If you're serious about bicycling as a sport, sooner or later you're going to get yourself a pair of clip-in pedals. These pedals are so small that they give you more power and less resistance for your pedaling efforts.
When I finally decided to admit to myself that bicycling has become a serious part of my life, I asked around and learned about clip-in pedals and how they hook into the bottoms of special pairs of shoes.
My bicycling friends told me that the quality pro standard then I should aim for was a pair of Crank Brothers brand shoes with egg beater style clip-in pedals. At around a hundred dollars a pair, they're a significant investment, but they've been so worth it!
My egg beater clip-in pedals are made from brushed aluminum and brass. Since they're well-made, they come apart pretty easily to clean off grit and mud.
You can tell when a pair of egg beater clip-ins need cleaning when they start making a creaking noise; I usually get to that stage and need to clean mine after two or three seasons (fall and spring and such, not bicycling seasons) of use. Always clean them before considering replacing them -- they're expensive!