My heart rate fluctuates depending on excercises. It’s usually the lowest when I wake up. Not sure what it is at sleep, perhaps a little bit lower.
This was just a short time ago while eating lunch.
Waking up heart rate.
When I don’t excercise, esp. cardio, heart rate is in the mid to upper 60’s. Heart is a muscle, it becomes more efficient with exercise. Unless you have some type of heart condition/defect, I would not worry about it.