I must say the martial arts is a fountain of youth. Getting old, at least physically, isn't in our vocabulary.
"Getting old is a right of passage, not to be avoided or feared, but embraced because you simply cannot avoid it while you are still breathing" - me “The man who views the world at 50 the same as he did at 20 has wasted 30 years of his life.” ― Muhammad Ali
My vocabulary certainly includes a lot more grunts and sighs that coincide with movements now I'm in my 50s I think it's important to be realistic; recovery time is just longer as we age. In one way I do agree however; we can be smart about how we train, use our experience and knowledge, and if not rage, certainly offer some resistance to the dying of the light.
If you're like me, you even sit down to pee whenever you get a chance, because it feels nice to plant your tired butt down more than ever, and you groan sitting down and getting back up but it feels like progress. I've been told by more than one physical therapist that the grunts and groans are a sign you've learned to deal with the ache. The people who don't do that, don't even have the same range of movement in their 50's that you probably do. That said, there are a lot of things I have to do now that I didn't use to have to. Avoiding certain foods more, drinking less, not smoking, and exercising regularly all go together. If you ignore any of these it's just going to get worse faster, probably.
Older:::: wiser, fight clever, recover slower, realise that you are no longer that young 20 something able to take on the world martial artist.