It’s not a well worded response but it’s a valid response.
“Oh I’m focused … You know look, I have trouble even believing how old I am. I don’t give thought to my age any more than I give thought to flying. There aren’t things that I avoid doing now that I did before … physically, mentally, etc.”
Another way of phrasing it, I’m focused … This whole thing is silly, I don’t even think about it. I do all the stuff I did when I was younger now. I’m only old on the outside."