Ghost Heart Rate


macrumors regular
Original poster
Nov 20, 2009
I just updated my series 4 os to 5.1.3 and noticed my rate was on the low side for most of the day. I’m on some meds so was keeping tabs on it more than usual. Last night I went to bed and put the watch on the charger at 11:11 and woke up at 5. I noticed my watch had come off the charger and was low in battery so I put it back on until 6am.

In checking my heart rate history today, it appears from 11:53pm until 3:47am, my rate was recorded 33 times. I topped out at 165, which was a neat trick in a sound sleep without wearing the watch.

What could trigger a false reading like that? I promise no ambien was involved.



Sep 24, 2014
Mine is not that bad. But, when I put the watch on in the morning it will sometimes show a rate of 110 for a time before I put watch on. I use Cardiogram which is on my watch face.

What app are you using?

Not sure if low battery would cause your issue.

Try rebooting watch and iPhone and see if it stops the false readings.


macrumors 6502
Jun 29, 2015
I saw this once a couple of days ago. Heavily elevated heart rate between 12 and 03 AM while not wearing the watch (and beeing asleep). No third party app. Don't remember whether it was on the charger or not.

Dracula? :D