Getting older is like managing the retreat of an Army unit. You know you have to give ground and will eventually lose everything. But in the meantime you want to retreat as slowly as possible, keeping it orderly and preventing a rout. Anywhere you can stand and fight for a while you should if the odds are good enough.
Hence my giving up on squash a year ago but deciding to keep up tennis. After ten months of being unable to play a match I am back on the courts competing, but it takes a lot of exercise, stretching, and rehab to keep the odds of continuing (for decades?) reasonably good.
Then there is our eldest cat Shadow (age 17), for whom the retreat is considerably more advanced. Having already lost his teeth and developed an over-active thyroid that, despite surgery (!), still over-produces enough hormones to kill him if we weren't giving him a pill twice daily plus special food, he now appears to have developed chronic kidney disease. This requires injecting him in the back with fluids once a day, at least for now, I gather simply to slow the ongoing process that might take as long as a couple of years (though then again it might be a lot less). And it requires a change in diet that, I gather, involves retreat on managing the thyroid problem as the kidney issue is more acute.
Despite all the extremely nice cats in the world you can find in shelters that evidently are not finding homes, Shadow is about as good an argument for animal cloning as I have yet met. We adopted him when the men's clothing store he lived in was closing and he started following me around the store when I came back to pick up my garments. Placid, mellow, sweet-tempered, loves people, likes other cats - he makes me proud to be a fellow mammal.
Here he is enjoying the sun, which he may not get to do for much longer.