I have about 10 days tried my Vivofit to move the chest strap to meaningful work. It did not succeed. Employed (every few minutes) broke off the signal and heart rate values were meaningless - to shut during the running training on 28 bmp, average 44 bpm. With these values one normally lies on the operating table and receives a pacemaker. My normal values (sphygmomanometer wrist) are at rest 56-72 bmp. I have tried different positions of the sensor (clamped under Sports Bra, fixed on his back, with tape), I have ultrasound gel used to improve the skin contact. I have read the instructions and FAQ page on the Garmin Web site and tried the instructions. The results were disappointing and not reproducible. Today I have decided to return the chest strap.
