My father is in his early 70s. He's been a cyclists pretty much all his life, has done quite a bit of riding, and has ridden some fairly lengthy distances (he did his first 300K just a few years ago). But last year he logged the most km he has ever ridden in a year. And he's not just doddling along smelling the roses. My impression is that his speed has improved in the past few years ...a few years ago, I could drop him quite easily, now I have trouble keeping up with him.