got an echo stress cardiogram which I didn't get any call backs for. I do have very low blood pressure and have a low sodium diet. Does this have any relevance?
Finally !! I figured it out !
The problem is the Polar Heart Bra.
The Bra doesn't hold the monitor in place properly. The heart rate monitor needs to sit high and flat against the rib cage. I got rid of the bra, strapped on the monitor really tight and my problem is solved. Yippee!!