All too familiar a feeling when I try to run these days. If I weren't still wanting to orienteer, I doubt I would run anymore.
To be fair, coming back to running after not doing it for a long time is never pleasant, regardless of age.
I have a couple of considerations. The first is that I have no interest in embarking on any sort of "serious" running training again, just doesn't seem worth it at this point in my life. And therefore no orienteering, because to me to me the pleasure that has always come from the sport is from both the navigating and the sense of of at least somewhat quick movement through the terrain. The odds of doing enough running training to get in acceptable condition without getting hurt seems real slim (or nil). And, I suppose, my tolerance for maps drawn/printed such that I cannot read them on the run, that tolerance has pretty much disappeared.
On the other hand, since I both enjoy exercise and think it is good for me, I'd like to keep as many options open for getting exercise as possible. So it would be nice to be able to jog down the hills when out hiking, or go for enough of a casual run to work up a good sweat. So there is the desire to do enough running to be able to retain those possibilities as long as possible. Not quite ready to give up on it yet. But the various aches and pains certainly pose a significant hurdle.
Low impact activities are good when things ache. You're already biking a lot, which is great. Given your proximity to the river, some sort of vessel might be a good option, too.
It's more the suspicion that I am doing myself more harm than good than just the difficulty of it.
You might enjoy "Fast After 50" by Joe Friel, the well known triathlon coach, author and athlete, now in his 70s. I'm in the 50+ demographic too, and it's refreshing to get info that is directly relevant and science-based as much as possible. Major takeaways so far: masters athletes need to focus more on strength/mobility and interval training than younger athletes. The strength/mobility is useful for life in general, not just running. I've added a lot of strength/mobility to my training in the past few years and have found it useful in preventing injuries and resolving random aches and pains. A 30 minute strength session can substitute for the occasional run, and it makes the hills feel so much better. I also include balance exercises in the mix, and that has prevented the odd face plant (but not all!)
I've got his book, and read most of it (mostly out of curiosity). While not disagreeing with your comments at all, I think I'll wait for the sequel "Fast After 70," though it may be a long wait.
In the meantime, the book was just recently put to excellent use -- it was just the right thickness to add to the existing (but not quite sufficient) pile of books being used to counteract a sag in one part of our bed... :-)