Perceived environmental physical activity correlates among Asian Pacific Islander Americans

Journal of Physical Activity and Health, 2012, 9, 1098-1104 © 2012 Human Kinetics, Inc.

Perceived Environmental Physical Activity Correlates Among Asian Pacific Islander Americans Timothy J. Bungum, Merrill Landers, Maria Azzarelli, and Sheniz Moonie Background: Little is known about correlates of pbysical activity of Asian and Asian-Pacific Islander Americans (AAPI). Knowledge of these correlates could be useful in promoting physical activity. Purpose: to identify demographic and environmental correlates of physical activity among AAPI. Methods: Participants resided in the Las Vegas, Nevada area, and completed a 52-item telephone administered questionnaire that assessed physical activity behavior, environmental supports for physical activity and demographic factors. Environmental factors included the presence of neighborhood sidewalks, park availability, and nearby grocery stores were combined to create the variable "environmental pbysical activity supports" (EPAS). Neighborhood crime, pleasantness of tbe neigbborhood for walking, and the presence of loose dogs combined to form "neigbborhood safety." Logistic regression was used to identify predictors of physical activity. Potential predictors included age, gender, BMI, employment, educational attainment, neighborhood safety, and EPAS. Results: 263 respondents completed the survey. With the exception of living near a grocery store, respondents reported residing in neighborhoods that are generally supportive of physical activity. However, EPAS was the sole significant predictor of physical activity behavior (OR = 1.52, CI = 1.06-2.17). Age and educational attainment unexpectedly failed to predict physical activity. Conclusions: Supportive physical activity environments associate with physical activity behavior among AAPI. Keywords: Asian Americans, environmental correlates Physical activity is an important public bealtb bebavior because of the numerous disease preventing benefits associated with it.'-^ Prevalent diseases that are known to be prevented by pbysical activity include coronary heart disease, osteoporosis, and diabetes.^ Engaging in pbysical activity also aids in the reduction and prevention of the accumulation of excess body fat.^ This is an especially important area for public health autborities to address because substantial increases in obesity rates bave recently been observed among Americans."* An expressed goal of public health is to eliminate health disparities across ethnicities.' Contrary to the desires of public health experts, data indicate that ethnic disparities in physical activity exist. Minority group members bave consistently been shown to be less active than white Americans^'^ However, little is known about the physical activity habits of some minority groups, including AAPI.'-^ Therefore, physical activity characteristics of this group merit study.

Bungum is with the Dept of Epidemiology and Biostatistics, University of Nevada-Las Vegas. Landers is with the Dept of Physical Therapy, University of Nevada-Las Vegas. Azzarelli is with Dept of Chronic Disease Prevention and Health Promotion, Southern Nevada Health District, Las Vegas, NV. Moonie is with the Dept of Epidemiology and Biostatistics, University of Nevada-Las Vegas.

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It is also important to study AAPI because they are a minority group unlikely to engage in exercise, and are more opposed to engaging in physical activity than are whites or African Americans.^ Further, AAPI are an important ethnic group from a public health perspective because of tbeir large numbers. There are currently over 13 million, and tbeir proportion of tbe American population is increasing. Estimates indicate that by 2050,8% of the US population will be of AAPI descent.'° Thus, it is not surprising that the need to study the health bebaviors, and especially physical activity, among this subpopulation bas been expressed in the literature.*' A first step to understanding the physical activity behavior of members of ethnic subpopulations is to identify tbe bebavioral correlates of the bebavior (physical activity)." Physical activity correlates have typically been divided into 4 categories: demographic, psychological, social/cultural, and environmental.'^'^ It has long been known tbat pbysical activity correlates witb select psychosocial and demographic variables.'^ However, most studies tbat bave assessed tbese variables have explained less than 20% of the variance in physical activity.'"* The limited explanatory power of statistical models that predict pbysical activity bebavior is recognized, and it is believed that the inclusion of environmental factors may enhance researchers abilities to explain physical activity.'^ Because little work has been done tbat assesses the association of environmental factors with physical

Perceived Environmental Correlates Among Asians

activity behavior among AAPI, the purpose of this study was to investigate that relationship. Such information could be used by public health officials and urban planners to enhance the physical activity of AAPI.

Methods A telephone survey using random digit dialing was employed that targeted AAPI aged 18 years and older living in the Las Vegas, Nevada area. Phone calls were made from a university-based center by trained interviewers. Calls were made to zip code areas that have relatively high proportions, greater than 3%, of AAPI.'^ There are approximately 158,000 AAPI living in the Las Vegas area, Vi/hich is about 8.3% ofthe region's population." Calls were placed Mondays through Fridays from 10:00 AM to 7:00 PM These telephone contacts occurred from early March to mid-June of 2008. If the person answering the phone indicated that there were adult AAPI living in the residence, it was requested that the person who was at least 18 years of age, at home at the time of the call, and had most recently celebrated his or her birthday respond to questions regarding their physical activity and nutritional practices. The interviewer explained that a survey assessing health-related behaviors of AAPI was being conducted. Respondents were also informed that the interview would take about 10 minutes. Potential participants were also told of the study procedures and were provided with information about the investigation. Only 1 person per phone number was questioned and a maximum of 3 attempts per phone number were made. All interviews were conducted in English. The instrument used was a 52-item questionnaire that had been approved for use by the university's Institutional Review Board. Respondents were asked to report their current physical activity by selecting I of 8 statements that they believed best described their recent physical activity behavior. The choices were 1) no regular walking or physical activity and no intention to begin in the near future; 2) do not exercise or walk regularly but have been thinking of starting; 3) trying to start to exercise or walk, but such activity is infrequent; 4) participating in vigorous physical activity less than 3 times per week or moderate physical activity less than 5 times per week; 5) moderate physical activity at least 5 times per week, at least 30 minutes per bout, for 1 to 6 months ; 6) moderate physical activity, at least 30 minutes per bout, 5 or more times per week for 7 or more months; 7) vigorous physical activity 3 to 5 times per week, at least 20 minutes per bout for 1 to 6 months; or 8) vigorous physical activity at least 20 minutes per bout, 3 to 5 days per week for 7 or more months. This physical activity assessment tool has been validated.'^ Respondent physical activity levels were then categorized as "inactive" or "active." Those selecting choices numbered 1 or 2 were classified as "inactive." Because physical activity behavior tends to be overestimated,"

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participants selecting response number 3 ("trying to be physically active, but that such physical activity is infrequent") were also labeled as being "inactive." Respondents who described their physical activity behavior by selecting choices 4, 5, 6, 7, or 8 were labeled as "active." We believe that this physical activity grouping is justified because health benefits are hypothesized to occur even when physical activity is performed relatively infrequently and at low intensities.^° Neighborhood environments were assessed by 8 items. These specific items were selected because they have been shown to, or hypothesized to, influence physical activity.^' Specific items assessed the presence of neighborhood sidewalks, the nearness of parks and recreation facilities, the perceived prevalence of neighborhood crime, heaviness of neighborhood motorized traffic, whether neighbors could be trusted, the presence of unleashed dogs, overall neighborhood pleasantness, and the perception that a grocery store was within walking distance of their residences. Response choices to the items that assessed the availability of sidewalks and public recreation facilities, the trustworthiness of neighbors and the ability to easily walk to a grocery store were "yes" or "no." Items that measured the pleasantness ofthe neighborhood, the presence of unleashed dogs, and neighborhood crime were measured on 4-point Likert type scales. These items had endpoints of "not at all pleasant/very pleasant; not a problem at all/a problem; and not at all safe from crime, and extremely safe from crime," respectively. Items that were measured on 4-point scales were dichotomized. For instance, when measuring neighborhood pleasantness, "not at all pleasant" and "not pleasant" were combined, as were "pleasant" and "very pleasant." Respondents selected "heavy, moderate or light" to describe neighborhood traffic. Test-retest reliability of these scales have been assessed by others and have been found to be between .42 and .74.^^ Information regarding age, gender, and educational attainment were also collected, as these factors have been shown to influence physical activity.'^•"•^'' Educational attainment was dichotomized into 2 groups: those who had graduated from college, and those who had not. Items assessing dietary habits were not used in this study. Preliminary statistics were run to provide descriptions of the respondent's demographic characteristics. To assess the construct validity of the neighborhood environmental characteristics factor analysis was used. Items whose factor loading scores were > .40 were kept in the model.^5 Two components, using principal component analysis, were extracted. Three items (perceived crime, neighborhood pleasantness as a place to walk, and the heaviness of motorized traffic) were loaded on the component "neighborhood safety." Factors that loaded on the other component, "environmental physical activity supports" (EPAS), included the presence of sidewalks, the nearness of recreation areas, [including parks], and a nearby grocery store. The trustworthiness of neighbors, and whether loose dogs were a problem

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demographic variables for the sample are presented in Table 2. As can be seen, the mean age was 49.11± 17.9 years, 65.4% were females, and a relatively large proportion of subjects (47.1%) were college graduates. Approximately one-third of the sample reported their health to be very good or excellent. The average body mass index, 24.7 ± 4.85, was in the upper portion of the normal range."* A breakdown of current physical activity levels are presented in Table 3. Fifty-seven percent (n = 150) of respondents were classified as active. The variables that measured the neighborhood environment are listed in Table 4. With the exception of living near a grocery store, these neighborhood perceptions suggest support of physical activity. Results of the logistic regression equation are presented in Table 5. The sole significant predictor of physical activity behavior was EPAS. The statistical model explained 7.0% of the variance in physical activity.

in the neighborhood did not load at the > .40 threshold and therefore were not included in subsequent analyses. Finally, multiple logistic regression was used to identify predictors of being assigned to the physical activity groups (inactive or active). Variables entered in the regression models included neighborhood safety, EPAS, body mass index, marital status, educational attainment, employment status, gender, and age. The significance level for all analyses was set at P < .05.

Results A total of 263 Asian-American adults completed the questionnaire. As can be seen in Table 1, a plurality (27.8%) of respondents were of Chinese descent. Study participants of Japanese, Filipino, and Korean descent comprised 20.5, 14.8, and 11.8% of the sample, respectively. Other

Table 1 Sample Ethnicities Percent

Ethnicity

Chinese

27.8

73

Japanese

20.5

54

Filipino

14.8

39

Korean

11.8

31

Hawaiian

5.7

15

Vietnamese

4.9

13

Taiwanese

4.2

II

Thai

1.11

3

Cambodian

0.76

2

Guamanian

0.76

2

Samoan

0.76

2

Indonesian

0,38

1

Laotian

0.30

I

Other

6.08

16

Total

100.00

263

Table 2

Demographic Variables

Variable

Age (mean, SD) Female (%, n) Health (good or excellent; %, n) BMI (mean, SD) Married "yes" (%, n) Employed "yes" (%, n) College graduate "yes" (%, n)

49.11,17.9 65,4, 172 34.0, 89 24,7, 4,85 35,7, 169 55.1, 145 47,1, 124

Perceived Environmental Correlates Among Asians

Table 3

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Reported Recent Physical Activity Behavior n/%

Do not exercise or walk and do not plan to in the near future

26 / 9.9

Do not exercise or walk regularly but have been thinking of starting

26 / 9.9

Trying to start to exercise or walk, but such activity is infrequent

61 / 23.2

Vigorous physical activity less than 3 times per week or moderate physical activity less than 5 times per week

.

47 / 17.9

Moderate physical activity at least 5 times per week, at least 30 minutes per bout, for 1-6 months

33 / 12.5

Moderate physical activity, at least 30minutes per bout, 5 or more times per week for 7 or more months

48 / 18.3

Vigorous physical activity 3-5 times per week, at least 20 minutes per bout for 1-6 months;

9 / 3.4

Vigorous physical activity at least 20 minutes per bout, 3-5 days per week for 7 or more months.

13/4.9

Table 4

Neighborhood Environmental Characteristics

Question How safe from crime do you consider your neighborhood to be? (extremely or quite safe)

78.3

206

Would you say that motorized traffic in your neighborhood is . . . (light or moderate)

89.4

235

Rate your neighborhood as a place to walk? (pleasant or very pleasant)

87.5

230

Can you easily walk to a grocery store?

36.5

96

Does neighborhood have sidewalks?

87.1

229

Does neighborhood have public rec facilities?

71.9

189

Would you say that most people in your neighborhood can be trusted?

73.0

182

For walking in your neighborhood, would you say that unattended dogs are . . . (not a problem at all)

71.9 71.9

189

Table 5

Predictors of Physical Activity Level (Inactive or Active) ß

OR

CI

Neighborhood safety EPAS

.137 .142

1.146

0.89-1,.47

.27

1.52

1.06-2.17

.02

BMI

.039

0.96

0.93-1.02

.96

Gender

.184

0.84

0.44-.1.6I

.55

Age

.002

1.02

.98-1.2

.85

Employed

.053

.984

0.46-1.93

.89

Married

.480

1.61

.75-3.45

.22

College graduate

.338

.713

0.30-1.39

.67

Note. /f2 = .07. Abbreviations: EPAS, environmental physical activity supports.

Discussion The most interesting finding of this study is that EAPS (nearby grocery stores; the presence of sidewalks, and public park facilities) was the sole significant predictor of assignment to the physically active group. This finding agrees with the work of others and suggests that

neighborhoods with physical activity supports are associated with physical activity^' behavior among AAPI. The 3 items that comprise EPAS are influenced by zoning and development policies.^^These policies, which were first used in the 1920s, determine how the built environments of neighborhoods evolve.'^ This finding suggests that interventions designed to increase physical

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activity among AAPI might include efforts that infiuence the policies that determine how neighborhoods are built. Residents of 1 state have taken action to do just that. The Commonwealth of Virginia has recently enacted laws addressing development which will potentially augment physical activity behavior. Specific modifications to Virginia law include directives for narrower residential streets, and road systems that better link residential areas with schools, shops and other residential areas. Such built environment characteristics are believed to enhance the walkability and bikability of neighborhoods." This new law was not passed without opposition from some developers and residents who believe that people want to live in poorly connected places (eg, cul-de-sacs) because of perceived safety benefits.^' Other components of EPAS, the presence of neighborhood grocery stores, sidewalks, and nearby parks are suggestive of mixed land use (MLU).^^ MLU is the juxtaposition of residential, commercial, industrial, office, institutional, or other land uses such as public parks.^^ MLU is also associated with high population densities, and highly connected street systems. Highly connected street systems are those that have high proportions of 4-way intersections.'^ The prevalence of this type of land use has decreased in the last 60 years, a change that coincides with a decrease in physical activity levels among Americans.'^ Resumption of MLU development policies could enhance the physical activity behavior of AAPI, but such changes will likely require political and community action. The data in Table 4 highlight the challenge in creating new opportunities for AAPI to participate in physical activity. With the exception of "a grocery store that can be easily walked to" (36.5%), all otber environmental variables are largely supportive of physical activity behavior. This suggests a "ceiling effect" in regards to the built environment. Nevertheless, because grocery stores are the most common destination for those who walk for utilitarian purposes^* there is an opportunity to change the built environment by adopting policies that allow for grocery stores to be built within walking distances of residences. It should be noted that walking to a grocery store is an example of utilitarian physical activity. This type of activity is done while performing activities of daily living. Promoting utilitarian physical activity is prudent because this type of physical activity allows for the completing of tasks of daily living, while the walker or bicyclist concurrently accrues pbysical activity benefits. Available data provides additional rationale for promoting utilitarian physical activity. Exercise, which is defined as "planned physical activity," has been promoted for over 3 decades with little improvement in physical activity at the population level.^' It is believed that if utilitarian physical activity is the natural choice to travel to grocery stores and worksites, etc., people are more likely to walk or bike to those places.^" This belief is supported by data that shows that residents of New York City, our city most densely populated, and most utilitarian physical activity

friendly,^^ engage in more utilitarian physical activity than people in other large cities. The longitudinal nature of this study allowed researchers to observe that those who moved from more, to less densely populated areas did less utilitarian physical activity and the converse (those moving from less, to more densely populated cities produced more utilitarian physical activity was also true.^' The presence of sidewalks and public recreation facilities were also assessed components of tbe EPAS in this study. Some researchers have argued that sidewalks are essential for physical activity, and that supportive environments are helpful to increase physical activity.^' Our data are in agreement with this sentiment and suggest that building places that have these environmental supports, including sidewalks and recreational facilities,^^ will enhance the physical activity among Asian Americans. It is also noteworthy that demographic factors such as age, gender and educational attainment, which are frequently strong predictors of physical activity,^'' failed to do so in this study. Thisfindingsuggests some interesting possibilities, one of which is the effect of culture. Others have hypothesized that culture has an important infiuence on physical activity,' the implication being that changing American culture, and norms, toward more walking and physical work at or near home, could increase physical activity rates^^ and perhaps reduce obesity rates among Americans. As with all studies the present one is not without limitations. These limitations include the self-reporting of physical activity bebavior, which is sometimes over reported." Our array of environmental factors is not comprehensive. It would also have been optimal to have measured and assessed psychosocial variables, which as previously stated, have been shown to correlate with exercise.^** This may have been an issue in this study, as only 7.0% of the variance in physical activity is explained by our model. However, while our model explains a relatively small percentage of physical activity behavior, it is not all that dissimilar to what is often found in studies of this type.''' Another possible reason for the small proportion of variance explanation in this study is that it has been hypothesized that environmental factors may not be highly predictive of physical activity among minority populations because of economic, and the previously mentioned cultural influences.-"--'''Further because the survey was conducted in English only it is possible that recent immigrants who have yet to master English and would presumably be more likely to adhere to their previous customs, were less inclined to participate in this study. Further, several Asian subgroups were included in the study and physical activity correlates may differ by these subgroups.^ Finally, the cross sectional study design precludes the possibility of making causal statements. Future research targeting Asian Americans should include psychosocial variables and target specific Asian subgroups. This research would ideally be done in the context of longitudinal studies. Researchers should also

Perceived Environmental Correlates Among Asians

be alert for opportunities to conduct natural experiments to assess potential environmental infiuences of pbysical activity wben environments cbange. Such opportunities may soon be available in places sucb as Virginia wbere new laws are cbanging how our cities evolve. Acknowledgments The authors thank the Southern Nevada Health District for funding this research.

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