"Girls on the Move" intervention protocol for increasing physical activity among low-active underserved urban girls: a group randomized trial

Interventions to prevent obesity in children aged 12 to 18 years old

BACKGROUND

Prevention of obesity in adolescents is an international public health priority. The prevalence of overweight and obesity is over 25% in North and South America, Australia, most of Europe, and the Gulf region. Interventions that aim to prevent obesity involve strategies that promote healthy diets or 'activity' levels (physical activity, sedentary behaviour and/or sleep) or both, and work by reducing energy intake and/or increasing energy expenditure, respectively. There is uncertainty over which approaches are more effective, and numerous new studies have been published over the last five years since the previous version of this Cochrane Review.

OBJECTIVES

To assess the effects of interventions that aim to prevent obesity in adolescents by modifying dietary intake or 'activity' levels, or a combination of both, on changes in BMI, zBMI score and serious adverse events.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was February 2023.

SELECTION CRITERIA

Randomised controlled trials in adolescents (mean age 12 years and above but less than 19 years), comparing diet or 'activity' interventions (or both) to prevent obesity with no intervention, usual care, or with another eligible intervention, in any setting. Studies had to measure outcomes at a minimum of 12 weeks post baseline. We excluded interventions designed primarily to improve sporting performance.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our outcomes were BMI, zBMI score and serious adverse events, assessed at short- (12 weeks to < 9 months from baseline), medium- (9 months to < 15 months) and long-term (≥ 15 months) follow-up. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

This review includes 74 studies (83,407 participants); 54 studies (46,358 participants) were included in meta-analyses. Sixty studies were based in high-income countries. The main setting for intervention delivery was schools (57 studies), followed by home (nine studies), the community (five studies) and a primary care setting (three studies). Fifty-one interventions were implemented for less than nine months; the shortest was conducted over one visit and the longest over 28 months. Sixty-two studies declared non-industry funding; five were funded in part by industry. Dietary interventions versus control The evidence is very uncertain about the effects of dietary interventions on body mass index (BMI) at short-term follow-up (mean difference (MD) -0.18, 95% confidence interval (CI) -0.41 to 0.06; 3 studies, 605 participants), medium-term follow-up (MD -0.65, 95% CI -1.18 to -0.11; 3 studies, 900 participants), and standardised BMI (zBMI) at long-term follow-up (MD -0.14, 95% CI -0.38 to 0.10; 2 studies, 1089 participants); all very low-certainty evidence. Compared with control, dietary interventions may have little to no effect on BMI at long-term follow-up (MD -0.30, 95% CI -1.67 to 1.07; 1 study, 44 participants); zBMI at short-term (MD -0.06, 95% CI -0.12 to 0.01; 5 studies, 3154 participants); and zBMI at medium-term (MD 0.02, 95% CI -0.17 to 0.21; 1 study, 112 participants) follow-up; all low-certainty evidence. Dietary interventions may have little to no effect on serious adverse events (two studies, 377 participants; low-certainty evidence). Activity interventions versus control Compared with control, activity interventions do not reduce BMI at short-term follow-up (MD -0.64, 95% CI -1.86 to 0.58; 6 studies, 1780 participants; low-certainty evidence) and probably do not reduce zBMI at medium- (MD 0, 95% CI -0.04 to 0.05; 6 studies, 5335 participants) or long-term (MD -0.05, 95% CI -0.12 to 0.02; 1 study, 985 participants) follow-up; both moderate-certainty evidence. Activity interventions do not reduce zBMI at short-term follow-up (MD 0.02, 95% CI -0.01 to 0.05; 7 studies, 4718 participants; high-certainty evidence), but may reduce BMI slightly at medium-term (MD -0.32, 95% CI -0.53 to -0.11; 3 studies, 2143 participants) and long-term (MD -0.28, 95% CI -0.51 to -0.05; 1 study, 985 participants) follow-up; both low-certainty evidence. Seven studies (5428 participants; low-certainty evidence) reported data on serious adverse events: two reported injuries relating to the exercise component of the intervention and five reported no effect of intervention on reported serious adverse events. Dietary and activity interventions versus control Dietary and activity interventions, compared with control, do not reduce BMI at short-term follow-up (MD 0.03, 95% CI -0.07 to 0.13; 11 studies, 3429 participants; high-certainty evidence), and probably do not reduce BMI at medium-term (MD 0.01, 95% CI -0.09 to 0.11; 8 studies, 5612 participants; moderate-certainty evidence) or long-term (MD 0.06, 95% CI -0.04 to 0.16; 6 studies, 8736 participants; moderate-certainty evidence) follow-up. They may have little to no effect on zBMI in the short term, but the evidence is very uncertain (MD -0.09, 95% CI -0.2 to 0.02; 3 studies, 515 participants; very low-certainty evidence), and they may not reduce zBMI at medium-term (MD -0.05, 95% CI -0.1 to 0.01; 6 studies, 3511 participants; low-certainty evidence) or long-term (MD -0.02, 95% CI -0.05 to 0.01; 7 studies, 8430 participants; low-certainty evidence) follow-up. Four studies (2394 participants) reported data on serious adverse events (very low-certainty evidence): one reported an increase in weight concern in a few adolescents and three reported no effect.

AUTHORS' CONCLUSIONS

The evidence demonstrates that dietary interventions may have little to no effect on obesity in adolescents. There is low-certainty evidence that activity interventions may have a small beneficial effect on BMI at medium- and long-term follow-up. Diet plus activity interventions may result in little to no difference. Importantly, this updated review also suggests that interventions to prevent obesity in this age group may result in little to no difference in serious adverse effects. Limitations of the evidence include inconsistent results across studies, lack of methodological rigour in some studies and small sample sizes. Further research is justified to investigate the effects of diet and activity interventions to prevent childhood obesity in community settings, and in young people with disabilities, since very few ongoing studies are likely to address these. Further randomised trials to address the remaining uncertainty about the effects of diet, activity interventions, or both, to prevent childhood obesity in schools (ideally with zBMI as the measured outcome) would need to have larger samples.

A Tailored mHealth Intervention for Improving Antenatal Care Seeking and Health Behavioral Determinants During Pregnancy Among Adolescent Girls and Young Women in South Africa: Development and Protocol for a Pilot Randomized Controlled Trial

BACKGROUND

South Africa, a middle-income country, has an adolescent fertility rate far higher than that of high-income countries. Adolescent girls and young women have an increased risk of pregnancy-related complications and lower antenatal appointment attendance rates than older adult pregnant women. Mobile health (mHealth) interventions to improve health behaviors among pregnant adolescent girls and young women in low- and middle-income countries are scarce.

OBJECTIVE

This paper describes the development and components of an mHealth intervention to improve antenatal appointment attendance and health behavioral determinants among pregnant adolescent girls and young women in South Africa and details the protocol for a pilot randomized controlled trial that evaluated the intervention's efficacy and user acceptability.

METHODS

The intervention, Teen MomConnect, sent tailored motivational behavior change and behavioral reinforcement SMS text messages to participants about antenatal appointment keeping and pregnancy behaviors. The delivery methodology of the intervention was adapted from MomConnect, an mHealth education program for pregnant women in South Africa that has nationwide coverage. In addition, participants received a face-to-face motivational interviewing session delivered by a trained research assistant. Pregnant adolescent girls and young women aged 13 to 20 years were recruited from health facilities and community networks. Participants were randomized into the control group that received the standard MomConnect health SMS text messages or the experimental group that received the Teen MomConnect intervention. Participants completed a baseline questionnaire upon enrollment in the study and a follow-up questionnaire after the end of their pregnancy. The questionnaires assessed demographic characteristics, pregnancy behaviors, and the psychosocial determinants of antenatal appointment attendance (knowledge, attitudes, social support, risk perceptions, self-efficacy, intention, and action planning). Feasibility was assessed using descriptive analyses of acceptability, study implementation processes, and perceived satisfaction with the intervention. The number of appointments attended was obtained from the participants' clinic records. Appointment attendance was compared between the control and experimental groups, as were awareness of HIV status and the psychosocial determinants of antenatal appointment attendance.

RESULTS

Participant recruitment was conducted from May 2018 to December 2018, and the questionnaire-based data collection was completed by December 2019. Overall, 412 participants were enrolled.

CONCLUSIONS

This paper describes the Teen MomConnect intervention to improve antenatal appointment attendance and pregnancy health behaviors among adolescent girls and young women. The results on the intervention's preliminary efficacy and user acceptability will inform policy makers and health program officers on how tailored, age-appropriate, and motivational health behavior messages can be delivered via mobile phone to pregnant adolescent girls and young women.

TRIAL REGISTRATION

Pan African Clinical Trial Registry (PACTR) PACTR201912734889796; https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9565.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/43654.

Controlling Hypertension through Education and Coaching in Kidney Disease (CHECK-D): protocol of a cluster randomised controlled trial

INTRODUCTION

Chronic kidney disease (CKD) affects 30 million Americans. Early management focused on blood pressure (BP) control decreases cardiovascular morbidity and mortality. Less than 40% of patients with CKD achieve recommended BP targets due to many barriers. These barriers include a lack of understanding of the implications of their diagnosis and how to optimise their health.This cluster randomised control trial hypothesises that the combination of early primary care CKD education, and motivational interviewing (MI)-based health coach support, will improve patient behaviours aligned with BP control by increasing patient knowledge, self-efficacy and motivation. The results will aid in sustainable interventions for future patient-centric education and coaching support to improve quality and outcomes in patients with CKD stages 3-5. Outcomes in patients with CKD stages 3-5 receiving the intervention will be compared with similar patients within a control group. Continuous quality improvement (CQI) and systems methodologies will be used to optimise resource neutrality and leverage existing technology to support implementation and future dissemination. The innovative approach of this research focuses on the importance of a multidisciplinary team, including off-site patient coaching, that can intervene early in the CKD care continuum by supporting patients with education and coaching.

METHODS AND ANALYSIS

We will test impact of BP control when clinician-delivered education is followed by 12 months of MI-based health coaching. We will compare outcomes in 350 patients with CKD stages 3-5 between intervention and control groups in primary care. CQI and systems methodologies will optimise education and coaching for future implementation and dissemination.

ETHICS AND DISSEMINATION

This study was approved by the University of Michigan Institutional Review Boards (IRBMED) HUM00136011, HUM00150672 and SITE00000092 and the results of the study will be published on ClinicalTrials.gov, in peer-reviewed journals, as well as conference abstracts, posters and presentations.

TRIAL REGISTRATION NUMBER

NCT04087798.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18

BACKGROUND

Physical activity among children and adolescents is associated with lower adiposity, improved cardio-metabolic health, and improved fitness. Worldwide, fewer than 30% of children and adolescents meet global physical activity recommendations of at least 60 minutes of moderate to vigorous physical activity per day. Schools may be ideal sites for interventions given that children and adolescents in most parts of the world spend a substantial amount of time in transit to and from school or attending school.

OBJECTIVES

The purpose of this review update is to summarise the evidence on effectiveness of school-based interventions in increasing moderate to vigorous physical activity and improving fitness among children and adolescents 6 to 18 years of age. Specific objectives are: • to evaluate the effects of school-based interventions on increasing physical activity and improving fitness among children and adolescents; • to evaluate the effects of school-based interventions on improving body composition; and • to determine whether certain combinations or components (or both) of school-based interventions are more effective than others in promoting physical activity and fitness in this target population.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, BIOSIS, SPORTDiscus, and Sociological Abstracts to 1 June 2020, without language restrictions. We screened reference lists of included articles and relevant systematic reviews. We contacted primary authors of studies to ask for additional information.

SELECTION CRITERIA

Eligible interventions were relevant to public health practice (i.e. were not delivered by a clinician), were implemented in the school setting, and aimed to increase physical activity among all school-attending children and adolescents (aged 6 to 18) for at least 12 weeks. The review was limited to randomised controlled trials. For this update, we have added two new criteria: the primary aim of the study was to increase physical activity or fitness, and the study used an objective measure of physical activity or fitness. Primary outcomes included proportion of participants meeting physical activity guidelines and duration of moderate to vigorous physical activity and sedentary time (new to this update). Secondary outcomes included measured body mass index (BMI), physical fitness, health-related quality of life (new to this update), and adverse events (new to this update). Television viewing time, blood cholesterol, and blood pressure have been removed from this update.  DATA COLLECTION AND ANALYSIS: Two independent review authors used standardised forms to assess each study for relevance, to extract data, and to assess risk of bias. When discrepancies existed, discussion occurred until consensus was reached. Certainty of evidence was assessed according to GRADE. A random-effects meta-analysis based on the inverse variance method was conducted with participants stratified by age (children versus adolescents) when sufficient data were reported. Subgroup analyses explored effects by intervention type.

MAIN RESULTS

Based on the three new inclusion criteria, we excluded 16 of the 44 studies included in the previous version of this review. We screened an additional 9968 titles (search October 2011 to June 2020), of which 978 unique studies were potentially relevant and 61 met all criteria for this update. We included a total of 89 studies representing complete data for 66,752 study participants. Most studies included children only (n = 56), followed by adolescents only (n = 22), and both (n = 10); one study did not report student age. Multi-component interventions were most common (n = 40), followed by schooltime physical activity (n = 19), enhanced physical education (n = 15), and before and after school programmes (n = 14); one study explored both enhanced physical education and an after school programme. Lack of blinding of participants, personnel, and outcome assessors and loss to follow-up were the most common sources of bias.  Results show that school-based physical activity interventions probably result in little to no increase in time engaged in moderate to vigorous physical activity (mean difference (MD) 0.73 minutes/d, 95% confidence interval (CI) 0.16 to 1.30; 33 studies; moderate-certainty evidence) and may lead to little to no decrease in sedentary time (MD -3.78 minutes/d, 95% CI -7.80 to 0.24; 16 studies; low-certainty evidence). School-based physical activity interventions may improve physical fitness reported as maximal oxygen uptake (VO₂max) (MD 1.19 mL/kg/min, 95% CI 0.57 to 1.82; 13 studies; low-certainty evidence). School-based physical activity interventions may result in a very small decrease in BMI z-scores (MD -0.06, 95% CI -0.09 to -0.02; 21 studies; low-certainty evidence) and may not impact BMI expressed as kg/m² (MD -0.07, 95% CI -0.15 to 0.01; 50 studies; low-certainty evidence). We are very uncertain whether school-based physical activity interventions impact health-related quality of life or adverse events.

AUTHORS' CONCLUSIONS

Given the variability of results and the overall small effects, school staff and public health professionals must give the matter considerable thought before implementing school-based physical activity interventions. Given the heterogeneity of effects, the risk of bias, and findings that the magnitude of effect is generally small, results should be interpreted cautiously.

Moderators in a physical activity intervention for adolescent girls

BACKGROUND

The purpose was to explore whether baseline sociodemographic and physical characteristics moderated effects of an intervention on moderate-to-vigorous physical activity (MVPA), percent body fat, body mass index z-score, and cardiorespiratory fitness (CRF) at post intervention, relative to the control condition.

METHODS

A secondary analysis of data from a group randomized trial including 24 schools (12 intervention and 12 control; N = 1519 girls) was conducted. Age, ethnicity, race, socioeconomic status, and pubertal stage were assessed via survey. Height, weight, MVPA (min/h), percent body fat, and CRF were measured. Mixed-effects linear models were performed.

RESULTS

Compared to the control, the intervention increased overweight and obese girls' CRF (b = 0.28, p = 0.049; b = 0.31, p < 0.01, respectively), but not healthy weight girls' CRF (b = 0.04, p = 0.706). Pre- to mid-puberty girls in the intervention group had slightly lower post-intervention MVPA than those in the control (3.04 vs. 3.31, p = 0.055), while late to post-puberty intervention and control girls' post-intervention MVPA was similar (3.12 vs. 3.04, p = 0.542).

CONCLUSIONS

A PA intervention can improve overweight and obese girls' CRF, possibly attenuating their cardiovascular risk. Effective strategies are needed to assist adolescent girls, especially those in pre- to mid-puberty, in maintaining their MVPA after an intervention ends.

IMPACT

Moderators of physical activity intervention effects among adolescent girls are important to identify because the effectiveness of these interventions to date in this population has been limited. This article contributes to the notable gap in knowledge regarding moderators in physical activity interventions involving adolescent girls, particularly baseline characteristics that may moderate their responses to physical activity interventions. Awareness of the moderators can be useful for determining the type of intervention that may be successful in subgroups of adolescent girls and for tailoring a physical activity intervention to optimally meet each girl's needs to achieve maximal effects. Findings show that weight status moderated the intervention effects on cardiorespiratory fitness. Compared to the control condition, the intervention increased overweight and obese, but not healthy weight, girls' cardiorespiratory fitness. A physical activity intervention can improve overweight and obese girls' cardiorespiratory fitness, possibly attenuating their cardiovascular risk. Therefore, it is essential to include overweight and obese girls in PA interventions to help them reap this important benefit.

Gaelic4Girls-The Effectiveness of a 10-Week Multicomponent Community Sports-Based Physical Activity Intervention for 8 to 12-Year-Old Girls

Girls are less active than boys throughout childhood and adolescence, with limited research focusing on female community sports-based programs. This study aims to assess the effectiveness of a multi-component, community sports-based intervention for increasing girl's physical activity (PA) levels, fundamental movement skill (FMS) proficiency, and psychological wellbeing, as relative to a second treatment group (the traditionally delivered national comparative program), and a third control group. One hundred and twenty female-only participants (mean age = 10.75 ± 1.44 years), aged 8 to 12 years old from three Ladies Gaelic Football (LGF) community sports clubs (rural and suburban) were allocated to one of three conditions: (1) Intervention Group 1 (n = 43) received a novel, specifically tailored, research-informed Gaelic4Girls (G4G) intervention; (2) Intervention Group 2 (n = 44) used the traditionally delivered, national G4G program, as run by the Ladies Gaelic Football (LGF) Association of Ireland; and (3) Control Group 3 (n = 33) received no G4G intervention (group 1 or 2) conditions and were expected to carry out their usual LGF community sports activities. Primary outcome measurements (at both pre- and 10-week follow up) examining the effectiveness of the G4G intervention included (1) PA, (2) FMS and (3) Psychological correlates (enjoyment levels, self-efficacy, peer and parental support). Following a two (pre to post) by three (intervention group 1, intervention group 2, and control group 3) mixed-model ANOVA, it was highlighted that intervention group 1 significantly increased in PA (p = 0.003), FMS proficiency (p = 0.005) and several psychological correlates of PA (p ≤ 0.005). The findings demonstrate that the 10-week, specifically tailored, research-informed G4G intervention is a feasible and efficacious program, leading to a positive effect on the physical and psychological wellbeing of pre-adolescent Irish girls, relative to the traditionally delivered national G4G comparative program and control group conditions.

Intervention Effects of "Girls on the Move" on Increasing Physical Activity: A Group Randomized Trial

BACKGROUND

Limited intervention success in increasing and sustaining girls' moderate-to-vigorous physical activity (MVPA) underscores a need for continued research.

PURPOSE

The aim of this study was to evaluate the effect of a 17-week Girls on the Move (GOTM) intervention on increasing MVPA among fifth- to eighth-grade girls.

METHODS

This study is a group (cluster) randomized trial, including 24 schools, pair matched and assigned to intervention (n = 12) or control (n = 12) conditions. Participants included 1,519 girls in racially diverse public schools in urban, underserved areas of the Midwestern USA. The intervention included three components: (i) 90-min after-school physical activity (PA) club offered 3 days/week; (ii) two motivational, individually tailored counseling sessions; and (iii) an interactive Internet-based session at the midpoint of the intervention. Main outcome measures were weighted mean minutes of MVPA per week post-intervention and at 9-month follow-up measured via accelerometer.

RESULTS

No between-group differences occurred for weighted mean minutes of MVPA per week at post-intervention (B = -0.08, p = .207) or 9-month follow-up (B = -0.09, p = .118) while controlling for baseline MVPA.

CONCLUSIONS

Research is needed to identify interventions that assist girls in attaining and maintaining adequate PA.

CLINICALTRIALS.GOV IDENTIFIER

NCT01503333.

Attending After-School Physical Activity Club 2 Days a Week Attenuated an Increase in Percentage Body Fat and a Decrease in Fitness Among Adolescent Girls at Risk for Obesity

PURPOSE

To evaluate the effect of a 17-week intervention, including an after-school physical activity (PA) club 3 d/wk, on moderate-to-vigorous physical activity (MVPA), body mass index (BMI) z score, percentage body fat (%BF), and cardiorespiratory fitness (CRF) among fifth to eighth grade girls having a BMI z score ≥0, and explore whether intervention outcomes varied by club attendance (1 vs 2 vs 3 d/wk).

DESIGN

Secondary analysis of data from a group randomized controlled trial (N = 1519, 10- to 15-year-old girls: n = 753 intervention; n = 766 control).

SETTING

Twenty-four Midwestern US schools (n = 12 intervention; n = 12 control).

SAMPLE

Subsample (n = 1194 girls) from trial's intervention (n = 593 girls) and control (n = 601 girls) groups having BMI z scores ≥0.

MEASURES

Moderate-to-vigorous physical activity (min/h), BMI z score, %BF, and CRF (V ˙ O 2max : mL/kg/min) were estimated at baseline and postintervention.

ANALYSIS

Linear mixed-effect models.

RESULTS

Intervention group gained less %BF (B = -0.35, P = .016), and their CRF decreased less (B = 0.22, P = .010) than the control. Marginally significant findings showed girls attending the club an average of 1 d/wk had greater increases in %BF (B = 0.33, P = .087) and MVPA (B = 0.20, P = .083) and a greater decrease in CRF (B = -0.20, P = .061) than girls attending 3 d/wk. No differences occurred between girls who attended 2 versus 3 d/wk for any outcomes.

CONCLUSIONS

The intervention attenuated an increase in %BF and a decrease in CRF among girls at risk for obesity from baseline to postintervention. Offering the after-school PA club 2 d/wk may be adequate for achieving outcomes.

Mediators of Physical Activity Behavior Change in the "Girls on the Move" Intervention

BACKGROUND

The minimal effect of interventions to date on increasing young adolescent girls' physical activity (PA) may be due to inadequate understanding of the mechanisms underlying behavior change, yet sparse research testing a PA intervention has examined the capacity of theories to explain PA, particularly when using objective measures.

OBJECTIVES

The aim of the study was to examine whether constructs from the health promotion model and self-determination theory mediated changes in moderate-to-vigorous physical activity (MVPA) following a 17-week intervention.

METHODS

The study was a secondary analysis of data from a group randomized trial, including 12 intervention and 12 control schools in the Midwestern United States. Data were collected in 2012-2016. Girls (fifth- to eighth-grade, N = 1,519) completed surveys on perceived benefits and enjoyment of PA, PA self-efficacy, social support and motivation for PA, and barriers to PA and wore accelerometers.

RESULTS

The final path model had a good fit: χ(4) = 2.48, p = .648; goodness-of-fit index = 1; comparative fit index = 1; root-mean-square error of approximation = 0; standardized root-mean-square residual = 0.01. For MVPA change from baseline to postintervention, enjoyment (B = 24.48, p < .001) and social support (B = 30.48, p < .001) had a positive direct effect, whereas the intervention had a positive indirect effect through enjoyment and social support (B = 9.13, p < .001). Enjoyment (B = -13.83, p < .001) and social support (B = -17.22, p < .001) had a negative indirect effect on MVPA change from postintervention to follow-up.

DISCUSSION

Enjoyment of PA and social support for PA may be important mediators of PA in young adolescent girls and warrant consideration when designing interventions.

Walking Green: Developing an Evidence Base for Nature Prescriptions

Although the health benefits of exercise and exposure to nature are well established, most evidence of their interaction comes from acute observations of single sessions of activity. However, documenting improved health outcomes requires ongoing interventions, measurement of multiple outcomes, and longitudinal analyses. We conducted a pilot study to guide the development of a protocol for future longitudinal studies that would assess multiple physiological and psychological outcomes. Herein, we report psychological outcomes measured from thirty-eight participants before and after three conditions: a 50 min walk on a forest path, a 50 min walk along a busy road, and a period of activities of daily living. Changes in positive and negative affect, anxiety, perceived stress, and working memory are reported. We benchmark these results to existing studies that used similar protocols and also identify elements of the protocol that might impair recruitment or retention of subjects in longer-term studies. Linear mixed-models regression revealed that walking improved psychological state when compared to activities of daily living, regardless of walk environment (p < 0.05). Comparison of mean differences showed that forest walks yielded the largest and most consistent improvements in psychological state. Thus, despite a protocol that required a 3.5 h time commitment per laboratory visit, the beneficial effects of walking and exposure to a forested environment were observed.

Effects of the Girls on the Move randomized trial on adiposity and aerobic performance (secondary outcomes) in low-income adolescent girls

BACKGROUND

Limited, mixed evidence exists regarding the effectiveness of physical activity interventions on adiposity and aerobic performance in adolescent underrepresented populations.

OBJECTIVE

To examine effects of Girls on the Move on body mass index z-scores (BMI-z), percent (%) body fat, and aerobic performance in fifth- to eighth-grade underrepresented girls.

METHODS

A group randomized trial, involving 12 intervention and 12 control schools in low-income areas, was conducted. Participants (n = 1519) were low-active girls. The 17-week intervention included (a) a physical activity club, (b) two motivational interviewing sessions, and (c) one Internet-based session. BMI-z was determined from measured height and weight; % body fat was assessed using bioelectric impedance. Aerobic performance was assessed using a shuttle run. Demographics, physical activity (accelerometer), and pubertal development were assessed. Linear mixed models, adjusting for baseline, were used to examine group differences in postintervention.

RESULTS

No significant between-group differences in BMI-z existed at postintervention, but % body fat increased less among intervention than control group girls (Mchange = 0.43% vs 0.73%). Aerobic performance decreased less in intervention vs control (Mchange = -0.39 vs -0.57).

CONCLUSIONS

Although the intervention positively impacted % body fat and aerobic performance in underrepresented girls, more research is necessary to determine optimal implementation for yielding greater effects.

Cardiorespiratory Fitness as a Mediator of the Association between Physical Activity and Overweight and Obesity in Adolescent Girls

Background: Overweight and obesity (OW/OB) continue to be prominent health issues among adolescent girls. However, little is known about the interrelationships between physical activity (PA), cardiorespiratory fitness (CRF), and OW/OB in this population. The objective of this study was to examine whether CRF mediates the relationship between PA and OW/OB in adolescent girls. Methods: Moderate-to-vigorous PA (MVPA), CRF, BMI, and percentage body fat (% BF) were measured in adolescent girls (N = 1519), aged 10-14 years, from 24 urban middle schools located in the Midwestern United States. Structural equation modeling was used to determine whether CRF is a mediator of the association between MVPA and OW/OB (measured as both BMI and % BF). Multigroup analyses were used to determine whether race, puberty, or socioeconomic status moderate the mediation models. Results: The indirect effect of MVPA through CRF on OW/OB was significant for both BMI (p < 0.01) and % BF (p < 0.01), indicating that CRF is a complete mediator between MVPA and OW/OB. Both race and puberty significantly (p < 0.05) moderated the mediation between MVPA and OW/OB. Conclusions: This study demonstrates that CRF is improved by increasing MVPA, and the improvement in CRF results in lower BMI and % BF among adolescent girls.

Predicting physical activity among urban adolescent girls: A test of the health promotion model

The purpose of this study was to test hypothesized relationships of the health promotion model (HPM) as a means of predicting moderate-to-vigorous physical activity (MVPA) among urban, adolescent girls. A secondary analysis of baseline data from a group randomized controlled trial was conducted. The study involved eight urban schools in the Midwestern United States. The sample included girls (N = 517) in the 5th-8th grades. Data were collected on age, body mass index, pubertal status, enjoyment, self-efficacy, social support, options for physical activity (PA), and commitment to PA. MVPA was measured via accelerometers worn by the girls for 7 days. Structural equation modeling was used to analyze study aims. Mean age of the sample was 11.8 years (standard deviation [SD] = 1.0). Girls attained an average of 3.0 (SD = 1.2) minutes per hour of MVPA. Self-efficacy had a positive direct (β = .337; p < .001) and total effect (β = .310; p < .001) on MVPA. Social support and options for PA were not significant predictors of commitment to PA or MVPA. Commitment to PA had a negative but nonsignificant effect (β = -.056; p = .357) on MVPA. The model predicted 10.1% of the variance in MVPA with 9.6% of the variance predicted by self-efficacy. Limitations include lack of longitudinal analysis and inability to generalize the results to other populations such as boys. PA self-efficacy continues to emerge as a significant predictor of MVPA in the HPM. Continued theory testing is needed to better understand the correlates and determinants of PA among adolescent girls before designing theory-based interventions to promote PA.

Impact of Short Message Service (SMS) Education Based on a Health Promotion Model on the Physical Activity of Patients with Type II Diabetes

INTRODUCTION

Physical activity is the most important self-management behaviour in diabetes. The aim of this study was to evaluate the impact of a short message service (SMS) based on a health promotion model (HPM) on the physical activity of diabetic patients.

METHODS

This quasi-experimental study consisted of 37 type II diabetes patients in an SMS group and 36 type II diabetes patients in a control group. The patients in both groups completed written consent forms and questionnaires at the beginning of the study. The patients in the SMS group received training messages within two weeks (two or three messages daily) in the field of physical activity based on HPM constructs. Both groups completed questionnaires in three stages (at the beginning of the study, four weeks after the first visit, and three months later) comprising demographic factors, questions regarding the constructs, and 7-day physical activity recall. After data collection, statistical analysis was conducted using an independent t-test, a Chi-square test, and a repeated measures analysis of variance (ANOVA).

RESULTS

As compared with the control group, changes in mean scores of perceived self-efficacy (P = 0.001) and family support (P = 0.046) of physical activity in the training group were significantly greater and perceived barriers (P < 0.001) were significantly lower over time. The physical activity performance of the SMS group was better three months after training as compared with that of the control group (P < 0.001).

CONCLUSION

The results demonstrated the efficacy of training messages in changing the beliefs and physical activity behaviours of diabetic patients.

The effects of health promotion model-based educational program on self-care behaviors in patients undergoing coronary artery bypass grafting in Iran

Background and aim

Post-operative self-care behaviors, have positive effects on increase in adaptability, and reduce cardiac surgery patients’ disability. The present study is carried out aimed at determining the effect of education based on a health promotion model on the patients’ self-care behaviors after coronary artery bypass surgery.

Methods

This is a semi-experimental study carried out in Mazandaran (Iran) in 2016. Two hundred and twenty patients who participated in the study were selected using a simple random sampling method from a population of postoperative patients, and divided into control and experimental groups (110 patients in each) using block (AABB) randomization. Self-designed self-care questionnaires based on a health promotion model were distributed among the patients once before and three months after intervention. The data were analyzed by SPSS-22, Chi-Square tests, Mann-Whitney and ANCOVA at the significance level of p<0.05.

Results

The average score of total self-care behaviors in cardiac surgery patients was not significant between the two groups before education (p=0.065), but after training, a significant difference was observed between the two groups (p<0.001). The analysis of ANOVA with repeated measure indicated that following the intervention, significant difference was observed between the two groups in terms of improvement of self-care behaviors after excluding the effect of pre-test and controlling demographic and health-related characteristics.

Conclusions

Developing and implementing a training program based on the health promotion model can enhance self-care behaviors and reduce the number of admissions in patients after cardiac surgery.

Sources and Types of Social Support for Physical Activity Perceived by Fifth to Eighth Grade Girls

BACKGROUND

Information is lacking on forms and sources of social support for physical activity (PA) received by adolescent girls during various pubertal stages. Two study purposes were to (a) identify the sources and forms of social support for PA perceived by adolescent girls, and (b) examine associations of pubertal stage and social support with PA.

METHODS

A secondary analysis of data from a randomized trial was conducted. Fifth through eighth grade girls (N = 1,519) completed surveys on social support for PA and pubertal stage and wore an accelerometer.

RESULTS

Girls in early-middle and late-post puberty most frequently received social support from their mothers. A higher proportion of girls in late-post puberty, compared to early-middle puberty, received social support from nonfamily adults (4.2% vs. 3.0%, p = .019). Girls identifying three sources participated in more moderate-to-vigorous PA than those having fewer sources (t_1,512 = -3.57, p < .001). Various forms of social support, except for encouragement, were positively related to moderate-to-vigorous PA. Girls in early-middle puberty reported greater social support than those in late-post puberty (t_1,512 = 3.99, p < .001). Social support was positively associated with moderate-to-vigorous PA, while girls in late-post puberty had lower moderate-to-vigorous PA than those in early-middle puberty.

CONCLUSIONS

Mothers are important sources of social support for PA. Having more than two sources may result in greater PA. Encouraging girls to increase their PA may not be sufficient.

CLINICAL RELEVANCE

Efforts are needed from health professionals to prevent any decline in social support for PA as girls advance across adolescence.

Demographic differences in and correlates of perceived body image discrepancy among urban adolescent girls: a cross-sectional study

Background

Understanding factors related to girls’ body image discrepancy, which is the difference between self-perceived current or actual and ideal body size, is important for addressing body-related issues and preventing adverse sequelae. Two aims were to: 1) examine demographic differences in body image discrepancy; and 2) determine the association of body image discrepancy with weight status, percent body fat, physical activity, sedentary behavior, and cardiovascular (CV) fitness among young adolescent girls.

Methods

The cross-sectional study included a secondary analysis of baseline data from a group randomized controlled trial including 1519 5th–8th grade girls in 24 U.S. schools. Girls completed physical activity and sedentary behavior surveys. To indicate perceived current/actual and ideal body image, girls selected from nine body figures the one that represented how they look now and another showing how they want to look. Girls wore accelerometers measuring physical activity. Height, weight, and percent body fat were assessed. The Progressive Aerobic CV Endurance Run was used to estimate CV fitness. Independent t-test, one- and two-way ANOVA, correlational analyses, and hierarchical linear regressions were performed.

Results

The majority (67.5%; n = 1023) chose a smaller ideal than current/actual figure. White girls had higher body image discrepancy than Black girls (p = .035). Body image discrepancy increased with increasing weight status (F_3,1506 = 171.32, p < .001). Moderate-to-vigorous physical activity (MVPA) and vigorous physical activity were negatively correlated with body image discrepancy (r = −.10, p < .001; r = −.14, p < .001, respectively), but correlations were not significant after adjusting for race and body mass index (BMI), respectively. Body image discrepancy was moderately correlated with CV fitness (r = −.55, p < .001). After adjusting for demographics, percent body fat, but not CV fitness or MVPA, influenced body image discrepancy. Girls with higher percent body fat had higher body image discrepancy (p < .001).

Conclusion

This study provided important information to guide interventions for promoting a positive body image among girls.

Trial registration

ClinicalTrials.gov Identifier NCT01503333, registration date: January 4, 2012.

Physical Activity Among Female Adolescents in Jeddah, Saudi Arabia: A Health Promotion Model-Based Path Analysis

BACKGROUND

In Saudi Arabia, about 14.8% of female children and adolescents of less than 20 years old are obese, compared with only 9.4% of male children and adolescents. One major factor linked to the high prevalence of obesity and related chronic illnesses involves inadequate physical activity (PA). Only 25% of female adolescents in Saudi Arabia meet the recommendation calling for 60 minutes of moderate to vigorous PA per day.

OBJECTIVE

The aim of this research was to examine relationships among self-reported PA and cognitive and affective variables, including perceived barriers to PA, PA self-efficacy, enjoyment of PA, social support for PA, and commitment to PA.

METHODS

Female Saudi adolescents 13-18 years of age were recruited from 10 public intermediate and high schools in Jeddah, Saudi Arabia. Female adolescents who met the inclusion criteria completed surveys and participated in height and weight measurements at schools. A structural equation model based on the health promotion model was estimated, with commitment to PA hypothesized to mediate relationships between health promotion model (HPM) predictors and self-reported PA.

RESULTS

A total of 405 female adolescents with a mean age of 15.4 years took part in the study, of whom 25.3% were overweight or obese. Mean PA level measured via the Physical Activity Questionnaire for Adolescents was 2.1 (SD = 0.66), which is low. Commitment to PA partially mediated the relationships of PA self-efficacy, enjoyment of PA, and social support for PA; 25.4% of the variance in PA was explained. The model did not support the indirect relationship of perceived barriers through commitment or the direct relationship between enjoyment and PA.

DISCUSSION

This study indicates that Saudi female adolescents are in need of interventions to increase their PA. The findings suggest that addressing perceived barriers to PA and targeting PA self-efficacy, enjoyment of PA, and social support for PA to enhance commitment to PA may be a fruitful approach in nursing interventions to increase PA among Saudi female adolescents.

Comparing the Psychometric Properties of Two Physical Activity Self-Efficacy Instruments in Urban, Adolescent Girls: Validity, Measurement Invariance, and Reliability

Aims: This study compared the psychometric properties of two self-efficacy instruments related to physical activity. Factorial validity, cross-group and longitudinal invariance, and composite reliability were examined. Methods: Secondary analysis was conducted on data from a group randomized controlled trial investigating the effect of a 17-week intervention on increasing moderate to vigorous physical activity among 5th-8th grade girls (N = 1,012). Participants completed a 6-item Physical Activity Self-Efficacy Scale (PASE) and a 7-item Self-Efficacy for Exercise Behaviors Scale (SEEB) at baseline and post-intervention. Confirmatory factor analyses for intervention and control groups were conducted with Mplus Version 7.4 using robust weighted least squares estimation. Model fit was evaluated with the chi-square index, comparative fit index, and root mean square error of approximation. Composite reliability for latent factors with ordinal indicators was computed from Mplus output using SAS 9.3. Results: Mean age of the girls was 12.2 years (SD = 0.96). One-third of the girls were obese. Girls represented a diverse sample with over 50% indicating black race and an additional 19% identifying as mixed or other race. Both instruments demonstrated configural invariance for simultaneous analysis of cross-group and longitudinal invariance based on alternative fit indices. However, simultaneous metric invariance was not met for the PASE or the SEEB instruments. Partial metric invariance for the simultaneous analysis was achieved for the PASE with one factor loading identified as non-invariant. Partial metric invariance was not met for the SEEB. Longitudinal scalar invariance was achieved for both instruments in the control group but not the intervention group. Composite reliability for the PASE ranged from 0.772 to 0.842. Reliability for the SEEB ranged from 0.719 to 0.800 indicating higher reliability for the PASE. Reliability was more stable over time in the control group for both instruments. Conclusions: Results suggest that the intervention influenced how girls responded to indicator items. Neither of the instruments achieved simultaneous metric invariance making it difficult to assess mean differences in PA self-efficacy between groups.

Effectiveness of a Playground Intervention for Antisocial, Prosocial, and Physical Activity Behaviors

BACKGROUND

We examined the effectiveness of Peaceful Playgrounds™ (P2) to decrease antisocial behaviors (ASB) while increasing physical activity (PA) and prosocial behaviors (PSB) in elementary school children.

METHODS

A longitudinal, cluster-randomized design was employed in 4 elementary school playgrounds where students (third to fifth) from 2 intervention and 2 control schools were observed during recess periods. The intervention included environmental changes (eg, marked surfaces) and student education. Data were collected using systematic observations of youth behavior and semistructured interviews conducted with key informants. Mixed-effects regression models controlling for scans nested within days nested within schools estimated the interaction of measurement period and treatment condition on children's PA, PSB, and ASB. It was hypothesized that children in intervention, but not control schools, would demonstrate increased PA/PSB and decreased ASB.

RESULTS

Contrary to the hypotheses, intervention and control schools showed favorable changes for all dependent variables except for PSB, but 1 intervention and 1 control school drove these effects. Follow-up interviews indicated variability in implementation and lack of adherence to the control condition.

CONCLUSIONS

P2 may promote increased PA during recess, but these results demonstrate the complexity of intervention implementation and the need for rigor when measuring intervention fidelity in real-world settings.

Psychometric Evaluation of Three Psychosocial Measures Associated With Physical Activity Among Adolescent Girls

The purpose of this study was to evaluate the psychometric properties of a Perceived Benefits Scale, a Perceived Barriers Scale, and a Physical Activity Enjoyment Scale with data from a group randomized controlled trial (RCT) and a test-retest study with 1-week interval. In the group RCT at baseline and Week 17, 1,012 fifth- to eighth-grade girls completed an iPad-delivered survey and wore 7-day accelerometers measuring moderate-to-vigorous physical activity (MVPA). In the test-retest study, 91 fifth- to seventh-grade girls completed the iPad-delivered survey at Times 1 and 2. Benefits, barriers, and enjoyment scales had Cronbach's αs of .75, .86, and .78 and test-retest reliability of .83, .88, and .79, respectively. Benefits Scale had a two-factor structure (physical and psychosocial benefits), while the remaining two had a one-factor structure indicating construct validity. Barriers ( r = -.16) and enjoyment ( r = .17) were correlated with MVPA indicating concurrent validity. Baseline MVPA and psychosocial benefits positively, while physical benefits negatively, predicted MVPA at Week 17 indicating predictive validity. The measures demonstrated satisfactory psychometric properties.

Evaluating Mailed Motivational, Individually Tailored Postcard Boosters for Promoting Girls' Postintervention Moderate-to-Vigorous Physical Activity

BACKGROUND

Ways to optimize boosters to assist girls to attain adequate moderate-to-vigorous physical activity following an intervention are unknown.

OBJECTIVE

This study's purpose was to (a) determine whether girls receiving mailed motivational, individually tailored postcard boosters following a 17-week physical activity intervention would have greater moderate-to-vigorous physical activity at 9-month follow-up as compared to girls not receiving them and those in a control group and (b) evaluate girls' perceptions of the booster intervention.

METHODS

Sixth to seventh grade girls (n = 117) from two urban, Midwest schools with similar demographic characteristics participated in a 17-week physical activity intervention, and girls from a third school served as controls (n = 64). One (n = 54) of the two intervention schools was randomly assigned to receive 13 motivational, individually tailored postcards containing messages to encourage them to attain adequate physical activity during the postintervention period. Girls from the other intervention school (n = 63) did not receive postcards, and those in the control school did not receive any intervention. Moderate-to-vigorous physical activity was measured with accelerometers at postintervention and 9-month follow-up. Girls completed a postcard evaluation survey at 9-month follow-up.

RESULTS

Moderate-to-vigorous physical activity decreased significantly from postintervention to 9-month follow-up with no between-group differences or group-by-time interaction effect. On the basis of the survey, 27 (64.3%) girls received all postcards. Only 15 (35.7%) read all that they had received. Evaluations of postcards tended to be favorable.

DISCUSSION

Mailed booster postcards to promote physical activity among girls' postintervention were not effective. Strategies to achieve this objective warrant investigation.

Examining reach, dose, and fidelity of the "Girls on the Move" after-school physical activity club: a process evaluation

Background

After-school programs represent a promising opportunity to assist adolescent girls’ in attaining adequate physical activity. Although evaluating the process of intervention implementation is important for determining if an intervention was delivered and received as intended, comprehensive information about process evaluation methods and results are rarely reported. The purpose of this article was to evaluate the reach, dose, and fidelity of a 90-minute after-school physical activity club offered 3 days a week. The club is 1 of 3 components included in a 17-week intervention designed for 5th-8th grade girls, the majority of whom were of minority and/or low socioeconomic status.

Methods

A total of 24 schools (12 intervention; 12 control) and 56–67 girls per school (total N = 1519 girls) were included in the Girls on the Move group randomized controlled trial. At the beginning of each of 3 academic years (2012–2015), 8 schools per year were randomized to receive either the intervention (n = 4) or control condition (n = 4). To evaluate the club, data collected via surveys from girls, club coaches and managers, and process evaluators were analyzed. To evaluate the opportunity for physical activity provided by the coaches and managers, process evaluators used an observation tool based on the System for Observing Fitness Instruction Time and Academic Learning Time - Physical Education. Girls wore accelerometers every other week during the club time.

Results

Mean attendance was 41 % with the average attendance in year 3 being higher than rates for years 1 or 2. Mean moderate-to-vigorous physical activity time was 21.85 minutes measured via accelerometry and 21.81 minutes observed by process evaluators. Satisfaction with the intervention was high. For the most part, process evaluators perceived the club was delivered as planned and reflected constructs of the Health Promotion Model and Self-Determination Theory. Areas contributing to success included using incentives and offering a variety of activities. Issues negatively impacting implementation included managing behavioral problems, having limited space for moderate-to-vigorous physical activity, dealing with inclement weather, and getting coaches to actively participate in all physical activities with the girls.

Conclusions

This process evaluation provides important information to guide future school-based physical activity intervention delivery. Barriers to implementation have been identified. Ways to overcome them warrant consideration when designing physical activity interventions. Research is needed to test innovative approaches for enhancing attendance and increasing girls’ moderate-to-vigorous physical activity in after-school programs.

Trial registration

ClinicalTrials.gov Identifier NCT01503333. Registered 23 December, 2011.

Predictors of Health-Promoting Behaviors in Coronary Artery Bypass Surgery Patients: An Application of Pender's Health Promotion Model

Background

Advances in coronary artery surgery have reduced patient morbidity and mortality. Nevertheless, patients still have to face physical, psychological, and social problems after discharge from hospital.

Objectives

The objective of this study was to determine the efficacy of Pender’s health promotion model in predicting cardiac surgery patients’ lifestyles in Iran.

Methods

This cross-sectional study comprised 220 patients who had undergone coronary artery bypass graft (CABG) surgery in Mazandaran province (Iran) in 2015. The subjects were selected using a simple random sampling method. The data were collected via (1) the health-promoting lifestyle profile II (HPLP II) and (2) a self-designed questionnaire that included two main sections: demographic characteristics and questions based on the health-promoting model constructs.

Results

Spiritual growth (28.77 ± 5.03) and physical activity (15.79 ± 5.08) had the highest and lowest scores in the HPLP II dimensions, respectively. All the health promotion model variables were significant predictors of health-promoting behaviors and explained 69% of the variance in health-promoting behaviors. Three significant predictors were estimated using regression coefficients: behavioral feelings (β = 0.390, P < 0.001), perceived benefits (β = 0.209, P < 0.001), and commitment to a plan of action (β = 0.347, P < 0.001).

Conclusions

According to the results of the study, health-promoting model-based self-care behaviors can help identify and predict cardiac surgery patients’ lifestyles in Iran. This pattern can be used as a framework for discharge planning and the implementation of educational interventions to improve the lifestyles of CABG patients.

Cardiorespiratory fitness in urban adolescent girls: associations with race and pubertal status

Cardiorespiratory fitness affords health benefits to youth. Among females, weight-relative fitness declines during puberty and is lower among African American (AA) than Caucasian girls. Data indicate racial differences in pubertal timing and tempo, yet the interactive influence of puberty and race on fitness, and the role of physical activity (PA) in these associations have not been examined. Thus, independent and interactive associations of race and pubertal development with fitness in adolescent girls, controlling for PA were examined. Girls in grades 5-8 (n = 1011; Caucasian = 25.2%, AA = 52.3%, Other Race group = 22.5%) completed the Pubertal Development Scale (pubertal stage assessment) and Fitnessgram® Progressive Aerobic Cardiovascular Endurance Run (PACER) test (cardiorespiratory fitness assessment). PA was assessed by accelerometry. Bivariate and multivariate analyses were used to examine associations among race, pubertal stage and fitness, controlling for vigorous PA, AA, and pubertally advanced girls demonstrated lower fitness than Caucasian and less mature counterparts. Puberty and race remained significantly associated with fitness after controlling for vigorous PA. The interaction effect of race and puberty on fitness was non-significant. The pubertal influence on fitness is observed among AA adolescents. Associations between fitness and race/puberty appear to be independent of each other and vigorous PA. Pubertally advanced AA girls represent a priority group for fitness interventions.

Biological and Sociocultural Differences in Perceived Barriers to Physical Activity Among Fifth- to Seventh-Grade Urban Girls

BACKGROUND

Inadequate physical activity (PA) contributes to the high prevalence of overweight and obesity among U.S. adolescent girls. Barriers preventing adolescent girls from meeting PA guidelines have not been thoroughly examined.

OBJECTIVES

The threefold purpose of this study was to (a) determine pubertal stage, racial/ethnic, and socioeconomic status (SES) differences in ratings of interference of barriers to PA; (b) examine relationships between perceived barriers and age, body mass index, recreational screen time, sedentary activity, and PA; and (c) identify girls' top-rated perceived barriers to PA.

METHODS

Girls (N = 509) from eight Midwestern U.S. schools participated. Demographic, pubertal stage, perceived barriers, and recreational screen time data were collected via surveys. Height and weight were measured. Accelerometers measured sedentary activity, moderate-to-vigorous PA (MVPA), and light plus MVPA.

RESULTS

Girls of low SES reported greater interference of perceived barriers to PA than those who were not of low SES (1.16 vs. 0.97, p = .01). Girls in early/middle puberty had lower perceived barriers than those in late puberty (1.03 vs. 1.24, p < .001). Girls' perceived barriers were negatively related to MVPA (r = -.10, p = .03) and light plus MVPA (r = -.11, p = .02). Girls' top five perceived barriers included lack of skills, hating to sweat, difficulty finding programs, being tired, and having pain.

DISCUSSION

Innovative interventions, particularly focusing on skill development, are needed to assist girls in overcoming their perceived barriers to PA.

Social support and peer norms scales for physical activity in adolescents

OBJECTIVES

To evaluate psychometric properties of a Social Support and Peer Norms Scale in 5th-7th grade urban girls.

METHODS

Baseline data from 509 girls and test-retest data from another 94 girls in the Midwestern US were used.

RESULTS

Cronbach's alpha was .83 for the Social Support Scale and .72 for the Peer Norms Scale, whereas test-re-test reliability was .78 for both scales. Exploratory factor analysis suggested a single factor structure for the Social Support Scale, and a 3-factor structure for the Peer Norms Scale. Social support was correlated with accelerometer-measured physical activity (r = .13, p = .006), and peer norms (r = .50, p < .0001).

CONCLUSIONS

Both scales have adequate psychometric properties.

Do school-based physical activity interventions increase or reduce inequalities in health?

Little is known about the effectiveness of school-based health promotion on physical activity inequalities among children from low-income areas. This study compared the two-year change in physical activity among 10-11 year-old children attending schools with and without health promotion programs by activity level, body weight status, and socioeconomic backgrounds to assess whether health promotion programs reduce or exacerbate health inequalities. This was a quasi-experimental trial of a Comprehensive School Health (CSH) program implemented in schools located in socioeconomically disadvantaged neighbourhoods in Edmonton, Alberta, Canada. In the spring of 2009 and 2011, pedometer (7 full days) and demographic data were collected from cross-sectional samples of grade five children from 10 intervention and 20 comparison schools. Socioeconomic status was determined from parent self-report. Low-active, active, and high-active children were defined according to step-count tertiles. Multilevel linear regression methods adjusted for potential confounders were used to assess the relative inequity in physical activity and were compared between groups and over-time. In 2009, a greater proportion of students in the intervention schools were overweight (38% vs. 31% p = 0.03) and were less active (10,827 vs. 12,265 steps/day p < 0.001). Two years later, the relative difference in step-counts between intervention and comparison schools reduced from -15.5% to 0% among low-active students, from -13.4% to 0% among active students, and from -15.1% to -2.7% among high-active students. The relative difference between intervention and comparison schools reduced from -11.1% to -1.6% among normal weight students, from -16.8% to -1.4% among overweight students, and was balanced across socioeconomic subgroups. These findings demonstrate that CSH programs implemented in socioeconomically disadvantaged neighbourhoods reduced inequalities in physical activity. Investments in school-based health promotion are a viable, promising, and important approach to improve physical activity and prevent childhood obesity, and may also reduce inequalities in health.