Health and Community Design

The Impact of the Built Environment on Physical Activity

By Lawrence D. Frank, Peter O. Engelke, Thomas L. Schmid

ISLAND PRESS

Copyright © 2003 Lawrence D. Frank and Peter O. Engelke
All rights reserved.
ISBN: 978-1-55963-917-0

Contents

ABOUT ISLAND PRESS,
Title Page,
Copyright Page,
Table of Figures,
List of Tables,
PREFACE AND ACKNOWLEDGMENTS,
CHAPTER ONE – Introduction,
CHAPTER TWO – Public Health and Urban Form in America,
CHAPTER THREE – Physical Activity and Public Health,
CHAPTER FOUR – Physical Activity,
CHAPTER FIVE – Physical Activity,
CHAPTER SIX – Understanding the Built Environment,
CHAPTER SEVEN – Transportation Systems,
CHAPTER EIGHT – Land Use Patterns,
CHAPTER NINE – Urban Design Characteristics,
CHAPTER TEN – Application of Principles,
CHAPTER ELEVEN – Conclusion,
APPENDIX – Summary of Selected Traffic Calming Studies,
ENDNOTES,
GLOSSARY,
REFERENCES,
ABOUT THE AUTHORS,
INDEX,
ISLAND PRESS BOARD OF DIRECTORS,

CHAPTER 1

Introduction

We ought to plan the ideal of our city with an eye to four considerations. The first, as being the most indispensable, is health.

ARISTOTLE, Politics (ca. 350 B.C.)

Community design influences human behavior. The ways that cities, suburbs, and towns are designed and built impact the people who work, live, and play in them. The placement, layout, and design of transportation systems, of office complexes, of parks, and of the countless physical elements that make up communities result in real places that have real significance in terms of how we spend our time and what activities we engage in. Where people live, where they work, how they get around, how much pollution they produce, what kinds of environmental hazards they face, and what kinds of amenities they enjoy are a direct product of how communities are designed. This book is about how our communities influence one important type of behavior, physical activity, and the health outcomes that are associated with it.

Unfortunately, the great majority of Americans do not get enough physical activity to maintain their health over the long run. Physical inactivity is an enormous health problem in this country, contributing to, among other things, premature death, chronic disease, osteoporosis, poor mental health, and obesity. The environments in which most people spend their time—the modern American city and the suburbs and exurbs that have been the dominant form of development in this country for over a half century—are an important contributor to this problem. The cities and suburbs that we inhabit are not now, and have not been for a long time, places that encourage some critically important forms of physical activity. In short, our physical environment inhibits many forms of activity, such as walking, and has become a significant barrier to more active lifestyles.

A century ago, American cities were highly walkable places. They were compact. Commercial, retail, and even industrial operations existed in close proximity to housing, allowing people to walk to work or school or the store. Out of necessity, buildings and streets were designed to the human scale. Streetcar and trolley systems provided a major form of transportation for millions of passengers every day, in every major city in the nation, which meant that people had the means to make longer journeys without the use of a car. When combined, all of this produced environments in which someone could satisfy their basic daily needs within a comfortable walking distance of their home or within a distance reachable through a combination of walking and trolley riding.

Unfortunately, the burgeoning cities of the industrial era also brought with them a host of serious problems. They were dirty and polluted. They were crowded. Most importantly, they produced health problems for their inhabitants. The worst of these were the communicable disease epidemics—typhus, yellow fever, and all manner of other infectious diseases—that swept through them with frightening regularity. The very conditions that made the industrial city a highly walkable place, including its concentration of people, its mixing of uses, and its high density of buildings, came to be blamed—not quite accurately, as research eventually showed—for creating the conditions in which epidemics could occur. So during the nineteenth and early twentieth centuries, critics tore away at the intellectual foundation of the compact industrial city. They sought to replace it with a new paradigm, a new way of thinking about how to build cities. In the old city’s place they created the modern decentralized city, where housing was separated from workplaces and buildings placed far apart from one another, separated by expanses of grass and trees. America’s new cities of big lawns and big distances would, they hoped and expected, produce more healthy living. What resulted was the city that we are so familiar with today—dominated by suburbs, spread out, with different uses separated one from another and almost everything reliant on automobile travel. This mass suburbaniz ation also led directly to a decline, in terms of population, wealth, and public investment in the older, established central parts of most cities, resulting in the widespread abandonment of the fabric of the old walkable city.

Widespread criticism of this development model has appeared only during the last couple of decades. Much of it is a reaction to the omnipresent automobile congestion that is the hallmark of the decentralized city. Some of it is centered on the monstrous-yet-monotonous ugliness of the endless strip malls and parking lots that have proliferated from one end of the country to the other. Many people are concerned about the environmental consequences of the modern city. These concerns focus on the enormous amount of land consumed, the air quality problems produced by all of the cars needed to keep these cities running, the vast quantities of municipal water that is required to irrigate the lawns of the new suburban landscapes, or the rainwater that is wasted as polluted runoff from parking lots and streets. An even more recent source of criticism is from the field of public health, which is beginning to explore potentially uncomfortable linkages between the decentralized city and different indicators of health.

Physical Activity, Past and Present

In the old cities, getting enough physical activity during one’s day wasn’t an issue because it was as much a part of life as eating or sleeping. Today, physical activity has been engineered out of most aspects of life. Work is no longer physically demanding for most people and daily living patterns, from mowing the grass to cooking dinner to washing clothes, require significantly less manual effort than they once did. The modern city has changed all of this, creating environments in which it is less and less common to work physical activity into the everyday patterns of life. The dominant forms of community design have contributed to this decline by making walking and cycling for transportation difficult if not impossible. Many of the reasons why are clear to even the casual observer. Long distances between places mean that most people cannot walk or bicycle from one place to another. The streets and roads that connect these far-flung places are designed for cars, often making them unsafe and extremely unattractive for pedestrians and bicyclists. To make matters worse, most developers and retailers have long given up on the profitability of designing places that are visually attractive to people who might want to walk from place to place, favoring instead designs that attract motorists. As a result, being physically active now requires planning for activities such as running, biking, aerobics, or weight lifting that can be done during leisure time.

Coincidentally, during the post–World War II period, public health research came to focus more and more on recreational and vigorous physical activity as the way to improve public health. For years, health experts recommended that each individual get at least twenty minutes of high-intensity exercise each day. The basic idea was that anything less would result in little or no improvement in long-term health. And, judging by the attention paid to such forms of exercise in the popular media, it would seem that vigorous physical activity has been a runaway success. Specialty magazines devoted to participatory sports and exercise programs ranging from running to weight lifting to climbing jam the racks at newsstands. An array of televised sports occupies much of the country’s attention on weekends, bringing basketball, football, hockey, baseball, and a slew of other offerings into millions of homes. Advertisers in the print and electronic media perpetually barrage the country with images of the perfectly fit human figure, both male and female.

Yet this picture of a fit and healthy society is enormously misleading. The fact is that most Americans don’t get enough physical activity to meet the health recommendations set by public health agencies. Despite the omnipresence of televised sports, the billions of dollars in exercise equipment and apparel sold every year, the millions of words published on fitness and exercise regimens, and the endless rhetoric springing from athletic shoe and apparel companies’ advertising campaigns, only about five percent of the population—one person in twenty—gets enough physical activity through vigorous exercise to satisfy public health standards (CDC 2001b). Even worse, some studies have found that as much as 40 percent of the population is sedentary (being completely inactive) (Schoenborn and Barnes 2002); they report that they get no physical activity at all during their leisure hours. For all of the promotion and attention paid to sports- and gym-based exercise as the way to get people physically fit, the great majority of the population has not succeeded in becoming physically active through these means. While millions of people do get a great deal of health benefit as well as personal satisfaction from sports, from training for endurance and strength events, and from going to the gym for a workout, many more find that they don’t have the will or the ability or the time or the resources to do any of these things.

These are some of the reasons why, beginning in the 1980s and continuing into the 1990s, public health agencies and researchers began to take a serious look at more moderate types of physical activity such as walking and bicycling. Mounting evidence from epidemiological studies began to reveal that moderate forms of physical activity could provide both short- and long-term health benefits, contributing to a reduction in the risk of premature mortality, chronic disease, and a host of other maladies. Moreover, public health researchers began to believe that a focus on more moderate forms of physical activity might enable a broader cross-section of the population to become physically active. Because moderate physical activity is lower in intensity, it is easier for a person who is sedentary to begin and to maintain their participation over the long term. Moderate physical activity can be purposive, meaning that it can be integrated into daily living habits, and as a result it should be more attractive to people who don’t have the necessary free time to work out at a gym or go mountain biking in the woods.

What is old, then, is new: public health agencies now endorse those forms of moderate physical activity such as walking and bicycling that used to be very commonplace in American cities and towns. Public health officials recommend that people accumulate at least thirty minutes of moderate activity on most, preferably all days of the week. Adding any additional amount of moderate activity is good; in fact, while public health agencies recommend trying to get at least thirty minutes per day, there is a belief that even ten or twenty additional minutes per day might generate some benefits. Vigorous physical activity is still considered to be an important means of staying healthy, but public health experts now believe that adding a half hour or more of moderate physical activity per day on most days of the week is enough to generate long-term health benefits.

This consensus opinion carries enormous significance for addressing the problem of physical inactivity. It suggests—perhaps demands—that public health agencies not limit themselves to programs that rely solely on motivating individuals to take up vigorous exercise. Rather, the door has been opened for an examination of the environmental influences of moderate physical activity. If one needs a half hour or more of moderate physical activity per day, accumulated in numerous short bouts, it might be wise to focus on creating environments that allow these types of activities to occur as a matter of course, as incidental to doing other things. For many people, perhaps even the majority of the population, such an approach may be the only realistic way to increase physical activity (incidentally, increasing physical activity in this way may also be a way to reduce automobile use and lessen its attendant problems, such as air pollution and congestion). For different segments of the population who are disadvantaged—many elderly and physically handicapped people, for instance—vigorous activities may be out of the question completely. For physically capable people in the prime of life, other obstacles such as a lack of time may severely constrict their ability to work out on a regular basis. For the significant percentage of the population that is sedentary, the benefits of adding a half hour of moderate physical activity each day is enormous: physical activity follows a dose-response curve, wherein the marginal benefits to increased exercise accrue the most to those who are the least active to begin with (see chapter 3).

Community Design, Physical Activity, and Health: A Conceptual Model

Figure 1-1 provides a simple model of the relationships between physical activity, health, and the environments in which people live and work. This is the basic conceptual model for the chapters to follow. Causality flows, roughly, from the built environment (the communities in which we live and environments in which we work) through physical activity patterns to public health outcomes. Physical activity is at the literal as well as conceptual center of the model, providing the linkage between the real, built environment and the health outcomes that are of such concern to public health officials.

The built environment denotes the form and character of communities. It is made up of the countless specific places—homes, streets, offices, parking lots, shopping malls, restaurants, parks, movie theaters—that constitute a city or town or suburb. Our model utilizes three broad categories—transportation systems, land use patterns, and urban design characteristics—to provide coherence to the built environment. Transportation systems connect places to each other, determining how feasible it is to use different types of transportation, including walking and bicycling, to get from one place to another. Local transportation systems are impacted by major investments in highways, airports, and other infrastructure decisions made by regional and state officials. Land use patterns consist of the arrangement of residences, offices, restaurants, grocery stores, and other places within the built environment. The arrangement of these activities, or land uses, determine how close different places such as housing, work, and entertainment are to one another, thereby making journeys on foot or by bicycle practical or impractical. They also shape physical activity patterns through the distribution of open space and recreational facilities where sports and other activities can take place. Finally, urban design characteristics influence how people perceive the built environment. Design plays a large role in determining whether an environment is perceived as hostile or friendly, attractive or ugly, and vibrant or dull. Urban design denotes small-scale features of the built environment that impact how people feel about being in specific places.

The conceptual model provided in figure 1-1 illustrates the interactive nature between one’s health and the environment in which one lives, works, and engages in other activities. The arrows that run in both directions between physical activity and health denote how physical activity is both a cause and an effect. The arrow extending from public health to physical activity reflects the likelihood that some health outcomes, such as high levels of obesity or chronic disease in the population, may make it harder for some people to engage in physical activity. Basically, the poorer the health of the population, the more difficult it becomes to increase physical activity levels. However, our central focus is on how the built environment influences physical activity levels.

This leads to a second observation on causality in the model: physical activity is only one contributor, albeit a very important one, to health outcomes. There are, of course, many other reasons why people suffer from ill health. To take one example, during the 1990s and into the new century, the high rates of obesity in the United States became the focus of much research within public health circles as well as a favorite subject of the press. Obesity has multiple causes, ranging from genetics to poor diet to environmental factors and personal behavior. While one’s genetics are an important determinant of obesity, diet and physical activity are things that can be controlled. The built environment impacts both of these behaviors. (While we focus on physical activity in this book, the location of quality food outlets versus fast food venues is another way that the built environment impacts our health; in poorer parts of cities, for example, there tend to be fewer food establishments—restaurants and grocery stores—serving healthy foods.) As tempting as it is to point to the built environment as a main cause of problems such as obesity, it is not acceptable to draw a straight line between the two and imply that only environmental improvement will solve the problem; clearly there are other determinants of obesity.

(Continues…)Excerpted from Health and Community Design by Lawrence D. Frank, Peter O. Engelke, Thomas L. Schmid. Copyright © 2003 Lawrence D. Frank and Peter O. Engelke. Excerpted by permission of ISLAND PRESS.
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.