Even as we learn more about the health benefits of moderate exercise such as walking, we're finding that such a common everyday activity may not be as easy, or as safe, as it seems.
A study published earlier this month in the Journal of the American Medical Assn. found that post-menopausal women who walked four or more hours a week had a 41% lower risk of hip fractures compared with those who did little or no exercise. The study found that among women who exercised the most, eight or more hours a week, the reduction in the risk of a hip fracture was essentially the same as taking hormone replacement therapy.
In fact, any exercise -- even standing, as opposed to sitting -- reduced the risk of hip fracture, said the study's lead author, Diane Feskanich, an assistant professor at Brigham and Women's Hospital in Boston.
The study, part of the ongoing Nurses Health Study, included 61,200 post-menopausal women ages 40 to 77 who were followed from 1986 to 1998. Those women who stood 55 hours a week or more had a 46% lower risk of hip fracture compared with couch potatoes.
"One could say that doing anything rather than sitting and watching TV will help," Feskanich said. "The point is, you get more benefit the more you do."
Standing 55 hours or more a week sounds a little tough, but walking or some other form of exercise isn't. And it's good for so much else: It reduces the risk of heart disease and stroke by lowering blood pressure and raising HDL, the so-called "good cholesterol." It helps with weight control and reduces the risk of Type 2 diabetes. It helps with balance and flexibility. It helps reduce the pain from joint problems. It can improve the quality of sleep. It often reduces the symptoms of depression, and a recent study showed it helps keep older people mentally sharper.
There's no down side to moving your body "unless you overdo it, and we're not talking about that," Feskanich said.
Experts admit one of the reasons more people don't walk or exercise is that many of us live in places where it's not easy to do. Many communities today are designed to accommodate travel by car rather than by foot or bicycle.
Census figures show that the number of people living in sprawling suburban areas -- where there may be no sidewalks, and shopping areas and schools can be miles away -- grew by 18% in the last decade, while the number of people living in cities -- which have sidewalks and shopping that encourages walking -- grew by 8%. That can lead to safety problems too. About a quarter of all people killed in traffic accidents are pedestrians, according to the Surface Transportation Policy Project, a coalition of national groups working to increase alternatives to driving.
Ellen Vanderslice, president of America Walks, a coalition of 48 groups, said that although a 1991 transportation act increased the amount of funding that could go to building more pedestrian-safe areas, actual funding patterns -- and philosophies -- have been slow to change.
"There needs to be places for people to walk, to cross the street. Those are things that are often overlooked by engineers," she said. Planners still too often see pedestrians as impediments to traffic, which, she said, is ironic, considering "impediment" means "hindering the foot."
The Department of Transportation and the National Safety Council have put together a checklist you can use to assess your own neighborhood's walkability: Do you have room to walk? Is it easy to cross streets? Is your walk pleasant or unsafe? Is it full of scary dogs or litter? (You can find the checklist at www.nsc.org/walk/wkcheck.htm.)
Once you have assessed your neighborhood, the department offers things you can do to improve it, ranging from telling your city's engineering or public works department about problems to speaking up at government board meetings about the need for safe places to walk.
There are also government and volunteer groups that can provide information. The point is to get out there and move. Here are some contacts:
The U.S. Centers for Disease Control and Prevention's Division of Nutrition and Physical Activity, (888) 232-4674, www.cdc.gov/nccdphp/dnpa/readyset.
America Walks, (503) 222-1077, www.americawalks.org.
Partnership for a Walkable America, National Safety Council, (630) 285-1121, www.nsc.org/walkable.htm.
National Safe Kids Campaign, (202) 662-0600, www.nhtsa.dot.gov.
University of North Carolina Pedestrian and Bicycling Information Center, (919) 962-2202, www.walkinginfo.org.