HRM goes to zero


New Member
Dec 24, 2010

I am banging my head against a wall here trying to figure out just what is going on.....THE PROBLEM - When my excertion gets upwards of 175 my HRM goes to zero and will not regain my heart rate until I totally remove the chest strap and re-start the monitor. If I try to just remove then replace the chest strap I either still get zero or a crazy hodge podge of values. I have tried the following to solve this problem:

1. Checked the problem in numerous and varied locations to ensure it was not interference from power lines, transformers, etc.
2. Removed ALL other electronic equipment - watch, cell phone, I pod.
3. Purchased and used three different HRM (Polar S150, Blackburn Delphi 5.0, Garmin Edge 705) and ALL of them perform in the same fashion.
4. Have visited my family doctor who advised me that my problem with the HRMs IS NOT CARDIAC and to look at other causes. EKG and stress tests completed.
5. I have ensured that the chest strap pick-ups are moist enough.
6. I have used that special HRM gel they sell
7. I have used homemade sweat bands around my chest thinking there may be too much moisture.
8. I have purchased and installed fresh batteries in both the strap and head piece.
9. I have talked to manufacturer representatives and they have no idea what I am talking about.
10. I have increased the heart rate zones on the monitors to insure there is no "fail safe" intended to slow you down if you are working above your maximum HR.

This happens inside and outside (just this morning in a spinning class my Polar went to zero after 30 minutes) but seems to happen less when it is colder, below 45 degrees F. This is what made me think it may be excessive moisture.

ANY help or suggestions are appreciated.

Have you made sure the strap is tight enough. My guess is that as you reach your max HR, you may be moving too much and it becomes loose. Just a guess.

I believe it is tight enough.....At one point I REALLY cinched it down, to the point it was quite uncomfortable, but still had the problem. I have since relaxed it a bit but it remains quite snug.