Spoke too soon on my statement above. I paste here a message in another thread as it applies to both of my responses last night.
"Well be careful of what you say, I could be advised.
After talking with pride about my low (lower) heart rates following a recent cardioversion I noticed this morning while still lying in bed I could hear my heat beat against the ear on the pillow. I counted without the benefit of a watch, but still the rate sounded to be too high. So when I got up I put on my chest strap exercise monitor, and the HR was in the high 90s. Sitting here typing, at rest, the HR is 100. Something seems to have gone wrong here, but I'll set back and watch before looking for help. The heart sounds to still be in sinus rhythm."
I think I will take an "extra" dose of Toprol to see if that brings the HR back down. My hope of getting off of Toprol may have just been dashed. Not self pity here, just disappointment, I am happy the heart sounds (absent an EKG) to still be in Sinus. I note too that the HR doesn't go up much when I get up an walk around, for some reason it just doesn't "want" to return to the lower rest rate. Hope it isn't something that can't wait my next follow up with my cardiologist early next month.
You didn't say what your age is and physical condition, and I think that has something to do, in general, with what you HR "should" be when walking at 2.5 mph, I assume. I'm a senior citizen and think that at 2.5 mph my HR would be almost at "rest", in the mid 60s to low 70s.
I also have suffered from Atrial Fibrillation and a leaky Mitral valve. The Mitral valve was repaired last November, but I continued with AFig until early this month when I underwent an electrocardioversion, and my heart is now in sinus rhythm. I take Toprol and Rythmol to help keep it that way. The Toprol/Metoprolol does tend to keep the heart rate lower than it would be without.
My reading is your HR is high at rest, and normal at a slow walk, i.e., your heart is pushing more blood around at rest than is needed, but I don't know what that means or that it is even a problem. It seems beating makes the heart go stronger, that's what exercise is about, muscles get stronger when used harder.