Walking shoes may sound like a marketing conspiracy hatched by shoe-industry executives. After all, it's only walking -- won't any pair of sneakers suffice? Actually, the concept of a walking shoe is valid.

Your walking shoes should have good shock absorption in the heels and in the balls of the feet. They should be a bit stiffer and more supportive than running shoes, although they need to have a very flexible forefoot to allow for the natural bend of the foot. The midsoles will be thinner than those of running shoes in order to accommodate the slower foot roll when you walk. Look for a shoe that features beveled, or slightly angled, heels to allow for a smooth heel-to-toe roll.

Beyond these basic traits, look for a shoe that meets matches your foot type:

• Pronators have feet that roll excessively inward when they walk. Look for a board-lasted shoe (the inside of the shoe is glued rather than stitched in place) that has a motion-control device in the midsole. A straight-shaped shoe, which provides support for the inside of the foot and thus prevents you from overusing the inside edge of your foot, is also preferable. (When you look at the bottom of the shoe it will have very little curve.) Another plus is a reinforced heel for control and stability. Sturdy uppers and stability straps can also help prevent inward roll. Shoes with too much padding can exaggerate pronation, so avoid them.