Almost everyone needs to get more exercise, and walking more may be the easiest way to do it.

You dongt need lessons. Equipment? A good pair of shoes is about all thatgs required. Arthritic knees and hips certainly make it harder, but not impossible if you start gradually and wear shoes with plenty of cushioning.

Official exercise guidelines say adults should get 2z 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.

But knowing all this doesngt necessarily make us walk more. Some exercise researchers say wegre naturally sedentary creatures, evolved to be couch potatoes long before there were couches (or potatoes). Inactivity is often reinforced by living circumstances.

Theregs been a lot of research lately into the health effects of "built environments," and studies have shown that people who live in suburbs and depend on cars to get around get less exercise than those who live in places with sidewalks and nearby shops.

If yougre in a nonwalking inactivity rut, wearing a pedometer might be one of the least expensive and most effective ways to climb out of it. Compared with todaygs smart phones and iPods, pedometers are humble little devices that count the number of steps you take. More elaborate models tell the time, calculate how many calories yougve burned (based on your weight), and keep daily step tallies over an entire week.

Research has shown that pedometers are a good motivational tool, although maybe not by themselves. Several randomized trials show that itgs the combination of wearing a pedometer and having a goal thatgs most effective. A common one is 10,000 steps a day, which is equivalent to about five miles, depending on the length of your stride.

The enthusiasm for pedometers has hit a couple of speed bumps lately. Some studies have shown that less expensive models tend to under-count steps at a slow walking pace and when theygre worn by heavier people, probably because a bulging waistline tilts them at an angle that affects the step-counting mechanism inside. Heavy people would be among the prime beneficiaries of a walking program, so this is a setback for pedometers and some well-intentioned walking programs that depend on the low-cost models.

Getting 10,000 steps a day is a good goal. Walk at a fairly brisk pace of 3 mph to get health benefits from walking.

You can buy a good pedometer for as little as $25. The piezoelectric models that "work at any angle" cost more but may be more accurate and easier to use.

Get up and go

Much of the research has focused on the pedometer as motivator and, by and large, the findings indicate that it is. In 2007, Stanford University researchers took the birdgs-eye view, gathered up 26 different studies and summarized the results in a paper published in The Journal of the American Medical Association. Their synopsis showed that, at least in studies, pedometer users walk more than 2,000 additional steps each day than nonusers, and their overall physical activity levels increase by 27 percent.

Other research has shown that exercise advice given to patients by doctors might be more effective if a pedometer were part of the prescription and that pedometers can be part of a successful program to encourage low-income mothers to exercise.

Can-do exercise

Not every study has been so positive. A British review of interventions to promote walking published the same year as the Stanford review noted that the effect of the pedometer on walking may wane as time goes on — a problem seen with many exercise programs.

Norwegian investigators reported findings in 2008 that found no difference in results for people who wore a pedometer, and those who were instead counseled to increase the amount of time they walked each day. Their argument: It may not be pedometers per se that get people walking so much as regular counseling and having a goal. Thatgs actually quite consistent with something the Stanford researchers discovered: The three pedometer studies that did not include a step goal showed no significant improvement in physical activity.

Few of these studies explored in any depth why pedometers are good motivators. One hunch: A pedometer puts a number to our physical activity efforts, and most of us respond to the concreteness of numbers, especially when it comes to exercise. Runners count miles, and swimmers, laps—and now walkers, with the help of pedometers, their steps.

A step at a time

Some experts invoke the self-efficacy theory as an explanation. In simplified terms, self-efficacy means having confidence that you can perform a task thatgs set before you. What wegre asked to do when we wear a pedometer is to take more steps —not a daunting prospect for the average person. Walking 10,000 steps a day may seem like a lot but it is within reach given that many of us already take between 6,000 and 7,000 steps daily.

Put another way, those additional 3,000 to 4,000 steps add up to about a mile and a half, a distance most of us can cover in about 30 minutes. In busy lives, thatgs not an inconsiderable amount of time, but we can find it, especially when you consider the exercise guidelines that say we can divide up that 30 minutes into 10-minute chunks and still get health benefits.

The average stride is about 2z feet long, although it might be a bit shorter for women, on average, than men because they tend to have shorter legs.

So if you have an average stride and you take 2,000 steps, you will have walked the equivalent of about a mile (5,000 feet, compared with 5,280 in a mile).

And if you hit the 10,000 steps-a-day mark, you will have walked the equivalent of nearly five miles (25,000 feet, compared with the 26,400 in five miles).

A reasonable goal for most people is to increase their average step count each week by 500 per day (a quarter of a mile) until they can average 10,000 a day with ease.