Hello, I ran for the first time in a while today. I have recently been very out of shape and have not exercised enough in the past couple of months. Today I lifted with my friend for under an hour, drove 30 min home, and ran 2 miles with my dog. After I ran, I saw my max heartbeat was 160, which I believe is normal, but it has remained extremely high for hours, ranging from 110 to around 85. Around 20 min ago it went back to normal. (This is all based on my fitbit).