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Regular physical activity and high levels of physical fitness offer numerous health benefits, such as reduced risk for cardiovascular disease, diabetes, obesity, some cancers, and musculoskeletal conditions.1 National rates for participation in leisure-time physical activity are consistently low for women, older adults, persons with low educational attainment, and racial/ethnic minorities.2 Public health recommendations for promoting physical activity emphasize moderate-intensity activities, building on recommendations for vigorous exercise to improve fitness.3,4 To determine the prevalence of leisure-time and occupational physical activity, data were analyzed for employed adults aged greater than or equal to 18 years in the 1990 National Health Interview Survey (NHIS). This report summarizes the results of the survey, which indicate that approximately half of adults who reported no physical activity during leisure time also reported that they performed at least 1 hour per day of hard physical activity at work.
The survey used a probability sample of the U.S. civilian, noninstitutionalized population aged greater than or equal to 18 years5; 20,766 persons responded to the survey. Respondents were asked to identify the frequency and duration of their participation in 24 sports and conditioning activities during the 2 weeks preceding the survey, and to list the number of hours per day they spent doing hard physical work on the job.2
Leisure-time physical activities were scored by the intensity (i.e., metabolic equivalents [METs]), frequency, and duration of effort. METs for each leisure-time physical activity were based on the Compendium of Physical Activities.6 Respondents were categorized as (1) sedentary (no leisure-time activity), (2) irregularly active (not meeting public health recommendations), (3) moderately active (meeting the current public health recommendation),* or 4) vigorously active (meeting the fitness recommendation).† Hard physical activity at work was categorized as no hard labor, 1-4 hours per day, and greater than or equal to 5 hours per day. Prevalence of activity was calculated by age, sex, race/ethnicity, and education level using SUDAAN to adjust for the complex sampling frame.
Approximately one third of adults reported an adequate level of leisure-time physical activity: 31.5% were moderately active, and 4.6% were vigorously active. Men were more active than women at both the moderate and vigorous level. At the moderate level, whites were more active than Hispanics. The prevalence of both moderate and vigorous activity increased with education level and decreased with age.
More than half (56.4%) of adults reported doing no hard physical activity during the workday; however, 20% reported 1-4 hours per day, and 23.6% reported greater than or equal to 5 hours of hard occupational activity. Occupational activity was highest for persons who had less than 12 years of education, and was higher for blacks and Hispanics than whites. Occupational exertion decreased with increased education level and age.
The prevalence of hard occupational activity differed by level of leisure-time physical activity. Half (51.3%) of the respondents classified as sedentary in leisure time reported at least 1 hour of hard occupational activity per day. The prevalence of hard occupational activity was lower among persons classified as irregularly (42.0%), moderately (40.7%), or vigorously (36.8%) active during leisure time.
Physical Activity and Health Br, Div of Nutrition and Physical Activity, and Cardiovascular Health Br, Div of Adult and Community Health, National Center for Chronic Disease Prevention and Health Promotion, CDC.
The findings in this report indicate that during leisure time approximately two thirds (63.9%) of employed adults in the United States do not meet current recommendations for participation in moderate or vigorous physical activity. The NHIS findings were consistent with previous reports that indicate women, older adults, persons with less than 12 years of education, or members of racial/ethnic minorities are most likely to be inactive during leisure time.7 However, other opportunities exist for obtaining recommended amounts of physical activity, such as activities involved in commuting to and from work and those associated with certain occupations or maintaining a home.
Although the findings in this report suggest that adults may participate in physical activity at work, the frequency, intensity, and type of activity are not available from the NHIS data. Assessing activity patterns limited to leisure-time activity may underestimate the proportion of persons who obtain the recommended level of physical activity. Many persons from groups that are sedentary in their leisure time may be getting sufficient occupational physical activity to derive health benefits.
The findings in this report are subject to at least four limitations. First, estimates are based on self-reported activity and may be overestimates. Second, recall of the 24 types of leisure-time physical activity may have resulted in underreporting if seasonal or irregular activities were not performed during the 2-week recall period. Third, this study does not provide information on other sources of physical activity, such as transportation or housework, which may be disproportionately higher in certain population groups, such as women and racial/ethnic minorities. Finally, questions about occupational physical activity have not been asked since the 1990 NHIS, and the level of physical activity during work may have changed during the past decade.
CDC and the American College of Sports Medicine recommend that every U.S. adult accumulate 30 minutes or more of moderate-intensity physical activity on most, preferably all, days of the week.3 In 1990, only one third of employed adults met this recommendation or the recommendation for vigorous activity during leisure time. One of the national health objectives for 2000 was to reduce to no more than 15% the proportion of persons who engage in no leisure-time physical activity (objective 1.5).8
Systems that collect information on physical activity should be expanded to include additional activities. Because of the demonstrated health benefits of moderate-intensity physical activity, surveillance systems should be designed to assess activities such as occupational, childcare, and transportation for future monitoring of health-related physical activity.
Prevalence of Leisure-Time and Occupational Physical Activity Among Employed Adults—United States, 1990. JAMA. 2000;283(23):3064-3065. doi:10.1001/jama.283.23.3064-JWR0621-3-1