Our results suggest that implementation of SB42 impacted the frequency of school PE class statewide and the prevalence of child self-reported physical activity behaviors along the Texas-Mexico border. While our cross-sectional data at the state level preclude us from identifying the causal role of SB42 on physical activity in children, our findings based on two cross-sectional samples of 8th
grade students from the same border schools before and after implementation of SB42 provide some evidence that the average number of PE days per week and self-reported structured physical activity participation increased after the legislation was implemented. Additionally, our conservative estimates from the key informant survey for the statewide sample and direct SOFIT observations and SPAN questionnaire data for the border sample indicate that most middle schools along the border and for the state as a whole are at least meeting the 135 minute weekly requirement for physical activity. These findings are encouraging given the decline in daily PE attendance reported for U.S. high school students [24
], and particularly since schools serving low-income communities, such as Texas-Mexico border schools, may lack resources for implementation of school wellness initiatives.
Although no specific criteria are provided on ‘quality’ of structured physical activity under SB42, we assessed the time students were engaged in MVPA during PE class as a measure of quality physical activity programming. Structured observations of activity levels in PE classes across the border districts suggest that most (mean MVPA 54.9% ± 5.1%) are meeting the Healthy People 2010 objective of 50% time in MVPA during PE class [23
]. Additionally, child self-report of MPA and VPA suggest that border students are approaching the corresponding Healthy People 2010 objectives [23
]. Even though we cannot attribute these findings to SB42 given observations occurred following passage and implementation, these findings are consistent with the intention of SB42 and provide one indication of the quality of physical activity programming in this sample of border schools.
Our findings support previous research on Texas elementary school policy on physical activity that also concluded that schools were meeting or exceeding physical activity requirements [9
]. Because schools along the Texas-Mexico border are among the poorest in the country [13
] and have been faced with several challenges such as high teen pregnancy rates [25
] and low academic scores [26
], we may expect border schools to also lag in implementation of CSHPs. Our positive findings on overall implementation of SB42 in this border sample may provide insight into factors that facilitate implementation of school wellness initiatives. We speculate that the significant increase in number of PE days per week observed in the border sample may be due to greater investments in health promotion campaigns and school programming in border districts as identified by Kelder et al. (2009) [9
]. Investments that may have promoted the implementation of SB42 include the Coordinated Approach To Child Health El Paso school health program [27
], community outreach programs such as Qué Sabrosa Vida [28
] and Walk El Paso project [29
] in El Paso, and, more recently, community-based participatory research programs in Brownsville (NIH/NCHMD Project EXPORT: Excellence in Partnerships for Community Outreach, Research on Health Disparities, and Training).
Overall, general awareness of and adherence to SB42 was high both statewide and among the border districts. While most of the key informants knew of SB42, many had only a partial understanding of what was outlined in the bill as was evident in both the statewide and border data. The parental involvement component of CSH programming and the need to form a SHAC were two aspects of the legislation that merit further attention given the roughly one-third of respondents at the state and border levels that were unaware of these requirements.
Assessment of informational channels for SB42 suggested that many of the key informants learned of the requirements from district offices or professional education sources. Further examination indicated that border key informants learned of SB42 requirements not only from district offices and professional education, but also from other school employees and the news media. Recommendations based on local wellness policy research assert that awareness of school wellness initiatives may improve if a provision for professional development and assistance for school personnel involved in the implementation of these initiatives is included [30
]. Because many of the key informants learned of SB42 through professional education sources, this may hold true for this sample.
Even though border school districts reported awareness of and adherence to SB42, no significant changes in BMI and sedentary behavior (daily TV watching/playing video games) were observed in students between the two time periods. Firstly, increased physical activity through improved PE class frequency or quality of PE has been found to be insufficient to influence BMI levels [32
]. Secondly, it is possible that insufficient amount of time between the start date of SB42 (2006–2007) and our assessment (2006–2008) elapsed to observe differences in student sedentary behaviors. At the same time, the lack of change in TV watching but increased number of PE days per week before and after SB42 may speak to the potential for state policy to increase physical activity at the school level while underscoring the continued challenges for changing individual-level behavior change outside the school setting.
These findings contribute to an emerging body of research that suggests that policy can positively affect obesity-related factors in the school environment [7
]. For example, policy requirements for PE attendance have been found to provide an average of 31 additional minutes per week that students spend in physical activity in PE class in U.S. high schools [33
]. An environmental and policy intervention evaluated in 24 U.S. middle schools was found to have significant effects on physical activity for the total group and boys, but not girls [34
]. A policy-based school intervention in 10 elementary schools in the U.S. that emphasized nutrition policy and social marketing was found to significantly decrease obesity incidence among intervention elementary school students [35
]. Similarly, in Utah, a small observational study (n=4 elementary schools) by Jordan et al. (2008) found that children attending schools that met specific physical activity, nutrition and obesity prevention policy and wellness criteria under the “Gold Medal Schools Program” had no significant increases in BMI z
scores compared to children in “non-Gold Medal schools”, whose BMI significantly increased [36
]. These studies provide support for the role of policy in driving physical activity and other health-related behaviors among students. With emerging literature on the measurement of school-based policy [37
] to better inform policy research design, future research in school-based policy is needed to identify the specific factors that contribute to policy development, dissemination, and monitoring as well as the causal role of school policy in obesity prevention.
This study does have limitations. While we cannot rule out social desirability bias from key informants regarding the number of structured physical activity minutes reported per class and days per week, we were able to provide some support for these findings through the triangulation of key informant, SOFIT direct observations, and student reports at the border level. Even though our assessment of statewide implementation of SB42 and the SOFIT measures with the border sample relied on a single time period and we cannot infer causality, our border-level data afforded a comprehensive examination of the execution of this mandate, including the utilization of multiple methods of assessments (key informant, direct observation, and student report) as well as measures taken before and after implementation of SB42. Finally, other sources of structured physical activity (such as physical activity breaks) were not assessed, which may have resulted in an underestimation of structured physical activity.
The important discrepancies in awareness and action around SB42 found in this study suggest the need for better understanding of the factors that both facilitate and inhibit local leadership around school policy, communication channels to disseminate school policy, and mechanisms to ensure school policy is being implemented. To better understand factors that facilitate adherence to SB42 and other school wellness initiatives, future assessments should include: 1) comparisons regarding PE class length and frequency and MVPA during PE class between the different types of PE classes offered in schools (grade-specific PE, mixed-grade PE, co-ed PE, gender-specific PE); 2) use of other venues for structured physical activity (intramural sports and sports teams) to meet policy standards and objectives; 3) access to school facilities for physical activity (e.g., gyms, tracks, weight rooms) before and after school as well as other school environment changes that promote school wellness for the entire school community (students, staff, and parents); and 4) barriers to PE and physical activity (limitations in staff, lack of equipment and materials, class size, low academic priority, and limited financial resources), all of which may impact schools’ ability to adhere to the initiatives. In regards to SB42, further research should assess the impact of Senate Bill 530, enacted in 2007 to strengthen the objectives of Senate Bill 19 (predecessor of SB42 and targeting elementary school children) and SB42, on adherence to the PE class requirement of four semesters for middle schools and annual physical fitness assessments of students.
In summary, our findings based on state and border samples of Texas middle schools suggest that most schools in Texas are adhering to SB42 and that schools are meeting or exceeding the required number of structured physical activity minutes. The significant increase in frequency of PE observed in our border sample before and after implementation of SB42 provides some evidence that state level policies can impact student physical activity participation. At the same time, because knowledge and adherence to specific components of SB42 varied among both a representative sample of Texas public middle schools and schools from four Texas-Mexico border municipalities- with approximately 1 in 4 schools unaware of the physical activity requirement, further support is warranted to increase implementation and adherence. The emergence of school wellness initiatives to address child obesity presents an important opportunity to promote child health at a system’s level. As such, continued monitoring of implementation and research on the efficacy of these initiatives at the local level [30
] are warranted to assess health-related goals as well as make needed policy refinements so that intended effects can be achieved.