I don't run like PTGump but I enjoy hitting the pavement from time to time regardless of what my dadbod suggests. Usually around my block little over 3 miles. But I'm starting to get concerned about my knees, especially the one that has the replaced ACL in it. I know, I know, "drop 20 and it probably won't be a problem", not sure it's that simple, though. I think 39 years many of which I've spent playing sports, running, basketball consistently up until around 35 have taken it's toll. I can feel it even after a round of golf.
Going to have to start doing some lower impact stuff, might even venture into yoga and hit the pool for some laps. Running isn't the most efficient way to exercise anyway, but I did find it to be a good stress reliever.