Somehow I seem to be posting a lot on knees! It is just that I keep coming across articles on knee health that I think are useful; plus I know a few people - especially older hill walkers - whose knees give them trouble.
I've noted previously how balance training can help prevent ACL injuries and how appropriate stretching may also be beneficial.
This article explains that exercise itself is beneficial to the joints.
Among the notable findings, both baseline and current vigorous physical activity— exercise that gets the heart pumping and the body sweating—were associated with an increase in tibial cartilage volume, free from cartilage defects. What’s more, tibial cartilage volume increased with frequency and duration of vigorous activity. Recent weight-bearing exercise was also linked to increased tibial cartilage volume and reduced cartilage defects. Finally, moderate physical activity, including regular walking, was associated with a lower incidence of bone marrow lesions.
The article is also referred to here.
I was thinking about this and how it fits in with a sort of template that I have been considering. I sort of filter all this stuff through a lens of thinking "is this what we were designed for?" I suppose it is a bit like DeVany's Evolutionary Fitness or Sisson's Primal Health. If you have a paradigm within which to work I think it helps you pull diverse ideas together. So I apply this question to think about diet - what to eat and how often - exercise, stress, social pressures, spirituality....
Well, I think we were designed to be active, to move. In that context, of course regular exercise is good for you, of course there will be benefits for your joints. Move, walk, sprint....It is what you were designed for.