The easiest, most affordable, most convenient form of exercise is walking. Almost everyone can do it and the only equipment you need is a pair of shoes with decent cushioning and a pedometer. Pedometers provide motivation by giving users a simple, measurable daily activity goal to think about and to work towards. Two years ago Stanford University summarized 26 different studies that focused on the use of pedometers. They found that people who use a pedometer walk an additional 2,000 steps per day and tend to increase overall physical activity by 27%.

A good pedometer only costs about $25. There are two different types of pedometers to consider: spring-suspended and piezoelectric. The spring-suspended kind have to be worn perpendicular to the ground (or they're inaccurate), and the piezoelectric kind can be worn at any angle. The spring-suspended kind are usually the cheapest ones.

The first thing you need to do to get started on your daily walking program is to give yourself a daily step count goal. A reasonable, progressive goal is to increase your steps in weekly increments of 500 steps-per-day until you get up to 10,000 steps per day. [Note that 2,000 steps is roughly equivalent of 1 mile]. Keep daily and weekly tallies of your steps.

"Official exercise guidelines say adults should get two-and-a-half hours of moderate-intensity exercise a week, and walking at a pace of 3 mph -- a good clip, but manageable by most -- counts as moderate-intensity exercise."