A systematic review of intervention effects on potential mediators of children's physical activity

Effects of the DAGIS randomized controlled trial on home environment and children's food consumption according to the degree of implementation

BACKGROUND

Combining process evaluation data with effectiveness data and examining the possible mediators of intervention effects elicits valuable knowledge about how and for whom these interventions are effective. The aim of this study was to examine whether the parental degree of implementation (DOI) of a home-involving preschool intervention affected children's food consumption via home mediators.

METHODS

The five-month Increased Health and Wellbeing in Preschools (DAGIS) intervention involved 476 participating children aged 3-6 years and was conducted in 2017-2018. Parents reported children's food consumption (g/day) outside childcare hours, the availability of foods at home, role modelling of food consumption, and the norms related to food consumption. In addition, parents reported the extent to which they had implemented the intervention program at home. Mediation analyses were conducted to examine the effect of low and high DOI compared to control group on the change in children's consumption of fruit and vegetables (FV), sugary everyday foods, sugary treats, and sugar-sweetened beverages (SSB) via food availability in the home, parental role modelling and parental norms.

RESULTS

Compared to the control group, there was a direct effect of a high DOI on diminishing consumption of SSB (B -27.71, 95% CI -49.05, -4.80). No indirect effects were detected. In the high DOI group, a change in parental norm was associated with increased FV consumption showing an indirect effect (B 4.31, 95% CI 0.23, 10.59). In the low DOI group, there was an indirect effect via decreased food availability leading to decreased sugary everyday food consumption (B -2.17, 95% CI -5.09,  -0.09).

CONCLUSIONS

Combining process evaluation and effectiveness data revealed a decrease in children's SSB consumption only in the high DOI group, as well as indirect effects on children's consumption of FV and sugary everyday foods. In order to gain more intervention effects, further studies are required in order to examine parental facilitators and barriers to the implementation of interventions and how to impact effectively the determinants of the targeted behavior.

TRIAL REGISTRATION

ISRCTN57165350 (8 January, 2015).

Mediators of Effects on Physical Activity and Sedentary Time in an Activity Tracker and Behavior Change Intervention for Adolescents: Secondary Analysis of a Cluster Randomized Controlled Trial

Background

Adolescence is a critical age where steep declines in physical activity and increases in sedentary time occur. Promoting physical activity should therefore be a priority for short- and long-term health benefits. Wearable activity trackers in combination with supportive resources have the potential to influence adolescents’ physical activity levels and sedentary behavior. Examining the pathways through which such interventions work can inform which mediators to target in future studies.

Objective

The aim of this paper is to examine the impact of the Raising Awareness of Physical Activity (RAW-PA) intervention on potential mediators of behavior change after intervention, and whether these mediated the intervention effects on physical activity and sedentary time at 6-month follow-up.

Methods

RAW-PA was a 12-week intervention, grounded in social cognitive theory and behavioral choice theory, aimed at increasing physical activity among inactive adolescents through combining a wearable activity tracker with digital resources delivered via a private Facebook group (n=159 complete cases). The targeted potential mediators were identified from previous studies conducted in adolescents and included self-efficacy, peer support, family support, teacher support, self-regulation strategies, barriers, and enjoyment. Outcomes included sedentary time as well as light- and moderate-to-vigorous–intensity physical activity. A series of mixed linear models were used to estimate intervention effects on physical activity and sedentary behavior at follow-up and on potential mediators after intervention and to test whether there were indirect effects of the intervention on physical activity and sedentary behavior via mediators.

Results

Adolescents in the intervention group (n=75) engaged in higher sedentary time and lower light intensity at 6-month follow-up compared to the wait-list controls (n=84). There were no intervention effects for moderate-to-vigorous–intensity physical activity. The intervention group perceived more barriers to physical activity than the wait-list control group at 6-month follow-up (mean adjusted difference=1.77; 95% CI 0.19-3.34; P=.03). However, indirect effects for each outcome were not statistically significant, indicating that perceived barriers to physical activity did not mediate intervention effects for physical activity or sedentary time.

Conclusions

RAW-PA did not beneficially impact hypothesized mediators in these inactive adolescents, despite strategies being designed to target them. This suggests that the lack of overall intervention effects on physical activity and sedentary time observed in the RAW-PA study could be due to the limited impact of the intervention on the targeted mediators. Future studies should consider different strategies to target theoretically informed potential mediators and identify intervention strategies that effectively target key mediators to improve physical activity among inactive adolescents. Finally, intervention effects according to level of wearable tracker use or level of engagement with the intervention should be explored. This may provide important insights for designing successful wearable activity tracker interventions.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12616000899448; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370716&isReview=true

International Registered Report Identifier (IRRID)

RR2-10.1186/s12889-016-3945-5

Teacher Training and Engagement in Health Promotion Mediates Health Behavior Outcomes

School-based health promotion interventions have been shown to lead to measurable changes in the nutrition and physical activity behaviors. This study examines whether the impact of an intervention program on students’ healthy eating and physical activity was mediated by teacher training and engagement in health promotion. The trial was conducted in three phases: needs assessment of the baseline survey of teachers, mothers’ and children; intervention among seven randomly selected schools that included teacher training in healthy eating and physical activity; and a post-intervention evaluation survey. The SPSS PROCESS for Hayes (Model8) was used to determine moderation and mediation effects. The difference in difference (DID) was calculated for the three main outcomes of the study: eating breakfast daily (DID = 17.5%, p < 0.001); consuming the recommended servings of F&V (DID = 29.4%, p < 0.001); and being physically active for at least 5 days/week (DID = 45.2%, p < 0.001). Schoolchildren’s eating breakfast daily was mediated by their teachers’ training in nutrition (β = 0.424, p = 0.002), teachers’ engagement (β = 0.167, p = 0.036), and mothers preparing breakfast (β = 1.309, p < 0.001). Schoolchildren’s consumption of F&V was mediated by teachers’ engagement (β = 0.427, p = 0.001) and knowing the recommended F&V servings (β = 0.485, p < 0.001). Schoolchildren’s physical activity was mediated by their teachers’ training in physical activity (β = 0.420, p = 0.020) and teachers’ engagement (β = 0.655, p < 0.001). Health behavior changes in the school setting including improvements in eating breakfast, consuming the recommended F&V and physical activity was mediated by teacher training and engagement. Effective teacher training leading to teacher engagement is warranted in the design of health-promotion interventions in the school setting.

Adolescents' Physical Activity and Depressive Symptoms: A Psychosocial Mechanism

Guided by the Theory of Planned Behavior (TPB; Ajzen, 1991), this study aimed to test a hypothesized path model of TPB variables (i.e., attitude toward behavior, subjective norm, perceived behavioral control, and intention) with physical activity (PA) and depressive symptoms. A total of 792 Chinese adolescents (M_age = 16.9; SD = 0.82; 54.5% females) completed previously validated questionnaires assessing their TPB variables, PA, and depressive symptoms. Correlation analysis revealed TPB variables were positively associated with PA (p < 0.01), and negatively correlated to depressive symptoms (p < 0.01). The path analyses indicated that the hypothesized model produces a goodness of fit (χ²/df = 16.14/5, CFI = 0.99, RMSEA = 0.06). The findings support the theoretical tenets of TPB and provide empirical evidence of the psychosocial mechanism of PA and depressive symptoms in Chinese adolescents. It suggests that building PA intervention strategies while considering the TPB framework may promote adolescents' physical and mental health.

Mediators and moderators of physical activity changes in a school-based intervention targeting childhood obesity

This study identifies mediators and moderators of changes in physical activity (PA) following a school-based pilot intervention. Students from two Lebanese schools were randomly allocated into intervention (n = 191) and control (n = 183) groups. The multiple-mediation analysis revealed that active self-identity and perceived barriers mediated the intervention's effect on PA changes. Baseline intention, attitude, PBC, and age moderated PA changes at post-intervention. The youngest participants and those reporting the lowest PA scores at baseline benefited most from the intervention. Future interventions with students should target these mediators and moderators to promote positive change in PA behavior.

Compliance with a physical activity guideline among junior high school students

BACKGROUND

There were no nationwide moderate- to vigorous-intensity physical activity (MVPA) data relating to Japanese adolescents. This study assessed compliance with an MVPA guideline by adolescents, using a random sampling survey in Japan. The factors associated with compliance with the guideline were also examined.

METHODS

Participants were first- to third-grade Japanese junior high school students (307 boys and 255 girls). We analyzed data from the National Sports-Life Survey of Teens 2019, which used the Japanese version of physical activity (PA) questions in the World Health Organization Health Behavior in School-aged Children survey and potential correlates of MVPA.

RESULTS

Compliance with the PA guideline by the World Health Organization for Japanese students was 19.0% (95% confidence interval (CI), 15.8-22.3). The compliance of boys was significantly higher than that of girls (23.1%; 95% CI, 18.4-27.8; vs 14.1%; 95% CI, 9.8-18.4). The odds of meeting the PA guideline were significantly higher for boys in the second grade than boys in the first grade (odds ratio (OR) 1.78; 95% CI, 1.02-3.09), liking PA (for all: OR: 2.97; 95% CI, 1.32-6.69; for girls: OR: 2.99; 95% CI, 1.01-8.81), and sports participation (for all: OR: 4.77; 95% CI, 2.32-9.80; for boys: OR: 6.00; 95% CI, 1.81-19.89; for girls: OR: 4.08; 95% CI, 1.63-10.21).

CONCLUSIONS

The results suggest that more than 80% of junior high school students were insufficiently physically active in Japan. Preferences for PA and sports participation may be important correlates of sufficient PA.

Mediators between physical activity and academic achievement: A systematic review

BACKGROUND

Research has suggested the beneficial effects of physical activity (PA) on academic achievement (AA). However, the mechanisms underlying this influence remain unclear. Some proposed mechanisms include physiological, cognitive, psychological, and behavioral paths. This study aimed to analyze mediators between PA and AA in children and adolescents.

METHODS

Systematic search in Medline, SPORTDiscuss, PsycInfo, Scopus, and Web of Science for observational and experimental studies, published up to March 2021.

RESULTS

Twenty-eight studies (75237 participants, aged 4-16) were included. The designs of these studies were: 21 studies cross-sectional, 5 longitudinal, and 2 experimental. Eight out of nine studies analyzing fitness as a mediator reported positive results, and one reported null finding. Adiposity was a significant mediator in one study, in two only in girls, and two reported null results. Cognition as a mediator was supported by four studies, whereas two reported null results. Regarding mental well-being, 10 out of 14 studies reported positive effects, and one out of five behavioral studies found positive results. Although studies were too sparse to draw conclusions, overall, the results indicated that self-esteem, self-image, self-efficacy, stress, and health behaviors might be potential mediators in the relationship between PA and AA. All studies were rated as medium-high quality.

CONCLUSION

Overall, the available evidence seems to suggest that cardiorespiratory fitness, cognition, mental well-being, and exercise-related behaviors play some role as mediators of the relationship between PA and AA. However, the cross-sectional nature of most of the reviewed studies prevents us from making any statement in terms of causal paths. Thus, well-designed follow-up and randomized controlled studies aimed not only to tests the effect of PA in AA, but also to examine the influence of mediators are required.

It's Not Just What You Do but the Way You Do It: A Systematic Review of Process Evaluation of Interventions to Improve Gross Motor Competence

BACKGROUND

Motor competence is an important predictor of health behaviours. However, levels of motor competence are low in children and adolescents. Many interventions have improved motor competence, yet intervention effects were highly variable. Potential causes of such variations are not fully understood. Process evaluation can assist with the understanding of why an intervention worked or not, but its application and reporting in motor competence interventions has received little attention.

OBJECTIVES

The primary aim of this review was to investigate whether process evaluations have been reported in interventions to improve motor competence and, if reported, which process evaluation measures have been used. A secondary aim was to explore the association of intervention characteristics and process evaluation findings (outcomes of process evaluation measures) with intervention outcomes, in a search for what process evaluation measures may impact on intervention functioning and outcomes.

METHODS

The process of conducting and reporting this review adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The review protocol was registered with PROSPERO (CRD42019124412). A systematic search of seven electronic databases (i.e. MEDLINE [via EBSCOhost], Cochrane Central Register of Controlled Trials [CENTRAL], CINAHL, Academic Search Complete, Education Database, SPORTDiscus and Scopus) was conducted with no date restrictions. Eligibility criteria included the following: (1) a study sample of typically developing children and adolescents aged 5-18 years, (2) an intervention aimed to improve motor competence, (3) an intervention included a control group, (4) a report of motor competence outcome at both pre- and post-intervention. Only original articles published in English in peer-reviewed journals were considered. Process evaluation measures and findings were extracted using the UK Medical Research Council's process evaluation framework in order to provide overarching descriptions on the implementation, mechanism of change and context of interventions. Univariable meta-regressions were performed to ascertain whether selected study-level covariates moderated the improvement in motor competence outcomes in interventions.

RESULTS

The search identified 60 intervention studies. Only 30 studies (50%) reported process evaluation measures. No studies reported (or employed) theoretical frameworks to guide process evaluation. Process evaluation measures relating to implementation were most commonly reported, with the most prevalent aspect being fidelity. This was followed by reporting on measures relating to mechanism of change and context of the intervention. Meta-analysis results suggested intervention duration, dose, inclusion of process evaluation aim, provision of lesson plans, sample size and sex as potential moderators.

CONCLUSIONS

Reporting of process evaluation measures may help build our understanding of the optimal characteristics of motor competence interventions. However, process evaluation is under-used and/or under-reported. This review serves as a call for more process evaluations and better reporting in motor competence interventions.

How to Change Young Children's Physical Activity and Sedentary Behavior: Mechanisms of Behavior Change in the INFANT Cluster Randomized Controlled Trial

Background: Understanding the mechanisms (mediators) of behavior change is crucial to designing more effective interventions. However, this is rarely reported. This paper investigates the mechanisms that explain the lack of intervention effect on physical activity and the significant effect on television viewing time from an early childhood trial. Methods: Secondary analyses were undertaken of data from a cluster randomized controlled trial. The Melbourne Infant Feeding, Activity and Nutrition Trial (INFANT) was a 15-month group program promoting obesity-protective behaviors from the age of 4 months. Outcomes relevant to the current study were child physical activity (accelerometer), television viewing time (maternal report) and 12 potential mediator scales (maternal report). Linear regression models used the product of coefficients method with a joint significance test. Results: Complete data were from 398 mother-child dyads. Despite weak evidence of an intervention effect on the mother’s physical activity knowledge and optimism, there was no effect on children’s physical activity, and no clear mechanisms were identified. An intervention effect was observed for the mothers’ television knowledge (unstandardized regression coefficient for a path (a) = 0.34, 95% confidence interval (CI₉₅) = 0.22, 0.45), with weak evidence for maternal efficacy (a = 0.11, CI₉₅ = −0.02, 0.24) and the use of television (a = −0.10, CI₉₅ = −0.22, 0.01). The intervention impact on television knowledge explained 75% of the difference between the intervention and control groups in children’s television viewing. Conclusions: In the very early childhood period, as mothers are commencing their parenting journey, improving their behavioral knowledge appears to be the biggest contributor to reducing child television viewing, constituting a relatively simple strategy that could be implemented across clinical and public health settings. In contrast, it remains unclear what mechanisms may increase physical activity levels in this age group.

A health and wellbeing programme for preadolescents in underserved Australian communities: child and stakeholder perspectives

Social inequities in childhood affect children's health and development. Active In-Betweens is a weekly, healthy lifestyle and outdoor activity after-school programme, tailor-made for preadolescent children (9-12 year olds), incorporating a strengths-based, trauma-informed, co-designed and place-based approach. This study evaluated the extent to which the programme strategies and activities met the anticipated short- to medium-term programme outcomes during its first year of operation in two socio-economically disadvantaged housing communities in New South Wales, Australia. A qualitative case study used data from semi-structured interviews with child participants (n = 11) and key stakeholders (n = 10). A broad range of positive outcomes were described. Children's feedback indicated they had experienced opportunities which facilitated the development of new physical activity skills; new healthy eating experiences and knowledge; positive relationships with peers and facilitators and new connections with neighbourhood programmes and outdoor environments. Stakeholders valued the programme for the positive outcomes they observed among the children and the strong organizational partnerships which resulted. The importance of skilled facilitators to deliver the programme, the engagement of local stakeholders and a long-term commitment to programme delivery, with secure funding to ensure continuity, were clearly identified as integral for effective, sustainable outcomes.

Brief parental self-efficacy scales for promoting healthy eating and physical activity in children: a validation study

Background

Brief scales to measure parental self-efficacy (PSE) in relation to children’s obesogenic behaviours have not been developed and validated using more rigorous methodology such as invariance testing, limiting their generalisability to sub-groups.

This study aimed to assess the construct validity and measurement invariance of brief PSE scales for children’s intake of vegetables, soft drinks, and sweets, and physical activity.

Methods

Parents (n = 242) of five-to-seven-year-old children in disadvantaged and culturally diverse settings in Sweden responded to a questionnaire in Swedish with 12 items assessing PSE in relation to healthy and unhealthy behaviours. Construct validity was assessed with confirmatory factor analysis, invariance testing compared the scales by groups of parental sex, education, and child weight status. Criterion validity was evaluated using objective measures of children’s physical activity and semi-objective measures of diet.

Results

Two-factor models showed moderate to excellent fit to the data. Invariance was supported across all groups for healthy behaviour scales. Unhealthy behaviour scales were invariant for all groups except parental education where partial metric invariance was supported. Scales were significantly correlated with physical activity and diet.

Conclusion

This study provides preliminary evidence for the validity of brief PSE scales and invariance across groups suggesting their utility for research and clinical management of weight-related behaviours.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10581-7.

Predicting Family and Child Physical Activity across Six-Months of a Family-Based Intervention: An Application of Theory of Planned Behaviour, Planning and Habit

Family-based physical activity (PA) interventions have proven effective in modifying PA; yet, the underlying mechanisms are currently unclear. In this study, we follow-up upon prior trial data that showed changes to child moderate-to-vigorous PA (MVPA) as a result of a family education+planning intervention compared to an education-only condition. We examined parents' perceived family PA frequency, family PA social cognitions, and family PA habit over 26 weeks between the two conditions. One hundred and two parents (of children aged 6 to 12 yrs), were recruited through advertisements and randomized to either the planning + education condition (n = 52) or an education-only condition (n = 50). Self-reported family PA, and measures of theory of planned behaviour, planning intention, and habit were completed by the contact parent at baseline, six-week, 13-week, and 26-week time-periods. The education+planning intervention increased planning intention (p <.01) and family PA (p =.06) compared to the© education-only group. The effect of condition on the putative mediators did not explain these changes (all 95% CIs crossed 0), and family PA was associated with child MVPA only at 13 weeks (p <.01). Intervention 20 assignment had a small indirect effect on family PA (favouring©the education+planning group) via Habit. Perceived behavioural©control and habit were consistent predictors of family PA (p <.05), but not PA intention or planning intention (p >.05). The planning+education intervention showed improved family PA and planning intention, yet null mediation results suggest that other variables from the family system (e.g., child motivation, other parent's motivation and plans) are likely needed to fully understand the intervention effects. The promotion of perceived behavioural control and habit to assist in family PA is recommended for future research in this population.

Effects of the Preschool-Based Family-Involving DAGIS Intervention on Family Environment: A Cluster Randomised Trial

Interventions promoting young children’s healthy energy balance-related behaviours (EBRBs) should also examine changes in the family environment as this is an important determinant that may affect the effectiveness of the intervention. This study examines family environmental effects of the Increased Health and Wellbeing in Preschools (DAGIS) intervention study, and whether these effects differed when considering three parental educational level (PEL) groups. The DAGIS intervention was conducted in preschools and involving parents in Southern Finland from September 2017 to May 2018. It was designed as a randomised trial, clustered at preschool-level. Parents of 3–6-year-olds answered questionnaires recording PEL, parental role modelling for EBRBs, and the family environment measured as EBRBs availability and accessibility. Linear Mixed Models with Repeated Measures were used in order to detect intervention effects. Models included group by time interactions. When examining intervention effects separated by PEL groups, models with three-level interactions (group × time-points × PEL) were evaluated. There was an interaction effect for the availability of sugary everyday foods and drinks (p = 0.002). The analyses showed that the control group increased availability (p = 0.003), whereas in the intervention group no changes were detected (p = 0.150). In the analysis separated by PEL groups, changes were found only for the accessibility of sugary treats at home; the high PEL control group increased the accessibility of sugary treats (p = 0.022) (interaction effect: p = 0.027). Hence, results suggest that the DAGIS multicomponent intervention had a limited impact on determinants for children’s healthy EBRBs, and no impact was found in the low PEL group.

Getting Active with Active Video Games: A Quasi-Experimental Study

Given the cultural emphasis on academic achievement and environmental constraints to physical activity (PA), active video games (AVGs) may be used to decrease sedentary behavior and increase PA of Hong Kong children. This study explored the potential of a school-based AVG intervention on sedentary time, PA, body composition, and psychosocial factors among children. Eighty-seven children (intervention n = 30) were recruited from one primary school. Classes in Grades 4–6 were allocated to either the intervention group or the control group in a 2:1 ratio. The eight-week intervention involved children playing AVGs in an after-school class twice a week. Participants in the control group continued with their usual activities. Outcome included the change of participants in sedentary time, PA, percentage body fat, body mass index (BMI), and psychosocial variables (enjoyment, self-efficacy and social support), from baseline to eight weeks. No significant group differences were observed in sedentary time (−33.9 min/day, 95% CI −70.8 to 4.8; p = 0.07). The intervention group significantly increased total PA (53.7 counts/min, 95% CI 8.6 to 104.2; p = 0.04) compared with those in the control condition. No differences were found in body composition and psychosocial variables. However, significant treatment effects were found on BMI z score among boys (−0.1, 95% CI −0.2 to 0; p = 0.04). An eight-week school-based AVG intervention delivered during after-school hours was effective in increasing activity levels among Hong Kong children. The treatment effects of AVGs on sedentary behavior and body composition need to be further demonstrated in a more robust study, especially in boys.

Parents and children active together: a randomized trial protocol examining motivational, regulatory, and habitual intervention approaches

Background

Regular physical activity (PA) is associated with many health benefits during childhood, and tracks into desirable PA patterns and health profiles in adulthood. Interventions designed to support these behaviours among young children are critical. Family-based interventions focusing on parent-child activities together (i.e., co-activity) among preschool-aged children are warranted. Targeting parental support practices can increase the frequency of co-activity, however interventions must move beyond merely building intention and planning skills for successful maintenance. Interventions designed to increase co-activity habit strength may facilitate the sustainability and thus impact child PA. The purpose of this study is to compare the effects of three intervention conditions designed to increase child PA through co-activity: a standard education condition (information about benefits), a planning (action planning, coping planning) + education condition and a habit (context-dependent repetition from prompts and cues) + planning +education condition.

Methods/design

A longitudinal three-arm parallel design randomized trial will compare three conditions over six months. Families are eligible if they have at least one child between 3y and 5y that is not meeting 60mins/day of moderate to vigorous physical activity (MVPA). The primary outcome (child MVPA) is assessed via accelerometry at baseline, six weeks, three months and six months (primary endpoint). Intervention materials targeting co-activity are delivered post baseline assessment, with booster sessions at six weeks and three months. Parental co-activity habit, parent-child co-activity and other behavioural constructs are also assessed via questionnaire at all measurement occasions. As tertiary outcomes, parental PA is measured via accelerometry and co-activity is measured via a Bluetooth-enabled proximity feature. A total of 106 families have been recruited thus far from the Greater Victoria region. The study is ongoing with a minimum target of 150 families and an anticipated recruitment completion date of August 2022.

Discussion

This protocol describes the implementation of a randomized trial evaluating the effectiveness of a habit formation group compared with a planning group and an education only group to increase child PA through targeting parent-child co-activity. This information could prove useful in informing public health initiatives to promote PA among families with preschool-aged children.

Trial registration

This trial was prospectively registered on clinicaltrials.gov in February 2016, identifier NCT03055871.

Prevalence and Correlates of Physical Activity Among Children and Adolescents: A Cross-Sectional Population-Based Study of a Rural City in Japan

BACKGROUND

Although moderate-to-vigorous physical activity (MVPA) has multiple health benefits, current participation in recommended MVPA level and its determinants among Japanese children and adolescents remain unclear. Therefore, this cross-sectional study investigated the prevalence of meeting recommended MVPA level and its correlates among Japanese children and adolescents.

METHODS

Using the Japanese version of the World Health Organization (WHO) Health Behaviour in School-aged Children survey questionnaire, we confirmed the prevalence of meeting recommended MVPA level in all primary schools (PS) and junior high schools (JHS) in Unnan City, Japan. We evaluated its association with school grade, gender, body weight status, screen time, consumption of breakfast, physical activity (PA) preference, and population density using Poisson regression.

RESULTS

We found that 20.1% of the 1,794 students (9-15 years old) met the WHO recommendation. Meeting recommended MVPA level was significantly associated with being in the sixth grade of PS (prevalence ratio [PR] 0.57; 95% confidence interval [CI], 0.39-0.84) and first (PR 1.52; 95% CI, 1.16-1.99), second (PR 1.45; 95% CI, 1.10-1.90), and third grade of JHS (PR 0.40; 95% CI, 0.26-0.62) (vs fourth grade of PS); being a boy (PR 1.33; 95% CI, 1.12-1.59) (vs girl); liking PA (PR 3.72; 95% CI, 2.22-6.22) (vs dislike); and belonging to a medium-population-density (PR 0.73; 95% CI, 0.61-0.88) or low-population-density area (PR 0.67; 95% CI, 0.48-0.94) (vs high-population-density area).

CONCLUSIONS

About 20% of Japanese children and adolescents engaged in the recommended MVPA level. MVPA was associated with grade, gender, preference for PA, and population density.

Family-based habit intervention to promote parent support for child physical activity in Canada: protocol for a randomised trial

INTRODUCTION

Regular physical activity (PA) participation has many important physical and psychological health benefits, managing and preventing over 25 chronic conditions. Being more physically active as a child is associated with being more active as an adult, but less than 10% of Canadian children are achieving the recommended PA guidelines of 60 minutes per day of moderate to vigorous PA. Parental support is a predictor of child PA, but parent intention to support child PA does not always predict enacted support. Targeting factors that assist in the sustainability of parent support behaviour of child PA may have an impact on child PA. The purpose of this study is to evaluate an intervention designed to promote habit formation of parental support (HABIT, independent variable) on child PA (dependant variable) compared with a planning and education group (PLANNING) and an education only group (EDUCATION).

METHODS AND ANALYSIS

The three conditions will be compared using a 6-month longitudinal randomised trial. Eligible families have at least one child aged 6-12 years who is not meeting the 2011 Canadian PA Guidelines. Intervention materials are delivered at baseline, with check-in sessions at 6 weeks and 3 months. Child's moderate-to-vigorous PA, measured by accelerometry, is assessed at baseline, 6 weeks, 3 months and 6 months as the primary outcome. At baseline and 6 months, children perform fitness testing. Parents and children complete questionnaires at all timepoints. So far, 123 families have been recruited from the Greater Victoria and surrounding area. Recruitment will be continuing through 2020 with a target of 240 families.

ETHICS AND DISSEMINATION

This protocol has been approved by the University of Victoria Human Research Ethics Board (Victoria, Canada). Results will be shared at conferences as presentations and as published manuscripts. Study findings will be made available to interested participants.

TRIAL REGISTRATION NUMBER

NCT03145688; Pre-results.

Mediators of Behavior Change Maintenance in Physical Activity Interventions for Young and Middle-Aged Adults: A Systematic Review

Background

Regular physical activity is important for maintaining physical and mental health. Benefits are optimized when physical activity is maintained. Understanding causal mechanisms is important to inform future interventions.

Purpose

To investigate mediators of physical activity maintenance.

Methods

Six databases were searched (Medline, EMBASE, PsycINFO, CINAHL, Cochrane Database of Systematic Reviews, and Web of Science). Eligibility criteria included adult nonclinical populations, validated measure of physical activity behavior at baseline and at least 6 months postbaseline, control/comparison group(s), and reported mediators of physical activity behavior change. Mediators were examined according to (i) formal mediation tests, (ii) mediator association with physical activity outcome, and (iii) intervention effects on mediators.

Results

There were few formal mediation tests conducted (n = 12/39 included studies), and various other methodological limitations were identified. There was some evidence that effective mediators in formal mediation tests at 6 months and later included the "behavioral processes of change" (n = 5/6). Many of the included interventions were not effective for changing targeted mediators (only 34% of 413 tests of mediator changes were significant).

Conclusions

There were a number of methodological and statistical limitations in the evidence base. In future, prespecified formal mediation tests should be carried out and could be aided by a formal framework. Social and environmental variables should be considered in addition to intrapersonal variables. Improving knowledge of how to change hypothesized mediators, based on theory and evidence, will reveal how physical activity behavior change maintenance can be achieved. Maintenance research would be enhanced by establishing a formal definition of behavior change "maintenance." PROSPERO registration: PROSPERO 2015:CRD- 42015025462.

[Assistance programs for physical activity in Brazilian schools: a review based on the RE-AIM model]

The analysis of physical activity (PA) assistance programs is of major importance to ensure progress in the area. The Reach, Efficacy, Adoption, Implementation and Maintenance (RE-AIM) tool has been broadly disseminated in the literature. This study set out to identify PA assistance programs among Brazilian students and analyze them using the RE-AIM tool. The search was conducted in the Lilacs, SportDiscus, SciELO, Scopus, Web of Science, EBSCOhot, PsycINFO and PubMed databases. After thoroughly researching titles, abstracts and studies, 15 articles (seven PA assistance programs) were included. The programs were conducted in the past decade at public schools in the South and Southeast of Brazil. Multicomponent (education and teacher training) strategies were used with positive results in the practice of PA. With respect to the results of the RE-AIM tool, it was found that the most reported dimensions were "reach" (74%), followed by "efficacy" (48%), "adoption" (43%), "implementation" (35%) and "maintenance" (5%). The indicators most frequently mentioned were those related to the internal validity of the program: demographic and behavioral information of the target population, method of identification of the target population, sample size, participation rate and number of organizational units involved.

Freude am Sportunterricht − Welche Rolle spielen sportartspezifische Selbstkonzepte und die wahrgenommene Lehrerfürsorglichkeit von Schülerinnen und Schülern?

Zusammenfassung. Ziel der vorliegenden Studie war es, bei 239 Schülerinnen und Schülern (Mädchen: 45.2%) der 3.–5. Jahrgangsstufe fünf sportartspezifische Selbstkonzepte (Fußball, Basketball, Turnen, Leichtathletik, Schwimmen) faktorenanalytisch zu konzeptualisieren und die Zusammenhänge zwischen der Freude am Sportunterricht, diesen fünf sportartspezifischen Selbstkonzepten und der wahrgenommenen Lehrerfürsorglichkeit zu erfassen. Sowohl exploratorische als auch konfirmatorische Faktorenanalysen zeigten, dass die fünf sportartspezifischen Selbstkonzepte eindeutig voneinander trennbar sind. Die Freude am Sportunterricht korrelierte mit nahezu allen Selbstkonzeptfacetten und der wahrgenommenen Lehrerfürsorglichkeit positiv. Ein mehrebenenanalytisches Regressionsmodell legte nahe, dass sich bei Kontrolle des Geschlechts und Alters die Selbstkonzepte im Fußball und im Schwimmen sowie die wahrgenommene Lehrerfürsorglichkeit positiv auf die Freude am Sportunterricht auswirken. Grundschulkinder berichteten mehr Freude am Sportunterricht als Schülerinnen und Schüler in der Sekundarstufe, die dagegen eine höhere Lehrerfürsorglichkeit wahrnahmen als Grundschulkinder. Jungen berichteten höhere Selbstkonzepte im Fußball und im Basketball als Mädchen, während Mädchen höhere Selbstkonzepte im Turnen artikulierten als Jungen.

Goal feedback from whom? A physical activity intervention using an N-of-1 RCT

OBJECTIVE

Adolescents are not meeting the recommended guidelines for physical activity. Social support and self-regulatory skills are two factors known to impact physical activity and sedentary behaviour. The study sought to examine how targeting feedback as part of a self-regulatory process could increase physical activity, and the individual who should be providing the feedback.

DESIGN

The study utilised an aggregated N-of-1 RCT which allows for an iterative process of intervention development, and examines variability within participants to answer the question for whom did the intervention work. Ten adolescents (ages 13-18) set a daily physical activity goal. Adolescents received a SMS text message providing feedback on goal attainment daily from a parent, peer, behavioural health specialist; or no text message (control).

MAIN OUTCOME MEASURES

A bioharness heart rate monitor assessed heart rate as proxy for goal attainment. Adolescents also self-monitored their physical activity in the Calorie Counter and Diet Tracker by MyFitnessPal^TM app (commercially available).

RESULTS

Intervention demonstrated a significant effect for 30% of the sample in increasing MVPA (M_increase = 52 min), with no significant effect on sedentary behaviour.

CONCLUSION

A single occasion of text messaging from the right person can produce changes, however, careful consideration should be given to who provides the feedback.

"For whom was it effective?" Moderators of the effect of a school-based intervention on potential physical activity determinants among Brazilian students

Knowledge about the effects of school-based interventions on modifiable physical activity (PA) determinants (e.g., social support), and whether the intervention effect differs according to students' characteristics (e.g., age and gender) are relevant PA promotion topics. This study aims to answer these topics among Brazilian students. This cluster-randomized controlled trial was conducted with 548 students in the intervention group and 537 in the control group (51.5% of boys; aged 11-18years). The four-month intervention included strategies focused on training teachers, opportunities for PA in the school environment, and health education. Potential PA determinants (attitude, self-efficacy, support of friends, parents, and teachers, perceived neighborhood environment and PA facilities in school) and moderators (gender, age, socioeconomic status (SES), and PA level at baseline) were assessed using self-reported instrument. Height and weight were measured to estimate the students' body mass index (BMI) status. Generalized linear models were used. In general, there was a significant and positive intervention effect for attitude, support of friends and teachers for PA, as well as PA facilities in school; effect size was 0.29, 0.24, 0.34, and 0.29, respectively (P<0.05). Age (support of friends, parents and teachers, and PA facilities in school), SES (support of friends and PA facilities in school), and BMI status (support of friends) were moderators of the intervention effect on some outcomes. In conclusion, the intervention improved potential PA determinants, but some changes occurred differently according to students' characteristics. These findings should be considered in PA policies in the school context.

TRIAL REGISTRATION

This study is registered at Clinicaltrials.govNCT02439827.

An intervention to promote physical activity in Mexican elementary school students: building public policy to prevent noncommunicable diseases

Physical activity is an important component of strategies for health promotion and prevention of noncommunicable diseases. It is also associated with decreased risk for cardiovascular disease in overweight and obese adults and children. This article addresses the initial description of a physical activity intervention for children attending public elementary schools in Mexico. The objective was to develop a replicable model based on a strategic public, private, academic, and social partnership that would have a short-term impact on the metabolic health of children and be useful for building effective public policy. Forty-nine schools (20 000 students) participated, and 5 schools were selected for evaluation. The intervention included a 30-minute supervised middle-effort interchangeable routine, 5 days a week for a complete school year, adapted for different school conditions and students of different ages. Evaluation included anthropometric measurements and biochemical markers. Actual prevalence of combined overweight and obesity in these children was 31.9%. The intervention was successfully implemented in all schools. No change in body mass index, waist circumference, or other anthropometric indicators was found. However, changes in biochemical markers showed a significant decrease in blood glucose, total cholesterol, and cholesterol-low-density lipoproteins, reflecting a positive effect on cardiovascular health indicators.

A cluster-randomised controlled trial to promote physical activity in adolescents: the Raising Awareness of Physical Activity (RAW-PA) Study

Background

Recent technological advances provide an alternative yet underutilised opportunity for promoting physical activity in youth. The primary aim of the Raising Awareness of Physical Activity (RAW-PA) Study is to examine the short- and longer-term impact of a wearable activity monitor combined with digital behaviour change resources on adolescents’ daily physical activity levels.

Methods/Design

RAW-PA is a 12 week, multicomponent physical activity intervention that utilises a popular activity tracker (Fitbit® Flex) and supporting digital materials that will be delivered online via social media. The resources target key behaviour change techniques. The intervention structure and components have been informed by participatory research principles. RAW-PA will be evaluated using a cluster randomised controlled trial design with schools as the unit of randomisation. Twelve schools located in Melbourne, Australia, will allocated to either the intervention or wait-list control group. The target sample size is 300 Year 8 adolescents (aged 13–14 years). Participants’ moderate- to vigorous-intensity physical activity will be the primary outcome. Survey measures will be completed. Process factors (e.g. feasibility, acceptability/appeal, fidelity) will also be collected.

Discussion

To our knowledge, this study will provide some of the first evidence concerning the effect of wearable activity trackers and digital behaviour change resources on adolescents’ physical activity levels. This study will provide insights into the use of such technologies for physical activity promotion, which may have a significant impact on health education, promotion, practice and policy.

Trial registration

Australian and New Zealand Clinical Trials Registry No: ACTRN12616000899448. Date of registration: July 7, 2016.

Health game interventions to enhance physical activity self-efficacy of children: a quantitative systematic review

AIM

To describe and explore health game interventions that enhance the physical activity self-efficacy of children and to evaluate the effectiveness of these interventions.

BACKGROUND

Physical inactivity among children has increased globally. Self-efficacy is one of the key determinants of physical activity engagement in children. There is a need to explore new and innovative interventions to enhance physical activity self-efficacy that are also acceptable for today's children.

DESIGN

Quantitative systematic review.

DATA SOURCES

MEDLINE (Ovid), CINAHL, PsychInfo, EMBASE and the Cochrane Library between 1996-2016.

REVIEW METHODS

A review was conducted in accordance with the Cochrane Collaboration guidelines. A systematic search was done in June 2016 by two independent reviewers according to the eligibility criteria as follows: controlled trial, comparison of digital game intervention with no game intervention control condition, participants younger than 18 years of age and reported statistical analyses of a physical activity self-efficacy outcome measure.

RESULTS

Altogether, five studies met the eligibility criteria. Four game interventions, employing three active games and one educational game, had positive effects on children's physical activity self-efficacy. An intervention, employing a game-themed mobile application, showed no intervention effects. The variation between intervention characteristics was significant and the quality of the studies was found to be at a medium level.

CONCLUSION

Although health game interventions seemingly enhance the physical activity self-efficacy of children and have potential as a means of increasing physical activity, more rigorous research is needed to clarify how effective such interventions are in the longer run to contribute to the development of game-based interventions.

Testing the psychometric properties of Kidscreen-27 with Irish children of low socio-economic status

Background

Kidscreen-27 was developed as part of a cross-cultural European Union-funded project to standardise the measurement of children’s health-related quality of life. Yet, research has reported mixed evidence for the hypothesised 5-factor model, and no confirmatory factor analysis (CFA) has been conducted on the instrument with children of low socio-economic status (SES) across Ireland (Northern and Republic).

Method

The data for this study were collected as part of a clustered randomised controlled trial. A total of 663 (347 male, 315 female) 8–9-year-old children (M = 8.74, SD = .50) of low SES took part. A 5- and modified 7-factor CFA models were specified using the maximum likelihood estimation. A nested Chi-square difference test was conducted to compare the fit of the models. Internal consistency and floor and ceiling effects were also examined.

Results

CFA found that the hypothesised 5-factor model was an unacceptable fit. However, the modified 7-factor model was supported. A nested Chi-square difference test confirmed that the fit of the 7-factor model was significantly better than that of the 5-factor model. Internal consistency was unacceptable for just one scale. Ceiling effects were present in all but one of the factors.

Conclusions

Future research should apply the 7-factor model with children of low socio-economic status. Such efforts would help monitor the health status of the population.

Increasing Children's Voluntary Physical Activity Outside of School Hours Through Targeting Social Cognitive Theory Variables

INTRODUCTION

Volume of moderate-to-vigorous physical activity completed during the elementary school day is insufficient, and associated with health risks. Improvements in theory-based psychosocial factors might facilitate increased out-of-school physical activity.

METHODS

A behaviorally based after-school care protocol, Youth Fit 4 Life, was tested for its association with increased voluntary, out-of-school physical activity and improvements in its theory-based psychosocial predictors in 9- to 12-year-olds.

RESULTS

Increases over 12 weeks in out-of-school physical activity, and improvements in self-regulation for physical activity, exercise self-efficacy, and mood, were significantly greater in the Youth Fit 4 Life group (n = 88) when contrasted with a typical care control group (n = 57). Changes in the 3 psychosocial variables significantly mediated the group-physical activity change relationship (R(2) = .31, P < .001). Change in self-regulation was a significant independent mediator, and had a reciprocal relationship with change in out-of-school physical activity. In the Youth Fit 4 Life group, occurrence of 300 min/wk of overall physical activity increased from 41% to 71%.

CONCLUSIONS

Targeting theory-based psychosocial changes within a structured after-school care physical activity program was associated with increases in children's overall time being physically active. After replication, large scale application will be warranted.

Evaluation of physical activity interventions in children via the reach, efficacy/effectiveness, adoption, implementation, and maintenance (RE-AIM) framework: A systematic review of randomized and non-randomized trials

CONTEXT

Existing reviews of physical activity (PA) interventions designed to increase PA behavior exclusively in children (ages 5 to 11years) focus primarily on the efficacy (e.g., internal validity) of the interventions without addressing the applicability of the results in terms of generalizability and translatability (e.g., external validity).

OBJECTIVE

This review used the RE-AIM (Reach, Efficacy/Effectiveness, Adoption, Implementation, Maintenance) framework to measure the degree to which randomized and non-randomized PA interventions in children report on internal and external validity factors.

METHODS AND RESULTS

A systematic search for controlled interventions conducted within the past 12years identified 78 studies that met the inclusion criteria. Based on the RE-AIM criteria, most of the studies focused on elements of internal validity (e.g., sample size, intervention location and efficacy/effectiveness) with minimal reporting of external validity indicators (e.g., representativeness of participants, start-up costs, protocol fidelity and sustainability).

CONCLUSIONS

Results of this RE-AIM review emphasize the need for future PA interventions in children to report on real-world challenges and limitations, and to highlight considerations for translating evidence-based results into health promotion practice.

Reducing electronic media use in 2-3 year-old children: feasibility and efficacy of the Family@play pilot randomised controlled trial

Background

Participation in electronic media use among 2–3 year olds is high and associated with adverse health and developmental outcomes. This study sought to test the feasibility and potential efficacy of a family-based program to decrease electronic media (EM) use in 2–3-year-old children.

Methods

Family@play was a six-session pilot randomised controlled trial delivered to parents of 2–3 year-old children from August to September 2012 in a community environment in the Illawarra region of New South Wales, Australia. Development of program content was guided by Social Cognitive and Family Systems Theories. The primary outcome was children’s electronic media use. Secondary outcomes included children’s time in sitting, standing and stepping. Data collectors were blinded to group allocation. Parents completed comprehensive process evaluation measures and participated in focus group discussions following completion of the program. Regression analyses were undertaken and effect sizes calculated using principles of intention to treat.

Results

Twenty-two participants (n = 12 intervention; n = 10 control) provided complete baseline data; complete data from 16 participants (n = 6 intervention; n = 10 control) were available post-intervention. Process evaluation results were high, showing the acceptability of the program. Compared with children in the control group, there were greater decreases in total EM use among children in the intervention group (adjusted difference [95 % CI] = −31.2 mins/day [−71.0–8.6] Cohen’s d = 0.70). Differences for other outcomes were in the hypothesised direction and ranged from small for postural (sitting, standing, stepping) outcomes to moderate to large for individual electronic media (e.g. TV viewing, DVD/video viewing).

Conclusions

This is the first family-based study to engage families of 2–3 year old children outside the United States and target multiple EM behaviours. Family@play was shown to be a feasible and acceptable intervention to deliver to families of 2–3 year old children. Potential efficacy is evident from moderate to large effect sizes. A larger trial is warranted to test the efficacy of the program.

Trial registration

Australian New Zealand Clinical Trials Registry (ACTRN12612000470897).

Time with friends and physical activity as mechanisms linking obesity and television viewing among youth

Background

Though bivariate relationships between childhood obesity, physical activity, friendships and television viewing are well documented, empirical assessment of the extent to which links between obesity and television may be mediated by these factors is scarce. This study examines the possibility that time with friends and physical activity are potential mechanisms linking overweight/obesity to television viewing in youth.

Methods

Data were drawn from children ages 10-18 years old (M = 13.81, SD = 2.55) participating in the 2002 wave of Child Development Supplement (CDS) to the Panel Study of Income Dynamics (PSID) (n = 1,545). Data were collected both directly and via self-report from children and their parents. Path analysis was employed to examine a model whereby the relationships between youth overweight/obesity and television viewing were mediated by time spent with friends and moderate-to-vigorous physical activity (MVPA).

Results

Overweight/obesity was directly related to less time spent with friends, but not to MVPA. Time spent with friends was directly and positively related to MVPA, and directly and negatively related to time spent watching television without friends. In turn, MVPA was directly and negatively related to watching television without friends. There were significant indirect effects of both overweight/obesity and time with friends on television viewing through MVPA, and of overweight/obesity on MVPA through time with friends. Net of any indirect effects, the direct effect of overweight/obesity on television viewing remained. The final model fit the data extremely well (χ² = 5.77, df = 5, p<0.0001, RMSEA = 0.01, CFI = 0.99, TLI =0.99).

Conclusions

We found good evidence that the positive relationships between time with friends and physical activity are important mediators of links between overweight/obesity and television viewing in youth. These findings highlight the importance of moving from examinations of bivariate relationships between weight status and television viewing to more nuanced explanatory models which attempt to identify and unpack the possible mechanisms linking them.

Assessment of active play, inactivity and perceived barriers in an inner city neighborhood

Avondale, a disadvantaged neighborhood in Cincinnati, lags behind on a number of indicators of child well-being. Childhood obesity has become increasingly prevalent, as one-third of Avondale's kindergarteners are obese or overweight. The study objective was to determine perceptions of the quantity of and obstacles to childhood physical activity in the Avondale community. Caregivers of children from two elementary schools were surveyed to assess their child's physical activity and barriers to being active. Three hundred and forty surveys were returned out of 1,047 for a response rate of 32%. On school days, 41% of caregivers reported that their children spent more than 2 h watching television, playing video games, or spending time on the computer. While over half of respondents reported that their children get more than 2 h of physical activity on school days, 14% of children were reported to be physically active less than 1 h per day. Caregivers identified violence, cost of extracurricular activities, and lack of organized activities as barriers to their child's physical activity. The overwhelming majority of caregivers expressed interest in a program to make local playgrounds safer. In conclusion, children in Avondale are not participating in enough physical activity and are exposed to more screen time than is recommended by the AAP. Safety concerns were identified as a critical barrier to address in future advocacy efforts in this community. This project represents an important step toward increasing the physical activity of children in Avondale and engaging the local community.

Effect of a school-based intervention on physical activity and quality of life through serial mediation of social support and exercise motivation: the PESSOA program

The aim of this study was to explore the effects of social support and behavioral regulation of exercise on physical activity (PA) and quality of life (QoL), in a Portuguese school-based intervention. We hypothesized that serial mediation effects would be present leading to greater levels of PA and QoL. The sample comprised 1042 students (549 boys), aged 10-16 years, BMI = 19.31 ± 3.51, allocated to two groups of schools: control (n = 207) and intervention (n = 835). This study will report the 24 months results of the program, which aimed to develop healthy lifestyles. Questionnaires were used to measure PA, QoL, motivation to exercise and social support. There was no direct impact of the intervention on QoL or PA. Serial mediation analyses were conducted. Social support (P < 0.019) and intrinsic motivation (P = 0.085) increased more on intervention group. Indirect effects were observed in all serial mediation models. The positive indirect effects on PA and QoL were explained by the increase on peer/parent support in serial with the increase in intrinsic motivation (P < 0.01). Parental support led to an increase on external motivation (P < 0.05), which buffered the effects of the intervention. This school-based intervention promoted the development of social support and motivational mechanisms that explained higher levels of PA and QoL.

Physical activity and cardiovascular risk factors in children: meta-analysis of randomized clinical trials

OBJECTIVE

To assess the effects of physical activity interventions in preventing cardiovascular risk factors in childhood through a systematic review and meta-analysis of randomized clinical trials (RCTs).

METHODS

A search of online databases (PubMed, EMBASE and Cochrane CENTRAL) was conducted from inception until June 2013. RCTs enrolling children 6-12years old conducted physical activity interventions longer than 6months, assessing their effect on body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), total cholesterol (TC) and triglycerides (TG) were included. Data analysis was performed using a random-effects model.

RESULTS

Of 23.091 articles retrieved, 11 RCTs (10.748 subjects) were included. Physical activity interventions were not associated with reductions of BMI [-0.03kg/m(2) (95%CI -0.16, 0.13) I(2) 0%]. However, there was an association between the interventions and reduction of SBP [-1.25mmHg (95%CI -2.47, -0.02) I(2) 0%], DBP [-1.34mmHg (95%CI -2.57, -0.11) I(2) 43%] and TG [-0.09mmol/L (95%CI -0.14, -0.04) I(2) 0%], and increase of TC [0.14mmol/L (95%CI 0.01, 0.27) I(2) 0%].

CONCLUSION

As physical activity intervention programs lasting longer than 6months are associated with reductions in blood pressure levels and triglycerides, they should be considered to be included in prevention programs for cardiovascular diseases in schoolchildren.

Physical and social home environment in relation to children's overall and home-based physical activity and sedentary time

BACKGROUND

Given the obesity epidemic, it is critical to understand factors associated with youth physical activity and sedentary behavior at home, where youth spend significant time. We examined relationships between these child behaviors and home environment factors.

METHODS

Data were obtained from 713 children aged 6 to 11 in Washington and California 2007-2009. Multivariate regression analyses controlling for socio-demographics examined associations between parent-reported home environment factors and child's accelerometer-measured moderate-to-vigorous physical activity (MVPA) and sedentary time, overall and at home, and parent-reported child screen time.

RESULTS

Children averaged 47.2% of time at home, which included 43.6% and 46.4% of overall MVPA and sedentary behavior, respectively. Parental support for physical activity and having a basketball hoop were positively associated with MVPA and negatively associated with sedentary behavior. Combined parental support and a basketball hoop was associated with even higher MVPA. Children with fewer bedroom media devices and more fixed play equipment had lower overall sedentary behavior and screen time than either factor alone. Findings were similar regardless of weight status.

CONCLUSIONS

Physical and social home environment variables, especially when combined, were related to more child MVPA and less sedentary behavior. Results support addressing multiple home environment factors in childhood obesity prevention.

Using Pedometers for Measuring and Increasing Physical Activity in Children and Adolescents

The science and practice of step counting in children (typically aged 6-11 years) and adolescents (typically aged 12-19 years) has evolved rapidly over a relatively brief period with the commercial availability of research-grade pedometers and accelerometers. Recent reviews have summarized considerations for assessing physical activity using pedometers in young people (both children and adolescents), but 3 areas have received little attention: pedometer monitoring protocols, minimal (as opposed to optimal) step counts necessary for maintaining basal levels of health, and appropriate pedometer-based interventions for young people. Therefore, the objective of this review was to evaluate the current evidence and identify future research directions in these areas. The challenges of objective monitoring of physical activity in children and adolescents reinforce the importance of using protocols that minimize participant burden and the potential for tampering/reactivity. Evidence for a sedentary lifestyle cut point is limited; researchers are therefore encouraged to investigate several cut points (ie, <5000, <6000, <7000 steps/d) in children and adolescents to identify the health consequences of very low levels of ambulatory activity. Personalized messages may be necessary for health behavior change in pedometer-based interventions, but there is a need for more high-quality studies to develop the existing evidence base.

What Matters When Children Play: Influence of Social Cognitive Theory and Perceived Environment on Levels of Physical Activity Among Elementary-Aged Youth

OBJECTIVES

Social Cognitive Theory (SCT) has often been used as a guide to predict and modify physical activity (PA) behavior. We assessed the ability of commonly investigated SCT variables and perceived school environment variables to predict PA among elementary students. We also examined differences in influences between Hispanic and non-Hispanic students.

DESIGN

This analysis used baseline data collected from eight schools who participated in a four-year study of a combined school-day curriculum and environmental intervention.

METHODS

Data were collected from 393 students. A 3-step linear regression was used to measure associations between PA level, SCT variables (self-efficacy, social support, enjoyment), and perceived environment variables (schoolyard structures, condition, equipment/supervision). Logistic regression assessed associations between variables and whether students met PA recommendations.

RESULTS

School and sex explained 6% of the moderate-to-vigorous PA models' variation. SCT variables explained an additional 15% of the models' variation, with much of the model's predictive ability coming from self-efficacy and social support. Sex was more strongly associated with PA level among Hispanic students, while self-efficacy was more strongly associated among non-Hispanic students. Perceived environment variables contributed little to the models.

CONCLUSIONS

Our findings add to the literature on the influences of PA among elementary-aged students. The differences seen in the influence of sex and self-efficacy among non-Hispanic and Hispanic students suggests these are areas where PA interventions could be tailored to improve efficacy. Additional research is needed to understand if different measures of perceived environment or perceptions at different ages may better predict PA.

Accelerometer use during field-based physical activity research in children and adolescents with intellectual disabilities: a systematic review

Many methodological questions and issues surround the use of accelerometers as a measure of physical activity during field-based research. To ensure overall research quality and the accuracy of results, methodological decisions should be based on study research questions. This paper aims to systematically review accelerometer use during field-based research in children and adolescents with intellectual disabilities. Medline, Embase, Cochrane Library, Web of Knowledge, PsycINFO, PubMed, and a thesis database (up to May 2013) were searched to identify relevant articles. Articles which used accelerometry-based monitors, quantified activity levels, and included ambulatory children and adolescents (≤ 18 years) with intellectual disabilities were included. Based on best practice guidelines, a form was developed to extract data based on 17 research components of accelerometer use. The search identified 429 articles. Ten full-text articles met the criteria and were included in the review. Many shortcomings in accelerometer use were identified, with the percentage of review criteria met ranging from 12% to 47%. Various methods of accelerometer use were reported, with most use decisions not based on population-specific research. However, a lack of measurement research, e.g., calibration/validation, for children and adolescents with intellectual disabilities is limiting the ability of field-based researchers to make to the most appropriate accelerometer use decisions. The methods of accelerometer use employed can have significant effects on the quality and validity of results produced, which researchers should be more aware of. To allow informed use decisions, there should be a greater focus on measurement research related to children and adolescents with intellectual disabilities.

Dogs motivate obese children for physical activity: key elements of a motivational theory of animal-assisted interventions

Background: There is empirical evidence that the presence of a companion animal can have a positive impact on performance. The available evidence can be viewed in terms of differing hypotheses that attempt to explain the mechanisms behind the positive effects. Little attention has been given to motivation as a potential mode of action with regards to human-animal interactions. First we give an overview of evidence that animals might promote motivation. Second we present a study to examine the effect of a therapy dog on exercise performance in children with obesity.

Methods: Twelve children, aged 8–12 years old, were randomly assigned to two groups in a crossover design: dog-group and human confederate group. Several types of physical activities via accelerometer and subjective ratings of wellbeing, satisfaction, and motivation were assessed. Data were analyzed using analysis of variance for repeated measures on one factor.

Results: The main effect of condition was significant for all performance variables. There was less passive behavior and more physical activity for all performance variables in the presence of the dog than in that of the human confederate. Between dog- and human- condition there was no difference in the subjective rating of motivation, wellbeing, or satisfaction.

Discussion: The results demonstrate that the presence of a therapy dog has the potential to increase physical activity in obese children. Task performance as a declarative measure was increased by the presence of the dog in comparison to a human confederate, but self-report measures of motivation, satisfaction or wellbeing did not differ between the two conditions. Therefore, it stands to reason that a dog could trigger implicit motives which enhance motivation for activity. The results of our study indicate the potentially beneficial effect of incorporating dogs into outpatient training for obese children.