I'm 63. I make a point of walking 5Km (3 miles), every morning. I'm usually out the door, by 0530, and back in about 50 minutes.
I was running, but kept getting injured, so it switched to walking, several years ago.
I think keeping my mind occupied is just as important. It's entirely possible that the visual stimulus of her walks was as important as the exercise.
For myself, I make a point of constantly working on shipping software, and constantly learning new stuff. LLMs have been a godsend, for the latter. I had pretty much given up on trying to ask questions, because of the awful, sneering responses that I was getting, more and more.