Three times this week, my Charge 6 displayed surges up to 173 bpm while I was sleeping. My band is not too tight or too loose. As a result I had an EKG done, which disclosed no issues. My blood pressure was measured: 116 / 63. And when I exercised yesterday 1.2 miles, my Fitbit heart rate maxed at only 102 bpm !
Moderator Edit: Clarified subject
