THURSDAY, Jan. 24, 2008 (HealthDay News) -- Just by strapping on a step-counting pedometer, overweight or obese "couch potatoes" who start a daily walking regimen can expect to lose at least a modest amount of weight -- even in the absence of any special diet, new research reveals.
The review of data from nine studies found that patients who used a pedometer to track and motivate their walking achieved a loss of about a pound every 10 weeks.
"The main point is that pedometer-based walking programs are effective at getting people to walk more, and they do result in a modest amount of weight loss," said study lead author Dr. Caroline R. Richardson, an assistant professor in the department of family medicine at the University of Michigan Medical School in Ann Arbor.
"It's not a huge response, but it's not no response -- it's a modest response," added Richardson, who also serves as a research scientist in the Health Services Research and Development Center at Ann Arbor Veterans' Affairs Medical Center.
The findings are published in the January/February issue of the Annals of Family Medicine.
Simple, inexpensive and pager-sized, pedometers are worn at the waist to automatically keep track of every step the wearer takes while walking, running, climbing, dancing, or engaging in a variety of sports.
According to experts, pedometer users may gain some flexibility as they set exercise goals -- for example, they can meet their target in a single daily outing or through several short outings spread across the day. In this way, pedometers may help encourage more people to exercise, fitness experts say.
But others question that theory.
To help settle the debate, Richardson's team analyzed data collected in nine pedometer-based walking studies conducted between 1995 and 2006.
In each study, 307 previously sedentary and overweight or obese patients were motivated to join a new walking program by using pedometers to monitor their total daily step counts.
Study size varied from 15 to 106 participants each, and almost three-quarters of the patients were women. Special diets were not included as part of the studies.
Nevertheless, the researchers found what they called "remarkably consistent" results. With the exception of those participating in one of the studies, all of the enrolled patients ended up losing a small amount of weight by each study's end.
On average, participants lost about a tenth of a pound per week -- an amount the authors described as "small but important." They noted that over the course of a year, this figure translates into an expected weight loss of five pounds.
Such weight loss resulted from an average step count increase of between 2,000 to 4,000 steps (one to two miles) per day per participant over the course of each study.
Assuming a walking pace of three miles per hour, such increases were calculated to be the equivalent of an additional 20 to 40 minutes of walking per day.
Richardson and her colleagues also noted that the longer the program lasted, the greater the ultimate weight loss.
Weight loss was modest for most participants, the researchers stressed. However, pedometer-based walking programs should confer significant health benefits beyond weight loss, including lowered blood pressure and a boost in cardiovascular health.
Those coping with type 2 diabetes or glucose intolerance may also reap related health rewards, Richardson's group noted.
"There are other things you can achieve as well," noted Richardson. "You can get stress relief, you may sleep better at night, have an improved mood. And focusing your motivation on some of these other changes may help you stick with the program. And if you stick with walking, you may eventually get the weight reduction goal you're looking for."
Alice H. Lichtenstein is director of the Cardiovascular Nutrition Lab in the U.S. Department of Agriculture's Human Nutrition Research Center at Tufts University in Boston. She was encouraged but not surprised by the findings.
"There's something about a pedometer that makes a difference," said Lichtenstein, who is also a former chair of the American Heart Association's nutrition committee.
"Perhaps the pedometer is reinforcing behavior change," she speculated. "With some people, it gives them a goal. For others, it serves as a reminder. And, of course, anyone who's made a commitment to wear a pedometer has likely made some sort of internal commitment to stick with the exercise program. And this is a way you can look and check and see how you're doing. And that's instant gratification."
For more on pedometer use, visit the U.S. National Institutes of Health, Division of Nutrition Research Coordination.