Pedometers motivate people to exercise, reports the Harvard Health Letter

Walking is one of the easiest ways to get exercise. If you're in a nonwalking rut, wearing a pedometer might be one of the least expensive and most effective ways to climb out of it, reports the September 2009 issue of the Harvard Health Letter.

A pedometer is a good motivational tool, although maybe not all by itself. Several randomized trials show that what's more effective is the combination of wearing a pedometer and having a goal. A common goal is 10,000 steps a day, which is equivalent to about five miles, depending on the length of your stride.