Does the Built Environment Influence Physical Activity? Examining the Evidence -- Special Report 282 (2005) / Chapter Skim
Currently Skimming:
3 Long-Term Trends Affecting Physical Activity Levels
3 Long-Term Trends Affecting Physical Activity Levels
Pages 59-84
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 59... ...
Researchers are immediately confronted, however, with the lack of direct measures and longi tudinal data even on changes in physical activity levels -- the pri mary variable of interest. Until 2001, for example, major public health surveys tracked data on leisure-time physical activity only, and reliable data were not collected until the 1980s.
|
From page 60... ...
However, labor force data that enable oc cupations to be classified by activity level can be used to trace occupational changes from 1950 to 2000. From these data, one can draw inferences, at least at a gross level, about changes in physical activity levels in the workplace.
|
From page 61... ...
. In 1990, approximately 24 percent of adults met recommended physical activity levels and in 2000, about 26 percent -- a compound average annual growth rate of 0.75 percent.
|
From page 62... ...
adult population meeting recom mended physical activity levels or reported as inactive.
|
From page 63... ...
. The percentage of students attending physical education classes daily -- an indicator of physical activity levels- declined sharply during the first half of the decade, but increased gradually thereafter (Figure 3-3)
|
From page 64... ...
Employment and Occupational Changes Between 1950 and 2000, the surge of women into the workforce, the continued decline in agricultural employment and manufacturing jobs, and other technological and social changes conducive to the growth of white-collar jobs brought about profound changes in physical activity levels in the workplace.
|
From page 65... ...
; invented with invented TV computer sold 6, Web/Internet first tuners cathode-ray circuit invented television PC created June home Wide radio stations successful scheduled wireless computer recorder sed IBM States first television first first network computers first integrated microchip first microprocessor Apple first World language acces different invented picture United circuits cassette and Communications 1916: 1923: 1927: 1939: 1949: 1951: 1955: 1958: 1959: 1968: 1971: 1976: 1981: 1990: Systems the Act Act first intro invented invent built com tractor Inter- (inventors.about.com, Road the California States service Use for airplane the invented in the improves and to Highway mover of trucks invented of system Supporting Land United escalator Brothers Ford sold airliner line, signal and engined Mack is Federal-Aid freeway jet passenger people the and T engine in Communication Pasadena highway of modern Wright first invention first Henry first traffic jet first Angeles Levittown first Federal-Aid beginning first the assembly Model from Los mercial and state duced History Transport 1900: 1903: 1904: 1906: 1908: 1916: 1923: 1930: 1940: 1949: 1952: 1956: 1963: Innovations oven press electric cleaner auto- invented Transportation, food of first automatic and mix processor McDonald's; dinner dryer invented History Production/Food vacuum frozen microwave cake 1925: first TV permanent food Technological invented invented washer, washer, matic invented first introduced fabric invented Home 1901: 1923: circa 1946: 1949: 1954: 1964: 1971: 19001999, pro auto indus- invented Inventions elevators first photocopier introduction robot word first matic invented of trial cessor wentieth-CenturyT Work 1950: 1958: 1962: 1972: 3-1 lavretnI Twentieth-Century e TABLE miT 19001925 19261950 19511975 19762000 SOURCES:
|
From page 66... ...
It is not possible to characterize the occupations of the remain ing 59 percent of the eligible labor force or to disaggregate the data by gender or other demographic variables. Nevertheless, the avail able data show major shifts in the tails of the distribution, which suggest a generally downward trend in physical activity levels in the workplace.
|
From page 67... ...
Changes in Household Activities The sharp increase in women in the labor force, along with the in troduction of labor-saving technology improvements in the home, has resulted in major changes in the time and energy devoted to household production. These changes in turn have important im plications for physical activity levels.
|
From page 68... ...
In 2001, re spondents to the household interview for the National Household Travel Survey (NHTS) reported that, for the first time, the number of personal vehicles per household (1.9)
|
From page 69... ...
Comparable data for 19902001 alone show a growth in 5 Data from the 1969 survey were not included because walking and bicycle trips were not sampled, so the shares of motorized travel were artificially inflated. Data from the 2001 survey were not in cluded because of a change in sampling methods that captures previously unreported walking trips (Pucher and Renne 2003)
|
From page 70... ...
the average time spent driving from 49 to 62 minutes per day (Hu and Young 1999) .6 Corresponding to the growth in personal vehicle travel, non motorized travel -- primarily walking and cycling but also trips on public transportation that require some walking or cycling to access rail stations and bus stops -- has declined over time (Figures 3-5 and 3-6)
|
From page 71... ...
. The importance of nonmotorized travel also varied by trip pur pose.
|
From page 72... ...
The following sections ex amine other factors that may help explain this decline, including trends in the spatial distributions of population and employment and in time use, particularly the growth in sedentary activities. TRENDS IN SPATIAL DISTRIBUTIONS OF POPULATION AND EMPLOYMENT In examining the built environment as a possible explanation for at least some of the observed decline in physical activity levels, the focus is often on the effect of low-density development on the proximity of travel destinations, which in turn influences trans portation choices.
|
From page 73... ...
By 2000, this number had more than doubled, largely at the expense of nonmetropolitan areas; central cities have maintained their current share of the population -- approximately 30 percent -- over a long period of time (NRC 1999) (Figure 3-7)
|
From page 74... ...
. Minority and poor populations live disproportionately in central cities rather than in suburbs, a situa tion reflecting racial as well as economic segregation (NRC 1999)
|
From page 75... ...
First, geographic characterization of the spatial dimensions of the built environment according to central cities, suburbs, and nonmetropolitan areas falls short of capturing the complexity of urban settings (e.g., ghetto neighborhoods in inner cities, inner suburbs, "edge cities,"13 exurban areas) and the ways in which these differences may affect residents' propensity to be physically active.
|
From page 76... ...
Selected Access Measure Central Cities Suburbs Outside MSAs (%) Housing units with public elementary school <1 milea 72 54 40 Housing units with public transportationb 82 52 23 Housing units with shopping <1 mileb 77 62 41 NOTE: MSA = metropolitan statistical area.
|
From page 77... ...
The effect on physical activity levels of the recent move of poor and minority populations to the inner suburbs is likely to be mixed. The inner suburbs of older cities are apt to look much like their downtowns, with sidewalks and transit service.
|
From page 78... ...
15 Data from the National Human Activity Pattern Survey conducted in 19921994 were used to es timate and rank the energy expenditure for each activity. Survey respondents reported activities in their own words for a 24-hour period, including the location and duration of the activity.
|
From page 79... ...
Bureau of the Census, the ATUS will provide a consistent and continuous source of nationally representative daily time-use data that can readily be combined with demographic and employment data, as well as data on energy expenditure.16 On an "average day" in 2003, persons in the United States aged 15 and older reported that they slept about 8.6 hours, engaged in leisure and sports activities for 5.1 hours, worked for 3.7 hours, and spent 1.8 hours doing household activities.17 The remaining 4.8 hours was 16The ATUS was administered to an outrotated panel of the Current Population Survey, thereby providing demographic and labor force information. Data collection began in January 2003, and the ATUS estimates for that year are based on interviews of about 21,000 individuals.
|
From page 80... ...
To estimate time spent on travel, particularly on active travel, that is, on walk ing, cycling, and accessing public transit, a detailed analysis of the 1995 NPTS was conducted by one of the committee members. The results show that, on average, adults (persons 18 years and older)
|
From page 81... ...
1999. Summary of Travel Trends, 1995 Nationwide Personal Transportation Survey.
|
From page 82... ...
Center on Urban and Metropolitan Policy, Brookings Institution, May. Massey, D., and N
|
From page 83... ...
, a re sult confirmed by the public health surveys reviewed in Chapter 2. The barriers to meeting adequate physical activity levels include personal reasons (disabilities and other health impairments)
|
From page 84... ...
Opportunities to modify the built environment to make it more conducive to physical activity are numerous, but the ease or diffi culty of such changes depends on the intervention. For example, overturning long-standing zoning and land use ordinances to in crease development density and mixed land uses is likely to face formidable barriers that cannot easily be overcome.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.