"Our major result is pedometer users increased their physical activity," says Dena Bravata, MD, senior research scientist at Stanford University School of Medicine and a doctor in private practice in San Francisco. With her colleagues, she analyzed 26 published studies on the devices and the effect they have on increasing daily physical activity.
Those who wore the devices also reduced body weight and blood pressure , she and her colleagues report in the Nov. 21 issue of The Journal of the American Medical Association.
In all, the studies followed 2,767 participants, 85% of them women, with an average age of 49. They participated in the pedometer and activity research for about 18 weeks, on average.
Wearing the pedometer boosted their physical activity. "Specifically they increased it by about 2,000 steps a day, or about a mile," Bravata tells WebMD. That's roughly burning about 100 more calories.
The Importance of a Goal
But the goal part of the equation is crucial, she says. "Those studies that provided subjects with a pedometer but did not ask them to meet a goal did not result in an increase in physical activity," Bravata says. "Having a step goal is a key component of [increasing] physical activity when using a pedometer."
A total of 10,000 steps a day, or roughly 5 miles, is often recommended as a goal when wearing the devices. The total includes "purposeful" exercise
as well as routine activity such as walking through the grocery store.
But the specific goal is not as important as having one, Bravata tells WebMD. "We found that having any goal - be it 10,000 steps a day or another - led to significant increases in physical activity."
Pedometers Cut Weight and Blood Pressure
Pedometer users also had reductions in weight and blood pressure, Bravata
found. The initial body mass index or BMI of the study participants averaged 30, which is considered obese. "Their average weight loss reduced their BMI by about 0.4," she tells WebMD.
"Losing a BMI of 0.4 may not seem like that much to you," she says, but it was enough to get them out of the obese category in some cases, thus reducing some health risks.
On average, the systolic blood pressure (the upper reading) decreased by 3.8 points, Bravata also found. "That is a dramatic finding I think for two reasons," she says. "Those whose blood pressure reduced the most had the highest [to begin with]."
The new review makes sense, especially the part about needing a daily goal, says Cherilyn Hultquist, PhD, a visiting assistant professor of exercise physiology at the University of Tennessee Center for Physical Activity and Health.
"Even if you don't hit your goal, you are probably going to walk more than if you didn't have one," she says. Her study was one of the 26 reviewed by Bravata.
Bravata says she was inspired to do the research so she could provide a scientific and accurate suggestion when her sedentary patients ask her how to boost their activity.
"I didn't recommend pedometers before," she says. She hesitated, she says, because she wanted to review the evidence. "Now I definitely do. I recommend them to my sedentary patients. I have them keep a diary [of their daily steps] and bring the diary in and we review it."
As the new analysis shows, the pedometer works best for those who are sedentary or in the low-to-moderate activity level, says Karen Croteau, EdD, associate professor of exercise, health, and sport sciences, University of Southern Maine, Gorham, whose research was also included in the new report.
"People who are already active don't necessarily need it," she says.
"They might be curious about how many steps they are gettin. If they are already active, it isn't going to boost their activity that much."
Spend about $10 or $15 for a good, basic pedometer, Croteau suggests. "Line it up above your hip bone, a little to the right of where a pant crease line would be," she says. "Then test it. Take 20 steps to see if it records."
By Kathleen Doheny
Reviewed by Louise Chang
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