Physical Activity Among Adults: United States, 2000 and 2005

by Patricia Barnes, M.A., Division of Health Interview Statistics

The positive influence that physical activity has on health has been well established. Among adults, regular physical activity has been associated with a reduced risk of stroke (1), impaired glucose tolerance (2), Type 2 diabetes (2), mortality (3), and cardiovascular disease incident events (3). Engaging in physical activity daily has also proven to be helpful in both losing weight and maintaining weight loss (4). This report compares national estimates of physical activity, both usual daily activity and leisure-time physical activity, among adults based on responses to the physical activity questions found in the 2000 and 2005 National Health Interview Surveys (NHIS).

Methods

NHIS, a survey of the noninstitutionalized civilian population of the United States, has been an important source of information about health and health care in the United States since it was first conducted in 1957. NHIS is a multistage probability sample survey that is conducted continuously throughout the year by interviewers of the U. S. Census Bureau for the Centers for Disease Control and Prevention’s National Center for Health Statistics. For further information see the NHIS website.

In addition to the usual NHIS core questions about leisure-time physical activity, two supplements—the 2000 Cancer Control Module and the 2005 Adult Cancer Control Supplement—contained questions about usual daily activity related to moving around (sitting, standing, and walking) and lifting or carrying things (no lifting; lifting light, moderate, or heavy loads). The tables in this report show 2000 and 2005 estimates for usual daily activity and leisure-time physical activity separately as well as combined into an overall indicator of total physical activity. Data for years 2000 and 2005 were used because these are the only years that contain questions about both leisure-time physical activity and usual daily activity.

Estimates shown in this report were calculated excluding unknowns (i.e., refused, not ascertained, or don’t know). Item nonresponse for the activity questions ranged from 1.3% to 7.0%. Point estimates and estimates of corresponding variances were calculated using the SUDAAN software package (5) to account for the complex sample design of the NHIS. The Taylor series linearization method was chosen for variance estimation. Differences between percentages were evaluated using two-sided significance tests at the 0.05 level. Terms such as "greater than" or "less than" indicate a statistically significant difference. Terms such as "similar" and "no difference" indicate that the estimates being compared were not significantly different. Lack of comments regarding the difference between any two estimates does not necessarily mean that the difference was tested and found to be not significant. All estimates shown meet the NCHS standard of having less than or equal to 30% relative standard error.

Results

Between 2000 and 2005, there was little change in the percentage of adults engaging in usual daily activities and leisure-time physical activities (Tables 1–4 [PDF - 28 KB]). The changes in estimates that occurred were generally not significant. In instances where differences were statistically significant, adults were less active in 2005 than in 2000.

The percentage of adults who spent most of their day sitting increased from 36.8% in 2000 to 39.9% in 2005. A similar increase was seen among both men and women, adults aged 25 years and over, and non-Hispanic white adults. Overall, the percentage of adults who spent most of their day standing or walking decreased between 2000 and 2005. A similar decrease was seen among adults aged 65 years and over and non-Hispanic white adults.

The percentage of adults who did no lifting during their usual daily activity increased from 28.3% in 2000 to 29.5% in 2005. An increase was also seen among adults aged 25–44 years and non-Hispanic white adults. The percentage of adults who lifted heavy loads during their usual daily activity decreased from 9.2% in 2000 to 7.6% in 2005. A similar decrease was seen among both men and women, adults aged 25–44 years and 45–64 years, Hispanic adults, non-Hispanic white adults, and non-Hispanic black adults.

The percentage of adults who engaged in no leisure-time physical activity increased from 38.5% in 2000 to 40.0% in 2005, and the percentage of adults who engaged in regular leisure-time physical activity decreased from 31.2% in 2000 to 29.7% in 2005. A similar pattern was seen among men and adults aged 25–44 years. The percentage of Hispanic adults who engaged in regular leisure-time physical activity also decreased, but the percentage who engaged in no leisure-time physical activity did not increase significantly.

The percentage of adults who were never active increased from 9.4% in 2000 to 10.3% in 2005. An increase was also seen among men, adults aged 25–44 years, and non-Hispanic white adults. The percentage of adults who engaged in a high level of physical activity decreased from 18.7% in 2000 to 16.7% in 2005. A similar decrease was seen among men, adults aged 25–44 years, Hispanic adults, non-Hispanic white adults, and non-Hispanic black adults.

Conclusions

While there was little change in the percentage of adults who engaged in usual daily activities and leisure-time physical activities between 2000 and 2005, the statistically significant changes that did occur indicate that U.S. adults are becoming less physically active. Between 2000 and 2005, there was an increase in the percentages of adults who spent their usual daily activity sitting, did not lift anything during their usual daily activity, and did not engage in any leisure-time physical activity. During this time period, the percentages of adults who walked during their usual daily activity, lifted heavy loads during their usual daily activity, and engaged in regular leisure-time physical activity decreased.

References

1. Myint PK, Luben RN, Wareham NJ, Welch AA, Bingham SA, Day NE, Khaw K. Combined work and leisure physical activity and risk of stroke in men and women in the European Prospective Investigation into Cancer in Norfolk prospective population study. Neuroepidemiology 27:122-9. 2006.
2. Borodulin K, Tuomilehto J, Peltonen M, Lakka TA, Sundvall J, Jousilahti P. Association of leisure time physical activity and abdominal obesity with fasting serum insulin and 2-h postchallenge plasma glucose levels. Diabet Med 23:1025-8. 2006.
3. Khaw K, Jakes R, Bingham S, Welch A, Luben R, Day N, Wareham N. Work and leisure time physical activity assessed using a simple, pragmatic, validated questionnaire and incident cardiovascular disease and all-cause mortality in men and women: The European Prospective Investigation into Cancer in Norfolk prospective population study. Int J Epidemiol 35(4):1034-43. 2006.
4. Kruger J, Blanck HM, Gillespie C. Dietary and physical activity behaviors among adults successful at weight loss maintenance. Int J Behav Nutr Phys Ac 3:17. 2006.
5. Research Triangle Institute. SUDAAN (Release 9.0.1) [Computer Software]. Research Triangle Park, NC: Research Triangle Institute. 2005.