I now know that it means the age at which one shouldn't be getting none

That double negative is throwing me a curve but I presume you are speaking for yourself?

Lemme tell ya' -- the closer you get to 90, the younger it looks.
Or as someone (?) once said "Eventually I became old, but it was a lot later than I thought."

Then there's the saying that gives me a chuckle : "If I'd known I was going to live this long, I'd've taken better care of myself! Tooooo true.