Physical Activity and Health Table 5-l. Sources of national and state-based data on physical activity* Mode of Physical Survey Abbreviated survey Population, Response Sample activity title title Sponsor administration Years aliF rate size measure+ Adults National NHIS Health Interview Survey Behavioral BRFSS Risk Factor Surveillance System National Household Center for interview Health Statistics (NOW, Centers for Disease Control and Prevention (CDC) National Telephone Center for interview Chronic Disease Prevention and Health Promotion (NCCDPHP), CDC Third NHANES III NCHS, Household National CDC interview Health and Nutrition Examination Survey Youths Youth Risk YRBS Behavior Survey NCCDPHP, Self- CDC administered in school National NHIS- NCHS, Household Health YRBS CDC administration Interview via au.diotape Survey- and self- Youth Risk completed Behavior answer sheets Survey 1985, 1990, 1991 I 986 1991 1992 1994 i 988-91 (Phase I) 1991, 1993, 1995 1992 us, ia+ years 83-88s 36,399 in 1985, 41,104 in 1990, 43,732 in 1991 25 states* and D.C., 1 a+ years 62-71% 48 states and D.C. 1 a+ years 7 1% Approx. 35,000- 50,000 96,343 49 states and D.C. 1 a+ years us, ia+ years 70% 82% 106,030 9,901 us gth- 12; grades 70-78% of 12,272 selected in 1991, (approxi- schools; 16,296 mately 86-90% of in 1993, 15-18 students 10,904 years) in 1995 us, 12-21 years 74% 10,645 F/I/W over past 2 weeks F/I/T/D over past month F/T over past month F/I/T/D over past week F/I/T over past week *Available at the time this report was compiled. `F = frequency; I = intensity; T = type; D = duration. *Alabama, Arizona, California, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Kentucky, Massachusetts, Minnesota, Missouri, Montana, New Mexico, New York. North Carolina, North Dakota, Ohio, Rhode Island, South Carolina, Tennessee, Utah, West Virginia, and Wisconsin. 176 avercstimate of the proportion of people who are regularly physically active. More clear-cut is the (;,tcgory of inactivity, which is considered to be the InoSt detrimental to health and is thus important to ,,,onitor as an indicator of need for intervention. \lcusurcs ofstretching and strength training are also d,.ri\ed, when possible, from the survey responses. The various surveys differ in the means by \i.hich they are conducted, in the wording of ques- tlons, in the time of year, in population sampling frames, in response rates, and in definitions of physical activity-all of which may cause differ- t`rlccs in the resulting physical activity estimates. 1 ~o~vever, even with these differences, the data from ,tlc several data collection systems reveal a number (,I consistencies in patterns and trends in self- reported leisure-time physical activity. Physical Activity among Adults in the United States Recent Patterns of Leisure-lime Physical Activity Physical Inactivity during Leisure Time i'hysical inactivity during leisure time is one of the c.;\sicst measures to define in population surveys. Ill:lctivity was conceptualized in the NHIS, BRFSS, .~ntL NHANES III as no reported leisure-time physi- .11 ;lctivity in the previous 2 to 4 weeks. Healthy I'c.c~plc 2000 objective 1.5 states that the proportion 01 Icisure-time physical inactivity among people .~gcd 6 years and older should be no more than 15 percent by the year 2000 (USDHHS 1990). The proportion of U.S. adults aged 18 years and ~~Iclt`r who were classified as physically inactive dur- 111% leisure time varied somewhat among the three : cccnt surveys (Table 5-2). In the 1991 NHIS, 24.3 ,Icrccnt reported no activity in the previous 2 weeks. 111 the 1992 BRFSS, 28.7 percent of adults reported [l(l activity during the previous month: In the 1988- 1991 NHANES III, in which for operational reasons l)Jrtlcipants tended to be surveyed in the North in lhc summer and the South in the winter, the preva- lc'nce of inactivity during the previous month was -0mcwhat lower-21.7 percent, Thus, despite minor differences, the surveys are s onsistent in finding that about one-fourth of U.S. Patterns and Trends in Physical Activity adults do not engage in any leisure-time physical activity, a proportion far from the 15 percent target of Healthy People 2000 objective 1.5. Also evident across the surveys is that more women than men are physically inactive (Figure 5-l). The ratio of physi- cal inactivity prevalence for women relative to that for men ranged from 1.2 to 1.7 across the three surveys. Findings for racial and ethnic groups, unad- justed for socioeconomic differences, were general11 in accord across the surveys (Table 5-2): whites had a lower prevalence of leisure-time inactivity than blacks, Hispanics, and persons categorizedas "other." Among the sex-specific racial and ethnic groups, white men were the least likely to be inactive (< 26 percent). White women had a prevalence of inactiv- ity (23.1-29.0 percent) similar to that among black men and lower than that among Hispanic men. At least one-third of black women and Hispanic women reported no physical activity in their leisure time. In all three surveys, the prevalence of physical inactivity was higher in older groups (Figure 5-l). Fewer than one in four adults aged 18-29 years engaged in no physical activity, whereas about one in three men and one in two women over 74 years of age were inactive (Table 5-2). For the most part, the prevalence of physical inactivity was greater among persons with lower levels of education and income. For example, there was twofold to threefold more inactivity from lowest to highest income categories: only 10.9 to 17.8 percent of participants with an annual family income of $50,000 or more reported no leisure-time physical activities, whereas 30.3 to 41.5 percent of those with an income less than $10,000 reported this. The prevalence of inactivity among adults tended to be lower in the north central and westernstates than in the northeastern and southern states (Table 5-2). Participants surveyed in the winter months reported being physically inactive substantially more often than did those surveyed during the summer months (Fig- ure S-2). In the 1994 BRFSS, state-specific prevalences of physical inactivity from 49 states and the District of Columbia ranged from 17.2 to 48.6 (Table 5-3). Regular, Sustained Physical Activity during Leisure Time Healthy People 2000 objective 1.3 proposes that at least 30 percent of people aged 6 years and older should engage regularly, preferably daily, in light to 177 Physical Activity and Health Table 5-2. Percentage of adults aged 18+ years reporting no participation in leisure-time physical activity, by various demographic characteristics, National Health Interview Survey (NHIS), Third National Health and Nutrition Examination Survey (NHANES Ill), and Behavioral Risk Factor Surveillance System (BRFSS), United States Demographic group 1991 NHIS' 1988-l 991 NHANES Ill* 1992 BRFSS*+ Overall Sex Males Females Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanics Males Females Other Males Females Age (years) Males 18-29 30-44 45-64 65-74 75+ Females 18-29 30-44 45-64 65-74 75+ Education < 12 yrs 12 yrs Some college (13-l 5 yrs) College (16+ yrs) lncomeq < $10,000 $10,000-19,999 $20,000-34,999 $35,000-49,999 $50,000+ Geographic region Northeast North Central South West 24.3 (23.2, 25.3)* 21.7 (19.0, 24.5) 21.4 (20.2, 22.6) 26.9 (25.8, 28.0) 15.8 (12.4, 19.2) 27.1 (23.0, 31.3) 22.5 (21.4, 23.7) 20.3 (19.0, 21.6) 24.6 (23.4, 25.8) 28.4 (26.4, 30.4) 22.5 (20.0, 25.0) 33.2 (30.8, 35.6) 33.6 (31.0, 36.3) 29.6 (26.0, 33.2) 37.4 (34.1, 40.8) 26.7 (23.4, 30.0) 22.8 (18.2, 27.3) 30.8 (27.0, 34.7) 17.6 (15.8, 19.4) 21.1 (19.8, 22.5) 23.9 (22.1, 25.7) 23.0 (20.4, 25.6) 27.1 (23.8, 30.4) 25.0 (23.4, 26.6) 25.2 (23.8, 26.61 27.4 (25.9, 28.91 27.8 (25.7, 29.9) 37.9 (35.3, 40.6) 37.1 (35.3, 38.9) 25.9 (24.7, 27.1) 19.0 (17.8, 20.2) 14.2 (13.1, 15.3) 30.3 (28.4, 32.2) 30.2 (28.5, 32.0) 24.3 (22.9, 25.7) 19.5 (18.1, 20.9) 14.4 (13.2, 15.6) 25.9 (24.5, 27.3) 20.8 (18.7. 22.91 27.0 (25.2, 28.8) 22.5 (19.5, 25.5) 18.2 (15.6, 20.8) 12.9 (9.6, 16.1) 23.1 (19.0, 27.11 30.4 (25.6, 35.3) 20.6 (14.5, 26.8) 38.1 (30.9, 45.2) 36.0 (32.5, 39.51 29.1 (24.3, 33.9) 43.8 (38.5, 49.1) II 12.5 (9.0, 16.0) 14.5 (10.9, 18.1) 16.9 (13.0, 20.8) 17.5 (12.2, 22.8) 34.5 (28.0, 41 .l) 17.4 (13.4, 21.4) 24.9 (20.6, 29.3) 29.4 (24.6, 34.2) 32.5 (25.9, 39.2) 54.3 (47.9, 60.6) 34.5 (31.2, 37.8) 20.8 (17.4, 24.3) 15.7 (11.4, 19.9) 11.1 (6.9, 15.4) 34.5 (30.3, 38.7) 28.5 (24.5, 32.6) 18.7 (14.8, 22.6) 15.9 (10.9, 20.9) 10.9 (6.7, 15.1) 21.6 (8.5, 34.6) 16.7 (7.6, 25.8) 24.8 (18.4, 31.1) 22.6 114.8, 30.5) 28.7 (28.3, 29.11 26.5 (25.9, 27.1) 30.7 (30.1, 31.3) 26.8 (26.4, 27.2) 25.3 (24.7, 25.91 28.2 (27.6, 28.8) 38.5 f36.9, 40.1) 33.1 (30.9, 35.3) 42.7 (40.7, 44.7) 34.8 (32.8, 36.8) 30.2 (27.3, 33.1) 39.0 (36.5, 41.5) 31.4 (28.9, 33.9) 27.6 (24.1, 31.11 35.8 (32.3, 39.3) 18.9 (17.7, 20.1) 25.0 (24.0, 26.0) 32.0 (30.8, 33.2) 33.2 (31.2, 35.2) 38.2 (35.3, 41.1) 25.4 (24.2, 26.6) 26.9 (25.9, 27.9) 32.1 (30.9, 33.3) 36.6 (34.8, 38.4) 50.5 (48.5, 52.5) 46.5 (45.3, 47.7) 32.8 (32.1, 33.6) 22.6 (21.9, 23.4) 17.8 (17.0, 18.5) 41.5 (40.1, 42.9) 34.6 (33.6, 35.6) 26.9 (26.1, 27.7) 23.0 (22.0, 24.0) 17.7 (16.9, 18.5) 29.5 (28.5, 30.5) 28.6 (27.8, 29.4) 32.4 131.6, 33.2) 22.0 (21.0, 23.0) Sources: Centers for Dtsease Control and Preventton, National Center ior Health Statistics, NHIS, public use data tapes, 1991; Centers for Disease Control and Prevention, Nattonal Center for Health Stattstics, NHANES, public use data tapes, 1988-1991 ; Centers for Disease Control and Preventton, National Center for Chronic Disease Prevention and Health Promotion, BRFSS, 1992. o NHlS asked about the prior 2 weeks; BRFSS asked about the prror month. `Based on data from 48 states and the Distrtct of Columbia `95% confidence intervals. q Hispanic reflects Mexican-Americans in NHANES III. "Estimates unreliable. IAnnual income per family (NHIS) or household (BRFSS). 178 Patterns and Trends in Physical Activity Figure 5-1. Percentage of adults aged 18+ years reporting no participation in leisure-time physical activity by sex and age 60 r cl 75+ 0 65-74 O 45-64 I 3044 g 18-29 2 E 30 a 20 10 0 NHANES Women 1988-l 991 BRFSS Men BRFSS Women 1992 1992 NHIS Men NHIS Women NHANES Men 1991 1991 1988-l 99 1 Survey-sex group Figure 5-2. Percentage of adults aged 18+ years reporting no participation in leisure-time physical activity by month 40 30 E 8 20 z a 10 0 r 1992 BRFSS December January December January Monthly trend within survey 179 1991 NHIS Physical Activity and Health Table 5-3. Percentage of adults aged 18+ years reporting participation in no activity; regular, sustained activity; and regular, vigorous activity, by state,* Behavioral Risk Factor Surveillance System (BRFSS), 1994, United States Overall Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware D.C. Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi No activity 29.4 (29.0, 29.8)+ 45.9 (43.2,48.6) 22.8 (19.9, 25.7) 23.7 (21.2,26.2) 35.1 (32.6,37.6) 21.8 (20.2, 23.4) 17.2 (15.0, 19.4) 22.1 (19.9, 24.3) 36.4 (34.0,38.8) 48.6 (45.3,51.9) 28.0 (26.2,29.8) 33.0 (30.6,35.4) 20.8 (18.6, 23.0) 21.9 (19.7, 24.1) 33.5 (31.1,35.9) 29.7 (27.7, 31.7) 33.2 (31.2,35.2) 34.5 (31.8, 37.2) 45.9 (43.5,48.3) 33.5 (30.8, 36.2) 40.7 (37.8,43.6) 30.5 (28.9, 32.1) 24.0 (21.6,26.4) 23.1 (21.1, 25.1) 21.8 (20.4,23.2) 38.5 (35.6,41.4) Regular, sustained activity 19.7 (19.3,20.1) 17.1 (14.9,19.3) 28.3 (24.8,31.8) 17.8 (15.4,20.2) 17.2 (15.0,19.4) 21.9 (20.3,23.5) 26.5 (24.1,28.9) 26.9 (24.5,29.3) 17.7 (15.7,19.7) 11.6 (9.4, 13.8) 23.8 (22.2,25.4) 18.0 (16.0,20.0) 25.5 (23.3,27.7) 26.3 (23.8,28.8) 15.7 (13.9,17.5) 18.8 (17.0,20.6) 15.9 (14.3,17.5) 16.8 (14.6,19.0) 13.2 (11.6,14.8) 16.8 (14.8,18.8) 13.0 (11 .o, 15.0) 17.6 (16.2,19.0) 23.2 (21.0,25.4) 21.8 (19.8,23.8) 20.1 (18.7,21.5) 14.0 (12.0, 16.0) moderate physical activity requiring sustained, rhythmic muscular movements for at least 30 min- utes per day WSDHHS 1990). Regular, sustained activity derived from the NHIS and the BRFSS was defined as any type or intensity of activity that occurs 5 times or more per week and 30 minutes or more per occasion (see Appendix B >. This defini- tion approximates the activity goal of the healtlty People 2000 objective but includes vigor'ous activity of at least 30 minutes duration as well. Comparable information was unavailable in the NHANES III. The percentage of U.S. adults meeting this defini- tion of regular, sustained activity during leisure time was about 22 percent in the two surveys (23.5 in the NHlS and 20.1 in the BRFSS; see 14.0 (13.6, 14.4) 11.2 (9.4,13.0) 15.1 (12.4,17.8) 17.9 (15.4,20.4) 10.7 (9.lIl2.3) 15.7(14.5,16.9) 15.9(14.1,17.7) 16.9(14.9,18.9) 14.1 (12.5,15.7) 8.7 (6.9,10.5) 20.0 (18.6,21.4) 13.5 (11.9,lS.l) 18.3(16.3,20.3) 15.7 (13.7,17.7) 14.6 (12.8,16.4) 13.0 (11.4,14.6) 13.3 (11.9,14.7) 13.9 (11.9,15.9) 11.3 (9.9,12.7) 11.3 (9.5,13.1) 11.3 (9.5,13.1) 14.5 (13.3,15.7) 17.4(15.4,19.4) 14.5(12.9,16.1) 15.4(14.2,16.6) 9.8 (8.2, 11.4) Regular, vigorous activity Table 5-4)-S percentage points lower than the Healthy People 2000 target. The prevalence of regular, sustained activity was somewhat higher among men than women; male:female ratios were 1.1:1.3. The two surveys found no consistent association between racial/ ethnic groups and participation in regular, sustained activity. The prevalence of regular, sustained activity tended to be higher among 1% through 29-year-olds than among other age groups, and it was lowest (5 15 percent) among women aged 75 years and older. Education and income levels were associated posi- tively with regular, sustained activity. For example, adults with a college education had an approxi- mately 50 percent higher prevalence of regular, sus- tained activity than those with fewer than 12 years of 180 Patterns and Trends in Physical Activity Table 5-3. Continued /GGZGi Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming No activity 32.0 (29.3, 34.7) 21 .O (18.6, 23.4) 24.3 (22.1,26.5) 21.7 (19.5,23.9) 25.8 (23.3, 28.3) 30.9 (28.2, 33.6) 19.8 (17.3, 22.3) 37.1 (34.7,39.5) 42.8 (40.3,45.3) 32.0 (29.6,34.4) 38.0 (35.1,40.9) 30.4 (28.0,32.8) 20.8 (19.2, 22.4) 26.5 (24.9, 28.1) 31.4 (29.2,33.6) 30.8 (28.4,33.2) 39.7 (37.7,41.7) 27.8 (25.1,30.5) 21.0 (18.8,23.2) 23.3 (21.5, 25.1) 23.0 (20.6,25.4) 18.2 (16.8, 19.6) 45.3 (43.1,47.5) 25.9 (23.2, 28.6) 20.9 (18.4, 23.4) Regular, sustained activity 18.0 (15.8,20.2) 21.8 (19.3,24.3) 16.7 (14.7,18.7) 25.3 (22.9,27.7) 21.2 (19.0,23.4) 20.7 (18.3,23.1) 25.5 (22.6,28.4) 14.8 (13.2,16.4) 12.7 (11.1,14.3) 20.2 (18.0,22.4) 15.9 (13.7,18.1) 23.0 (20.8,25.2) 27.3 (25.3,29.3) 21.2 (19.6,22.8) 15.1 (13.3, 16.9) 19.4 (17.4,21.4) 15.0 (13.6,16.4) 20.7 (18.2,23.2) 21.6 (19.4,23.8) 25.7 (23.7,27.7) 24.6 (22.2,27.0) 25.7 (24.1,27.3) 14.3 (12.7,15.9) 22.7 (20.2,25.2) 27.9 (24.8,31.0) Regular, vigorous activity 10.8 (9.0,12.6) 15.0(12.6,17.4) 14.7(12.9,16.5) 14.1 (12.3,15.9) 17.0(14.8,19.2) 11.6 (9.8,13.4) 18.4 (16.0,20.8) 10.6 (9.2,12.0) 9.3 (7.9,10.7) 13.9 (12.1,15.7) 12.4 (10.4,14.4) 11.1 (9.5,12.7) 18.7(17.1,20.3) 14.5(13.3,15.7) 11.9(10.3,13.5) 11.9(10.3,13.5) 12.7(11.3,14.1) 13.0 (11 .o, 15.0) 14.3(12.5,16.1) 18.4(16.6,20.2) 14.6(12.8, 16.4) 16.8(15.4,18.2) 9.8 (8.4, 11.2) 12.7 (10.7, 14.7) 16.3(13.9,18.7) Source: Centers for Disease Control and Preventjon, National Center for Chronic Disease Prevention and Health Promotion, BRFSS, 1994 *Includes 49 states and the Dlstrlct of Columbia. Data for Rhode Island were unavailable `9% confidence Intervals. education. Among the regions of the United States, the West tended to have the highest prevalence of adults participating in regular, sustained activity (Table 5-4). Regular, sustained activity, which com- prises manyoutdooractivities, was most prevalent in the summer. In the 1994 BRFSS, state-specific prevalences of regular, sustained activity ranged from 11.6 to 28.3 (Table 5-3). Regular, Vigorous Physical Activity during 1 eisore Time People who exercise both regularly and vigorously would be expected to improve cardiovascular fitness the most. The NHIS and the BRFSS defined regular, vigorous physical activity as rhythmic contraction of large muscle groups, performed at 50 percent or more of estimated age- and sex-specific maximum cardio- respiratory capacity, 3 times per week or more for at least 20 minutes per occasion (see Appendix B). The prevalence of regular, vigorous leisure-time activ- ity reported by U.S. adults was about 15 percent (16.4 percent in the 1991 NHIS and 14.2 percent in the 1992 BRFSS; see Table 5-5). This prevalence is lower than the goal stated in Healthy People 2000 objective 1.4, which is to have at least 20 percent of people aged 18 years and older engage in vigorous physical activity at 50 percent or more of individual cardiorespiratory capacity 3 days or more per week for 20 minutes or more per occasion (USDHHS 1990). 181 Physical Activity and Health Table 5-4. percentage of adults aged 1 B+ Years reporting participation in regular, sustained physical activity (5+ times per week for 30+ minutes per occasion), bY various demographic characteristics, National Health Interview Survey (NHIS) and Behavioral Risk Factor Surveillance System (BRFSS), United States 1991 NHIS* 1992 BRFSS*+ 23.5 (22.9, 24.1)' 20.1 (19.7, 20.5) Demographic group Overall 21.5 (20.9, 22.1) 18.9 (18.4, 19.3) Sex Males Females Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females Other Males Females Age (years) Males 18-29 30-44 45-64 65-74 75+ Females 18-29 30-44 45-64 65-74 75+ Education < 12 yrs 12 yrs SOme college (13-l 5 yrs) College (16+ yrs) Income* < $10,000 $1 o,ooo-19,999 .$20,000-34,999 $35,00049,999 950,000+ Geographic region Northeast North Central south 18.1 (17.0, 19.2) 21.9 (21.0, 22.7) 26.8 (25.7, 28.0) 28.5 (27.3, 29.6) 23.6 (21.8, 25.5) 20.4 (19.3, 21.4) 23.2 (22.2, 24.2) 23.9 (22.7, 25.1) 28.0 (26.8, 29.2) 17.6 (16.6, 18.6) 18.7 (17.9, 19.5) 20.3 (19.5, 21.1) 20.9 (19.9, 21.9) 23.5 (22.5, 24.5) West 26.1 (24.b, ~1.3~ 23.9 (22.8, 25.0) 24.2 (22.7, 25.6) 21.1 (19.9, 22.2) -. , -7 I-, 20.2 (19.; !, 21.2) 18.2 (17.' 4, 19.0) lg.0 (18.4, 19.6) 24.0 (23.0, 25.c -- 3) - sources: Centers for Disease Control and Prevention, National Center for Health Statistics, NH% public use data tapes, Disease Control and Prevention, National center for Chronic Disease Prevention and Health PromotIon, BRFSS, lgg2. 26.6 (25.7, 27.5) 20.7 (19.9, 21.5) 24.0 (23.2, 24.7) 26.7 (25.7, 27.6) 21.5 (20.6, 22.4) 22.9 (21.4, 24.4) 28.9 (26.6, 31.3) 18.0 (16.2, 19.8) 20.0 (18.1, 21.9) 23.7 (20.6, 26.7) 16.5 (14.3, 18.7) 23.4 (20.5, 26.2) 25.5 (21.0, 30.0) 21.1 (17.7, 24.6) 32.0 (30.2, 33.7) 24.1 (22.8, 25.3) 24.2 (22.8, 25.6) 29.2 (27.0, 31.4) 24.6 (21.8, 27.4) 23.2 (21.6, 24.8) 20.4 (19.4, 21.4) 20.6 (19.4, 21.8) 21.3 (19.5, 23.0) 13.8 (12.2, 15.4) 20.8 (20.4, 21.2) 21.9 (21.3, 22.5) 19.8 (19.2, 20.4) 15.2 (14.0, 16.4) 18.5 (16.5, 20.5) 12.6 (11.4, 13.8) 20.1 (18.5, 21.7) 21.4 (18.9, 23.9) 18.9 (16.7, 21.1) 17.3 (15.1, 19.5) lg.7 (16.6, 22.8) 14.5 (12.0, 17.0) 26.8 (25.4, 28.2) 17.4 (16.6, 18.2) 18.9 (17.7, 20.1) 26.8 (24.8, 28.8) 23.2 (20.5, 25.9) lg.9 (18.7, 21.1) 18.5 (17.7, 19.3) 19.4 (18.4, 20.4) 19.0 (17.6, 20.4) 15.0 (13.4, 16.6) 15.6 (14.6, 16.6) 17.8 (17.2, 18.4) 22.7 (21.9, 23.5) 23.5 (22.7, 24.3) *Based on data from 48 states and the District of Columbia. `~~1s asked about the prior 2 weeks; BRFSS asked about the Prior month. *gS% confidence intervals. ~~~~~~~ Income per family (NHIS) or household (BRFSS). 182 1 ggl ; Centers for Patterns and Trends in Physical Activity Table 5-5. Percentage of adults aged 18+ years participating in regular, vigorous physical activity (3+ times per week for 20+ minutes per occasion at 5O+ percent of estimated age- and sex-specific maximum cardiorespiratory capacity), by various demographic characteristics, National Health Interview Survey (NHIS) and Behavioral Risk Factor Surveillance System (BRFSS), United States Demographic group Overall Sex Males Females Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females Other Males Females Age (years) Males 18-29 30-44 45-64 65-74 75+ Females 18-29 30-44 45-64 65-74 75-t Education < 12 yrs 12 yrs Some college (13-l 5 yrs) College (1 6+ yrs) Income5 < $10,000 $10.000-19,999 $20,000-34,999 $35,000-49,999 $50,000+ Geographic region Northeast North Central South West 1991 NHlS* 16.4 (15.9, 16.9)* 18.1 (17.4, 18.8) 12.9 (12.5, 13.3) 14.9 (14.3, 15.5) 15.8 (15.4, 16.2) 17.2 (16.6, 17.7) 15.3 (14.9, 15.7) 18.6 (17.9, 19.3) 13.3 (12.7, 13.9) 15.9 (15.2, 16.6) 17.1 (16.5, 17.7) 12.9 (11.7, 14.0) 9.4 (&6, 10.2) 16.0 (13.9, 18.0) 9.5 (8.1, 10.9) 10.4 (9.0, 1 1.7) 9.4 (8.4, 10.4) 13.6 (11.9, 15.2) 11.9 (10.5, 13.3) 15.6 (12.9, 18.3) 12.4 (10.2, 14.6) 11.7 (9.9, 13.4) 11.4 (9.8, 13.0) 16.8 (14.5, 19.1) 11.8 (10.0, 13.6) 18.8 (15.2, 22.3) 11.5 (9.0, 14.0) 14.8 (11.9, 17.8) 12.2 (10.0, 14.4) 19.7 (18.3, 21.1) 8.0 (7.2, 8.83 13.7 (12.8, 14.6) 11.1 (10.3, 11.9) 14.9 (13.7, 16.1) 16.3 (15.3, 17.3) 27.3 (25.2, 29.5) 20.6 (18.8, 22.4) 38.3 (35.2, 41.5) 20.6 (18.1, 23.1) 16.0 (14.7, 17.3) 11.4 (10.6, 12.2) 13.3 (12.4, 14.1) 18.0 (17.2, 18.8) 12.1 (11.1, 13.0) 17.7 (16.7, 18.7) 18.5 (16.9, 20.1) 16.5 (15.1, 17.9) 22.6 (20.5, 24.7) 12.8 (11.4, 14.2) 11.9 (11.1, 12.8) 8.2 (7.4, 9.0) 13.6 (13.0, 14.3) 11.5 (10.9, 12.1) 18.9 (17.9, 19.9) 14.9 (14.3, 15.5) 23.5 (22.4, 24.6) 21.9 (21.1, 22.7) 15.5 (14.1, 17.0) 9.0 (8.2, 9.8) 14.4 (13.5, 15.4) 10.8 (10.2, 1 1.4) 15.5 (14.6, 16.4) 14.2 (13.6, 14.8) 16.0 (14.9, 17.0) 16.3 (15.5, 17.1) 21.5 (20.4, 22.6) 20.5 (19.5, 21.5) 16.1 (15.2, 16.9) 13.8 (13.0, 14.6) 76.5 (15.5, 17.5) 13.7 (13.1, 14.3) 14.7 (13.9, 15.5) 13.8 (13.2, 14.4) 19.2 (17.9, 20.5) 16.8 (16.0. 17.6) 1992 BRFSS*+ 14.4 (14.0, 14.8) Sources: Centers for Disease Control and Prevention, National Center for Health Statistics, NHIS, 1991; Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, BRFSS, 1992. `NHIS asked about the prior 2 weeks; BRFSS asked about the prior month `Based on data from 48 states and the District of Columbia. `95% confidence intervals. `Annual income per family (NHIS) or household (BRFSS). 183 Physical Activity and Health The proportion performing regular, vigorous ac- tivity was 3 percentage points higher among men than women in the NHIS, but it was 3 percentage points higher among women than men in the BRFSS. This difference between sexes in the surveys may be related to the BRFSS's use of a correction procedure (based on speeds of activities like walking, jogging, and swim- ming) to create intensity coding (Appendix B; Caspersen and Powell [unpublished technical mono- graph] 1986; Caspersen and Merritt 1995). Regular, vigorous activity tended to be more prevalent among whites than among blacks and Hispanics (Table 5-5). These racial and ethnic patterns were somewhat more striking among women than among men. The relationship between regular, vigorous physi- cal activity and age varied somewhat between the two surveys. In the NHIS, the prevalence of regular, vigorous activity was higher for men and women aged 18-29 years than for those aged 30-64 years, but it was highest among men and women aged 65 years and older. Among men participating in the BRFSS, regular, vigorous activity increased with age from those 18-29 years old to those 2 65 years old. Amongwomen participating in the BRFSS, the preva- lence of regular, vigorous activity was higher for those aged 30-74 years than for those aged 18-29 years and L 75 years. The finding of generally lower prevalences of regular, vigorous activity among younger than older adults (Table 5-5) may seem .unexpected. It is ex- plained partly by both the greater leisure time of older adults and the use of an age-related relative intensity classification (Caspersen, Pollard, Pratt 1987; Stephens and Caspersen 1994; Caspersen and Merritt 1995). Because cardiorespiratory capacity declines with age, activities that would be moder- ately intense for young adults, such as walking, become more vigorous for older people. If the two surveys had instead used an absolute intensity clas- sification, the estimated prevalence of people.engag- ing in regular, vigorous physical activity would have fallen dramatically with age. (This age-related drop in activities of high absolute intensity is shown in Table 5-6 and described in the next section.) Like- wise, the male:female ratio ofvigorousactivitypreva- lence in Table 5-5 would rise if an absolute intensity classification were used, because women have a lower average cardiorespiratory capacity than men. In both surveys, the proportion of adults report- ing regular, vigorous activity was higher in each successive educational category (Table 5-S). Adults who had college degrees reported regular, vigorous activity approximately two to three times more often than those who had not completed high school. In the NHIS, a similar positive association was seen between income and regular, vigorous physical ac- tivity. In the BRFSS, the prevalence of regular, vigor- ous physical activity was highest at the highest income level. The prevalence of regular, vigorous physical activity was not consistently related to em- ployment status or marital status in the two surveys. It was higher in the West than in other regions of the United States and in warmer than in colder months. In the 1994 BRFSS, state-specific prevalences of regular, vigorous activity ranged from 6.7 to 16.9 (Table 5-3). Participation in Specific Physical Activities NHIS participants reported specific activities in the previous 2 weeks (Table 5-6). By far, walking was the most commonly reported leisure-time physical ac- tivity, followed by gardening or yard work, stretch- ingexercises, bicycling, strengthening exercises, stair climbing, jogging or running, aerobics or aerobic dancing, and swimming. Because these percentages are based on all participants in the year-round NHIS, they underestimate the overall prevalence of partici- pation in seasonal activities, such as skiing. Substantial differences exist between the sexes for many activities. Gardening or yard work, strength- ening exercises, jogging or running, and vigorous or contact sports were more commonly reported by men than women. Women reported walking and aerobics or aerobic dancing more often than men and reported participation in stretching exercises, bicy- cling, stair climbing, and swimming about as often as men. Participation in most activities, especially weight lifting and vigorous or contact sports, declined sub- stantially with age (Table 5-6). The prevalence of walking, gardening or yard work, and golf tended to remain stable or increase with age. Among adults aged 65 years and older, walking (> 40 percent prevalence) and gardening or yard work (> 20 per- cent prevalence) were by far the most popular activities. 184 Patterns and Trends in Physical Activity Table 5-6. Percentage of adults aged 18+ years reporting participation in selected common physical activities in the prior 2 weeks, by sex and age, National Health Interview Survey (NHIS), United States, 1991 Activity category \vcllking for exercise Gardening or vard work Stretching exercises l\/erp,ht lifting or other exercise to increase mscle strength ~,,eji~ng or running .\probics or aerobic dance titling a bicycle or exercise bike \ttcar skiing lLi4dbJII ~iJll~\hiII h x ccLr ~1~~l1,`~ll Jthcr sports All Males Females ages and 18-29 30-44 45-64 65-74 75+ All 18-29 30-44 45-64 65-74 75+ All sexes 32.8 37.6 43.3 50.1 22.2 36.0 39.8 42.6 32.1 27.2 20.0 15.5 33.6 21.2 12.2 6.4 22.6 14.1 7.7 1.4 3.4 3.3 2.1 1.6 18.7 18.5 14.0 10.8 10.5 11.4 9.6 6.0 10.1 7.6 5.3 3.1 5.7 3.3 2.9 1.1 7.0 5.2 3.0 2.8 7.9 8.6 7.9 9.7 11.0 6.9 1.8 0.4 5.2 2.8 1.5 115 1.0 0.4 0.1 0.5 0.5 1.5 0.7 0.3 24.2 10.5 2.4 6.8 3.0 1 .l 3.3 1.4 0.3 7.6 1.8 0.4 8.6 7.9 6.0 0.3 0.1 0.2 - 0.1 0.2 0.1 0.2 6.2 47.1 39.4 38.4 34.2 15.7 25.0 4.7 20.0 0.5 12.8 1.0 2.8 8.4 16.2 4.0 9.9 1.4 6.9 0.4 3.5 1.6 4.7 4.9 8.2 - 5.8 - 2.7 - 0.9 0.4 0.4 - 0.7 0.1 10.5 0.2 3.1 - 1.4 - 2.7 5.2 7.3 47.4 49.1 49.4 50.1 40.5 48.3 44.1 15.4 28.6 29.6 28.2 21.5 25.1 29.4 32.5 27.7 21.4 21.9 17.9 26.0 25.5 14.5 10.6 5.1 2.8 1.1 8.8 14.1 11.6 6.5 2.5 0.8 0.4 5.7 9.1 19.3 12.3 6.6 4.2 1 .6 11.1 7.1 17.4 16.9 12.6 11.4 6.0 14.6 15.4 14.6 12.8 10.3 7.3 5.6 11.6 10.8 8.0 7.5 4.6 4.2 3.1 2.4 1.3 0.6 4.8 4.2 2.8 2.5 1.4 1.7 2.2 3.3 3.2 1.7 0.3 0.2 6.2 6.5 2.0 2.7 3.6 4.1 1.8 4.9 1.4 3.5 1.0 0.4 0.4 0.1 0.9 0.6 0.3 0.0 0.3 0.4 0.6 0.2 0.7 0.5 0.1 0.0 3.1 1.7 0.4 - 4.4 1.9 0.5 0.0 0.9 0.4 0.1 - 0.7 0.4 0.0 - 4.5 4.5 3.6 4.3 0.5 1.6 0.5 0.7 0.4 0.4 0.4 0.5 1.5 5.8 1.8 2.5 0.4 0.9 0.3 1.5 4.1 5.7 \olc>: 0.0 = quantity less than 0.05 but greater than zero; - = quantity is equal to zero. ")UR c': Centers for Disease Control and Prevention, National Center for Health Statistics, NHIS, 1991 185 Physical Activity and Health Healthy People 2000 objective 1.6 recommends that at least 40 percent of people aged 6 years and older should regularly perform physical activities that enhance and maintain muscular strength, mus- cular endurance, and flexibility (USDHHS 1990). National surveys have not quantified all these activi- ties but have inquired about specific sentinel activi- ties, such as weight lifting and stretching. In the 1991 NHIS, 14.1 percent of adults reported "weight lifting and other exercises to increase muscle strength" in the previous 2 weeks (Table 5-7). Participation in strengthening activities was more than twice as preva- lent among men than women. Black men tended to have the highest participation (26.2 percent) and black women the lowest (6.9 percent). Participation was much higher among younger than older adults, among the more affluent than the less affluent, and in the West than in other regions of the United States. Of special concern, given the promising evi- dence that strengthening exercises provide substan- tial benefit to the elderly (see Chapter 4), is the low prevalence of strengthening activities among those aged 65 or older (I 6.4 percent in men and I 2.8 percent in women; see Table 5-7). Adult participation in stretching activity over the previous 2 weeks was 25.5 percent in the NHIS (Table 5-7). Stretching participation declined with age and tended to be associated positively with levels of education and income and to be lower in the South than in other regions of the United States. Leisure-lime Physical Activity among Adults with Disabilities Although little information is available on physical activity patterns among people with disabilities, one recent analysis was based on the special NHIS Health Promotion and Disease Prevention Supplement from 1991. Heath and colleagues (1995) compared physi- cal activity patterns among people with disabilities (i.e., activity limitations due to a chronic health problem or impairment) to those among people without disabilities. People with disabilities were less likely to report engaging in regular moderate physical activity (27.2 percent) than were people without disabilities (37.4 percent). People with dis- abilities were also less likely to report engaging in regularvigorousphysicalactivity (9.6percentvs. 14.2 percent). Correspondingly, people with disabilities were more likely to report being inactive (32 percent vs. 27 percent). Trends in Leisure-Time Physical Activity Until the 20th century, people performed most physical activity as part of their occupations or in subsistence activities. In Western populations, occupation-related physical demands have declined, and the availability of leisure time has grown. It is generally believed that over the past 30 years, as both the popularity of sports and public awareness of the role of physical activity in maintaining health have increased, physical activity performed during leisure time has increased (Stephens 1987; Jacobs et al. 1991). Stephens concluded that the increase was greater among women than men and among older than younger adults and that the rate of increase probably was more pronounced in the 1970s than between 1980 and 1985 (Stephens 1987). However, no systematic data were collected on physical activity among U.S. adults until the 1980s. Even now, few national data are available on consistently measured trends in physical activity. The NHIS has data from 1985,1990, and 1991, and the BRFSS has consistent data from the same 25 states and the District of Columbia for each year between 1986 and 1992 and for 1994. According to the NHIS, participation in leisure-time physical ac- tivity among adults changed very little between the mid-1980s and the early 1990s (Table 5-8 and Figure 5-3). Similarly, in the BRFSS (Table 5-8 and Figure 5-4), little improvement was evident from 1986 through 1994. Physical Activity among Adolescents and Young Adults in the United States The most recent U.S. data on the prevalence of physical activity among young people are from the 1992 household-based NHIS-YRBS, which sampled all young people aged 12-21 years, and the 1995 school-based YRBS, which included students in grades 9-12. Variations in estimates between the NHIS-YRBS and the YRBS may be due not only to the distinct populations represented in each survey but also to the time of year each survey was conducted, the mode of administration, the specific wording of 186 Demographic group Overall Sex Males Females Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females Other Males Females Age (years) Males 18-29 30-44 45-64 65-74 75+ Females 18-29 30-44 45-64 65-74 75+ Education < 12 yrs 7.4 (6.6, 8.1) 14.7 (13.5, 15.8) 12 yrs 12.3 (11.7, 13.0) 22.6 (21.7, 23.6) Some college (I 3-l 5 yrs) 18.3 (17.3, 19.2) 31.3 (29.9, 32.7) College (16+ yrs) 19.6 (18.6, 20.6) 35.4 (34.0, 36.9) income* < s 10,000 12.9 (11.4, 14.4) 23.4 (21.7, 25.1) B 10,000-$19,999 10.7 (9.8, 11.6) 21.0 (19.7, 22.3) $20,000-834,999 14.3 (13.4, 15.1) 25.6 (24.4, 26.9) $35,000-849,999 15.3 (14.3, 16.3) 28.9 (27.4, 30.4) $50,000+ 19.1 (18.1, 20.2) 33.5 (32.1, 34.9) Geographic region Northeast 13.8 (12.9, 14.8) 24.9 (23.6, 26.2) North Central 14.5 (13.6, 15.3) 28.5 (26.5, 30.6) South 12.4 (11 .6, 13.3) 20.8 (19.2, 22.4) West 16.5 (15.4, 17.7) 29.9 (28.1, 31.7) Source: Centers tar Disease Control and PreventIon, National Center for Health Statistics, NHIS, 1991. Strengthening activities Stretching exercises 14.1 (13.6, 14.6)+ 25.5 (24.7, 26.4) 20.0 (19.2, 20.7) 25.0 (24.0, 26.1) 8.8 (8.3, 9.2) 26.0 (25.1, 27.0) 13.7 (13.2, 14.2) 25.9 (24.9, 26.8) 18.8 (18.0, 19.6) 24.9 (23.8, 26.0) 9.0 (8.5, 9.6) 26.7 (25.7, 27.8) 15.5 (14.2, 16.9) 24.2 (22.5, 26.0) 26.2 (23.7, 28.7) 24.7 (22.1, 27.3) 6.9 (5.8, 8.0) 23.9 (21.7: 26.0) 15.8 (13.9, 17.6) 22.4 (19.9, 24.9) 23.4 (20.3, 26.5) 23.6 (20.4, 26.7) 8.6 (7.0, 10.3) 21.3 (18.3, 24.3) 14.9 (12.3, f7.5) 30.0 (26.2, 33.8) 20.3 (16.0, 24.7) 31.4 (26.0, 36.8) 9.2 (6.6, 11.7) 28.5 (24.3, 32.7) 33.6 (31.7, 35.5) 32.1 (30.1, 34.2) 21.2 (20.1, 22.3) 27.2 (25.8, 28.6) 12.2 (11.1, 13.4) 20.0 (18.6, 21.5) 6.4 (5.1, 7.7) 15.5 (13.4, 17.6) 4.7 (3.1, 6.3) 15.7 (13.2, 18.3) 14.5 (13.3, 15.6) 32.5 (30.7, 34.2) 10.6 (9.9, 11.4) 27.7 (26.3, 29.0) 5.1 (4.5, 5.8) 21.4 (20.1, 22.8) 2.8 (2.0, 3.7) 21.9 (20.0, 23.8) 1.1 (0.7, 1.6) 17.9 (16.0, 19.9) Patterns and Trends in Physical Activity Table 5-7. Percentage of adults aged 18+ years reporting participation in any strengthening activities* or stretching exercises in the prior 2 weeks, by various demographic characteristics, National Health Interview Survey (NHIS), United States, 1991 *Strengthening actwities include weight lifting and other exercises to increase muscle strength. `95% confidence intervals. *Annual income per family. 187 Physical Activity and Health Table 5-8. Trends in the percentage of adults aged 18+ years reporting participation in no activity; regular, sustained activity; and regular, vigorous activity, by sex, National Health Interview Survey (NHlS) and Behavioral Risk Factor Surveillance System (BRFSS), United States, from 1985-I 994 1985,1990,1991 NHIS 1986-l 994 BRFSS' Males Females Total Males Females Total No activity 1985 19.9 (18.8, 20.9)+ 26.3 (25.3, 27.3) 23.2 (22.3, 24.1) 1986 31.2 (30.0, 32.4) 34.3 (33.3, 35.3) 32.8 (32.0, 33.6) 1987 29.6 (28.4, 30.8) 33.9 (32.9, 34.9) 31.8 (31.0, 32.6) 1988 27.5 (26.5, 28.5) 31.5 (30.5, 32.5) 29.6 (28.8, 30.4) 1989 28.8 (27.8, 29.8) 33.6 (32.6, 34.6) 31.3 (30.5, 32.1) 1990 24.9 (23.9, 25.9) 32.4 (31.4, 33.4) 28.3 (28.0, 29.7) 28.6 (27.6, 29.6) 32.3 (31.3, 33.3) 30.5 (29.7, 31.3) 1991 21.4 (20.2, 22.6) 26.9 (25.8, 28.0) 24.3 (23.2, 25.3) 29.0 (28.0, 30.0) 32.8 (32.0, 33.6) 31.0 (30.4, 31.6) 1992 26.7 (25.9, 27.5) 31.4 (30.6, 32.2). 29.2 (28.6, 29.8) 1993 1994 28.7 (27.9, 29.5) 33.0 (32.2, 33.8) 30.9 (30.3, 31.5) Regular, sustained activity 1985 27.5 (26.6, 28.4) 22.5 (21.7, 23.3) 24.9 (24.2, 25.5) 1986 19.5 (18.5, 20.5) 18.1 (17.3, 18.9) 18.8 (18.2, 19.4) 1987 20.0 (18.8, 21.2) 17.6 (16.8, 18.4) 18.8 (18.2, 19.4) 1988 20.5 (19.5, 21.5) 19.6 (18.8, 20.4) 20.0 (19.4, 20.6) 1989 20.0 (19.0, 21.0) 18.0 (17.2, 18.8) 19.0 (18.4, 19.6) 1990 29.0 (28.1, 29.9) 22.7 (22.0, 23.4) 25.7 (25.1, 26.3) 20.5 (19.5, 21.5) 18.5 (17.7, 19.3) 19.4 (18.8, 20.0) 1991 26.6 (25.7, 27.5) 20.7 (19.9, 21.5) 23.5 (22.9, 24.1) 19.5 (18.7, 20.3) 18.3 (17.5, 19.1) 18.9 (18.3, 19.5) 1992 21.0 (20.2, 21.8) 18.4 (17.8, 19.0) 19.7 (19.1, 20.3) 1993 1994 19.3 (18.5, 20.1) 18.1 (17.5, 18.7) 18.7 (18.1, 19.3) Regular, vigorous activity 1985 17.2 (16.1, 18.3) 15.1 (14.3, 15.8) 16.1 (15.3, 16.8) 1986 11.2 (10.4, 12.0) 10.3 (9.7, 10.9) 10.7 (10.1, 11.3) 1987 10.7 (9.9, 11.5) 10.6 (10.0, 11.2) 10.7 (10.1, 11.31 1988 11.1 (10.3, 11.9) 12.3 (11.5, 13.1) 11.7 (11.1, 12.3) 1989 11.3 (10.5, 12.1) 11.9 (11.3, 12.5) 11.6 (11.2, 12.0) 1990 18.9 (18.1, 19.7) 15.9 (15.3, 16.4) 17.3 (16.8, 17.8) 11.0 (10.2, 11.8) 12.9 (12.3, 13.5) 12.0 (11.6, 12.4) 1991 18.1 (17.4, 18.8) 14.9 (14.3, 15.5) 16.4 (15.9, 16.9) 11.2 (10.6, 11.8) 12.6 (12.0, 13.2) 11.9 (11.5, 12.3) 1992 11.8 (11.2, 12.4) 12.2 (11.6, 12.8) 12.0 (11.6, 12.4) 1993 1994 11.4 (10.8, 12.0) 11.4 (10.8, 12.0) 11.4 (11.0, 11.8) Sources: Centers for Disease Control and PreventIon, National Center for Health Statistics, NHIS, 1985, 1990, 1991; Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, BRFSS, 1986-1992 and 1994. `25 states and the District of Columbia `95% confidence intervals. questions, and the age of respondents. Trends over Physical Inactivity time can be monitored only with the YRBS, which Healthy People 2000 objective 1.5 calls for reducing was conducted in 1991 and 1993 as well as in 1995. to no more than 15 percent the proportion of people An assessment of the test-retest reliability of the aged 6 years and older who are inactive (USDHHS YRBS indicated that the four physical activity items 1990). For this report, inactivity was defined as included in the study had a kappa value (an indicator performing no vigorous activity (exercise or sports of reliability) in the "substantial" (i.e., 61-80) or "al- participation that made the respondent "sweat or most perfect" (i.e., 81-100) range (Brener et al. 1995). breathe hard" for at least 20 minutes) and performing 188 Figure 5-3. Trends in leisure-time physical activity of adults aged 18+ years, NHIS 40 r 01 1985 1990 1991 Year Figure 5-4. Trends in the percentage of adults aged 18+ years participating in no leisure-time activity, BRFSS* 40 r Ior Men 10 1 L `D&I wtrlcted to the 25 states and D.C. for which data were available for each oi the5e years O--I I I I I I J 1986 1987 1988 1989 1990 1991 1992 1994 Year no light to moderate activity (walking or bicycling for at least 30 minutes) during any' of the 7 days preceding the survey. Among 12- through 21-year- olds surveyed in the 1992 NHIS-YRBS, the preva- lence of inactivity in the previous week was 13.7 percent and was higher among females than males (15.3 percentvs. 12.1 percent) (Table S-9). Overall, there was no difference among racial and ethnic groups, but black females had a higher prevalence Patterns and Trends in Physical Activity than white females (20.2 percent vs. 13.7 percent). For both males and females, inactivity increased with age. Similarly, in the 1995 school-based YRBS, the prevalence of inactivity in the previous week was 10.4 percent (Table 5-9) and was higher among females than males (13.8 percent vs. 7.3 percent). The prevalence was higher among black students than white students (15.3 percent vs. 9.3 percent) and among black females than white females (21.4 percent vs. 11.6 percent). Among female high school students, a substantial increase in inactivity was reported in the upper grades. Thus the Healthy People 2000 goal for inactivity has been met for adolescents overall but not for black females or for young adults. Vigorous Physical Activity Healthy People 2000 objective 1.4 (USDHHS 1990) proposes to increase to at least 75 percent the pro- portion of children and adolescents aged 6-17 years who engage in vigorous physical activity that pro- motes cardiorespiratory fitness 3 days or more per week for 20 minutes or more per occasion. In the 1992 NHIS-YRBS, 53.7 percent of 12- through 21- year-olds reported having exercised or taken part in sports that made them "sweat and breathe hard" during 3 or more of the 7 days preceding the survey (Table 5-10). However, one-fourth reported no vig- orous activity during the same time period. Prevalences of vigorous activity were higher among males than females (60.2 percent vs. 47.2 percent) and among white youths than Hispanic youths (54.6 percent vs. 49.5 percent) (Table 5-10). Vigorous physical activity declined with age. Among males, the prevalence of vigorous activity was at least 60 percent for those aged 12-17 years but was lower at older ages (e.g., 42.2 percent among 21-year-olds). Among females aged 12-14 years, the prevalence was at least 60 percent but was lower at older ages (e.g., 30.2 percent among 21-year-olds). The preva- lence of vigorous activity was associated positively with income and was higher during the spring than during other seasons. In the 1995 YRBS, 63.7 percent of students in grades 9-12 reported having exercised or taken part in sports that made them "sweat and breathe hard" for at least 20 minutes during 3 or more of the 7 days 189 Physical Activity and Health Table 5-9. Percentage of young people reporting no participation in vigorous or moderate physical activity during any of the 7 days preceding the survey, by demographic group, 1992 yational Health Interview Survey-Youth Risk Behavior Survey (NHIS-YRBS) and 1995 Youth Risk Behavior Survey (YRBS), United States Demographic group 1992 NHIS-YRBS* 1995 YRBS+ Overall 13.7 (12.9, 14.5? Sex Males Females 12.1 (11.0, 13.2) 15.3 (14.1, 16.5) Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females 13.4 (12.4, 14.5) 13.1 (11.7, 14.6) 13.7 (12.4, 15.1) 14.7 (12.7, 16.6) 9.2 (6.9, 11.5) 20.2 (17.0, 23.5) 14.3 (12.4, 16.3) 11.1 (8.4, 13.8) 17.8 (14.9, 20.7) Age (years) Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 7.7 (5.1, 10.2) 6.0 (3.6, 8.3) 3.6 (2.1, 5.1) 6.3 (3.7, 8.9) 9.6 (6.8, 12.4) 10.5 (7.2, 13.9) 18.8 (14.4, 23.3) 18.6 (14.7; 22.5) 22.3 (17.9, 26.8) 18.1 (14.3, 21.9) 8.4 (5.2, 11.5) 6.8 (4.4, 9.2) 8.3 (5.1, 11.5) 9.8 (7.0, 12.6) 14.4 (10.9, 17.9) 16.8 (13.2, 20.3) 18.7 (14.5, 22.8) 22.3 (18.1, 26.5) 25.0 (21.0, 28.9) 19.6 (16.4, 22.9) Annual family income < $10,000 $10,000-19,999 $20,000-34,999 $35,000-49,999 13.8 (11.6, 15.9) 14.9 (12.6, 17.3) 16.0 (14.1, 17.9) 12.2 (10.6, 13.8) 10.4 (9.0, 11.9) 7.3 (6.5, 8.1) 13.8 (11.2, 16.3) Grade in school Males 9.3 (7.9, 10.7) 7.3 (6.4, 8.1) 11.6 (8.7, 14.4) 15.3 (12.4, 18.2) 8.1 (5.4, 10.7) 21.4 (16.9, 25.8) 11.3 (8.6, 14.1) 7.5 (5.1, 9.9) 15.0 (10.6, 19.5) 9 6.0 (3.4, 8.7) 10 5.2 (3.0, 7.4) 11 7.9 (4.3, 11.4) 12 10.0 (7.4, 12.5) Females 9 8.7 (6.1, 11.3) 10 9.2 (7.3, 11.0) 11 17.8 (13.6, 22.0) 12 18.5 (13.3, 23.7) $50,000+ 11.2 (9.8, 12.7) Sources: Centers for Disease Control and Prevention, National Center for Health Statistics, NHIS-YRBS, 1992 machine readable data file and documentation, 1993; Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape (in press). *A national household-based survey oi youths aged 12-21 years. `A national school-based survey oi students in grades 9-12. `95% confidence intervals. 190 Patterns and Trends in Physical Activity Table 5-l 0. Percentage of young people reporting participation in vigorous physical activity during 3 or more of the 7 days preceding the survey, by demographic group, 1992 National Health Interview Survey-Youth Risk Behavior Survey (NHIS-YRBS) and 1995 Youth Risk Behavior Survey (YRBS), United States Demographic group 1992 NHIS-YRBS* 1995 YRBS+ Overall 53.7 (52.5, 54.9)' 63.7 (60.4, 66.9) Sex Males Females 60.2 (58.6, 61.8) 74.4 (72.1, 76.6) 47.2 (45.6, 48.8) 52.1 (47.5, 56.8) Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females 54.6 (53.2, 56.0) 67.0 (62.6, 71.4) 60.2 (58.4, 62.0) 16.0 (73.0, 78.9) 49.0 (46.8, 51.2) 56.7 ( 50.0, 63.4) 52.6 (49.9, 55.3) 53.2 (49.6, 56.8) 62.7 (58.8, 66.6) 68.1 (62.8, 73.4) 42.3 (38.6, 46.0) 41.3 (35.5, 42.1) 49.5 (46.6, 52.4) 57.3 (53.7, 60.9) 56.7 (52.6, 60.8) 69.7 (64.9, 74.5) 41.7 (38.2, 45.2) 45.2 (39.9, 50.6) Age (years) Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 70.8 (66.7, 74.9) 73.7 (69.4, 78.0) 76.1 (72.2, 80.0) 72.6 (68.1, 71.1) 65.6 (60.3, 70.9) 60.2 (54.7, 65.7) 48.4 (43.1, 53.7) 44.1 (38.4, 49.8) 43.4' (38.5, 48.3) 42.2 (37.1, 47.3) Grade in school Males 9 80.8 (75.9, 85.6) 10 75.9 (72.5, 79.3) 11 70.2 (67.5, 72.9) 12 66.9 (63.0, 70.7) Females 66.2 (62.1, 70.3) 63.1 (58.0, 68.2) 63.1 (58.4, 67.8) 56.6 (51.9, 61.3) 50.9 (45.6, 56.2) 43.6 (38.1, 49.1) 37.5 (32.2, 42.8) 32.6 (27.3, 37.9) 28.2 (23.9, 32.5) 30.2 (25.5, 34.9) 9 60.9 (54.8, 67.0) 10 54.4 (47.6, 61.3) 11 44.7 (40.6, 48.9) 12 41.0 (34.6, 47.5) Annual family income < $10,000 $10,000-19,999 $20,000-34,999 $35,000-49,999 $50,000+ 46.7 (43.2, 50.2) 4i.5 (46.0, 51.1) 55.0 (52.5, 57.6) 58.4 (55.5, 61.3) 60.2 (57.9, 62.6) Sources: Centers for Disease Control and Prevention, National Center for Health Statistics, NHIS-YRBS, 1992 machine readable data file and documentatron, 1993; Centers for Disease Control and Prevention, Natronal Center for Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape fin press). *A national household-based survey of youths aged 12-2 1 Years. `A natronal school-based survey of students in grades 9-l 2. `9S% confidence intervals. 191 physical Activity and Health preceding the survey (Table 5-10). However, 16.0 percent reported no vigorous physical activity dur- ing the same time period. Subgroup patterns were similar to those reported for the NHIS-YRBS. Vigor- ous physical activity was more common among male than female students (74.4 percent vs. 52.1 percent) and among white than black or Hispanic students (67 percent vs. 53.2 percent and 57.3 percent, re- spectively). Among both male and female students, vigorous activity was less common in the upper grades. From 1991 through 1995, the overall preva- lence did not change significantly among students in grades 9-12 (data not shown). NHIS-YRBS and YRBS data clearly show that the prevalence ofvigorous physical activity among young people falls short of the Healclty People 2000 goal of 75 percent. Other Physical Activity Healthy People 2000 objective 1.6 (USDHHS 1990) aims for at least 40 percent of people aged 6 and older to regularly perform physical activities that enhance and maintain muscular strength, muscular endur- ance, and flexibility. The 1992 NHIS-YRBS indicated that 45.6 percent of 12- through 21-year-olds had participated instrengtheningor toningactivities (e.g., push-ups, sit-ups, or weight lifting) during at least 3 of the 7 days preceding the survey (Table 5- 11). These activities were more common among males than females (54.6 percent vs. 36.4 percent) and among white and Hispanic youths than black youths (46.4 percent and 45.4 percent, respectively, vs. 39.8 per- cent). Among both males and females, the prevalence of strengthening or toning activities decreased as age increased and was greater among young people living in households with higher incomes. Similar to the NHIS-YRBS, the 1995 YRBS indi- cated that 50.3 percent ofstudentsin grades9-12 had participated in strengthening or toning activities dur- ing at least 3 of the 7 days preceding the survey (Table 5-11). Subgroup patterns were similar to those re- ported for the 1992 NHIS-YRBS. Male students were more likely than female students to participate in strengthening or toning activities (59.1 percent vs. 41.0 percent), and white students were more likely than black students to do so (52.8 percent vs. 41.4 percent). Among female students, participation was greater among those in lower grades, but this practice did not vary by grade among male students. Between 1991 and 1995, the overall prevalence of strengthening or toning activities among students in grades 9-12 did not change (data not shown). In the 1992 NHIS-YRBS, 48.0 percent of 12- through 21-year-olds reported having participated instretchingactivities (e.g., toe touching, knee bend- ing, ot leg stretching) during at least 3 of the 7 days preceding the survey. White and Hispanic youths were more likely than black youths to report this (49.2 percent and485 percent, respectively, vs. 40.7 percent). Overall, the prevalence of stretching activi- ties did not differ by sex, although these activities were more common among black males than among black females (44.9 percent vs. 36.5 percent). Among both males and females, the prevalence was higher in the younger age categories. Participation was also higher with higher family income. In the 1995 YRBS, 53.0 percent of students in grades 9-12 reported having participated in stretch- ing activities during at least 3 of the 7 days preceding the survey (Table 5-12). Subgroup patterns were generally similar to those reported for the NHIS- YRBS. Similar proportions of male and female stu- dents participated in stretching activities (55.5 percent and 50.4 percent, respectively), and white students were more likely than black students to do so (55.1 percent vs. 45.4 percent). Participation in stretching activities declined across grades for both male and female students. Between 1991 and 1995, the overall prevalence among students in grades 9-12 did not change significantly (data not shown). Thus the Healthy People 2000 objective for strengthening and stretching activities has been met overall among adolescents and young adults but not among all subgroups. Healthy People 2000 objective 1.3 (USDHHS 1990) proposes to increase to at least 30 percent the proportion of people aged 6 and older who engage regularly, preferably daily, in light to moderate physi- cal activity for at least 30 minutes per day. Walking and bicycling can be used to measure light to mod- erate physical activity among young people. In the 1992 NHIS-YRBS, 26.4 percent of 12- through 21- year-olds reported having walked or bicycled for 30 minutes or more on at least 5 of the 7 days preceding the survey (Table 5-13). These activities were more common among males than females (29.1 percent vs. 23.7 percent) and among Hispanic youths than 192 Patterns and Trends in Physical Activity Table 5-11. Percentage of young people reporting participation in strengthening or toning activities during 3 or more of the 7 days preceding the survey, by demographic group, 1992 National Health Interview Survey-Youth Risk Behavior Survey (NHIS-YRBS) and 1995 Youth Risk Behavior Survey (YRBS), United States Demographic group 1992 NHIS-YRBS' 1995 YRBS+ Overall 45.6 (44.4, 46.8)* 50.3 (46.6, 54.0) Sex Males Females 54.6 (53.0, 56.2) 59.1 (56.1, 62.1) 36.4 (34.8, 38.0) 41.0 (36.0, 46.0) Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females 46.4 (45.0, 47.8) 52.8 (47.2, 58.4) 54.4 (52.6, 56.2) 60.3 (56.4, 64.2) 38.4 (36.4, 40.4) 24.4 (36.4, 2.4) 39.8 (37.5, 42.2) 41.4 (37.9, 45.0) 53.2 (49.3, 57.1) 54.2 (49.7, 58.6) 26.2 (23.1, 29.3) 31.3 (26.7, 35.9) 45.4 (42.5, 48.3) 47.4 (41.8, 53.1) 53.3 (49.4, 57.2) 57.8 (51.9, 63.8) 36.9 (33.2, 40.6) 37.4 (29.6, 45.2) Age (yeaN Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 Grade in school Males 59.4 (54.7, 64.1) 66.3 (62.2, 70.4) 61.1 (56.0, 66.2) 66.6 (61.9, 71.3) 61.3 (56.0, 66.6) 53.9 (48.6, 59.2) 46.0 (41.3, 50.7) 45.2 (39.7, 50.7) 42.0 (37.5, 46.5) 40.5 (35.8, 45.2) 9 65.3 (58.0, 72.5) 10 60.0 (55.8, 64.2) 11 55.9 (52.5, 59.2) 12 54.7 (49.7, 59.7) Females 43.9 (39.6, 48.2) 46.9 (41.6, 52.2) 47.6 (42.7, 52.5) 44.0 (39.1, 48.9) 38.1 (33.6, 42.6) 37.1 (32.0, 42.2) 31.1 (25.6, 36.6) 26.4 (22.1, 30.7) 26.3 (22.0, 30.6) 23.2 (19.3, 27.1) 9 51.3 (42.9, 59.8) 10 45.6 (38.3, 53.0) 11 31.0 (27.6, 34.3) 12 30.0 (25.1, 34.9) 36.4 (33.7, 39.1) 44.6 (41.9, 47.3) 46.5 (44.0, 49.1) 49.6 (46.7, 52.5) Annual family income <$10,000 $10,000-$19,999 $20,000-$34,999 $35,000-$49,999 $50,000+ 51.4 (49.1, 53.8) Sources: Centers for Disease Control and Prevention, National Center ior Health Statrstics, NHIS-YRBS.1992 machine readable data iile and documentatron, 1993; Centers for Disease Control and Prevention, National Center ior Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape trn press). `A national household-based survey oi youths aged 12-21 years. `A national school-based survey oi students in grades 9-l 2. `95% coniidence intervals. 193 Physical Activity and Health Table 5-12. Percentage of young people reporting participation in stretching activities during 3 or more of the 7 days preceding the survey, by demographic group, 1992 National Health Interview Survey-Youth Risk Behavior Survey (NHIS-YRBS) and 1995 Youth Risk Behavior Survey (YRBS), United States Demographic group 1992 NHIS-YRBS' 1995 YRBS+ Overall 48.0 (46.8, 49.2)' Sex Males Females 48.2 (46.6, 49.8) 47.9 (46.3, 49.5) Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females 49.2 (47.8, 50.6) 55.1 (50.8, 59.3) 48.0 (46.0, 50.0) 56.1 (52.1, 60.1) 50.4 (48.4, 52.4) 53.9 (48.2,' 59.5) 40.7 (38.0, 43.4) 45.4 (41.7, 49.0) 44.9 (41 .o, 48.81 50.5 (45.0, 55.9) 36.5 (32.8, 40.2) 41.5 (36.6, 46.3 48.5 (45.8, 51.2) 49.1 (45.0, 53.2) 49.9 (46.0, 53.8) 54.8 (50.1, 59.6) 47.0 (43.3, 50.7) 43.5 (37.6, 49.5) Age (years) Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 Grade in school Males 55.4 (50.5, 60.3) 62.0 (57.3, 66.7) 57.9 (53.2, 62.6) 56.1 (51.0, 61.2) 54.0 (48.7, 59.3) 48.2 (42.9, 53.5) 36.2 (31.1, 41.3) 36.7 (32.0, 41.4) 32.9 (28.4, 37.4) 38.5 (33.4, 43.6) 9 65.7 (58.9, 72.6) 10 51.1 (47.8, 54.4) 11 52.9 (48.1, 57.6) 12 49.8 (42.0, 57.7) Females 62.5 (58.0, 67.0) 62.5 (57.2, 67.8) 61.6 (56.7, 66.51 57.9 (53.0, 62.8) 52.0 (47.1, 56.9) 42.0 (37.1, 46.9) 38.5 (33.0, 44.0) 33.1 (28.0, 38.2) 33.9 (29.6, 38.2) 35.0 (30.9, 39.1) 9 59.9 (52.8, 67.0) 10 55.8 (49.6, 61.9) 11 39.5 (33.7, 45.3) 12 38.4 (32.7, 44.1) 40.8 (37.7,. 43.9) 44.5 (41.8, 47.2) 48.2 (45.9, 50.6) 51.9 (49.2, 54.6) Annual family income < $10,000 $10,000-$19,999 $20,000-$34,999 $35,000-$49,999 4 50,000+ 54.2 (51.7, 56.8) Sources: Centers for Disease Control and Prevention, National Center ior Health Statistics, NHIS-`fRt%, 199.7 machine readable data file and documentation, 1993; Centers for Disease Control and Preventton, National Center for Chronic Disease Preventjon and Health Promotion, YRBS 1995 data tape (in press). *A national household-based survey of youths aged 12-21 years. `A national school-based survey oi students in grades 9-l 2. `95% confidence intervals. 53.0 (49.9, 56.2) 55.5 (52.3, 58.7) 50.4 (46.6, 54.3) 194 Patterns and Trends in Physical Activity Table 5-l 3. Percentage of young people reporting participation in walking or bicycling for 30 minutes or more during 5 or more of the 7 days preceding the survey, by demographic group, 1992 National Health Interview Survey-Youth Risk Behavior Survey (NHIS-YRBS) and 1995 Youth Risk Behavior Survey (YRBS), United States Demographic group 1992 NHIS-YRBS* 1995 YRBS+ Overall 26.4 (25.4, 27.4)' 21.1 (18.7, 23.5) Sex Males Females 29.1 (27.5, 30.7) 21.6 (18.4, 24.8) 23.7 (22.3, 25.1) 20.5 (17.8, 23.2) Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females 25.1 (23.9, 26.3) 18.3 (15.0, 21.6) 27.5 (25.7, 29.3) 19.7 (15.5, 23.8) 22.7 (21.1, 24.3) 16.8 (13.9, 19.8) 26.9 (24.6, 29.2) 27.0 (23.2, 30.9) 29.8 (26.7, 32.9) 27.2 (23.2, 31.2) 23.9 (20.2, 27.6) 26.4 (20.8, 32.0) 32.3 (29.8, 34.9) 26.8 (22.6, 31.0) 35.5 (31.6, 39.4) 26.0 (19.9, 32.1) 28.8 (25.5, 32.1) 27.6 (23.8, 31.5) Age (years) Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 38.9 (34.6, 43.2) 37.3 (32.4, 42.2) 35.3 (31.2, 39.4) 33.9 (29.0, 38.8) 29.9 (25.6, 34.2) 22.2 (17.7, 26.7) 23.3 (18.6, 28.0) 21.3 (17.2, 25.4) 22.0 (17.9, 26.1) 23.3. (19.0, 27.6) Grade in school Males 9 27.9 (22.1, 33.7) 10 21.7 (17.8, 25.6) 11 19.2 (16.2, 22.1) 12 17.7 (13.1, 22.3) Females 32.2 (28.1, 36.3) 28.5 (24.0, 33.0) 28.7 (23.8, 33.6) 22.9 (18.8, 27.0) 22.9 (1 8.8, 27.0) 19.4 (1 5.5, 23.3) 20.1 (1 6.0, 24.2) 18.8 (1 4.5, 23.1) 20.8 (1 6.7, 24.9) 22.1 (1 8.4, 25.8) 9 22.5 (18.5, 26.5) 10 22.8 (18.5, 27.2) 11 16.8 (13.3, 20.3) 12 76.1 (11.6, 20.6) Annual family income < $10,000 $10,000-$19,999 $20,000-$34,999 $35,000-$49,999 $50,000+ 27.8 (25.1, 30.5) 29.5 (26.8, 32.2) 27:6 (25.2, 30.0) 25.5 (23.2, 27.9) 23.5 (21.5, 25.5) Sources: Centers for Disease Control and Prevention, National Center for Health Statistics, NHIS-YRBS, 1992 machine readable data fife and documentation, 1993; Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape (in press). *A national household-based survey of youths aged 12-21 years. `A national school-based survey of students in grades 9-l 2. `95% confidence intervals. 195 Physical Activity and Health Table 5-l 4. Percentage of young people reporting participation in selected physical activities during 1 or more of the 7 days preceding the survey, by demographic group, 1992 National Health Interview Survey- Youth Risk Behavior Survey (NHIS-YRBS),' United States - Aerobics Baseball, softball, Basketball, football, Demographic group or dancing or Frisbee@ or soccer - Overall 38.2 (37.1,39.2)+ 22.4 (21.4,23.4) 45.8 (44.6,47.1) Sex Males Females Race/Ethnicity White, non-Hispanic Black, non-Hispanic Hispanic Age (years) Males 12 13 14 15 16 17 18 19 20 21 Females 12 13 14 15 16 17 18 19 20 21 22.6 (21.3,24.0) 27.2 (25.7,28.8) 61.7 (60.fI63.3) 53.9 (52.4,55.5) 17.5 (16.4,18.7) 29.7 (28.2,31.3) 35.0 (33.7,36.2) 23.6 (22.3,24.9) 44.7 i43.1,46.2) 49.4 (46.6,52.1) 16.6 (14.3,18.9) 49.5 (46.7,52.3) 42.0 (39.0,45.0) 23.4 (21.1,25.7) 47.1 (44.4,49.8) 26.9 (22.5,31.2) 46.4 (41.6,51.3) 81.2 (77.4,85.0) 23.4 (19.6,27.3) 40.6 (35.8,45.3) 84.3 (80.8,87.9) 22.0 (18.4,25.7) 40.9 (36.6,45.2) 78.5 (74.3,82.6) 21.9 (17.7,26.1) 25.6 (21.0,30.3) 76.7 (72.5,81.0) 24.5 (20.2,28.9) 27.4 (22.9,31.9) 69.6 (64.5,74.6) 20.8 (16.8,24.6) 22.5 (18.1,26.9) 59.3 (54.2,64.3) 19.0 (14.9,23.1) 20.8 (16.3,25.2) 54.6 (49.1,60.0) 24.0 (19.6,28.4) 17.5 (13.8,21.2) 43.8 (38.5,49.0) 21.2 (17.2,25.2) 17.0 (13.3,20.8) 38.5 (33.9,43.2) 21.4 (17.2,25.7) 15.6 (12.1,lq.l) 32.4 (27.6,37.1) 63.1 (58.7,67.5) 37.9 (33.4,42.5) 63.7 (59.5,67.9) 30.3 (26.2,34.3) 63.7 (59.0,68.3) 29.1 (24.7,33.5) 62.0 (57.5,66.4) 22.6 (18.3,26.9) 55.7 (50.5,60.9) 16.0 (12.3,19.6) 54.0 (48.8,59.2) 10.2 (7.4,13.1) 50.3 (45.2,55.5) 11.4 (7.3,15.4) 44.8 (39.1,50.4) 6.9 (4.4, 9.3) 40.7 (36.2,45.2) 7.6 (4.8,10.4) 45.6 (41.0,50.2) 8.4 (5.9,10.9) white or black youths (32.3 percent vs. 25.1 p¢ and 26.9 percent, respectively). Walking or bicy- cling decreased as age increased and was more preva- lent in the fall than in other seasons. In the 1995 YRBS, 21.1 percent of students in grades 9-12 reported having walked or bicycled for 30 minutes or more on at least 5 of the 7 days preceding the survey (Table 5-13). Male and female students reported similar prevalences of these activi- ties. Black and Hispanic students were more likely 62.6 (57.6,67.6) 61.6 (56.9,66.3) 51.9 (46.8,57.1) 41.6 (37.2,46.1) 28.0 (23.3,32.6) 23.4 (19.0,27.7) 13.8 (10.2,17.4) 8.5 (6.0, 11.0) 6.9 (4.7, 9.1) 7.5 (5.2, 9.8) than white students to have walked or bicycled (27.0 percent and 26.8 percent, respectively, vs. 18.3 per- cent). Between 1993 and 1995, the overall preva- lence among students in grades 9-12 did not change significantly (data not shown). It thus appears that the Healthy People 2000 objective for light to moderate physical activity has not been attained by adolescents and young adults. The 1992 NHIS-YRBS provided information on participation in seven additional types of physical 196 Patterns and Trends in Physical Activity Table 5-14. Continued House cleaning or yard work for 2 30 minutes 82.8 (81.7, 83.8) Running, jogging, or swimming 55.3 (54.1,56.6) Skating, skiing, or skateboarding 13.3 (12.5,14.0) Tennis, raquetball, or squash 10.5 (9.8, 11.2) 78.1 (76.6, 79.5) 57.6 (55.9,59.3) 15.9 87.5 (86.3, 88.7) 53.0 (51.4,54.7) 10.6 83.1 (81.9, 84.3) 55.8 (54.3,57.3) 15.2 84.2 (81.9, 86.5) 52.4 (49.5,55.3) 9.0 80.1 (77.9, 82.4) 53.6 (50.9,56.4) 9.8 14.8,17.0) 11.7 (10.7,12.8) (9.6, 11.5) 9.3 (8.4,10.2) 14.2,16.2) 11.4 (10.6,12.3) (7.3,10.8) 5.4 (4.2, 6.6) (8.2, 11.5) 8.0 (6.7, 9.4) 76.9 (72.9, 81.0) 72.8 (68.3,77.3) 32.5 (27.8,37.3) 14.4 (10.8,18.0) 83.3 (80.1, 86.5) 74.3 (70.1,78.4) 26.2 (22.1,30.3) 13.3 (10.3,16.4) 79.4 (75.5, 83.4) 71.2 (66.8,75.6) 20.7 (16.9,24.5) 14.5 (11.3,17.8) 82.9(79.3, 86.5) 70.8 (66.5,75.1) 19.9 (15.9,23.9) 15.3 (11.7,lB.g) 79.6 (75.7, 83.6) 63.4 (58.8,68.1) 13.4 (10.0,16.8) 10.4 (7.4, 13.3) 78.7 (74.5, 82.9) 55.3 (49.9,60.7) 12.2 (8.6,15.7) 11.3 (8.0,14.6) 70.9 (65.9, 75.9) 47.4 (42.2,52.5) 9.4 (6.3,12.4) 11.6 (8.3,14.9) 75.0(69.6, 80.4) 74.4 (70.3, 78.5) 77.6 (73.7, 81.5) 88.0 (84.8, 91.2) 88.1 (85.1, 91 .l) 87.2 (83.9, 90.4) 88.5 (85.3, 91.7) 89.1 (85.7, 92.5) 86.0 (82.6, 89.4) 87.0 (83.4, 90.5) 82.6 (78.1, 87.1) 87.1 (83.0, 91.2) 89.8 (86.2, 93.4) 46.3 (41.3,51.2) 34.4 (29.9,38.9) 39.8 (34.1,45.5) 80.5 (76.4,84.53 76.2 (72.1,80.3) 72.9 (68.6,77.2) 65.4 (60.7,70.1) 59.7 (54.8,64.6) 49.0 (43.5,54.4) 41.5 (35.8,47.3) 32.9 (27.8,38.0) 30.8 (25.8,35.7) 30.3 (26.0,34.6) 10.8 (7.7, 14.0) 8.6 (6.1, 11.2) 5.9 (3.8, 7.9) 24.9 (20.5,29.3) 19.7 (16.1,23.4) 14.8 (11.6,18.0) 10.0 (7.0, 12.9) 8.9 (6.2, 11.7) 4.8 (2.7, 6.8) 8.1 (5.5,10.7) 6.6 (4.1, 9.1) 5.8 (3.5, 8.0) 4.8 (3.1, 6.6) 9.9 (6.9,12.8) 8.2 (5.5,lO.a) 9.5 (6.5,12.5) 13.9 12.4 13.0 16.1 11.1 8.0 6.9 3.8 5.8 4.1 10.5,17.3) (9.2,15.6) 10.0,15.9) 12.6,19.6) (8.0,14.2) (5.4,10.5) (4.4, 9.5) (2.1, 5.4) (3.6, 8.0) (2.2, 5.9) Source: Centers for Disease Control and Prevention. National Center for Health Statistics, NHIS-YRBS, 1992 machine readable data file and documentation, 1993. *A national household-based survey of youths aged 12-21 years. `95% confidence intervals. activity during 1 or more of the 7 days preceding the survey: aerobics or dancing; baseball, softball, or Frisbee@`; basketball, football, or soccer; houseclean- ing or yard work for at least 30 minutes; running, jogging, or swimming for exercise; skating, skiing, or skateboarding; and tennis, racquetball, or squash (Table 5-14). Among 12- through 21-year- olds, males were more likely than females to participate in baseball, softball, or Frisbee@; in basketball, football, or soccer; in running, jogging, or swimming for exercise; in skating, skiing, or `Use of trade names is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services. skateboarding; and in tennis, racquetball, or squash. 197 Physical Activity and Health Table 5-l 5. Percentage of students in grades 9-T 2 reporting enrollment in physical education class, daily attendance in physical education class, and participation in exercise or sports for at least 20 minutes during an average physical education class, by demographic group, 1995 Youth Risk Behavior Survey (YRBS),' United States Demographic group Enrolled in Attended physical Exercised or played sports physical education education daily 2 20 minutes per class+ Overall 59.6(48.6, 70.5? 25.4 (15.8, 34.9) 69.7 (66.4,72.9) Sex Males Females 62.2 (52.5,71.8) 27.0 (16.8, 37.2) 74.8 (71.8, 77.8) 56.8 (44.1, 69.6) 23.5 (14.5, 32.4) 63.7 (59.3,68.1) Race/Ethnicity White, non-Hispanic Males Females 62.9 (49.8, 76.1) 64.2 (52.6,75.8) 61.7(46.4, 77.0) Black, non-Hispanic 50.2(45.1,55.3) Males 56.8(50.6,62.9) Females 44.4(37.3,51.5) Hispanic 51.0(40.9,61.2) Males 57.6(48.6, 66.6) Females 44.6 (3 1.2, 58.0) 21.7 (9.9,33.5) 23.3 (11.2,35.3) 19.9 (8.0, 3 1.8) 33.8 (29.9,37.8) 37.7 (32.3,43.0) 30.1 (25.8,34.5) 33.1 (24.5,41.8) 36.2 (28.8,43.6) 30.1 (18.7, 41.5) 71.3 (67.d, 75.6) 74.8 (71.1,78.5) 67.1 (60.5, 73.8) 59.0 (54.6,63.3) 71.8 (65.9,77.8) 46.6 (39.3, 53.8) 68.5 (62.8, 74.1) 76.0 (67.0,85.0) 59.0 (52.5,65.6) Grade in school Males 9 10 11 12 80.5(75.1,85.9) 42.1 (23.3,60.8) 76.5 (72.2,80.9) 72.6 (62.3,82.8) 34.8 (18.9, 50.8) 73.1 (67.9, 78.3) 51.5 (32.8, 70.1) 17.4 (9.3, 25.6) 75.8 (70.3,81.2) 45.4(29.0,61.91 14.8 (9.2,20.4) 73.7 (68.1,79.3) Females 9 10 11 12 80.8 (73.8,87.8) 39.7 (21.5, 58.0) 65.6 (57.2, 74.1) 71.4(59.3,83.5) 33.8 (17.4, 50.3) 63.9 (58.8,68.9) 41.2 (22.8, 59.6) 12.3 (7.6,17.1) 57.2 (48.4,66.0) 39.1 (20.9, 57.2) 11.1 (6.5, 15.7) 66.0 (59.7,72.4) Source: Centers ior Disease Control and PreventIon, NatIonal Center t'or Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape (in press). `A national school-based survey of students in grades 9-12. `Among students enrolled in physical education. `95% confidence Intervals. Females were more likely than males to participate in aerobics or dancing and in house cleaning or skating, skiing, or skateboarding. For females, par- ticipation in aerobics or dancing and in tennis, racquetball, or squash also decreased by age. Physical Education in High School The YRBS provides data on enrollment and daily attendance in school physical education for students in grades 9-12. (See Chapter 6 for a discussion of the availability of physical education programs.) In 1995, yard work for at least 30 minutes. White youths were more likely than black or Hispanic youths to participate in skating, skiing, or skateboardingand in tennis, racquetball, or squash. For both males and females, increasing age was associated with decreasing participation in baseball, softball, or Frisbee@; in basketball, football, or soccer; in run- ning, jogging, or swimming for exercise; and in 198 Patterns and Trends in Physical Activity Fable 5-l 6. Percentage of students in grades 9-l 2 reporting participation on at least one sports team run by a school or by other organizations during the year preceding the survey, by demographic group, 1995 Youth Risk Behavior Survey (YRBS),* United States Demographic group Overall Sex Males Females Race/Ethnicity White, non-Hispanic Males Females Black, non-Hispanic Males Females Hispanic Males Females Grade in school Males 9 10 11 12 Females 9 10 11 Participation on sports team run by a school 50.3 (46.6, 54.0)+ 57.8 (53.7, 62.0) 42.4 (38.6, 46.2) 53.9(49.6, 58.2) 59.9 (54.8, 65.0) 47.1 (43.0, 51.2) 45.0 (39.9, 50.2) 57.9 (52.6, 63.2) 34.9 (28.2,41.7) 37.8(33.6,42.0) 48.6 (44.0, 53.2) 27.3 (21.9, 32.7) 61.7 (54.0, 6" -j 55.6 (50.1. :.l) 56.0 (49 _ 52.4) 58.3 (= w.0, 64.6) .3.7 (39.2,48.2) 47.9(42.8, 53.0) 39.4 (32.1, 46.7) Participation on sports team run by other organization 36.9(34.4, 39.4) 46.4(43.4,49.3) 26.8 (24.2, 29.4) 39.1'(35.7, 42.5) 47.2 (43.0, 51.4) 29.9 (26.8. 32.9) 32 4 (29.0 35.9) . 46.8 (42.4: 51.1) 21.1 (16.5, 25.8) 32.0 (28.5, 35.6) 43.2 (37.9, 48.4) 21.2 (16.5, 25.9) 52.8(47.0, 58.7) 46.9 (42.4, 51.4) 43.1 (40.6, 45.7) 42.8 (39.2,46.3) 32.0 (28.2, 35.9) 32.4(26.8, 38.0) 23.8 (19.9, 27.6) 12 38.8 (32.4; 45.1) 19.8 (15.2, 24.3) Source: Centers ior Disease Control a+ evention, National Center for Chronic Disease Prevention and Health Promotion, YRBS 1995 data tape (in press). `A national school-based surw .Y (! 1 ,n grades 9-l 2. +95'% confidence intervals. 59.6 tiercent ofsrudents in grades 9-12 were enrolled in -Iqsical education (Table 5-15). Enrollment did not vary by sex or rat .LF rcity, but it decreased by grade. Between 1991 3njA lW.3, overall enrollment in physical education am.)ng ` udents in grades 9-12 did not change sigmficantl- (data not shown). HeaIt/i> Pea: .e 2000 objective 1.8 (USDHHS 1990) recommr ;Ids increasing to at least 50 percent the propo; tion If children and adolescents in grades l- 12 11 ;ro parti;,pate in daily school physical education. I ne 1995 `iRBS indicated that daily attendance in physical education among high school students was 25.4 percent and did not vary by sex or race/ethnicity (Table 5-15). Daily attendance decreased with in- creasing grade for both male and female students. Between 1991 and 1995, overall daily attendance in physical education classes in grades 9-12 decreased significantly, from 41.6 percent to 25.4 percent (data not shown). Current trend data thus indicate that the Healthy People 2000 goal of 50 percent has not been attained and is also becoming more distant. Healthy People 2000 objective 1.9 (USDHHS 1990) recommends that students be active for at 199 Physical Activity and Health least 50 percent of the class time they spend in physical education. In 1995, 69.7 percent of stu- dents in grades 9-12 who were taking physical education reported being physically active for at least 20 minutes, which is about half of a typical class period (Table S-15). This active participa- tion was more common among male students than female students (74.8 percent vs. 63.7 percent) and among white students than black students (71.3 percent vs. 59.0 percent). Between 1991 and 1995, the overall percentage of students in grades 9-12 taking physical education who reported be- ing physically active for at least 20 minutes de- creased from 80.7 percent to 69.7 percent (data not shown). Decreases between 1991 or 1993 and 1995 occurred for students in all grades. Thus a decreasing proportion of the high school students who are enrolled in physical education classes are meeting the Healthy People 2000 goal for time spent being physically active in class. Only 18.6 percent of all high school students were physically active for at least 20 minutes on a daily basis in physical education classes (data not shown). Sports Team Participation The YRBS provides data on participation on sports teams during the 12 months preceding the survey for students in grades 9-12. In 1995, 50.3 percent of students participated on sports teams run by a school, and 36.9 percent participated on sports teams run by other organizations (Table 5-16). Participation on sports teams run by a school was more common among male students than female students (57.8 percent vs. 42.4 percent) and among white students than Hispanic students (53.9 per- cent vs. 37.8 percent). Between 1991 and 1995, participation on sports teams run by a school in- creased significantly among high school students overall, from 43.5 percent to 50.3 percent (data not shown). Specific increases were identified among female students, white and black students, and students in grades 11 and 12. Participation on sports teams run by other orga- nizations besides a school was more common among male students than female students (46.4 percent vs. 26.8 percent) and among white students than Hispanic students (39.1 percent vs. 32.0 percent). Between 1991 and 1995, overall participationamong students in grades 9-12 on sports teams run by other organizations did not change significantly (data not shown). Conclusions Adults 1. 2. 3. 4. 5. Approximately 15 percent of U.S. adults engage regularly (3 timesa week for at least 20 minutes) in vigorous physical activity during leisure time. Approximately 22 percent of adults engage regu- larly (5 times a week for at least 30 minutes) in sustained physical activity of any intensity dur- ing leisure time. About 25 percent of adults report no physical activity in their leisure time. Physical inactivity is more prevalent among women than men, among blacks and Hispanics than whites, among older than younger adults, and among the less affluent than the more affluent. The most popular leisure-time physical activities among adults are walking and gardening or yard work. Adolescents and Young Adults 1. 2. 3. 4. Only about one-half of U.S. young people (ages 12-21 years) regularly participate in vigorous physical activity. One-fourth report no vigorous physical activity. Approximately one-fourth of young people walk or bicycle (i.e., engage in light to moderate activ- ity) nearly every day. About 14 percent of young people report no recent vigorous or light to moderate physical activity. This indicator of inactivity is higher among females than males and among black females than white females. Males are more likely than females to participate in vigorous physical activity, strengthening ac- tivities, and walking or bicycling. 5. Participation in all types of physical activity declines strikingly as age or grade in school increases. 100