I like your post, Leo, because it is helpful and has good advice. I am sixty-seven years old in fairly good shape and a few months ago my twelve year old grand daughter asked me if I'd take a tkd class with her - she was starting her second session. So I did.
I'm fairly active - I either cycle or hike every day - and do some exercises - so I was in fairly good shape for a guy my age starting out.
I've never done any martial arts in the past other than for the past few years I've studied bagua aikido from books and online videos, etc.
I'm discovering the challenges of waking up the hips and joints, stretching out, and learning the precision of the forms. I spend an hour or so every day stretching and practicing the forms and I like it.
I'm new to this forum and this is the first time I've posted anything here. I'm the kind of person who starts something and when I like it it becomes a part of my life even part time for the rest of my life.