| I know this problem and I found out, that whenever my pulse is arrhythmic it says 00. Usually my pulse dances in 3/4 waltz, except when I climb mountains. When I put my X3_HR on at home, it says 00, after a while it shows the pulse. I had been to the doctor and he counted more extra systoles than normal systoles. But only when I am lazy with a pulse of 40 - 60. |