I just a bit tired of docs saying everything is OK when they can't actually give you a reason for the symptoms. My doctors exact words, "Yes, that is strange that your HR stays that high for so long, normally athletes heart rates return to normal pretty quickly." Great!! Thanks Doc!!
I would suggest seeing a Cardio or an EP. I had this problem and it ended up being a combination of Sick Sinus Sydrome and A-Fib. Now am on medication and have no more problems. Or it just be nothing,HRs are strange things and vary from person to person,also this was diagnosed when I was 62, 10 years ago,although I have probabley had it all my life. I was a high performance biker in my youth,but we knew nothing about this stuff in those days. No pulse monitors those days, and as for A-Fib, just rode through it.
Regards Ian
Yes, that's 4-6 hours for normal resting HR to return.
Interesting, and given a doctor has no idea, how can I even guess? Well here goes anyway.
You have a very low rest HR, in my experience, thus I'd guess your heart would accelerate (HR) quickly when you start exercise, it was "running" in a just enough mode. Next, a HR of 90+ for some period of time doesn't strike me as unusual either, especially if you are still on you feet, not resting.
Now a question, you said: "4-6 AFTER exercising" what is the dimension? If minutes, sounds fine to me, if hours, that seems too long to me for a HR returning to the rest rate, again if you are really resting.