Physical activity trends in South Carolina, 1994-2000.

Objectives: During the 1990s, physical activity recommendations and surveillance methods were developed in an attempt to increase and monitor, respectively, regular physical activity prevalence rates. For this article, Behavioral Risk Factor Surveillance System data were analyzed to determine whether regular physical activity proportions in South Carolina adults changed from 1994 to 2000. The physical activity prevalence rates for South Carolina were compared with national rates and Healthy People 2000 goals to measure progress. The rate of physical activity counseling by physicians and other health professionals was also analyzed from 1998 to 1999.

Methods: Total subjects included 10,495 adults ages 18 years and older from South Carolina and 545,445 from the remainder of the United States. Using random-digit dialing procedures in 1994, 1996, 1998 and 2000, the two most frequent types of leisure-time physical activity performed in the past month were identified. For activities listed, the frequency (days/wk) and duration (minutes/d) were obtained. Linear regressions were performed on regular physical activity and inactivity for the total population and by gender, race, age, and body mass index (BMI). Data pertaining to whether or not a physician or other health professional had provided physical activity counseling were also obtained for 1998 and 1999.

Results: From 1994 to 2000, the proportion of South Carolina adults participating in regular leisure time physical activity significantly increased (10.8%). Interestingly, the prevalence of regular physical activity in the rest of the nation remained unchanged during this time. Although significant increases were observed in nearly all subgroups, physical activity prevalence rates for South Carolina adults lagged behind national levels and did not meet Healthy People 2000 goals. Physical activity counseling by physicians and other health professionals increased from 1998 (24.1%) to 1999 (30.4%).

Conclusions: While it is not known what factors influenced regular physical activity from 1994 to 2000, they seem to have been equally effective in South Carolina adults of both genders, both races, regular and overweight status, and nearly all age groups. Despite these positive trends, additional efforts are needed to develop and implement effective community and primary care physical activity interventions that facilitate improvements among the nearly two-thirds of South Carolina adults who do not participate in sufficient physical activity to reap significant health benefits.

Key Words: behavior, physical activity, physician counseling, trends

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Physical inactivity has been linked to many chronic diseases such as diabetes, obesity, colon cancer, and cardiovascular disease. (1) Because physical activity has such a strong health impact, the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM) developed physical activity recommendations, which if followed, would produce significant health benefits. (2) Healthy People 2000: National Health Promotion and Disease Prevention Objectives (3) was created to give a national prevention strategy for improving the health of the American people. Healthy People 2000 had 22 priority areas and the first one listed was devoted to physical activity and fitness. Healthy People 2000 had three objectives to improve participation in physical activity nationally, which included: 1) increased participation in light-to-moderate physical activity to 30%; 2) increased participation in vigorous physical activity to 20%; and 3) decreased physical inactivity to 15%. (3)

From 1990 to 1998, the prevalence nationally of irregular physical activity participation increased slightly from 45.0% to 45.9%, while the prevalence of regular physical activity participation increased from 24.3% to 25.4%. (4) It has been estimated that during the period from 1994 to 1996, less than one-fifth of South Carolinians obtained sufficient amounts of leisure-time physical activity. (5) Approximately one-half were irregularly active, and nearly one-third completely sedentary. (5) In 1998, it was reported that high physical inactivity levels had persisted in South Carolina compared with the Southeast and the United States as a whole. (6)

Understanding the inverse association between physical activity and chronic diseases has led to the development of many recommendations and surveillance methods in an attempt to increase regular physical activity prevalence rates, and also to monitor physical activity rate changes. The Behavioral Risk Factor Surveillance System (BRFSS) is used at the national and state level to track risk behaviors associated with chronic disease. For this paper, BRFSS data were analyzed at the state level to determine if regular physical activity proportions in South Carolina and nationally have changed from 1994 to 2000. Data pertaining to physical activity counseling by physicians and other health professionals were also analyzed.

Materials and Methods

Data from 1994, 1996, 1998, and 2000 South Carolina BRFSS (SC BRFSS) and national BRFSS were analyzed for this study. The SC BRFSS was designed to assess the prevalence of behavioral risk factors associated with chronic disease, and is administered annually to a sample of state residents by telephone using random digit dialing procedures.

Subjects included 10,495 adults (men, n = 4,305; women, n = 6,190) aged 18 years and older from South Carolina and 545,445 (men, n = 223,698; women, n = 321,747) from the remainder of the United States. The two most frequent types of leisure time physical activity performed in the past month were identified, and for activities listed, the frequency (days/wk) and duration (minutes/d) were obtained. For analytic purposes, regular physical activity was classified as meeting the guidelines for moderate-intensity physical activity and/or vigorous-intensity physical activity. Those meeting moderate-intensity physical activity guidelines reported engaging in moderate-intensity activity 5 days per week for at least 30 minutes per day. Those meeting vigorous-intensity physical activity guidelines reported engaging in vigorous-intensity activity for at least 3 days per week for at least 20 minutes per day. Those reporting no physical activity were classified as inactive.

The prevalence of regular physical activity, moderate physical activity, vigorous physical activity, and inactivity were calculated for South Carolina adults from 1994 to 2000. For a comparison between South Carolina and the United States, national regular physical activity levels were also computed for each year. Regression analyses were performed to determine whether linear trends existed, while adjusting for any curvature in levels of regular physical activity among South Carolina adults from 1994 to 2000. Linear regressions were performed for the total population and by gender, race, age, and body mass index (BMI).

The 1998 and 1999 SC BRFSS included the following question: "Has a doctor or other health professional ever talked with you about physical activity or exercise?" The proportion of those reporting that they had received counseling within the past year was calculated. All regression and descriptive analyses were weighted using SAS-callable SUDAAN (Version 8.2, Research Triangle Institute, Cary, NC) statistical software to account for the complex sampling design.

Results

The Table shows the prevalence of adults in South Carolina who participated in regular physical activity by gender, race, age, and BMI from 1994 to 2000. Less than one-fourth of the total adult population in South Carolina was regularly active during these years. However, regular physical activity participation significantly increased over time for all but a few subgroups. For the total adult population, a 10.8% increase in the prevalence of regular physical activity was noted from 1994 to 2000. There were no significant changes in physical inactivity prevalence in the total adult population or any of the subgroups (data not shown).

Figure 1 displays the proportion of South Carolina adults who reported regular physical activity. From 1994 to 2000, the number of South Carolina adults participating in regular physical activity increased. However, the prevalence of regular physical activity in the rest of the United States remained unchanged. Furthermore, adults living in South Carolina participated less in regular physical activity than the US population over the same time period.

Figure 2 shows the trends from 1994 to 2000 in South Carolina adults for the prevalence of moderate-intensity physical activity, vigorous-intensity physical activity, and physical inactivity. The data indicate slight increases in the prevalence of moderate- and vigorous-intensity physical activity, and a relative stability of physical inactivity. In addition, significant gaps remain between the prevalence rates for South Carolina adults and Healthy People 2000 goals.

[FIGURE 1 OMITTED]

Responses on whether or not a doctor or other health professional ever talked to a respondent about physical activity or exercise were available for 1998 and 1999 only. The proportion of South Carolina adults reporting that they had received such counsel within the past year increased from 24.1% in 1998 to 30.4% in 1999. Those reporting that they had not received such advice decreased from 66.2% in 1998 to 57.2% in 1999.

Discussion

On a positive note, from 1994 to 2000 the proportion of South Carolina adults participating in regular physical activity significantly increased. In contrast, the prevalence of regular physical activity in the United States did not change during the years studied. Even though the prevalence of regular physical activity among South Carolina adults increased, the Healthy People 2000 goals for physical activity were not achieved, and the rates remained lower compared with the rest of the nation. It is unclear which factors may have contributed to the increase in regular physical activity in South Carolina. However, additional resources and efforts need to be devoted to promoting physical activity, considering the relatively low rates of South Carolina adults meeting recommended levels of physical activity (5-20%), and considering as well that one-third are physically inactive (ie, report no leisure-time physical activity in the past 30 days). In total, nearly two-thirds of all South Carolina adults are insufficiently active to reap significant health benefits.

Significant increases in regular physical activity were observed in all but three subgroups (it should be noted that these subgroups did experience nonsignificant increases). Though it is not known what factors influenced regular physical activity from 1994 to 2000, they seem to have been equally effective in South Carolina adults of both genders, both races, regular and overweight status, and nearly all age groups. Following the release of the Surgeon General's Report on Physical Activity and Health in 1996, (1) there has been an increase in the awareness of the important role physical activity has in attaining and maintaining good health. Since that time, considerable media attention has also been given to the dramatic rises in rates of obesity and type 2 diabetes, and the association of these with physical inactivity. The increased public focus on these issues may be partially responsible for the increase in physical activity. It is incumbent upon healthcare and public health researchers to engage in additional studies to identify the primary determinants of physical activity for various subgroups so that effective interventions can be implemented in a variety of settings.

[FIGURE 2 OMITTED]

Typically, physicians' care is at the secondary and tertiary levels of treatment. However, because they have contact with people on a daily basis, they can be very effective in primary prevention through physical activity counseling. Many studies have reported that when physicians provide physical activity counseling to their patients, those people have higher physical activity levels compared with those who did not receive physician-based physical activity counseling. (7,8) The present study noted a positive trend in South Carolina adults receiving physician counseling about physical activity within the past year. Adults reporting that they received physical activity counsel from their physician or other health professional increased from 24.2% in 1998 to 30.4% in 1999. Unfortunately, these data were not gathered during other years when physical activity data were obtained. Thus, a trend analysis could not be performed, and the relationship between rates of physical activity counseling and rates of physical activity could not be explored in more detail.

Although there was a substantial increase in adults receiving physical activity counseling from their doctor and other health professionals, a large proportion of South Carolina adults (57.2%-66.2%) still reported not receiving such advice. As a result, opportunities to facilitate behavior change were missed. Doctors, other health professionals, public health experts, health care administrators, and health insurers need to employ cost-effective and efficient ways to provide physical activity counseling to patients. This is a vital area of consideration since several studies have documented the effectiveness of using brief physician counseling to increase physical activity in patients. (1,8,9)

Conclusions

The proportion of South Carolina adults participating in regular physical activity significantly increased from 1994 to 2000. The prevalence of physicians and other health professionals providing physical activity counseling to patients increased from 1998 to 1999. The increase in public awareness of the health benefits of physical activity and physician counseling may be partially responsible for the improved rates of physical activity in South Carolina adults. Despite these positive trends, the rates of regular physical activity among South Carolina adults lagged behind national rates and Healthy People 2000 goals. Additional efforts to develop and implement effective community and primary care physical activity interventions are needed to facilitate improvements among the nearly two-thirds of South Carolina adults who do not undertake sufficient physical activity to reap significant health benefits.

I Only two things are infinite, the universe and human stupidity, and
I'm not sure about the former.
--Albert Einstein

Table. Prevalence of regular physical activity by gender, race, age, and
body mass index among South Carolina adults

                     N (a)  1994 (b)  1996  1998  2000  Overall
                                                        Increase, %

Gender
  Men                4,305  20.5      21.3  23.3  26.2   9.6 (c)
  Women              6,190  17.0      16.9  20.4  23.9  12.0 (c)
Race
  Black               2299  12.2      16.9  19.3  19.6  12.3 (d)
  White               7813  20.8      19.9  22.6  27.4  11.3 (d)
Age (years)
  18-24               1035  24.4      24.5  26.0  29.0   7.7
  25-34               2115  20.1      18.5  27.0  26.5  13.8 (c)
  35-44               2297  19.0      16.6  18.3  24.4   8.9 (c,d)
  45-54               1936  17.7      16.8  17.8  22.2   7.9
  55-64               1371  18.0      20.0  19.1  26.0  11.5 (c)
  >64                 1741  12.1      19.5  22.3  22.9  17.6 (c)
Body Mass Index (e)
  Normal              4491  22.1      20.0  24.3  29.4  13.1 (c,d)
  Overweight          3557  17.9      19.5  22.1  26.1  13.5 (c)
  Obese               1962  13.1      17.3  16.1  17.8   6.3
Total population     10495  18.7      19.0  21.7  25.0  10.8 (c)

(a) Unweighted sample size for combined years.
(b) Percent weighted to state population (see Methods section for
definitions of activity levels).
(c) P value < 0.05.
(d) At least one point does not fit on a straight line.
(e) Normal = <25 kg/[m.sup.2]; Overweight = 25-29.9 kg/[m.sup.2], Obese
[greater than or equal to] 29.9 kg/[m.sup.2]

Acknowledgments

The authors wish to thank Dr. Cheryl Addy and Brent Hutto for their assistance with statistical analyses.

Accepted February 5, 2004.

References

1. US Department of Health and Human Services. Physical Activity and Health: A Report of the Surgeon General. Atlanta, US Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, 1996.

2. Pate RR, Pratt M, Blair SN, et al. Physical activity and public health: a recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. JAMA 1995;273:402-407.

3. US Department of Health and Human Services. Healthy People 2000: National health promotion and disease prevention objectives. Washington D.C., Public Health Services, 1991.

4. Centers for Disease Control and Prevention. Physical activity trends--United States, 1990-1998. MMWR 2001;50:166-169.

5. Ainsworth BE, Ransdell LB, Whitt MC, et al. Promoting physical activity among irregularly active South Carolinians: BRFSS 1994-1996. J S C Med Assoc 1999;95:257-261.

6. LaMonte MJ, Nahas MV, Neff LJ, et al. Trends in physical activity levels among black and white adults in South Carolina. J S C Med Assoc 2000;96:416-420.

7. Granner ML, Ligouri G, Kirkner GJ, et al. Health care provider counseling for physical activity among black and white South Carolinians. J S C Med Assoc 2001;97:338-341.

8. The Writing Group for the Activity Counseling Trial Research Group. Effects of physical activity counseling in primary care settings. JAMA 2001;286:677-687.

9. Centers for Disease Control and Prevention. Prevalence of health-care providers asking older adults about their physical activity levels--United States, 1998. MMWR 2002;51:412-414.

RELATED ARTICLE: Key Points

* A significant increase in the prevalence of regular physical activity among South Carolina adults was observed from 1994 to 2000. The increase was observed in adults of both genders, white and black race, healthy weight and overweight status, and varying age groups.

* The proportion of physicians and other health professionals providing physical activity counseling increased from 1998 to 1999.

* Despite positive trends in regular physical activity and physician counseling, nearly two-thirds of South Carolina adults do not participate in sufficient physical activity to gain significant health benefits.

Katrina D. DuBose, PHD, Karen A. Kirtland, PHD, Steven P. Hooker, PHD, and Regina M. Fields, MS

From the Energy Balance Laboratory, Schiefelbusch Institute for Lifespan Studies, University of Kansas. Lawrence, KS, and the Prevention Research Center and the Department of Exercise Science, Norman J. Arnold School of Public Health, University of South Carolina, Columbia SC.

This project was supported by a grant from the Centers for Disease Control and Prevention cooperative agreement U48/CCU409664-06.

Reprint requests to Steven P. Hooker, PhD, Prevention Research Center, 730 Devine Street, University of South Carolina, Columbia, SC 29208. Email: [e-mail]