Implementing Resistance Training in Secondary Schools: A Cluster Randomized Controlled Trial.

PURPOSE: Guidelines recommend that young people engage in muscle-strengthening activities on at least 3 d·wk. The purpose of this study was to examine the effect of a school-based intervention focused on resistance training (RT) for adolescents. METHODS: The "Resistance Training for Teens" intervention was evaluated using a cluster-randomized, controlled trial with 607 adolescents (50.1% girls; 14.1 ± 0.5 yr) from 16 secondary schools. Teachers were trained to deliver the intervention, which included the following: (i) an interactive student seminar; (ii) a structured physical activity program, focused on RT; (iii) lunchtime fitness sessions; and (iv) Web-based smartphone apps. The primary outcome was muscular fitness (MF) and secondary outcomes included body mass index, RT skill competency, flexibility, physical activity, self-efficacy, and motivation. Assessments were conducted at baseline, 6 months (postprogram; primary end point), and 12 months (follow-up). Outcomes were assessed using linear mixed models, with three potential moderators tested using interaction terms (and subgroup analyses where appropriate). RESULTS: For the primary outcome (MF), a group-time effect was observed at 6 months for the upper body (2.0 repetitions; 95% confidence interval (CI), 0.8-3.2), but not the lower body (-1.4 cm; 95% CI, -4.7-1.9). At 6 months, there were intervention effects for RT skill competency and self-efficacy, but no other secondary outcomes. Effects for upper body MF and RT skill competency were sustained at 12 months. Despite overall no effect for body mass index, there was a group-time effect at 12 months among students who were overweight/obese at baseline (-0.55 kg·m; 95% CI, -1.01 to -0.08). CONCLUSIONS: The school-based RT intervention resulted in immediate and sustained improvements in upper body MF and RT skill competency, demonstrating an effective and scalable approach to delivering RT within secondary schools.

A school-based intervention incorporating smartphone technology to improve health-related fitness among adolescents: rationale and study protocol for the NEAT and ATLAS 2.0 cluster randomised controlled trial and dissemination study.

INTRODUCTION: Physical inactivity has been described as a global pandemic. Interventions aimed at developing skills in lifelong physical activities may provide the foundation for an active lifestyle into adulthood. In general, school-based physical activity interventions targeting adolescents have produced modest results and few have been designed to be 'scaled-up' and disseminated. This study aims to: (1) assess the effectiveness of two physical activity promotion programmes (ie, NEAT and ATLAS) that have been modified for scalability; and (2) evaluate the dissemination of these programmes throughout government funded secondary schools. METHODS AND ANALYSIS: The study will be conducted in two phases. In the first phase (cluster randomised controlled trial), 16 schools will be randomly allocated to the intervention or a usual care control condition. In the second phase, the Reach, Effectiveness, Adoption, Implementation and Maintenance (Re-AIM) framework will be used to guide the design and evaluation of programme dissemination throughout New South Wales (NSW), Australia. In both phases, teachers will be trained to deliver the NEAT and ATLAS programmes, which will include: (1) interactive student seminars; (2) structured physical activity programmes; (3) lunch-time fitness sessions; and (4) web-based smartphone apps. In the cluster RCT, study outcomes will be assessed at baseline, 6 months (primary end point) and 12-months. Muscular fitness will be the primary outcome and secondary outcomes will include: objectively measured body composition, cardiorespiratory fitness, flexibility, resistance training skill competency, physical activity, self-reported recreational screen-time, sleep, sugar-sweetened beverage and junk food snack consumption, self-esteem and well-being. ETHICS AND DISSEMINATION: This study has received approval from the University of Newcastle (H-2014-0312) and the NSW Department of Education (SERAP: 2012121) human research ethics committees. This study is funded by the Australian Research Council (FT140100399) and the NSW Department of Education. TRIAL REGISTRATION NUMBER: ACTRN12615000360516; Pre-results.

Social cognitive mediators of dietary behavior change in adolescent girls.

OBJECTIVES: To examine potential mediators of adolescent girls' dietary behavior change in the Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention for obesity prevention. METHODS: Participants were 294 adolescent girls attending 12 secondary schools located in low-income communities of New South Wales, Australia. Hypothesized social cognitive mediators of dietary behavior change were assessed using valid and reliable scales. RESULTS: The intervention effects on dietary outcomes and hypothesized mediators were not statistically significant. However, changes in hypothesized mediators were associated with changes in key dietary behaviors. CONCLUSIONS: Continued research is needed to examine effective strategies for improving dietary outcomes in youth, and to explore alternative theoretical mechanisms of dietary behavior change.

Exploring changes in physical activity, sedentary behaviors and hypothesized mediators in the NEAT girls group randomized controlled trial.

OBJECTIVE: To evaluate the impact of a 12-month school-based multi-component program on adolescent girls' physical activity and sedentary behaviors, and hypothesized mediators of physical activity behavior change. DESIGN: Group randomized controlled trial with 12-month follow-up. METHODS: The intervention, guided by Social Cognitive Theory, involved 357 adolescent girls (13.2 ± 0.5 years) from 12 secondary schools (6 intervention schools, 6 control schools) in low-income communities in the Hunter and Central Coast regions of New South Wales, Australia. The intervention included enhanced school sport, lunchtime physical activity sessions, interactive seminars, student handbooks, nutrition workshops, pedometers, parent newsletters and text messages to encourage physical activity and healthy eating, and a decrease in sedentary behavior. Outcomes were assessed at baseline and 12-months and included: physical activity (accelerometers), sedentary behaviors (questionnaire and accelerometers), and social-cognitive mediators of physical activity (questionnaire). RESULTS: There were significant between group differences in favor of the intervention group for self-reported recreational computer use (-26.0 min; 95% CI, -46.9 to -5.1), and sedentary activities summed (-56.4 min; 95% CI, -110.1 to -2.7), however objective sedentary behavior showed no differences. There were no group-by-time effects for any of the physical activity outcomes or hypothesized mediators. CONCLUSIONS: A school-based intervention tailored for adolescent girls from schools located in low-income communities significantly reduced time spent in sedentary activities. However, improvements in physical activity and hypothesized mediators of physical activity behavior were not observed. Future studies are encouraged to explore alternative mechanisms of behavior change derived from integrated and socio-ecological theories.

12 month changes in dietary intake of adolescent girls attending schools in low-income communities following the NEAT Girls cluster randomized controlled trial.

Poor dietary habits and obesity are more prevalent in lower socio-economic status (SES) communities. The NEAT Girls cluster randomized controlled trial was a school-based obesity prevention program targeting adolescent girls in low SES schools in NSW, Australia. The aim was to evaluate the 12-month impact of key nutrition program messages on dietary intake and food behaviors. Diet was assessed using a validated semi-quantitative food frequency questionnaire (FFQ). Individual foods were categorized into nutrient-dense or energy-dense, nutrient-poor food groups and the percentage contribution to total energy intake calculated. Participants were aged 13.2±0.5years (n=330). There were no statistically significant group-by-time effects for dietary intake or food related behaviors, with 12-month trends suggesting more intervention group girls had improved water intakes (59% consuming⩽three glasses per day to 54% at 12 months vs. 50% to 61% in controls, p=0.052), with a greater proportion consuming < one sweetened beverage per day (24-41% vs. 34-37% in controls, p=0.057). Further research including more intensive nutrition intervention strategies are required to evaluate whether dietary intake in adolescent girls attending schools in low SES communities can be optimized.

The nutrition and enjoyable activity for teen girls study: a cluster randomized controlled trial.

BACKGROUND: Obesity prevention among youth of low SES is a public health priority given the higher prevalence of youth obesity in this population subgroup. PURPOSE: To evaluate the 24-month impact of a school-based obesity prevention program among adolescent girls living in low-income communities. DESIGN: The study was a school-based group RCT, the Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention. SETTING/PARTICIPANTS: The study involved 12 secondary schools located in low-income communities in New South Wales, Australia. Participants were 357 adolescent girls (aged 13.2 ± 0.5 years). INTERVENTION: The 12-month multicomponent intervention was guided by social cognitive theory and involved strategies to promote physical activity, reduce sedentary behaviors, and improve dietary outcomes. MAIN OUTCOME MEASURES: The primary outcome was BMI, and secondary outcomes were BMI z-score; percentage body fat (bioelectrical impedance analysis); physical activity (accelerometers); dietary intake; and recreational screen-time (self-report). Data were collected in 2010-2012 and analyzed in 2012. RESULTS: After 24 months, there were no intervention effects on BMI (adjusted mean difference -0.33, 95% CI= -0.97, 0.28, p=0.353) and BMI z-score (-0.12, 95% CI= -0.27, 0.04, p=0.178). However, there was a group-by-time interaction for percentage body fat (-1.96%, 95% CI= -3.02, -0.89, p=0.006). Intervention effects for physical activity, screen time, and dietary intake were not significant. CONCLUSIONS: The NEAT Girls intervention did not result in effects on the primary outcome. Further study of youth who are "at risk" of obesity should focus on strategies to improve retention and adherence in prevention programs. TRIAL REGISTRATION: This study is registered at Australian New Zealand Clinical Trials ACTRN1261000033004.

Testing social-cognitive theory to explain physical activity change in adolescent girls from low-income communities.

PURPOSE: The aim of this study was to test the hypothesized structural paths in Bandura's social-cognitive theory (SCT) model on adolescent girls' physical activity following a 12-month physical activity and dietary intervention to prevent obesity. METHOD: We conducted a 12-month follow-up study of 235 adolescent girls (M(age) = 13.2 years, SD = 0.4) from 12 secondary schools located in low-income communities. At baseline, participants completed SCT scales related to physical activity (i.e., self-efficacy, intention, parental support, and outcome expectations). At baseline and 12-month follow-up (postintervention), participants wore accelerometers for 7 days. Structural equation modeling was used to determine if Time 1 measures predicted physical activity at 12-month follow-up after adjusting for baseline activity. RESULTS: The model explained 28% and 34% of the variance in physical activity and intention, respectively. Model fit indexes indicated the data were a good fit to the model; however, only self-efficacy was associated with physical activity at 12 months. There was no support for intention or outcome expectations as proximal determinants of behavior. Self-efficacy was associated with outcome expectations and parental support; however, only outcome expectations predicted intention. CONCLUSIONS: Current findings indicate a large proportion of the variance for physical activity and intention remains unexplained and that the proposed pathways in the SCT model were not fully supported. Future model testing may need to consider augmentation or integration of theoretical models, which may include ecological components if we are to advance our understanding of physical activity behavior in this subgroup of the adolescent population.

Development and evaluation of social cognitive measures related to adolescent physical activity.

BACKGROUND: This study aimed to develop and evaluate the construct validity and reliability of modernized social cognitive measures relating to physical activity behaviors in adolescents. METHODS: An instrument was developed based on constructs from Bandura's Social Cognitive Theory and included the following scales: self-efficacy, situation (perceived physical environment), social support, behavioral strategies, and outcome expectations and expectancies. The questionnaire was administered in a sample of 171 adolescents (age = 13.6 ± 1.2 years, females = 61%). Confirmatory factor analysis was employed to examine model-fit for each scale using multiple indices, including chi-square index, comparative-fit index (CFI), goodness-of-fit index (GFI), and the root mean square error of approximation (RMSEA). Reliability properties were also examined (ICC and Cronbach's alpha). RESULTS: Each scale represented a statistically sound measure: fit indices indicated each model to be an adequate-to-exact fit to the data; internal consistency was acceptable to good (α = 0.63-0.79); rank order repeatability was strong (ICC = 0.82-0.91). CONCLUSIONS: Results support the validity and reliability of social cognitive scales relating to physical activity among adolescents. As such, the developed scales have utility for the identification of potential social cognitive correlates of youth physical activity, mediators of physical activity behavior changes and the testing of theoretical models based on Social Cognitive Theory.

Rationale and study protocol for the supporting children's outcomes using rewards, exercise and skills (SCORES) group randomized controlled trial: a physical activity and fundamental movement skills intervention for primary schools in low-income communities.

BACKGROUND: Many Australian children are insufficiently active to accrue health benefits and physical activity (PA) levels are consistently lower among youth of low socio-economic position. PA levels decline dramatically during adolescence and evidence suggests that competency in a range of fundamental movement skills (FMS) may serve as a protective factor against this trend. METHODS/DESIGN: The Supporting Children's Outcomes Using Rewards Exercise and Skills (SCORES) intervention is a multi-component PA and FMS intervention for primary schools in low-income communities, which will be evaluated using a group randomized controlled trial. The socio-ecological model provided a framework for the 12-month intervention, which includes the following components: teacher professional learning, student leadership workshops (including leadership accreditation and rewards, e.g., stickers, water bottles), PA policy review, PA equipment packs, parental engagement via newsletters, FMS homework and a parent evening, and community partnerships with local sporting organizations. Outcomes will be assessed at baseline, 6- and 12-months. The primary outcomes are PA (accelerometers), FMS (Test of Gross Motor Development II) and cardiorespiratory fitness (multi-stage fitness test). Secondary outcomes include body mass index [using weight (kg)/height (m2)], perceived competence, physical self-esteem, and resilience. Individual and environmental mediators of behavior change (e.g. social support and enjoyment) will also be assessed. The System for Observing Fitness Instruction Time will be used to assess the impact of the intervention on PA within physical education lessons. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA behavior change will be explored. DISCUSSION: SCORES is an innovative primary school-based PA and FMS intervention designed to support students attending schools in low-income communities to be more skilled and active. The findings from the study may be used to guide teacher pre-service education, professional learning and school policy in primary schools. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry No: ACTRN12611001080910.

Development and evaluation of social cognitive measures related to adolescent dietary behaviors.

BACKGROUND: This study aimed to develop and evaluate the reliability and factorial validity, of social-cognitive measures related to adolescent healthy eating behaviors. METHODS: A questionnaire was developed based on constructs from Bandura's Social Cognitive Theory and included the following scales: self-efficacy, intentions (proximal goals), situation (perceived environment), social support, behavioral strategies, outcome expectations and expectancies. The questionnaire was administered with a two week test-retest among secondary school students (n = 173, age = 13.72 ± 1.24). Confirmatory factor analysis was employed to examine model-fit for each scale using multiple indices including: chi-square index, comparative-fit index (CFI), goodness-of-fit index (GFI), and the root mean square error of approximation (RMSEA). Reliability properties were also examined (ICC and Cronbach's alpha). RESULTS: The reliability and factorial validity of each scale is supported: fit indices suggest each model to be an adequate-to-exact fit to the data; internal consistency was acceptable-to-good (α = 0.65-0.79); rank order repeatability was strong (ICC = 0.81-0.89). CONCLUSIONS AND IMPLICATIONS: Results support the reliability and factorial validity of social cognitive scales relating to healthy eating behaviors among adolescents. As such, the developed scales have utility for identifying potential social cognitive correlates of adolescent dietary behavior, mediators of dietary behavior change and validity testing of theoretical models based on Social Cognitive Theory.