Oh ya... Marathons have come and gone for me :) Initially because they were just expensive but COVID had me WFH full time and the group I ran with was near my work office. So I sort of morphed into running alone and just as maintenance vs. Training for something.
I'm about to hit 53 and try to run between 15-20/miles a week still but I did fall behind on my fitness the end of last year when I had some crazy back spasms after sneezing (of all things) that really set me back. Takes forever to get back. Luckily I do not have any physical issues (knees etc) most if my issues now are not eating healthy enough and general motivation to improve. Sounds like I've got about 7 years to get on top of it so I can cruise through that age too :)
I literally could not get off the floor for around 2h and was panicking quite a bit. Never ever felt so vulnerable before. Do not recommend whatever happened to me :). Good thing is it was just muscle and once healed I was back to 100% It just prevented me from running for over a month.