Welcome to Connect @concretesue. You will see that I moved your discussion to this related conversation "Smart watch to monitor heart" where members are discussing what type of personal monitors they should use to track their heart. I'd like to share the following website and video https://wiki.ezvid.com/best-heart-rate-monitors
The video in the upper right of the website rates the top 10 heart rate monitors and it looks as though the Apple watch comes in at number 2, only secondary to the Garmin Forerunner 945.