Also you don't have to be a great athlete to ride a bicycle long distances. I know that my dad was still doing century rides in his late 70's despite the fact that he was never a competitive athlete at any point in his life.

Me, I am almost 62 and have been trail running over 40 miles per week lately. I am not fast and don't consider myself an athlete, but I can run 15 miles before breakfast if I choose to and definitely plan to do more long bike tours and backpacking trips.