511546 research-article2013
WJN36610.1177/0193945913511546Yeom and Fleury
Intervention Studies
A Motivational Physical Activity Intervention for Improving Mobility in Older Korean Americans
Western Journal of Nursing Research 2014, Vol. 36(6) 713–731 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0193945913511546 wjn.sagepub.com
Hye-A Yeom1,2 and Julie Fleury2
Abstract There has been limited empirical support for interventions designed to promote physical activity targeting mobility in racially diverse older adults. This study aims to examine the effects of a Motivational Physical Activity Intervention (MPAI) on social resource, behavioral change process, physical activity, and mobility variables in sedentary older Korean Americans. A quasi-experimental, repeated-measure, pre- and post-tests design was used. Sixty-four community-dwelling, sedentary older Korean Americans (n = 33 for MPAI group, n = 31 for Attention Control group) participated in the study. There were significant improvements in social resources, including social support from family and friends; behavioral change process variables, including self-efficacy; motivational appraisal; and self-regulation for physical activity. There were significant intervention effects on physical activity, walking endurance, and flexibility. The MPAI is supported as improving mobility and physical activity, as well as increasing motivation for physical activity in older Korean Americans. Keywords mobility, Asian, exercise
1The
Catholic University of Korea, Seoul, Korea State University, Phoenix, USA
2Arizona
Corresponding Author: Hye-A Yeom, Assistant Professor, The Catholic University of Korea College of Nursing, 222 Banpo-daero, Seocho-gu, Seoul, 137-701, Korea. Email: [email protected]
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Impaired mobility is experienced as a limitation in independent physical movement, and is associated with a loss of independence, decreased quality of life, increased chance of institutionalization, and higher risk for mortality in older adults (Hirvensalo, Rantanen, & Heikkinen, 2000; Netuveli, Wiggins, Hildon, Montgomery, & Blane, 2006; von Bonsdorff, Rantanen, Laukkanen, Suutama, & Heikkinen, 2006). Forty-four percent of community-dwelling older adults report some type of impairment in mobility, the majority for longer than 1 year (Iezzoni, McCarthy, Davis, & Siebens, 2000; ShumwayCook, Ciol, Yorkston, Hoffman, & Chan, 2005). As the population ages, physical activity consistent with improved walking ability, balance, and flexibility is increasingly important for intact mobility and independence. Korean Americans are one of the fastest growing Asian populations in the United States, representing the fifth largest subgroup (U.S. Census Bureau, 2010). Older Korean Americans have lower levels of physical activity compared with Korean elderly living in Korea (Sohng & Lee, 2000), and lower rates of engaging in physical activity (34.4%) compared with White (80.8%) and Black (81%) older adults (Kim, Ahn, Chon, Bowen, & Khan, 2005). Descriptive studies conducted with older Korean Americans indicate that risk factors for impaired mobility include a lack of physical activity, social isolation, low levels of motivation, and lack of access to needed culturally relevant resources (Belza et al., 2004; Sin, LoGerfo, Belza, & Cunningham, 2004; Sohng, Sohng, & Yeom, 2002). The need for culturally relevant, community-based interventions has also been emphasized as a key public health strategy to meet the health needs of Korean American groups in the United States (Han, Kang, Kim, Ryu, & Kim, 2007). Suggested approaches for health-promotion interventions among Korean ethnic groups include participation of bilingual, bicultural researchers, partnership with cultural community advocates, and attention to settings of cultural and emotional support (Kim, Cho, Cheon-Klessig, Gerace, & Camilleri, 2002; Sin et al., 2004). Researchers have also suggested that more primary intervention studies are needed to increase knowledge on strategies for improving physical activity behaviors (Conn, Hafdahl, Brown, & Brown, 2008). Furthermore, intervention research is needed to address motivation for physical activity among older Korean Americans, a minority group at high risk for limited levels of physical activity (Lim, Kayser-Jones, & Waters, 2007; Lim, Waters, Froelicher, & Kayser-Jones, 2008).
Purpose The purpose of this study was to provide an initial test of the effectiveness of a theory-based intervention designed to promote motivation for
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Intervention (MPAI) - Empowering education - Motivational support - Social support - Mobility training
Increased motivation for regular physical activity - Self-efficacy - Motivation appraisal - Self-regulation
Improved mobility - Initiation of regular physical activity - Walking endurance - Balance - Flexibility - Walking speed
Figure 1. Wellness Motivation Theory.
moderate-intensity physical activity consistent with mobility in older Korean Americans using a culturally relevant approach. Study aims included evaluating the effects of a Motivational Physical Activity Intervention (MPAI) on social resource, behavioral change process, physical activity, and mobility variables in sedentary older Korean Americans.
Theoretical Framework The Wellness Motivation Theory (WMT; Fleury & Perez, 2009) provided the theoretical framework for MPAI development and testing. The WMT was relevant as a guide to promote motivation for moderate-intensity physical activity in older Korean Americans, as the theory interprets behavioral change processes and outcomes within a cultural context. The MPAI, including physical activity training (i.e., walking, balance, and flexibility training) and motivational content (social support, empowering education, motivational education) incorporating a culturally relevant perspective, was expected to result in improvements in social resource and behavioral change process variables, leading to increased physical activity and improved mobility in older Korean Americans (Figure 1).
Method Design and Sample A quasi-experimental, repeated-measure, pre- and post-tests design was used. The study design had one between-subjects treatment factor (MPAI vs. Attention Control group), and one within-subjects time factor (Time 1, Time 2). Measurement of social resource, behavioral change process, physical activity, and mobility variables occurred at Time 1 (T1; baseline assessment) and Time 2 (T2; 13 weeks following program initiation).
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Sixty-four community-dwelling older Korean Americans (n = 33 for MPAI group, n = 31 for Attention Control group) participated in the study. The sample size was determined based on an alpha level of .05 and a general rule of 30 as the minimum for each group in a theory-based pilot, intervention study (Sidani & Braden, 1998). Participants were Korean Americans aged 60 and above; residing in the metropolitan city area for more than 6 months, a period that distinguishes between a temporary visitor and a long-term resident; currently sedentary, evaluated using the Stages of Change questionnaire (pre-contemplation, contemplation, and preparation stage; Marcus et al., 2000); able to communicate in Korean or English; having intact cognition with a score of 24 or above on the Mini Mental State Examination–K (Park & Kwon, 1990); at low risk for participation in moderate-intensity physical activity as indicated by the Physical Activity Readiness Questionnaire (Thomas, Reading, & Shephard, 1992). Participants reported being free of comorbid conditions which required the use of ambulatory assist devices. We obtained no medical clearance from primary physicians.
Recruitment and Retention On Institutional Review Board approval for human subjects protection, participants were recruited for the intervention group through local ethnic media and newspapers. Recruitment letters and flyers, written in English and Korean, were also posted in Korean groceries in local area. Men and women were invited to participate in the study, and were asked to contact the investigator if they were interested in learning more about the study. Those expressing an interest in participating were screened for eligibility, and informed consent in English or Korean was obtained from those eligible to participate. The first 32 participants were recruited and assigned to the intervention group. Then, control group participants were recruited from two local churches. Random assignment could not be achieved due to entangled networks among older Korean Americans in the local community and possible contaminations among participants. Instead, those in the control group who had heard about the intervention program from their friends or family were placed in a waiting group for the second round of physical activity programs in the future. Recruitment and retention procedures incorporated culturally relevant strategies including personal contact between participants and the bilingual investigator through invitation/reminder phone calls, emphasis on the potential benefits of study participation to others, and an accepting atmosphere through respectful interaction (Lim et al., 2008). To facilitate continued participation in the study, the frequency, duration, and extent of
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expected participation were clearly communicated. MPAI and Attention Control participants were contacted by Korean-speaking research assistants through telephone and mail to remind them of the scheduled data collection times. Two research assistants helped with data collection for this study; one for the intervention group and the other for the control group. Each participant received two official contacts from the research team: at baseline and at post-intervention. During the intervention period, participants and researchers had need-based communications; participants made calls only when they had issues regarding the study participation process, including moving location, acute physical illness, or declining interest in further participation. All participants were compensated with a $10 (USD) gift card at each measurement time point.
Intervention Procedure and Structure The intervention program was culturally relevant because it included bilingual and bicultural researchers, built partnerships with cultural community advocates, and paid attention to the settings of cultural and emotional support. The MPAI participants received a 12-week intervention, while the Attention Control participants received biweekly newsletters over the same time period, focusing on older adult health and general issues, such as healthy nutrition, stress management, oral health, home safety, language issues, and interpersonal relationships. The intervention group did not receive these letters. Participants in the control group received no information or support specifically to increase physical activity during the intervention period. The MPAI consisted of 1-hr sessions held twice a week for 12 weeks. Program length was consistent with feasible and effective physical activity interventions in older adults (Yeom, Keller, & Fleury, 2009). The MPAI took place during the times when most participants could attend. Intervention sessions were held in conference rooms at a local Salvation Army Church. MPAI critical inputs included (a) physical activity training, including 10-min warm up using flexibility exercises, 10-min balance training, and 20-min moderateintensity walking; (b) social support operationalized through group process, goal setting, and interaction; (c) empowering education focusing on the creation of social contextual resources; and (d) motivational support for enhancing motivational appraisal and skills to initiate and sustain regular physical activity. In this study, group walking training was used as a critical component of motivational strategies, providing participants with a chance to experience physical activity and stimulating their intentions to adopt regular physical activity, which was the primary behavioral change of interest. The sequence of
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MPAI sessions included small to large muscle group exercise, single-joint to multiple-joint exercises, and low intensity to higher intensity exercises (American College of Sports Medicine [ACSM], 2002). The intervention took place in the conference room of the Salvation Army church during the morning, when most participants could attend. Intervention sessions were held in groups of approximately eight older adults. There was no specific instruction related to home practice. Social network support was designed to build and maintain social resources central to motivation for physical activity. A group format was used for the MPAI, as social support occurs within a common context to anticipate, interpret, and respond to others’ needs, consistent with cultural perspectives of collectivism and interpersonal exchange. Empowering education was used to develop skills needed to identify and develop resources to promote regular physical activity and mobility, including individual, behavioral, and environmental resources. Consistent with cultural perspectives acknowledging the interaction between person and environment, participants were encouraged to develop individual and community-level strategies and resources to promote physical activity and mobility. Motivational support develops motivation and skills to adopt and maintain physical activity consistent with personal goals related to intact mobility. Consistent with cultural perspectives acknowledging personal growth, knowledge, and self-regulation, motivational appraisal strategies included exploration of personal goals related to mobility, strategy formation with anticipatory problem solving to manage current or expected barriers to engaging in physical activity, and monitoring and regulating mobility activities (Lim et al., 2008). The MPAI was delivered by the researcher and a bilingual research assistant trained in the intervention protocol, to address language barriers and foster a sense of community in intervention delivery (Kim et al., 2002; Sin et al., 2004). The researcher was an advanced practice nurse and a university faculty who had previous experiences of holding physical activity programs for older Korean Americans in other regions of the United States in the past.
Measurement Measurement of variables occurred at baseline (T1), and at post-intervention (13 weeks, T2) through standardized questionnaires and objective measures of mobility. Data collection took place either in the home or Salvation Army Church; testing procedures were analogous for the MPAI and Attention Control groups. Participants were provided with verbal assistance in completing measures as needed. All measures were available in English and Korean. All of the participants requested translation assistance to complete the questionnaire and asked that their interviews be held in Korean.
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Translation and back-translation of measures were conducted, including English-to-Korean translation by the researcher, back-translation by a bilingual Korean American nursing scholar, back-translation review, and cognitive debriefing to evaluate the conceptual equivalence of the translation and the level of comprehensibility of the scales, in accord with the suggested principles of translation process for measures (Wild et al., 2005). Demographic characteristics. Demographic characteristics included age, gender, years of schooling completed, marital status, employment, medical insurance status, and socioeconomic status, measured as monthly income. Medication use and the presence of comorbid conditions were evaluated using dichotomous yes–no responses. Social resource variables. Social resource variables included social support from family and friends. Social support was measured using the Social Support and Exercise Survey (SSES; Sallis, Grossman, Pinski, Patterson, & Nader, 1987). The SSES-Family and SSES-Friend scales consist of nine items each. Items are rated on scales of 1 to 6, with higher scores indicating greater levels of social support. The internal consistency reliability, measured using Cronbach’s alpha, was .99 at Times 1 and 2 for the SSES-Family, and .99 at Time 1 and .98 at Time 2 for the SSES-Friend. Behavioral change process variables. Behavioral change process variables included self-efficacy, motivational appraisal, and self-regulation. Self-efficacy was measured using the Self-Efficacy for Exercise Scale (SES; Resnick & Jenkins, 2000). The SES consists of 9 items with dichotomous responses, with “yes” scores as 1 and “no” scores as 0. A higher sum score indicated greater self-efficacy for exercise. Cronbach’s alpha reliability was .93 at Time 1 and .88 at Time 2. Motivation appraisal, the construction of intention to initiate and maintain moderate-intensity physical activity, was measured using the Index of Readiness (IR; Fleury & Cameron-Go, 2003). The IR consists of nine items with responses ranging from 1 to 6, with a higher score indicating greater level of readiness to initiate and maintain physical activity. Cronbach’s alpha reliability of the IR was .87 at Time 1 and .93 at Time 2. Self-regulation in maintenance of physical activity was measured using the Index of Self-Regulation (ISR; Yeom, Fleury, Belyea, & Choi, 2011). The ISR consists of 9 items ranging from 1 to 6, with a higher score indicating greater self-regulation for physical activity. Cronbach’s alpha reliability of the ISR was .66 at Time 1 and .78 at Time 2 (Yeom & Fleury, 2011).
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Physical activity behavior. Physical activity behavior was measured using a single item, “Do you currently do any type of regular physical activity for a minimum of 30 min 3 times a week?” According to criteria proposed by the ACSM (Haskell et al., 2007), those who answered “yes” were categorized as engaging in regular physical activity. The validity of the ACSM criteria as measures for physical activity behaviors has been supported in the literature (Nelson et al., 2007; Pinto, Frierson, Rabin, Trunzo, & Marcus, 2005). Mobility. Using performance-based evaluations, mobility was measured in terms of walking endurance and physical performance, which included balance, gait velocity, and flexibility. Mobility levels were measured by the research team, which included the researcher and two research assistants. Each research assistant received individual training on measuring mobility and their measurement skills were tested for the first two cases they interviewed, resulting in 100% agreement between the researcher and the research assistants who record mobility levels. However, there was no interrater reliability measured between the outcome assessors in this study; thus, it should be measured in future studies. Walking endurance was measured using the 6-Minute Walk (6MW) test (Guyatt et al., 1985). The 6MW is a performance-based measure shown to be a valid indicator of mobility function (Bean et al., 2002). Participants were asked to walk as much as possible for 6 min; the number of meters walked was measured. Balance, flexibility, and gait velocity were measured using the Short Physical Performance Battery (SPPB; Guralnik et al., 1994), a performancebased mobility test. Balance was measured as number of seconds standing, by static balance tests including single-legged stance with the eyes open and closed. Flexibility was measured using the Chair Rise Method, which involves a bilateral knee extensor isokinetic peak index. Participants were asked to rise from a series of 6 chair heights ranging from 13 to 23 inches. The Chair Rise score was calculated as the lower height from which the participant could successfully rise without using their arms. Gait velocity was evaluated by asking participants to walk at their usual gait speed, calculating distance over 4 min. Each of the three domains was assigned a score ranging from 0 to 4, with 4 indicating the highest level, and 0 as inability to complete the test. The total SPPB score ranges from 0 to 12, with a higher score indicating better mobility function. The validity of the SPPB has been established (The LIFE Study Investigators, 2006; Ostir, Volpato, Fried, Chaves, & Guralnik, 2002).
Analysis Data analysis included descriptive statistics to characterize sample demographic characteristics, social resource, behavioral change process, physical Downloaded from wjn.sagepub.com at NORTH CAROLINA STATE UNIV on March 18, 2015
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activity, and mobility variables. Attendance and attrition rates, as well as reasons for attrition were evaluated using descriptive statistics. Repeated measures analysis of variance was conducted to examine the effects of the MPAI on social resource, behavioral change process, and mobility variables in sedentary older Korean Americans. A chi-square test was used to evaluate changes in physical activity behavior. The values of p ≤ .05 were considered statistically significant. There was no missing data for this study.
Results Demographic Characteristics Evaluation of homogeneity between MPAI and Attention Control participants resulted in no significant between-group differences in demographic characteristics (Table 1), social resources, behavioral change process variables, physical activity, or mobility at baseline (Table 2). The mean age of the total subjects was 71 years (SD = 7.44), with a range from 60 to 89 years. The mean age was 71 years (SD = 7.52) in the intervention group and 72 years (SD = 7.40) in the control group, showing no significant difference (t = .79; p = .433). The majority of participants were women (76.6%), retired (95.3%), and had medical insurance (92.2%). More than half of participants were living with a spouse or partner (59.4%). About one third of the participants (28.2%) were college graduates, and one third were high school graduates (34.4%). In terms of economic status, 41.2% reported having a monthly income of $1,001 to $3,000. The average duration of residency in the United States was 24 years, with a range from 1 year to 45 years. Participants reported having one or more comorbid conditions (n = 54; 84.4%) and taking medication (n = 54; 84.4%). The average participation rate was 92%; 3 participants in MPAI group withdrew due to admission to hospital or caregiving responsibilities. No adverse events were reported (Figure 2).
Behavioral Change Process and Social Resources Variables There were significant improvements in the social resource variable of social support from family and friends and behavioral change process variables of self-efficacy, motivational appraisal, and self-regulation (Table 3). Scores of MPAI participants increased significantly compared with Attention Control participants in social support from family (F = 21.87; p < .001) and friends (F = 24.72; p < .001), self-efficacy (F = 31.09; p < .001), motivational appraisal for physical activity (F = 79.16; p < .001), and self-regulation (F = 31.51; p < .001). Downloaded from wjn.sagepub.com at NORTH CAROLINA STATE UNIV on March 18, 2015
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Table 1. General Characteristics of Participants. General Characteristics Marital status Spouse Without spouse Gender Female Male Education Over college High school Middle school Less than middle school Job status Yes No Monthly income $0-$1,000 $1,001-$2,000 $2,001-$3,000 $3,001-$5,000 More than $5,000 Medical insurance Yes No Medication status Yes No Morbidity Yes No
Intervention (n = 33) n (%)
Control (n = 31) n (%)
20 (31.3) 13 (20.3)
Total (n = 64) n (%)
χ2
p
18 (28.1) 13 (20.3)
4.10
.393
38 (59.4) 26 (40.6)
23 (35.9) 10 (15.6)
26 (40.6) 5 (7.8)
1.79
.181
49 (76.6) 15 (23.4)
12 (18.7) 8 (12.5) 7 (10.9) 6 (9.4)
6 (9.4) 14 (21.9) 6 (9.4) 5 (7.8)
7.99
.157
18 (28.1) 22 (34.4) 13 (20.3) 11 (17.2)
2 (3.1) 31 (48.4)
1 (1.6) 30 (46.9)
0.29
.592
3 (4.7) 61 (95.3)
9 (14.1) 10 (15.6) 5 (7.8) 6 (9.4) 3 (4.7)
10 (15.6) 5 (7.8) 7 (10.9) 4 (6.3) 5 (7.8)
3.61
.608
19 (29.7) 15 (23.4) 12 (18.7) 10 (15.7) 8 (12.5)
30 (46.9) 3 (4.7)
29 (45.3) 2 (3.1)
0.15
.694
59 (92.2) 5 (7.8)
27 (42.2) 6 (9.4)
27 (42.2) 4 (6.3)
0.34
.561
54 (84.3) 10 (15.7)
27 (42.2) 6 (9.2)
27 (42.2) 4 (6.3)
0.34
.561
54 (84.3) 10 (15.7)
Regular Physical Activity Following the intervention, MPAI participants were more likely to engage in regular physical activity consistent with ACSM criteria compared with the Attention Control participants (χ2 = 25.01; p < .001).
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Yeom and Fleury Table 2. Baseline Characteristics of Participants. Intervention (n = 33) M ± SD
Control (n = 31) M ± SD
Residency in the 22.18 ± 12.26 26.39 ± 10.01 United States Motivational 2.72 ± 0.45 2.62 ± 0.61 appraisal Self-regulation 2.67 ± 0.84 2.52 ± 0.63 Self-efficacy 3.91 ± 3.82 4.16 ± 3.56 6MWT 213.00 ± 98.46 204.03 ± 88.55 SPPB 7.94 ± 2.19 8.87 ± 2.45
t
p
Total (n = 64) n (%) M ± SD
1.50
.139
24.48 ± 11.92
0.76
.451
2.67 ± 0.53
0.77 0.27 0.38 1.61
.447 .786 .704 .113
2.60 ± 0.75 4.03 ± 3.67 208.66 ± 93.16 8.39 ± 2.35
Note. 6MWT = 6-Minute Walk Test; SPPB = Short Physical Performance Battery.
Mobility 6MWT. MPAI participants improved significantly on the 6MWT compared with the Attention Control participants (F = 16.36; p < .001). The mean walk distance increased from 213 m at Time 1 to 251 m at Time 2 in MPAI participants, and decreased from 204 m at Time 1 to 196 m at Time 2 in Attention Control participants. Estimated effect size of the intervention on 6MWT was .59. SPPB. MPAI participants improved significantly on SPPB compared with Attention Control participants (F = 16.28; p < .001). Of SPPB subdomains, MPAI participants had greater increases in the domain of flexibility compared with Attention Control participants (F = 15.46; p < .001). There were no significant differences between the MPAI and Attention Control participants on balance or gait velocity scores (Table 3). Estimated effect size of the intervention on SPPB was .14.
Discussion This study provided initial support for the research question as to whether older Korean Americans receiving the MPAI would show significantly improved social resources, behavioral change processes, physical activity, and mobility over Attention Control participants. Researchers who implement physical activity programs with older Korean Americans may use this theory-based motivational approach focusing on community support
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Figure 2. Flow diagram for subject recruitment.
33 Included in analysis
3 excluded ▪ 2 withdrawn from acute physical illness ▪ 1 declined further participation
36 MPAI group ▪ 27 Salvation Army church members ▪ 9 non-church members
72 Included for participation
75 Screened for eligibility
31 Included in analysis
5 excluded ▪ 2 relocated to other cities ▪ 1 lost to contact ▪ 2 declined further participation
36 Attention Control group
3 excluded for not meeting inclusion criteria
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Table 3. Effects of MPAI on Walking Mobility, Physical Performance, Behavioral Change Process, and Social Resources Variables.
Variables 6MWT SPPB total SPPB-balance SPPB-walking speed SPPB-flexibility Self-regulation for physical activity Self-efficacy for physical activity Readiness for physical activity Social support from family Social support from friends
Control M ± SD
Group F (p)
Time Point Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test
213 ± 98.46 251 ± 110.67 7.94 ± 2.19 9.45 ± 1.82 3.58 ± 0.75 3.94 ± 0.35 2.24 ± 1.00 2.82 ± 0.92 2.15 ± 1.15 2.70 ± 1.13 2.67 ± 0.84 3.77 ± 0.38
204 ± 88.55 1.76 (.190) 7.29 (.009) 196 ± 92.91 8.87 ± 2.45 0.37 (.547) 32.40 (
WJN36610.1177/0193945913511546Yeom and Fleury
Intervention Studies
A Motivational Physical Activity Intervention for Improving Mobility in Older Korean Americans
Western Journal of Nursing Research 2014, Vol. 36(6) 713–731 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0193945913511546 wjn.sagepub.com
Hye-A Yeom1,2 and Julie Fleury2
Abstract There has been limited empirical support for interventions designed to promote physical activity targeting mobility in racially diverse older adults. This study aims to examine the effects of a Motivational Physical Activity Intervention (MPAI) on social resource, behavioral change process, physical activity, and mobility variables in sedentary older Korean Americans. A quasi-experimental, repeated-measure, pre- and post-tests design was used. Sixty-four community-dwelling, sedentary older Korean Americans (n = 33 for MPAI group, n = 31 for Attention Control group) participated in the study. There were significant improvements in social resources, including social support from family and friends; behavioral change process variables, including self-efficacy; motivational appraisal; and self-regulation for physical activity. There were significant intervention effects on physical activity, walking endurance, and flexibility. The MPAI is supported as improving mobility and physical activity, as well as increasing motivation for physical activity in older Korean Americans. Keywords mobility, Asian, exercise
1The
Catholic University of Korea, Seoul, Korea State University, Phoenix, USA
2Arizona
Corresponding Author: Hye-A Yeom, Assistant Professor, The Catholic University of Korea College of Nursing, 222 Banpo-daero, Seocho-gu, Seoul, 137-701, Korea. Email: [email protected]
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Impaired mobility is experienced as a limitation in independent physical movement, and is associated with a loss of independence, decreased quality of life, increased chance of institutionalization, and higher risk for mortality in older adults (Hirvensalo, Rantanen, & Heikkinen, 2000; Netuveli, Wiggins, Hildon, Montgomery, & Blane, 2006; von Bonsdorff, Rantanen, Laukkanen, Suutama, & Heikkinen, 2006). Forty-four percent of community-dwelling older adults report some type of impairment in mobility, the majority for longer than 1 year (Iezzoni, McCarthy, Davis, & Siebens, 2000; ShumwayCook, Ciol, Yorkston, Hoffman, & Chan, 2005). As the population ages, physical activity consistent with improved walking ability, balance, and flexibility is increasingly important for intact mobility and independence. Korean Americans are one of the fastest growing Asian populations in the United States, representing the fifth largest subgroup (U.S. Census Bureau, 2010). Older Korean Americans have lower levels of physical activity compared with Korean elderly living in Korea (Sohng & Lee, 2000), and lower rates of engaging in physical activity (34.4%) compared with White (80.8%) and Black (81%) older adults (Kim, Ahn, Chon, Bowen, & Khan, 2005). Descriptive studies conducted with older Korean Americans indicate that risk factors for impaired mobility include a lack of physical activity, social isolation, low levels of motivation, and lack of access to needed culturally relevant resources (Belza et al., 2004; Sin, LoGerfo, Belza, & Cunningham, 2004; Sohng, Sohng, & Yeom, 2002). The need for culturally relevant, community-based interventions has also been emphasized as a key public health strategy to meet the health needs of Korean American groups in the United States (Han, Kang, Kim, Ryu, & Kim, 2007). Suggested approaches for health-promotion interventions among Korean ethnic groups include participation of bilingual, bicultural researchers, partnership with cultural community advocates, and attention to settings of cultural and emotional support (Kim, Cho, Cheon-Klessig, Gerace, & Camilleri, 2002; Sin et al., 2004). Researchers have also suggested that more primary intervention studies are needed to increase knowledge on strategies for improving physical activity behaviors (Conn, Hafdahl, Brown, & Brown, 2008). Furthermore, intervention research is needed to address motivation for physical activity among older Korean Americans, a minority group at high risk for limited levels of physical activity (Lim, Kayser-Jones, & Waters, 2007; Lim, Waters, Froelicher, & Kayser-Jones, 2008).
Purpose The purpose of this study was to provide an initial test of the effectiveness of a theory-based intervention designed to promote motivation for
Downloaded from wjn.sagepub.com at NORTH CAROLINA STATE UNIV on March 18, 2015
715
Yeom and Fleury
Intervention (MPAI) - Empowering education - Motivational support - Social support - Mobility training
Increased motivation for regular physical activity - Self-efficacy - Motivation appraisal - Self-regulation
Improved mobility - Initiation of regular physical activity - Walking endurance - Balance - Flexibility - Walking speed
Figure 1. Wellness Motivation Theory.
moderate-intensity physical activity consistent with mobility in older Korean Americans using a culturally relevant approach. Study aims included evaluating the effects of a Motivational Physical Activity Intervention (MPAI) on social resource, behavioral change process, physical activity, and mobility variables in sedentary older Korean Americans.
Theoretical Framework The Wellness Motivation Theory (WMT; Fleury & Perez, 2009) provided the theoretical framework for MPAI development and testing. The WMT was relevant as a guide to promote motivation for moderate-intensity physical activity in older Korean Americans, as the theory interprets behavioral change processes and outcomes within a cultural context. The MPAI, including physical activity training (i.e., walking, balance, and flexibility training) and motivational content (social support, empowering education, motivational education) incorporating a culturally relevant perspective, was expected to result in improvements in social resource and behavioral change process variables, leading to increased physical activity and improved mobility in older Korean Americans (Figure 1).
Method Design and Sample A quasi-experimental, repeated-measure, pre- and post-tests design was used. The study design had one between-subjects treatment factor (MPAI vs. Attention Control group), and one within-subjects time factor (Time 1, Time 2). Measurement of social resource, behavioral change process, physical activity, and mobility variables occurred at Time 1 (T1; baseline assessment) and Time 2 (T2; 13 weeks following program initiation).
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Sixty-four community-dwelling older Korean Americans (n = 33 for MPAI group, n = 31 for Attention Control group) participated in the study. The sample size was determined based on an alpha level of .05 and a general rule of 30 as the minimum for each group in a theory-based pilot, intervention study (Sidani & Braden, 1998). Participants were Korean Americans aged 60 and above; residing in the metropolitan city area for more than 6 months, a period that distinguishes between a temporary visitor and a long-term resident; currently sedentary, evaluated using the Stages of Change questionnaire (pre-contemplation, contemplation, and preparation stage; Marcus et al., 2000); able to communicate in Korean or English; having intact cognition with a score of 24 or above on the Mini Mental State Examination–K (Park & Kwon, 1990); at low risk for participation in moderate-intensity physical activity as indicated by the Physical Activity Readiness Questionnaire (Thomas, Reading, & Shephard, 1992). Participants reported being free of comorbid conditions which required the use of ambulatory assist devices. We obtained no medical clearance from primary physicians.
Recruitment and Retention On Institutional Review Board approval for human subjects protection, participants were recruited for the intervention group through local ethnic media and newspapers. Recruitment letters and flyers, written in English and Korean, were also posted in Korean groceries in local area. Men and women were invited to participate in the study, and were asked to contact the investigator if they were interested in learning more about the study. Those expressing an interest in participating were screened for eligibility, and informed consent in English or Korean was obtained from those eligible to participate. The first 32 participants were recruited and assigned to the intervention group. Then, control group participants were recruited from two local churches. Random assignment could not be achieved due to entangled networks among older Korean Americans in the local community and possible contaminations among participants. Instead, those in the control group who had heard about the intervention program from their friends or family were placed in a waiting group for the second round of physical activity programs in the future. Recruitment and retention procedures incorporated culturally relevant strategies including personal contact between participants and the bilingual investigator through invitation/reminder phone calls, emphasis on the potential benefits of study participation to others, and an accepting atmosphere through respectful interaction (Lim et al., 2008). To facilitate continued participation in the study, the frequency, duration, and extent of
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expected participation were clearly communicated. MPAI and Attention Control participants were contacted by Korean-speaking research assistants through telephone and mail to remind them of the scheduled data collection times. Two research assistants helped with data collection for this study; one for the intervention group and the other for the control group. Each participant received two official contacts from the research team: at baseline and at post-intervention. During the intervention period, participants and researchers had need-based communications; participants made calls only when they had issues regarding the study participation process, including moving location, acute physical illness, or declining interest in further participation. All participants were compensated with a $10 (USD) gift card at each measurement time point.
Intervention Procedure and Structure The intervention program was culturally relevant because it included bilingual and bicultural researchers, built partnerships with cultural community advocates, and paid attention to the settings of cultural and emotional support. The MPAI participants received a 12-week intervention, while the Attention Control participants received biweekly newsletters over the same time period, focusing on older adult health and general issues, such as healthy nutrition, stress management, oral health, home safety, language issues, and interpersonal relationships. The intervention group did not receive these letters. Participants in the control group received no information or support specifically to increase physical activity during the intervention period. The MPAI consisted of 1-hr sessions held twice a week for 12 weeks. Program length was consistent with feasible and effective physical activity interventions in older adults (Yeom, Keller, & Fleury, 2009). The MPAI took place during the times when most participants could attend. Intervention sessions were held in conference rooms at a local Salvation Army Church. MPAI critical inputs included (a) physical activity training, including 10-min warm up using flexibility exercises, 10-min balance training, and 20-min moderateintensity walking; (b) social support operationalized through group process, goal setting, and interaction; (c) empowering education focusing on the creation of social contextual resources; and (d) motivational support for enhancing motivational appraisal and skills to initiate and sustain regular physical activity. In this study, group walking training was used as a critical component of motivational strategies, providing participants with a chance to experience physical activity and stimulating their intentions to adopt regular physical activity, which was the primary behavioral change of interest. The sequence of
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MPAI sessions included small to large muscle group exercise, single-joint to multiple-joint exercises, and low intensity to higher intensity exercises (American College of Sports Medicine [ACSM], 2002). The intervention took place in the conference room of the Salvation Army church during the morning, when most participants could attend. Intervention sessions were held in groups of approximately eight older adults. There was no specific instruction related to home practice. Social network support was designed to build and maintain social resources central to motivation for physical activity. A group format was used for the MPAI, as social support occurs within a common context to anticipate, interpret, and respond to others’ needs, consistent with cultural perspectives of collectivism and interpersonal exchange. Empowering education was used to develop skills needed to identify and develop resources to promote regular physical activity and mobility, including individual, behavioral, and environmental resources. Consistent with cultural perspectives acknowledging the interaction between person and environment, participants were encouraged to develop individual and community-level strategies and resources to promote physical activity and mobility. Motivational support develops motivation and skills to adopt and maintain physical activity consistent with personal goals related to intact mobility. Consistent with cultural perspectives acknowledging personal growth, knowledge, and self-regulation, motivational appraisal strategies included exploration of personal goals related to mobility, strategy formation with anticipatory problem solving to manage current or expected barriers to engaging in physical activity, and monitoring and regulating mobility activities (Lim et al., 2008). The MPAI was delivered by the researcher and a bilingual research assistant trained in the intervention protocol, to address language barriers and foster a sense of community in intervention delivery (Kim et al., 2002; Sin et al., 2004). The researcher was an advanced practice nurse and a university faculty who had previous experiences of holding physical activity programs for older Korean Americans in other regions of the United States in the past.
Measurement Measurement of variables occurred at baseline (T1), and at post-intervention (13 weeks, T2) through standardized questionnaires and objective measures of mobility. Data collection took place either in the home or Salvation Army Church; testing procedures were analogous for the MPAI and Attention Control groups. Participants were provided with verbal assistance in completing measures as needed. All measures were available in English and Korean. All of the participants requested translation assistance to complete the questionnaire and asked that their interviews be held in Korean.
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Translation and back-translation of measures were conducted, including English-to-Korean translation by the researcher, back-translation by a bilingual Korean American nursing scholar, back-translation review, and cognitive debriefing to evaluate the conceptual equivalence of the translation and the level of comprehensibility of the scales, in accord with the suggested principles of translation process for measures (Wild et al., 2005). Demographic characteristics. Demographic characteristics included age, gender, years of schooling completed, marital status, employment, medical insurance status, and socioeconomic status, measured as monthly income. Medication use and the presence of comorbid conditions were evaluated using dichotomous yes–no responses. Social resource variables. Social resource variables included social support from family and friends. Social support was measured using the Social Support and Exercise Survey (SSES; Sallis, Grossman, Pinski, Patterson, & Nader, 1987). The SSES-Family and SSES-Friend scales consist of nine items each. Items are rated on scales of 1 to 6, with higher scores indicating greater levels of social support. The internal consistency reliability, measured using Cronbach’s alpha, was .99 at Times 1 and 2 for the SSES-Family, and .99 at Time 1 and .98 at Time 2 for the SSES-Friend. Behavioral change process variables. Behavioral change process variables included self-efficacy, motivational appraisal, and self-regulation. Self-efficacy was measured using the Self-Efficacy for Exercise Scale (SES; Resnick & Jenkins, 2000). The SES consists of 9 items with dichotomous responses, with “yes” scores as 1 and “no” scores as 0. A higher sum score indicated greater self-efficacy for exercise. Cronbach’s alpha reliability was .93 at Time 1 and .88 at Time 2. Motivation appraisal, the construction of intention to initiate and maintain moderate-intensity physical activity, was measured using the Index of Readiness (IR; Fleury & Cameron-Go, 2003). The IR consists of nine items with responses ranging from 1 to 6, with a higher score indicating greater level of readiness to initiate and maintain physical activity. Cronbach’s alpha reliability of the IR was .87 at Time 1 and .93 at Time 2. Self-regulation in maintenance of physical activity was measured using the Index of Self-Regulation (ISR; Yeom, Fleury, Belyea, & Choi, 2011). The ISR consists of 9 items ranging from 1 to 6, with a higher score indicating greater self-regulation for physical activity. Cronbach’s alpha reliability of the ISR was .66 at Time 1 and .78 at Time 2 (Yeom & Fleury, 2011).
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Physical activity behavior. Physical activity behavior was measured using a single item, “Do you currently do any type of regular physical activity for a minimum of 30 min 3 times a week?” According to criteria proposed by the ACSM (Haskell et al., 2007), those who answered “yes” were categorized as engaging in regular physical activity. The validity of the ACSM criteria as measures for physical activity behaviors has been supported in the literature (Nelson et al., 2007; Pinto, Frierson, Rabin, Trunzo, & Marcus, 2005). Mobility. Using performance-based evaluations, mobility was measured in terms of walking endurance and physical performance, which included balance, gait velocity, and flexibility. Mobility levels were measured by the research team, which included the researcher and two research assistants. Each research assistant received individual training on measuring mobility and their measurement skills were tested for the first two cases they interviewed, resulting in 100% agreement between the researcher and the research assistants who record mobility levels. However, there was no interrater reliability measured between the outcome assessors in this study; thus, it should be measured in future studies. Walking endurance was measured using the 6-Minute Walk (6MW) test (Guyatt et al., 1985). The 6MW is a performance-based measure shown to be a valid indicator of mobility function (Bean et al., 2002). Participants were asked to walk as much as possible for 6 min; the number of meters walked was measured. Balance, flexibility, and gait velocity were measured using the Short Physical Performance Battery (SPPB; Guralnik et al., 1994), a performancebased mobility test. Balance was measured as number of seconds standing, by static balance tests including single-legged stance with the eyes open and closed. Flexibility was measured using the Chair Rise Method, which involves a bilateral knee extensor isokinetic peak index. Participants were asked to rise from a series of 6 chair heights ranging from 13 to 23 inches. The Chair Rise score was calculated as the lower height from which the participant could successfully rise without using their arms. Gait velocity was evaluated by asking participants to walk at their usual gait speed, calculating distance over 4 min. Each of the three domains was assigned a score ranging from 0 to 4, with 4 indicating the highest level, and 0 as inability to complete the test. The total SPPB score ranges from 0 to 12, with a higher score indicating better mobility function. The validity of the SPPB has been established (The LIFE Study Investigators, 2006; Ostir, Volpato, Fried, Chaves, & Guralnik, 2002).
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activity, and mobility variables. Attendance and attrition rates, as well as reasons for attrition were evaluated using descriptive statistics. Repeated measures analysis of variance was conducted to examine the effects of the MPAI on social resource, behavioral change process, and mobility variables in sedentary older Korean Americans. A chi-square test was used to evaluate changes in physical activity behavior. The values of p ≤ .05 were considered statistically significant. There was no missing data for this study.
Results Demographic Characteristics Evaluation of homogeneity between MPAI and Attention Control participants resulted in no significant between-group differences in demographic characteristics (Table 1), social resources, behavioral change process variables, physical activity, or mobility at baseline (Table 2). The mean age of the total subjects was 71 years (SD = 7.44), with a range from 60 to 89 years. The mean age was 71 years (SD = 7.52) in the intervention group and 72 years (SD = 7.40) in the control group, showing no significant difference (t = .79; p = .433). The majority of participants were women (76.6%), retired (95.3%), and had medical insurance (92.2%). More than half of participants were living with a spouse or partner (59.4%). About one third of the participants (28.2%) were college graduates, and one third were high school graduates (34.4%). In terms of economic status, 41.2% reported having a monthly income of $1,001 to $3,000. The average duration of residency in the United States was 24 years, with a range from 1 year to 45 years. Participants reported having one or more comorbid conditions (n = 54; 84.4%) and taking medication (n = 54; 84.4%). The average participation rate was 92%; 3 participants in MPAI group withdrew due to admission to hospital or caregiving responsibilities. No adverse events were reported (Figure 2).
Behavioral Change Process and Social Resources Variables There were significant improvements in the social resource variable of social support from family and friends and behavioral change process variables of self-efficacy, motivational appraisal, and self-regulation (Table 3). Scores of MPAI participants increased significantly compared with Attention Control participants in social support from family (F = 21.87; p < .001) and friends (F = 24.72; p < .001), self-efficacy (F = 31.09; p < .001), motivational appraisal for physical activity (F = 79.16; p < .001), and self-regulation (F = 31.51; p < .001). Downloaded from wjn.sagepub.com at NORTH CAROLINA STATE UNIV on March 18, 2015
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Table 1. General Characteristics of Participants. General Characteristics Marital status Spouse Without spouse Gender Female Male Education Over college High school Middle school Less than middle school Job status Yes No Monthly income $0-$1,000 $1,001-$2,000 $2,001-$3,000 $3,001-$5,000 More than $5,000 Medical insurance Yes No Medication status Yes No Morbidity Yes No
Intervention (n = 33) n (%)
Control (n = 31) n (%)
20 (31.3) 13 (20.3)
Total (n = 64) n (%)
χ2
p
18 (28.1) 13 (20.3)
4.10
.393
38 (59.4) 26 (40.6)
23 (35.9) 10 (15.6)
26 (40.6) 5 (7.8)
1.79
.181
49 (76.6) 15 (23.4)
12 (18.7) 8 (12.5) 7 (10.9) 6 (9.4)
6 (9.4) 14 (21.9) 6 (9.4) 5 (7.8)
7.99
.157
18 (28.1) 22 (34.4) 13 (20.3) 11 (17.2)
2 (3.1) 31 (48.4)
1 (1.6) 30 (46.9)
0.29
.592
3 (4.7) 61 (95.3)
9 (14.1) 10 (15.6) 5 (7.8) 6 (9.4) 3 (4.7)
10 (15.6) 5 (7.8) 7 (10.9) 4 (6.3) 5 (7.8)
3.61
.608
19 (29.7) 15 (23.4) 12 (18.7) 10 (15.7) 8 (12.5)
30 (46.9) 3 (4.7)
29 (45.3) 2 (3.1)
0.15
.694
59 (92.2) 5 (7.8)
27 (42.2) 6 (9.4)
27 (42.2) 4 (6.3)
0.34
.561
54 (84.3) 10 (15.7)
27 (42.2) 6 (9.2)
27 (42.2) 4 (6.3)
0.34
.561
54 (84.3) 10 (15.7)
Regular Physical Activity Following the intervention, MPAI participants were more likely to engage in regular physical activity consistent with ACSM criteria compared with the Attention Control participants (χ2 = 25.01; p < .001).
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Yeom and Fleury Table 2. Baseline Characteristics of Participants. Intervention (n = 33) M ± SD
Control (n = 31) M ± SD
Residency in the 22.18 ± 12.26 26.39 ± 10.01 United States Motivational 2.72 ± 0.45 2.62 ± 0.61 appraisal Self-regulation 2.67 ± 0.84 2.52 ± 0.63 Self-efficacy 3.91 ± 3.82 4.16 ± 3.56 6MWT 213.00 ± 98.46 204.03 ± 88.55 SPPB 7.94 ± 2.19 8.87 ± 2.45
t
p
Total (n = 64) n (%) M ± SD
1.50
.139
24.48 ± 11.92
0.76
.451
2.67 ± 0.53
0.77 0.27 0.38 1.61
.447 .786 .704 .113
2.60 ± 0.75 4.03 ± 3.67 208.66 ± 93.16 8.39 ± 2.35
Note. 6MWT = 6-Minute Walk Test; SPPB = Short Physical Performance Battery.
Mobility 6MWT. MPAI participants improved significantly on the 6MWT compared with the Attention Control participants (F = 16.36; p < .001). The mean walk distance increased from 213 m at Time 1 to 251 m at Time 2 in MPAI participants, and decreased from 204 m at Time 1 to 196 m at Time 2 in Attention Control participants. Estimated effect size of the intervention on 6MWT was .59. SPPB. MPAI participants improved significantly on SPPB compared with Attention Control participants (F = 16.28; p < .001). Of SPPB subdomains, MPAI participants had greater increases in the domain of flexibility compared with Attention Control participants (F = 15.46; p < .001). There were no significant differences between the MPAI and Attention Control participants on balance or gait velocity scores (Table 3). Estimated effect size of the intervention on SPPB was .14.
Discussion This study provided initial support for the research question as to whether older Korean Americans receiving the MPAI would show significantly improved social resources, behavioral change processes, physical activity, and mobility over Attention Control participants. Researchers who implement physical activity programs with older Korean Americans may use this theory-based motivational approach focusing on community support
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Figure 2. Flow diagram for subject recruitment.
33 Included in analysis
3 excluded ▪ 2 withdrawn from acute physical illness ▪ 1 declined further participation
36 MPAI group ▪ 27 Salvation Army church members ▪ 9 non-church members
72 Included for participation
75 Screened for eligibility
31 Included in analysis
5 excluded ▪ 2 relocated to other cities ▪ 1 lost to contact ▪ 2 declined further participation
36 Attention Control group
3 excluded for not meeting inclusion criteria
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Table 3. Effects of MPAI on Walking Mobility, Physical Performance, Behavioral Change Process, and Social Resources Variables.
Variables 6MWT SPPB total SPPB-balance SPPB-walking speed SPPB-flexibility Self-regulation for physical activity Self-efficacy for physical activity Readiness for physical activity Social support from family Social support from friends
Control M ± SD
Group F (p)
Time Point Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test
213 ± 98.46 251 ± 110.67 7.94 ± 2.19 9.45 ± 1.82 3.58 ± 0.75 3.94 ± 0.35 2.24 ± 1.00 2.82 ± 0.92 2.15 ± 1.15 2.70 ± 1.13 2.67 ± 0.84 3.77 ± 0.38
204 ± 88.55 1.76 (.190) 7.29 (.009) 196 ± 92.91 8.87 ± 2.45 0.37 (.547) 32.40 (
