Then the dog died. Instead of walking 10km per day, she lay on the couch staring at the ceiling. About 3 months later she started getting lost on her way to the supermarket. Fifth time she got lost we decided to put her in a home for demented people. We simply couldn't provide the care she needed any other way. Took a few more months and she stopped recognising us.
I think she outlived her dog by about 18 months, iirc.
She stopped walking, and then age came fast for her.
Also lots of empirical evidence that dog owners live longer.
https://www.youtube.com/watch?v=ocV7Hpj9keM
While the video is very impressive - my main reaction was to think how incredibly cool that type of dog is. So I eventually ended up getting my own Samoyed and it's been a hugely positive impact on my life.
NB I pretty much like all dogs now - but I love Samoyeds.
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.
After the dog died she only talked to people if they came into her home.
I think the social aspect of her walks was very important for her health too. Like you say, it's all about exercising that noggin',as well as the body!
One day he had a minor operation that left him needing a wheelchair for what we thought would be just a few weeks. But he never regained his strength and was never to walk again, which led to a steep and sudden decline in his mental condition. It was truly devastating to see one of the sharpest people I knew become an angry and confused simulacrum of the man I so admired.
I wish I had realized two things then: First, as you say, maintaining mobility is the crucial to the well-being of the elderly. Second, immediate physical/occupational therapy after a fall or surgery is essential to people at risk of losing mobility. Sadly it wasn't offered to us and we didn't think to ask.
I live abroad to make more money and feed my ego and I only see him 3–4 times a year. On top of that selfishness, every now and then I catch myself selfishly thinking I don’t want to go through that, which makes me feel like an even worst piece of shit.
Life sucks.
Alas, it can be taken away without choice, hopefully not.