I need to wear glasses while cycling, and tend to wear Adidas Evil Eyes with the presciption inserts.
I find that both the inserts and the glasses themselves continually get steamed up, especially on slow climbs (which most of my climbs are), and especially in the winter (as you'd expect). It's getting quite annoying, and more than a little dangerous when I start descending and hit techy bits...
I've tried using Fairy liquid, rubbed in with a lint-free cloth. I've tried rubbing candle wax on, then rubbing it in. Neither of them have worked particularly well.
Are there any other techniques that people have had success with. Someone suggested some sort of magic potion that TV cameramen use on the camera lenses to stop them getting condensation, but couldn't remember what it was called.
For the record, I can't use contact lenses, and would love to be able to ride fast enough to keep a breeze flowing through the glasses, but seem unable to do so.