If you're worried about your coach, wear both Seriously though, DD wears prescription safety glasses with transition lenses under her helmet. You might want to think about those as opposed to contacts for several reasons. 1) Don't have to worry about dirt in the eye. 2) More scratch resistant than ordinary glasses or sunglasses. 3) Will automatically tint/adjust according to available light. 4) Most importantly, gives you a legitimate reason to wear sunglasses under your helmet without giving your coach even an inkling that you're disregarding her opinion.