Missing Beats or Short Final Reading Duration
If you think that your heart rate monitor is missing beats or if the total reading duration appears to be less than you expected on the results screen, here are a few tips you can do to troubleshoot:
Chest Strap: Chest Strap Tips For Better Accuracy
CorSense: Hand, Wrist, and Body Positions When Using CorSense
The tips in these articles may resolve the situation for you.