There used to be an old fella at motocross (retired and 66yrs old), he was last every time and was usually lapped by a lot of the field, he wasn't dangerously slow or wobbling about, he was doing ok but he wasn't at race pace.
Some of the lads would take the piss, not to his face, but they'd make the odd comment, and I'd always counter by saying that I hope I'm fit enough at 66 to last a full race distance on a motocross track, I had nothing but respect for the bloke.