High intensity heart reading on Series 4


macrumors regular
Original poster
May 3, 2009

I see that the series 4 has a different heart rate monitor.

Could anyone with a series 4 let me know what the heart rate readings are like for high intensity exercises? I do a lot of HIIT and CrossFit and I was wondering whether the watch could handle these activities.



macrumors newbie
Dec 7, 2014
Just got the new series 4 Apple Watch and was initially very impressed with the heart rate. My series 3 would do quite well with an outdoor run and walk but would not do well while playing hockey or swimming. New Series 4 seems to be bang on for hockey and swimming. However, when I went for an outdoor run it was way off! It would not change and stayed at the same reading of 126 for nine minutes, and I know I was a lot harder than that. After that it went to 146 for five minutes and I know I was not that high . Has anyone else experienced this?
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.