Journal home
Advance online publication
Current issue
Press releases
Guide to authors
Online submissionOnline submission
For referees
Free online issue
Contact the journal
Reprints and permissions
About this site
For librarians
NPG Resources
Nature Reviews
Nature Immunology
Nature Cell Biology
Nature Genetics
Nature Conferences
Dissect Medicine
NPG Subject areas
Clinical Medicine
Drug Discovery
Earth Sciences
Evolution & Ecology
Materials Science
Medical Research
Molecular Cell Biology
Browse all publications
Nature Medicine  11, 363 - 364 (2005)

News Feature: One step at a time

Kendall Powell

Kendall Powell is a freelance writer based in Denver.

Turning the tide on the obesity epidemic is going to require a myriad lifestyle changes—and a few communities are rising to the challenge. Kendall Powell cruises the neighborhood.

Friendly neighborhood: The Stapleton community near Denver, Colorado, offers all the benefits of city living—including sidewalks, parks and outdoor markets—that foster fitness.

Courtesy: Forest City Stapleton, Inc.
On a sunny Thursday morning in February, the Stapleton community ten miles east of downtown Denver is bustling. Moms push strollers to jungle gyms in large playgrounds. A family of three is walking off a big breakfast. A retiree enjoys mountain views from a bench and about 15 dogs and owners romp in the dog park.

The scene might seem unexceptional, but compared to the average suburb where people drive even to the corner store, Stapleton's residents do an inordinate amount of strolling or biking. These residents might also be the lucky few to escape the insidious obesity epidemic.

Many factors have been linked to the obesity epidemic worldwide—genetics, stress hormones, the easy availability of cheap, processed foods, even fewer hours of sleep1 (see Food fights and sleepless nights). In the US, obesity prevalence increased by about 35% from 1994 to 20002. But one factor has crept so gradually into people's lifestyle that, until recently, obesity researchers paid it little notice.

"The way we became a car-dependent society had some implications. We engineered activity out of our lives," says Tom Schmid, a behavioral scientist in the Division of Nutrition and Physical Activity at the US Centers for Disease Control and Prevention (CDC) in Atlanta. The conveniences of modern, affluent living—drive-through windows, suburban sprawl, computer workstations—have drastically reduced physical activity in daily routines, Schmid says.

Schmid and his colleagues have found that people who live in suburbs are more likely to be obese than their urban and walking counterparts. For every additional hour spent driving, a person's likelihood of becoming obese increases six percent3, they found. Their work is part of a growing realization that the environment can hold back even the most determined dieter.

In December 2004, the US government raised the recommended daily fruit and vegetable servings from five to nine and the time spent on moderate activity from 30 minutes to 60−90 minutes per day—high standards for even the fittest among us. But after 20 years of telling patients to eat healthier and be more active, experts note that individual approaches rarely work in the long term. To combat the obesity epidemic, they say, problems must be addressed at the community level.

"We are getting nowhere by yelling louder and moving guidelines up," says James Hill, director of the Center for Human Nutrition at the University of Colorado.

But how can we design activity back into peoples' lives? Researchers spanning the public health, city planning and transportation sectors are coming up with solutions that seem deceptively simple: better bike paths and pedestrian-friendly policies to compete with driving, new communities designed around active living and worksite changes to encourage employees to get up from their desks more often.

The big question remains: will people take advantage of the changes? A few preliminary studies say yes—at least for some part of the population. The National Institute of Environmental Health Sciences in North Carolina plans to evaluate 25 communities like Stapleton during the next five years to see how residents' physical fitness compares to those in 10 control communities. The prospective study will help establish whether there are causal connections between environment, transportation and health, says lead investigator Allen Dearry.

Pounding the pavement
Stapleton, built on the remnants of Denver's old airport, was designed to recreate the best of city living—inviting sidewalks, neighborhood storefronts and economic diversity—with some of the safety, quiet and convenience of traditional suburbs.

The typical American suburb, which evolved during the 'car is king' mentality of the 1960s, built wide streets, cul-de-sacs and garage-in-front housing designs at the expense of parks and walking paths.

Stapleton, in contrast, is four square miles of high-density mixed-income housing, schools, mini-parks, 'main-street' shops and a town green, all connected by sidewalks and greenways. The goal was for the neighborhood paths to lead to real destinations such as the playground, school or grocery store, says Tom Gleason, spokesman for Forest City, Stapleton's developers.

Destinations are crucial for most people to become pedestrians. "We are busy people, we are not going to walk just for the sake of walking," says Lawrence Frank, an expert at the University of British Columbia.

 We are busy people, we are not going to walk just for the sake of walking.  

Lawrence Frank
University of British Columbia
The idea works for Stapleton resident Heidi Crum who frequently walks or bikes with her children to the pool, the farmer's market or to the ice cream parlor in the summer. But Colorado's Rocky Mountains attract people with active lifestyles. What about more couch-bound people? Frank points to two possibilities: funding pedestrian improvements and rezoning to have shops closer to where people live and work.

Fighting inertia

Fringe benefits: The campus of the Sprint Corporation headquarters in Kansas is built to encourage employees to walk.

The Sprint Corporation headquarters in Overland Park, Kansas, was built to encourage more physical activity at work. In 1999, the company worked with architects to design a campus to encourage better employee interactions and improve wellness. The campus has a parking lot that is a five-minute walk away from buildings, elevators that are deliberately slower than taking the stairs, a walking trail and sports fields.

Sprint does not track employee health because of privacy reasons, but spokeswoman Jennifer Bosshardt says people take advantage of the walking path, have dropped pounds by working out with colleagues and even hold walking meetings.

Skeptics might say that for most people, the car culture is far too ingrained to make a difference. A report released in February4 suggests otherwise. In one of the first studies to objectively measure the relationship between neighborhood walkability and a person's physical activity, Frank and his colleagues measured the activity levels of 357 people in the greater Atlanta region using accelerometers worn on the participant's hip, which measure the vertical movement associated with walking. They also calculated a neighborhood's walkability from housing density, street connectivity and land-use mix in a 1-km area surrounding a subject's home.

People in the most walkable regions are 2.5 times more likely to get 30 minutes or more of moderate activity per day than those living in the least walkable regions, the researchers found. But only 37.5% of all people in the highly walkable neighborhoods reached the 30 minutes or more mark. "It's not a prescription for everyone," says Frank. "But there's no question that how we design our communities matters."

Small steps
Those who study exercise motivation say changes to the so-called built environment fit nicely with the types of activities adopted by successful exercisers. The US National Weight Control Registry tracks people who have lost 30 pounds or more and have kept it off for at least one year. Hill, who co-directs the registry, says the overwhelming majority keep weight off by getting plenty of daily physical activity, and not by dieting.

Hill says telling people to make big changes is not sustainable. Instead, he starts people on programs such as America on the Move that begin with small, daily goals like walking an extra 2,000 steps (about a mile) or cutting 100 calories (about one soda). Once people reach 2,000 steps, they are encouraged to add 2,000 more.

Setting realistic goals is key, adds Bess Marcus, professor of psychiatry at Brown Medical School in Providence, Rhode Island. "The number-one barrier to exercise is lack of time or perceived lack of time," she says.

Luckily, she notes, the notion that we need hours of vigorous, spandex-clad exercise at the gym to lose weight is falling by the wayside. Walking can be done all at once or incorporated into everyday activity with the same results, she says. And exercise doesn't have to be boring: moderate activity could be dancing or shooting hoops with the kids.

But can simply taking the stairs more often or parking farther away really stop the waistband from expanding? An analysis of studies from 1970−2003 on physical activity interventions confirms that simple environmental changes, such as easier access to stairs, can promote increased activity5. Hill's 2,000 extra steps would keep off the one or two pounds per year an average American gains; simply monitoring steps with a pedo-meter could stop weight gain in 90% of the population, he says1.

In one of the most controlled studies of its kind, researchers at the Mayo Clinic in Rochester, Minnesota, compared total activity from ten lean subjects and ten mildly obese subjects for ten-day periods6. The lean subjects spent two hours on average more each day doing non-purposeful activity—fidgeting, pacing, going to the water cooler—than the more sedentary, obese volunteers. That extra activity amounted to 350 additional calories burned each day, or roughly 30 pounds over the course of a year.

This means that small, sustained activities of daily life can shift energy balance, says Dearry. "Maybe one of the best approaches to help people stay lean would be to encourage activity and discourage sitting," he says.

Hill describes his successful registry 'losers' as people who have learned to "swim upstream in their obesogenic environment." He suggests that changes to communities or worksites that lower the barriers to physical activity might increase the numbers of people who can succeed.

Encouraging people to drive less is the first step toward getting the daily activity our bodies are designed to handle, Hill says. And while you're at it, you might reduce air pollution and meet your neighbors, too. Go on, take a hike.

Food fights and sleepless nights

  1. Vorona, R.D. et al. Arch. Intern. Med. 165, 25−30 (2005). | Article | PubMed  |
  2. Hill, J.O. et al. Science. 299, 853−855 (2003). | Article | PubMed  | ISI | ChemPort |
  3. Frank, L.D. et al. Am. J. Prev. Med. 27, 87−96 (2004). | Article | PubMed  |
  4. Frank, L.D. et al. Am. J. Prev. Med. 28, 117−124 (2005). | Article | PubMed  |
  5. Matson-Koffman, D.M. et al. Am. J. Health Promot. 19, 167−193 (2005). | PubMed  |
  6. Levine, J.A. et al. Science. 307, 584−586 (2005). | Article | PubMed  | ChemPort |
  7. Milgram, N.w. et al. Neurobiol. Aging. 26, 77−90 (2005). | Article | PubMed  | ChemPort |
Previous | Next
Table of contents
Download PDFDownload PDF
Send to a friendSend to a friend
Save this linkSave this link
More articles like this



Export citation
Export references

Search buyers guide:

Nature Medicine
ISSN: 1078-8956
EISSN: 1546-170X
Journal home | Advance online publication | Current issue | Archive | Press releases | Supplements | Focuses | For authors | Online submission | For referees | Free online issue | About the journal | Contact the journal | Subscribe | Advertising | work@npg | Reprints and permissions | About this site | For librarians
Nature Publishing Group, publisher of Nature, and other science journals and reference works©2005 Nature Publishing Group | Privacy policy