Professor David Lubans

© 2017 Informa UK Limited, trading as Taylor & Francis Group. High Intensity Interval Training (HIIT) may be effective for accumulating VPA. However, the contribution of HIIT to overall physical activity is unknown. Our primary aim was to explore the impact of school-based HIIT on physical activity. The secondary aim was to explore within-individual changes in physical activity after participating in HIIT. Participants [n = 65; 15.8(0.6)years] were randomized to a HIIT or control group. Intervention groups participated in three HIIT sessions/week. GENEActiv accelerometers assessed objective physical activity at baseline and week-one, to detect changes in MPA and VPA. Intervention effects were examined using linear mixed models and evidence of a change in physical activity (i.e., compensation) were examined using multilevel linear regression models. The group-by-time interaction effects for MPA and VPA were small and moderate, respectively. Adjusted difference between groups for VPA was 1.70 min/day, 95%CI ¿1.96 to 5.36; p = 0.354; d = 0.55). Embedding HIIT within the school-day had a moderate effect on VPA compared to controls. Compensation analyses (i.e., individual level) suggested that adolescents were more active on days when they participated in HIIT. Further studies are needed to test the effects of HIIT on adolescents¿ physical activity over extended time periods.

© 2017, © The Author(s) 2017. Objective: To explore young people¿s perceptions of pedometers and investigate behaviours exhibited while being monitored. Design: Qualitative design using six focus groups with participants (mean age 14.7 years). Setting: Study participants (n = 24) were randomly selected from a previous study of 123 young people aged 14¿15 years from three secondary schools in New South Wales (NSW), Australia. Methods: Participants wore pedometers (Yamax CW700) and accelerometers (ActiGraph GT3X+) simultaneously for 7 days. Accelerometer output was used to categorise participants into one of six focus groups (three boys groups and three girls groups): (1) low active (<30 minutes moderate to vigorous physical activity [MVPA]/day), (2) medium active (30¿60 minutes MVPA/day), and (3) high active (=60 minutes MVPA/day). Participants were questioned on their perceptions of the monitoring process and the behaviours that they exhibited while wearing pedometers. A hybrid approach to data analysis identified key concepts, which were thematically analysed. Results: The two main themes identified were (1) participants¿ perceptions of the monitoring process and (2) behaviour exhibited while being monitored. Overall, participants¿ attitudes towards objective monitoring were positive. A large proportion reported changing their levels of physical activity during the monitoring process, and 87.5% of focus group participants reported shaking their pedometers to increase their step counts. The medium and high active groups reported changing their activity patterns more than the low active groups. Conclusion: Our findings are consistent with previous quantitative studies that suggest reactivity and tampering are commonplace among young people. Pedometers may have more utility as an intervention strategy for increasing activity rather than as a method for assessing habitual activity levels.

© 2017 Informa UK Limited, trading as Taylor & Francis Group. Little is known about whether physical activity compensation occurs and, if so, what are potential moderators of such responses. This study examined whether children¿s physical activity, sedentary time and energy expenditure on one day was associated with these behaviours the following day, and what factors may moderate observed associations. One hundred and twenty-seven children (8¿11¿years) wore an ActiGraph accelerometer for eight days. Time spent in sedentary time and physical activity was obtained. Daily energy expenditure was also assessed using a SenseWear Armband (n=98). Moderators examined were sex, age, BMI, fitness, and fundamental movement skills (FMS). Multilevel analyses were conducted using generalized mixed models. On any given day, every additional 10¿minutes spent in moderate-to-vigorous physical activity (MVPA) was associated with 9.3¿minutes less MVPA the following day. Every additional 10kcal expended on one day was associated with 2.9 fewer kcal expended the following day. Additional time spent sedentary on any given day was associated with less light physical activity the following day in children with lower FMS. The results are largely consistent with the compensation hypothesis, with children appearing to compensate their activity between days. Strategies to minimise potential compensatory changes may be needed for children overall rather than for specific population sub-groups.

© 2017 by the American College of Sports Medicine. Purpose: Guidelines recommend that young people engage in muscle-strengthening activities on at least 3 dIwkj1. The purpose of this study was to examine the effect of a school-based intervention focused on resistance training (RT) for adolescents. Methods: The ''Resistance Training for Teens'' intervention was evaluated using a cluster-randomized, controlled trial with 607 adolescents (50.1% girls; 14.1 T 0.5 yr) from 16 secondary schools. Teachers were trained to deliver the intervention, which included the following: (i) an interactive student seminar; (ii) a structured physical activity program, focused on RT; (iii) lunchtime fitness sessions; and (iv) Web-based smartphone apps. The primary outcome was muscular fitness (MF) and secondary outcomes included body mass index, RT skill competency, flexibility, physical activity, self-efficacy, and motivation. Assessments were conducted at baseline, 6 months (postprogram; primary end point), and 12 months (follow-up). Outcomes were assessed using linear mixed models, with three potential moderators tested using interaction terms (and subgroup analyses where appropriate). Results: For the primary outcome (MF), a group-time effect was observed at 6 months for the upper body (2.0 repetitions; 95% confidence interval (CI), 0.8-3.2), but not the lower body (j1.4 cm; 95% CI, j4.7-1.9). At 6 months, there were intervention effects for RT skill competency and self-efficacy, but no other secondary outcomes. Effects for upper body MF and RT skill competency were sustained at 12 months. Despite overall no effect for body mass index, there was a group-time effect at 12 months among students whowere overweight/obese at baseline (j0.55 kgImj2; 95% CI, j1.01 toj0.08). Conclusions: The school-based RT intervention resulted in immediate and sustained improvements in upper body MF and RT skill competency, demonstrating an effective and scalable approach to delivering RT within secondary schools.

© 2018, Springer International Publishing AG, part of Springer Nature. Evidence supports a positive association between competence in fundamental movement skills (e.g., kicking, jumping) and physical activity in young people. Whilst important, fundamental movement skills do not reflect the broad diversity of skills utilized in physical activity pursuits across the lifespan. Debate surrounds the question of what are the most salient skills to be learned which facilitate physical activity participation across the lifespan. In this paper, it is proposed that the term ¿fundamental movement skills¿ be replaced with ¿foundational movement skills¿. The term ¿foundational movement skills¿ better reflects the broad range of movement forms that increase in complexity and specificity and can be applied in a variety of settings. Thus, ¿foundational movement skills¿ includes both traditionally conceptualized ¿fundamental¿ movement skills and other skills (e.g., bodyweight squat, cycling, swimming strokes) that support physical activity engagement across the lifespan. A proposed conceptual model outlines how foundational movement skill competency can provide a direct or indirect pathway, via specialized movement skills, to a lifetime of physical activity. Foundational movement skill development is hypothesized to vary according to culture and/or geographical location. Further, skill development may be hindered or enhanced by physical (i.e., fitness, weight status) and psychological (i.e., perceived competence, self-efficacy) attributes. This conceptual model may advance the application of motor development principles within the public health domain. Additionally, it promotes the continued development of human movement in the context of how it leads to skillful performance and how movement skill development supports and maintains a lifetime of physical activity engagement.

© 2018 Elsevier Ltd Objective: To examine the impact of a school-based physical activity intervention on adolescents' self-esteem and subjective well-being, and to explore moderators and mediators of intervention effects. Methods: Resistance Training for Teens was evaluated using a cluster RCT in 16 schools located in New South Wales, Australia. Adolescents (N = 508; 14.1 ± 0.5 years; 49.6% female) completed measures of global self-esteem, subjective well-being, and hypothesized mediators (i.e., perceived fitness, resistance training self-efficacy, and autonomous motivation) at baseline (April¿June, 2015) and post-intervention (October¿December). The school-based physical activity program was delivered by teachers over 10-weeks via Physical Education, co-curricular school sport, or an elective subject known as Physical Activity and Sport Studies, and involved once-weekly fitness sessions and additional lunch-time sessions. Intervention effects and moderator analyses were tested using multi-level linear regression analyses with interaction terms. Multi-level mediation analyses were used to explore potential mediators of changes in well-being outcomes. Results: Intervention effects for self-esteem (ß = 0.05, p =.194) and wellbeing (ß = 0.03, p =.509) were not statistically significant. Moderator analyses showed effects for self-esteem were greater for the overweight/obese subgroup (p =.069 for interaction), and resistance training self-efficacy was a significant mediator of changes in self-esteem (product-of-coefficients [AB] = 0.021, SE = 0.010, 95% CIs = 0.002 to 0.040). No other significant indirect effects were observed. Conclusion: Overall, Resistance Training for Teens did not improve adolescents' self-esteem or subjective well-being. However, our mediation findings lend support to resistance training self-efficacy as a mechanism explaining the positive effect of resistance training on self-esteem.

© 2018 Human Kinetics, Inc. This study aimed to examine the contribution of objective measures of physical fitness (musculoskeletal and cardiorespiratory), physical activity, and motor skill to motor perception. A total of 122 children (63 boys) aged 8-11 years were assessed. Independent t-tests assessed sex differences in all variables. Two linear mixed models adjusted for sex and age were performed with perceived object control and locomotor skills (Pictorial Scale of the Perceived Movement Skill Competence for Young Children) as outcomes. Aerobic (multi-stage fitness test) and muscular fitness (long jump, grip strength), moderate-to-vigorous physical activity (ActiGraph accelerometry), movement skill (Test of Gross Motor Development-2), age, and sex were predictors. Boys had higher object control skills (actual and perceived) and fitness. Age (decreasing) and long jump distance (positive) explained 16% of locomotor skill perception variance. Sex (boys) explained 13% of object control skill perception variance. Children's skill selfperception may be influenced by fitness attributes as these are more evident to them. The fact that girls have lower actual object control competence and fitness than boys suggests girls may be an intervention target.

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. Numerous skill batteries assess fundamental motor skill (e.g., kick, hop) competence. Few skill batteries examine lifelong physical activity skill competence (e.g., resistance training). This study aimed to develop and assess the content validity, test-retest and inter-rater reliability of the ¿Lifelong Physical Activity Skills Battery¿. Development of the skill battery occurred in three stages: i) systematic reviews of lifelong physical activity participation rates and existing motor skill assessment tools, ii) practitioner consultation and iii) research expert consultation. The final battery included eight skills: grapevine, golf swing, jog, push-up, squat, tennis forehand, upward dog and warrior I. Adolescents (28 boys, 29 girls; M¿=¿15.8¿years, SD¿=¿0.4¿years) completed the Lifelong Physical Activity Skills Battery on two occasions two weeks apart. The skill battery was highly reliable (ICC¿=¿0.84, 95% CI¿=¿0.72¿0.90) with individual skill reliability scores ranging from moderate (warrior I; ICC¿=¿0.56) to high (tennis forehand; ICC¿=¿0.82). Typical error (4.0; 95% CI 3.4¿5.0) and proportional bias (r¿=¿-0.21, p¿=¿.323) were low. This study has provided preliminary evidence for the content validity and reliability of the Lifelong Physical Activity Skills Battery in an adolescent population.

© 2017 Informa UK Limited, trading as Taylor & Francis Group. The aim of this study is to examine the prevalence and correlates of adolescents¿ resistance training (RT) skill competence. Participants were 548 adolescents (14.1¿±¿0.5¿years) from 16 schools in New South Wales, Australia. RT skills were assessed using the Resistance Training Skills Battery. Demographics, BMI, muscular fitness, perceived strength, RT self-efficacy, and motivation for RT were also assessed. The proportion demonstrating ¿competence¿ and ¿near competence¿ in each of the six RT skills were calculated and sex differences explored. Associations between the combined RT skill score and potential correlates were examined using multi-level linear mixed models. Overall, the prevalence of competence was low (range¿=¿3.3% to 27.9%). Females outperformed males on the squat, lunge and overhead press, whereas males performed better on the push-up (p¿<.05). Significant associations were seen for a number of correlates, which largely differed by sex. Muscular fitness was moderately and positively associated with RT skills among both males (ß¿=¿0.34, 95%CIs¿=¿0.23 to 0.46) and females (ß¿=¿0.36, 95%CIs¿=¿0.23 to 0.48). Our findings support a link between RT skills and muscular fitness. Other associations were statistically significant but small in magnitude, and should therefore be interpreted cautiously.

© 2018 Elsevier Ltd Objective The present study examined the effect of a school-based multicomponent physical activity intervention on aggression in adolescent males from low-income areas, and explored potential mediators of change in aggression. Methods Participants were adolescent males (N = 361; 12.7 ± 0.5 years) enrolled in the ¿Active Teen Leaders Avoiding Screen-time¿ cluster RCT. Self-report measures for aggression, perceived strength and recreational screen-time were collected at baseline and 8-months. The effect of the intervention on aggression was tested using multi-level linear regression and potential mediators (i.e., screen-time and perceived strength) were explored using a product-of-coefficients test. Results There was no significant intervention effects for aggression (C [SE] = -0.038 [0.044], p =.384) or perceived strength (A [SE] = -0.0 [0.0], p =.884). However, a statistically significant effect was found for screen-time (A [SE] = -0.160 [0.04], p= <0.01). Changes in screen-time significantly mediated changes in aggression at post-test (AB [SE] = -0.021 [0.009], 95% CI = -0.042 to -0.005). Conclusion Limiting recreational screen-time may help to reduce aggression in adolescent boys. Interventions targeting adolescents' recreational screen-time should examine their ¿flow-on¿ effects on externalising behaviours in adolescent populations.

© 2018 Human Kinetics, Inc. Participation in lifelong physical activities, such as yoga, golf, tennis, or running, are common endeavors in adolescence and adulthood. However, there is a lack of understanding of how competent individuals are in the skills needed for these activities and how competency in these skills relates to physical activity and fitness. This study aimed to determine the initial predictive validity of the Lifelong Physical Activity Skills Battery related to physical activity and health-related fitness. One-hundred and nine adolescents from four schools (55 males, 54 females; Mage = 15.82 years, SD = 0.37 years) completed: demographic information (survey), height (stadiometer), weight (digital scale), motor skill assessment (jog, grapevine, squat, push-up, upward dog, warrior one, tennis forehand, golf swing), health-related fitness (standing long jump, back-saver sit and reach, 3-min submaximal step test, 90° push-up test), and physical activity (GENEActiv accelerometers). Correlations and multiple regression models were conducted in SPSS version 24.0. Motor competence was associated with muscular fitness (standing long jump, ß = 0.24, p = .002; push-ups, ß = 0.42, p < .001), cardiorespiratory fitness (ß = 0.21, p = .031), and flexibility (ß = 0.23, p = .025), but not physical activity (ß = 0.17, p = .154) or body mass index (ß = -0.05, p = .622) Motor competence has a stronger association with health-relatedfitness parameters rather than physical activity.

© 2017 American Journal of Preventive Medicine Context The mental health benefits of physical activity are well established. However, less is known about whether the relationship between physical activity and mental health is consistent across different life domains. It is important to understand how context may influence the relationship between physical activity and mental health so that interventions and policy guidelines can be tailored to maximize positive effects. Evidence acquisition In 2015, systematic searches of four databases identified 13,435 records, of which 98 studies met the inclusion criteria. Evidence synthesis Included studies were published between 1988 and 2015 and had a combined sample size of 648,726. Of the 98 included studies, 93 examined leisure-time physical activity, 14 examined work-related physical activity, 15 examined transport physical activity, 16 examined household physical activity, three examined school sport, and three examined physical education. Multi-level meta-analyses showed that leisure-time physical activity (r =0.13) and transport physical activity (r =0.13) both had a positive association with mental health. Leisure-time physical activity (r = ¿0.11) and school sport (r = ¿0.09) both had an inverse association with mental ill-health. However, physical activity was not consistently associated with lower mental ill-health across domains, as work-related physical activity was positively associated with mental ill-health (r =0.09). Household physical activity and participation in physical education had no relationship with mental health or mental ill-health. Conclusions The domain in which physical activity occurs influences the relationship between physical activity and mental health and should, therefore, be considered when developing interventions, treatment programs, and policy guidelines.

© 2016, © The Author(s) 2016. The primary objective of this study was to evaluate the efficacy of a continuing professional development (CPD) intervention in producing changes in physical education (PE) teaching practice and PE teaching quality by generalist primary school teachers when the CPD addressed the use of a game-centred approach. A cluster randomized controlled trial was conducted in seven primary schools in the Hunter Region, New South Wales, Australia. One year six teacher from each school was randomized into the Professional Learning for Understanding Games Education (PLUNGE) intervention (n = 4 teachers) or the 7-week wait-list control (n = 3) condition. The PLUNGE intervention (weeks 1¿5) used an instructional framework to improve teachers¿ knowledge, understanding and delivery of a game-centred curriculum, and included an information session and weekly in-class mentoring. The intervention was designed to enhance content and pedagogical knowledge for the provision of pedagogy focused on a broad range of learning outcomes. Teaching quality was assessed at baseline and follow-up (weeks 6 and 7) via observation of two consecutive PE lessons using the Quality Teaching Lesson Observation Scales. Linear mixed models revealed significant group-by-time intervention effects (p < 0.05) for the quality of teaching (effect size: d = 1.7). CPD using an information session and mentoring, and a focus on the development of the quality of teaching using a game-centred pedagogical approach was efficacious in improving the quality of PE teaching among generalist primary school teachers.

© 2016 Elsevier Inc. This review aimed to determine the most popular physical activities performed by children, adolescents, and adults globally. Statistic bureau websites and article databases Scopus, ProQuest, SPORTDiscus, and Science Direct were searched between November 17th, 2014 and April 31st, 2015. Eligible studies were published in the last 10¿years with participation rates for specific physical activities among individuals five years or older. Data extraction for included articles (n¿=¿64) was assessed independently and agreed upon by two authors. A random-effects model was used to calculate participation rates in specific activities for each age group and region. In total 73,304 articles were retrieved and 64 articles representing 47 countries were included in the final meta-analysis. Among adults, walking was the most popular activity in the Americas (18.9%; 95% CI 10.2 to 32.5), Eastern Mediterranean (15.0%; 95% CI 5.8 to 33.6), Southeast Asia (39.3%; 95% CI 0.9 to 98.0) and Western Pacific (41.8%; 95% CI 25.2 to 60.6). In Europe and Africa, soccer (10.0%; 95% CI 6.5 to 15.1) and running (9.3%; 95% CI 0.9 to 53.9), respectively, were top activities. Child and adolescent participation results were highly dependent upon region. American youth team sport participation was high, while youth from the Eastern Mediterranean and Western Pacific were more likely to report participation in lifelong physical activities. Global data for adults reflects a consistent pattern of participation in running and walking. Among all age groups and regions soccer was popular. In children and adolescents, preferences were variable between regions.

© 2017 Elsevier Ltd Introduction The primary aim was to examine longitudinal associations between changes in screen-time and mental health outcomes among adolescents. Methods Adolescents (N¿=¿322, 65.5% females, mean age¿=¿14.4¿±¿0.6 years) reported screen-time and mental health at two time points over a school year. Multi-level linear regression analyses were conducted after adjusting for covariates. Results Changes in total recreational screen-time (ß¿=¿-0.09 p¿=¿0.048) and tablet/mobile phone use (ß¿=¿-0.18, p¿<¿0.001) were negatively associated with physical self-concept. Changes in total recreational screen-time (ß¿=¿-0.20, p¿=¿0.001) and computer use (ß¿=¿-0.23, p¿=¿0.003) were negatively associated with psychological well-being. A positive association was found with television/DVD use and psychological difficulties (ß¿=¿0.16, p¿=¿0.015). No associations were found for non-recreational screen-time. Conclusion Changes in recreational screen-time were associated with changes in a range of mental health outcomes.

© 2017 The Author(s). Background: The Self-determined Exercise and Learning For FITness (SELF-FIT) is a multi-component school-based intervention based on tenets of self-determination theory. SELF-FIT aims to increase students' moderate-to-vigorous physical activity (MVPA) during physical education lessons, and enhance their autonomous motivation towards fitness activities. Using a cluster randomized controlled trial, we aim to examine the effects of the intervention on students' MVPA during school physical education. Methods: Secondary 2 students (approximately aged 14 years) from 26 classes in 26 different schools will be recruited. After baseline assessments, students will be randomized into either the experimental group or wait-list control group using a matched-pair randomization. Teachers allocated to the experimental group will attend two half-day workshops and deliver the SELF-FIT intervention for 8 weeks. The main intervention components include training teachers to teach in more need supportive ways, and conducting fitness exercises using a fitness dice with interchangeable faces. Other motivational components, such as playing music during classes, are also included. The primary outcome of the trial is students' MVPA during PE lessons. Secondary outcomes include students' leisure-time MVPA, perceived need support from teachers, need satisfaction, autonomous motivation towards physical education, intention to engage in physical activity, psychological well-being, and health-related fitness (cardiorespiratory and muscular fitness). Quantitative data will be analyzed using multilevel modeling approaches. Focus group interviews will also be conducted to assess students' perceptions of the intervention. Discussion: The SELF-FIT intervention has been designed to improve students' health and well-being by using high-intensity activities in classes delivered by teachers who have been trained to be autonomy needs supportive. If successful, scalable interventions based on SELF-FIT could be applied in physical education at large. Trial registration: The trial is registered at the Australia New Zealand Clinical Trial Registry (Trial ID: ACTRN12615000633583; date of registration: 18 June 2015).

© 2017 Sports Medicine Australia Objective To determine the comparability and feasibility of wrist- and hip-worn accelerometers among free-living adolescents. Design 89 adolescents (age = 13¿14 years old) from eight secondary schools in New South Wales (NSW), Australia wore wrist-worn GENEActiv and hip-worn ActiGraph (GT3X+) accelerometers simultaneously for seven days and completed an accelerometry behavior questionnaire. Methods Bivariate correlations between the wrist- and hip-worn out-put were used to determine concurrent validity. Paired samples t-test were used to compare minutes per day in moderate-to-vigorous physical activity (MVPA). Group means and paired sample t-tests were used to analyze participants¿ perceptions of the wrist- and hip-worn monitoring protocols to assist with determining the feasibility. Results Wrist-worn accelerometry compared favorably with the hip-worn in average activity (r = 0.88, p < 0.001) and MVPA (r = 0.84 p < 0.001, mean difference = 3.54 min/day, SD = 12.37). The wrist-worn accelerometer had 50% fewer non-valid days (75 days, 12%) than the hip-worn accelerometer (n = 152, 24.4%). Participants reported they liked to wear the device on the wrist (p < 0.01), and that it was less uncomfortable (p = 0.02) and less embarrassing to wear on the wrist (p < 0.01). Furthermore, that they would be more willing to wear the device again on the wrist over the hip (p < 0.01). Conclusions Our findings reveal there is a strong linear relationship between wrist- and hip-worn accelerometer out-put among adolescents in free-living conditions. Adolescent compliance was significantly higher with wrist placement, with participants reporting that it was more comfortable and less embarrassing to wear on the wrist.

© 2017 Elsevier Inc. The risk and prevalence of Type 2 Diabetes (T2D) has dramatically increased over the past decade. The aim of this study was to develop, implement and evaluate a physical activity intervention to improve aerobic and muscular fitness among adults at risk of, or diagnosed with T2D. A 20-week, assessor blinded, parallel-group randomized controlled trial (RCT) was conducted at the University of Newcastle (June¿December 2015). Adults were randomized to the intervention (n = 42) or wait-list control group (n = 42). The theory-based intervention included: Phase 1 (weeks 1¿10) integrated group sessions (outdoor physical activity and cognitive mentoring), and the eCoFit smartphone application (app). Phase 2 (weeks 11¿20) only included the eCoFit app. Participants were assessed at baseline, 10 weeks and 20 weeks. Linear mixed models (intention-to-treat) were used to determine group-by-time interactions at 10 weeks (primary time-point) and 20 weeks for the primary outcomes. Several secondary outcomes were also assessed. After 10 weeks, significant group-by-time effects were observed for aerobic fitness (4.5 mL/kg/min; 95% CI [1.3, 7.7], d = 0.68) and muscular fitness (lower body) (3.4 reps, 95% CI [2.7, 4.2], d = 1.45). Intervention effects for secondary outcomes included significant increased physical activity (1330 steps/week), improved upper body muscular fitness (5 reps; arm-curl test), improved functionality (- 1.8 s; timed-up and go test) reduced waist circumference (2.8 cm) and systolic blood pressure (- 10.4 mm Hg). After 20 weeks, significant effects were observed for lower body muscular fitness and health outcomes. eCoFit is an innovative lifestyle intervention which integrates smartphone technology, social support, and the outdoor environment to improve aerobic and muscular fitness.

© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted. Objective Regular participation in resistance training (RT) is critical to health and recommended in most international physical activity guidelines. Few people, however, participate in RT. The purpose of this review was to assess the demographic, behavioural, intrapersonal, interpersonal and environmental factors associated with participating in RT. Data sources Eligible studies were from English peer-reviewed published articles that examined correlates or determinants of RT in adult samples. Searches were performed from August 2015 to April 2016 in six databases. Results We identified 51 independent data sets, from nine countries, primarily of moderate to high quality, and 23 factors related to participating in RT. Education, perceived health status, quality of life, affective judgements, self-efficacy, intention, self-regulation behaviours, subjective norm and programme leadership were associated with RT. Conclusion Low education levels and poor health status were associated with low participation rates in RT. Intrapersonal factors including affective judgements, self-efficacy, and self-regulation behaviours, and interpersonal factors including subjective norms and programme leadership may be important for promoting RT behaviours.

© 2016, Springer Science+Business Media New York. The mechanisms of behavior change in youth screen-time interventions are poorly understood. Participants were 361 adolescent boys (12¿14¿years) participating in the ATLAS obesity prevention trial, evaluated in 14 schools in low-income areas of New South Wales, Australia. Recreational screen-time was assessed at baseline, 8- and 18-months, whereas potential mediators (i.e., motivation to limit screen-time and parental rules) were assessed at baseline, 4- and 18-months. Multi-level mediation analyses followed the intention-to-treat principle and were conducted using a product-of-coefficients test. The intervention had a significant impact on screen-time at both time-points, and on autonomous motivation at 18-months. Changes in autonomous motivation partially mediated the effect on screen-time at 18-months in single and multi-mediator models [AB (95% CI)¿=¿-5.49 (-12.13, -.70)]. Enhancing autonomous motivation may be effective for limiting screen-time among adolescent males. Trial registration: Australian New Zealand Clinical Trials Registry No: ACTRN12612000978864.

© 2017 World Obesity Federation Objective: The aims of this systematic review and meta-analysis are (i) to determine the impact of school-based interventions on objectively measured physical activity among adolescents and (ii) to examine accelerometer methods and decision rule reporting in previous interventions. Methods: A systematic search was performed to identify randomized controlled trials targeting adolescents (age: =10¿years), conducted in the school setting, and reporting objectively measured physical activity. Random effects meta-analyses were conducted to determine the pooled effects of previous interventions on total and moderate-to-vigorous physical activity. Potential moderators of intervention effects were also explored. Results: Thirteen articles met the inclusion criteria, and twelve were included in the meta-analysis. The pooled effects were small and non-significant for both total physical activity (standardized mean difference¿=¿0.02 [95% confidence interval¿=¿-0.13 to 0.18]) and moderate-to-vigorous physical activity (standardized mean difference¿=¿0.24 [95% confidence interval¿=¿-0.08 to 0.56]). Sample age and accelerometer compliance were significant moderators for total physical activity, with a younger sample and higher compliance associated with larger effects. Conclusion: Previous school-based physical activity interventions targeting adolescents have been largely unsuccessful, particularly for older adolescents. There is a need for more high-quality research using objective monitoring in this population. Future interventions should comply with best-practice recommendations regarding physical activity monitoring protocols.

© 2017 The Author(s). Background: Schools play an important role in physical activity promotion for adolescents. The systematic review aimed to determine the proportion of secondary (middle and high) school physical education (PE) lesson time that students spend in moderate to vigorous physical activity (MVPA), and to assess if MVPA was moderated by school level (middle and high school), type of physical activity measurement and type of PE activities. Methods: A systematic search of nine electronic databases was conducted (PROSPERO2014:CRD42014009649). Studies were eligible if they were published between 2005 and 2014; written in English; assessed MVPA in PE lessons of secondary (middle and high) school students; and used a quantitative MVPA measure (i.e., accelerometry, heart rate monitoring, pedometers or observational measures). Two reviewers examined the retrieved articles, assessed risk of bias, and performed data extraction. Random effects meta-analysis was used to calculate a pooled estimate of the percent of PE lesson time spent in MVPA and to assess moderator effects where data allowed. Results: The search yielded 5,132 potentially relevant articles; 28 articles representing 25 studies (7 middle and 18 high school) from seven countries were included. Twelve studies measured MVPA through observational measures, seven used accelerometers, five used heart rate monitors and four used pedometers (including three studies using a mix of measures). Meta-analysis of 15 studies found that overall, students spent a mean (95% CI) of 40.5% (34.8-46.2%) of PE in MVPA. Middle school students spent 48.6% (41.3-55.9%) of the lesson in MVPA (n=5 studies) and high school students 35.9% (28.3-43.6%) (n=10 studies). Studies measuring MVPA using accelerometers (n=5) showed that students spent 34.7% (25.1-44.4%) of the lesson in MVPA, while 44.4% (38.3-50.5%) was found for lessons assessed via observation (n=9), 43.1% (24.3-61.9%) of the lesson for a heart rate based study, and 35.9% (31.0-40.8%) for a pedometer-measured study. Conclusions: The proportion of PE spent in MVPA (40.5%) is below the US Centre for Disease Control and Prevention and the UK Associations for Physical Education recommendation of 50%. Findings differed according to the method of MVPA assessment. Additional strategies and intervention research are needed to build more active lesson time in PE.

© 2015 Elsevier Inc. Objective: To examine elementary school students' moderate-to-vigorous physical activity (MVPA) levels during physical education (PE) lessons. Methods: A systematic search of nine electronic databases was conducted (PROSPERO2014:CRD42014009649). Studies were eligible if they were in English; published between 2005-April 2014; assessed MVPA levels in PE lessons of elementary school children (aged four-12 years); and used an objective MVPA measure. Two reviewers retrieved articles, assessed risk of bias, and performed data extraction. The findings were synthesised using a meta-analysis. Results: The search yielded 5132 articles. Thirteen studies from nine countries met the inclusion criteria. Eight studies measured MVPA through observational measures, five used accelerometry and one used heart rate monitoring. The percentage of PE lesson time spent in MVPA ranged between 11.4-88.5%. Meta-analysis of seven studies (direct observations; 4 accelerometers) found that children spent a mean (95% CI) 44.8 (28.2-61.4)% of PE lesson time in MVPA. When measured using direct observation and accelerometers, children spent 57.6 (47.3-68.2) and 32.6 (5.9-59.3)% of PE lesson time in MVPA, respectively. The review has limitations; the search strategy was restricted to studies in English; theses, dissertations and conference abstracts were excluded; and six studies that provided insufficient data were excluded from the meta-analysis. Conclusion: MVPA levels during elementary school PE lessons do not meet the United States Centre for Disease Control and Prevention and the United Kingdom's Association of Physical Education recommendation (50% of lesson time), but is higher than estimated in the previous review (34.2%). Interventions to increase MVPA in PE lessons are needed.

© 2016 Stacey et al. Background: Despite increasing numbers of cancer survivors and evidence that diet and physical activity improves the health of cancer survivors, most do not meet guidelines. Some social cognitive theory (SCT)-based interventions have increased physical activity behavior, however few have used objective physical activity measures. The Exercise and Nutrition Routine Improving Cancer Health (ENRICH) randomized controlled trial reported a significant intervention effect for the primary outcome of pedometer-assessed step counts at post-test (8-weeks) and follow-up (20-weeks). The aim of this study was to test whether the SCT constructs operationalized in the ENRICH intervention were mediators of physical activity behavior change. Methods: Randomized controlled trial with 174 cancer survivors and carers assessed at baseline, post-test (8-weeks), and follow-up (20-weeks). Participants were randomized to the ENRICH six session face-to-face healthy lifestyle program, or to a wait-list control. Hypothesized SCT mediators of physical activity behavior change (self-efficacy, behavioral goal, outcome expectations, impediments, and social expectations) were assessed using valid and reliable scales. Mediation was assessed using the Preacher and Hayes SPSS INDIRECT macro. Results: At eight weeks, there was a significant intervention effect on behavioral goal (A = 9.12, p = 0.031) and outcome expectations (A = 0.25, p = 0.042). At 20 weeks, the intervention had a significant effect on self-efficacy (A = 0.31, p = 0.049) and behavioral goal (A = 13.15, p = 0.011). Only changes in social support were significantly associated with changes in step counts at eight weeks (B = 633.81, p = 0.023). Behavioral goal was the only SCT construct that had a significant mediating effect on step counts, and explained 22 % of the intervention effect at 20 weeks (AB = 397.9, 95 % CI 81.5-1025.5). Conclusions: SCT constructs had limited impact on objectively-assessed step counts in a multiple health behavior change intervention for cancer survivors and their carers. Behavioral goal measured post-intervention was a significant mediator of pedometer-assessed step counts at 3-months after intervention completion, and explained 22 % of the intervention effect. Future research should examine the separate impact of goals and planning, as well as examining mediators of behavior maintenance in physical activity interventions targeting cancer survivors. Trial registration: Australian and New Zealand Clinical Trials registry ANZCTRN1260901086257.

© 2016 Human Kinetics, Inc. Background: Two years on from the inaugural Active Healthy Kids Australia (AHKA) Physical Activity Report Card, there has been little to no change with the majority of Australian children still insufficiently active. Methods: The 2016 AHKA Report Card was developed using the best available national-and state-based physical activity data, which were evaluated by the AHKA Research Working Group using predetermined weighting criteria and benchmarks to assign letter grades to the 12 Report Card indicators. Results: In comparison with 2014, Overall Physical Activity Levels was again assigned a D-with Organized Sport and Physical Activity Participation increasing to a B (was B-) and Active Transport declining to a C-(was C). The settings and sources of influence again performed well (A-to a C+), however Government Strategies and Investments saw a decline (C+ to a D). The traits associated with physical activity were also graded poorly (C-to a D). Conclusions: Australian youth are insufficiently active and engage in high levels of screen-based sedentary behaviors. While a range of support structures exist, Australia lacks an overarching National Physical Activity Plan that would unify the country and encourage the cultural shift needed to face the inactivity crisis head on.

© 2016 The Author(s). Background: Few school-based interventions have been successful in reducing physical activity decline and preventing overweight and obesity in adolescent populations. As a result, few cost effectiveness analyses have been reported. The aim of this paper is to report the cost and cost effectiveness of the Physical Activity 4 Everyone (PA4E1) intervention which was a multi-component intervention implemented in secondary schools located in low-income communities. Cost effectiveness was assessed using both the physical activity and weight status trial outcomes. Methods: Intervention and Study Design: The PA4E1 cluster randomised controlled trial was implemented in 10 Australian secondary schools (5 intervention: 5 control) and consisted of intervention schools receiving seven physical activity promotion strategies and six additional strategies that supported school implementation of the intervention components. Costs associated with physical activity strategies, and intervention implementation strategies within the five intervention schools were estimated and compared to the costs of usual physical activity practices of schools in the control group. The total cost of implementing the intervention was estimated from a societal perspective, based on the number of enrolled students in the target grade at the start of the intervention (Grade 7, n = 837). Economic Outcomes: The economic analysis outcomes were cost and incremental cost effectiveness ratios for the following: minutes of moderate-to-vigorous physical activity (MVPA) per day gained, MET hours gained per person/day; Body Mass Index (BMI) unit avoided; and 10 % reduction in BMI z-score. Results: The intervention cost AUD $329,952 over 24 months, or AUD$394 per student in the intervention group. This resulted in a cost effectiveness ratio of AUD$56 ($35-$147) per additional minute of MVPA, AUD$1 ($0.6-$2.7) per MET hour gained per person per day, AUD$1408 ($788-$6,570) per BMI unit avoided, and AUD$563 ($282-$3,942) per 10 % reduction in BMI z-score. Conclusion: PA4E1 is a cost effective intervention for increasing the physical activity levels and reducing unhealthy weight gain in adolescence, a period in which physical activity typically declines. Additional modelling could explore the potential economic impact of the intervention on morbidity and mortality. Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12612000382875.

© 2016 Society for Adolescent Health and Medicine. All rights reserved. Purpose: The aim of this study was to explore the effect of the Active Teen Leaders Avoiding Screen-time (ATLAS) intervention on psychological well-being in adolescent boys and to examine the potential mediating mechanisms that might explain this effect. Methods: ATLAS was evaluated using a cluster randomized controlled trial in 14 secondary schools located in low-income communities (N = 361 adolescent boys, mean age = 12.7 ±.5 years). The 20-week intervention was guided by self-determination theory and involved: professional development for teachers, provision of fitness equipment to schools, enhanced school sport sessions, researcher-led seminars, a smartphone application, and parental strategies for reducing screen time. Assessments were conducted at baseline and immediately post intervention (8 months). Psychological well-being was measured using the Flourishing Scale. Motivational regulations (intrinsic, identified, introjected, controlled, and amotivation) and basic psychological needs (autonomy, competence, and relatedness) in school sport, muscular fitness, resistance training skill competency, and recreational screen time were examined as potential mediating mechanisms of the intervention effect. Results: The intervention effect on well-being was small but statistically significant. Within a multiple mediator model, changes in autonomy needs satisfaction, recreational screen time, and muscular fitness significantly mediated the effect of the intervention on psychological well-being. Conclusions: In addition to the physical health benefits, targeted physical activity programs for adolescent boys may have utility for mental health promotion through the mechanisms of increasing autonomy support and muscular fitness and reducing screen time.

© 2016, The Author(s). Background: Gross motor competence confers health benefits, but levels in children and adolescents are low. While interventions can improve gross motor competence, it remains unclear which correlates should be targeted to ensure interventions are most effective, and for whom targeted and tailored interventions should be developed. Objective: The aim of this systematic review was to identify the potential correlates of gross motor competence in typically developing children and adolescents (aged 3¿18¿years) using an ecological approach. Methods: Motor competence was defined as gross motor skill competency, encompassing fundamental movement skills and motor coordination, but excluding motor fitness. Studies needed to assess a summary score of at least one aspect of motor competence (i.e., object control, locomotor, stability, or motor coordination). A structured electronic literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Six electronic databases (CINAHL Complete, ERIC, MEDLINE Complete, PsycINFO®, Scopus and SPORTDiscus with Full Text) were searched from 1994 to 5 August 2014. Meta-analyses were conducted to determine the relationship between potential correlates and motor competency if at least three individual studies investigated the same correlate and also reported standardized regression coefficients. Results: A total of 59 studies were identified from 22 different countries, published between 1995 and 2014. Studies reflected the full range of age groups. The most examined correlates were biological and demographic factors. Age (increasing) was a correlate of children¿s motor competence. Weight status (healthy), sex (male) and socioeconomic background (higher) were consistent correlates for certain aspects of motor competence only. Physical activity and sport participation constituted the majority of investigations in the behavioral attributes and skills category. Whilst we found physical activity to be a positive correlate of skill composite and motor coordination, we also found indeterminate evidence for physical activity being a correlate of object control or locomotor skill competence. Few studies investigated cognitive, emotional and psychological factors, cultural and social factors or physical environment factors as correlates of motor competence. Conclusion: This systematic review is the first that has investigated correlates of gross motor competence in children and adolescents. A strength is that we categorized correlates according to the specific ways motor competence has been defined and operationalized (object control, motor coordination, etc.), which enables us to have an understanding of what correlates assist what types of motor competence. Indeed our findings do suggest that evidence for some correlates differs according to how motor competence is operationalized.

© 2016 Elsevier Inc. Introduction The primary objective was to evaluate the impact of the ¿Switch-off 4 Healthy Minds¿ (S4HM) intervention on recreational screen-time in adolescents. Methods Cluster randomized controlled trial with study measures at baseline and 6-months (post-intervention). Eligible participants reported exceeding recreational screen-time recommendations (i.e., >¿2¿h/day). In total, 322 adolescents (mean age¿=¿14.4¿±¿0.6¿years) from eight secondary schools in New South Wales, Australia were recruited. The S4HM intervention was guided by Self-Determination Theory and included: an interactive seminar, eHealth messaging, a behavioral contract and parental newsletters. The primary outcome was recreational screen-time. Secondary outcomes included mental health (i.e., well-being, psychological distress, self-perceptions), objectively measured physical activity, and body mass index (BMI). Outcome analyses were conducted using linear mixed models and mediation was examined using a product-of-coefficients test. Results At post-intervention, significant reductions in screen-time were observed in both groups, with a greater reduction observed in the intervention group (-¿50¿min/day versus -¿29¿min, p¿<¿0.05 for both). However, the adjusted difference in change between groups was not statistically significant (mean¿=¿-¿21.3¿min/day, p¿=¿0.255). There were no significant intervention effects for mental health outcomes, physical activity or BMI. Significant mediation effects for autonomous motivation were found. Conclusions Participants in both the S4HM intervention and control groups significantly reduced their screen-time, with no group-by-time effects. Enhancing autonomous motivation might be a useful intervention target for trials aimed at reducing adolescents' recreational screen-time. Trial registration ACTRN12614000163606.

© 2016 The Author(s). Background: Obesity prevention interventions targeting 'at-risk' adolescents are urgently needed. The aim of this study is to evaluate the sustained impact of the 'Active Teen Leaders Avoiding Screen-time' (ATLAS) obesity prevention program. Methods: Cluster RCT in 14 secondary schools in low-income communities of New South Wales, Australia. Participants were 361 adolescent boys (aged 12-14 years) 'at risk' of obesity. The intervention was based on Self-Determination Theory and Social Cognitive Theory and involved: professional development, fitness equipment for schools, teacher-delivered physical activity sessions, lunch-time activity sessions, researcher-led seminars, a smartphone application, and parental strategies. Assessments for the primary (body mass index [BMI], waist circumference) and secondary outcomes were conducted at baseline, 8- (post-intervention) and 18-months (follow-up). Analyses followed the intention-to-treat principle using linear mixed models. Results: After 18-months, there were no intervention effects for BMI or waist circumference. Sustained effects were found for screen-time, resistance training skill competency, and motivational regulations for school sport. Conclusions: There were no clinically meaningful intervention effects for the adiposity outcomes. However, the intervention resulted in sustained effects for secondary outcomes. Interventions that more intensively target the home environment, as well as other socio-ecological determinants of obesity may be needed to prevent unhealthy weight gain in adolescents from low-income communities. Trial registration: Australian Clinical Trial Registry ACTRN12612000978864.

© 2016 The International Association of Applied Psychology Background: The purpose of this study was to experimentally examine the extent to which variety support in a resistance exercise program influences exercise-related well-being among inactive adults. Methods: A sample of 121 inactive university students were randomly assigned and participated in either a high or low variety support 6-week exercise program. Measures of exercise-related perceived variety, positive affect, negative affect, and subjective vitality were completed at baseline, after 3 weeks, and after 6 weeks (i.e. post-test). Results: Through use of structural equation¿modelling, the results showed that for those who completed measures at post-test (i.e. n = 55), and for all participants who received variety support (i.e. a modified intention-to-treat analysis; N = 121), exercise-related variety support indirectly explained higher levels of exercise-related positive affect, and subjective vitality, and lower levels of negative affect, through the mediating role of perceived variety. Conclusions: The provision of variety support in a resistance exercise program influences exercise-related well-being through perceptions of variety. Results are discussed in relation to the potential utility of providing variety support to promote exercise-related well-being in people who are physically inactive.

© 2015 Sports Medicine Australia. Objectives: To determine changes in maximal strength between two different resistance training progression models, linear (LP) and daily undulating (DUP), over a 12-week resistance training programme in sub-elite adolescent rugby union players. Design: The study used a quasi-experimental study design. Following baseline assessments, participants from Squad 1 were randomised to either LP or DUP; participants from Squad 2 formed a non-randomised comparison group (CON). Methods: Participants were 26 sub-elite adolescent rugby union players who were assessed at baseline and after 12 weeks. Outcomes included 5 repetition maximum (RM) box squat and bench press, height, body weight, skeletal muscle mass, percentage body fat and maturation status. Results: Participants in both the LP and DUP groups significantly increased their squat and bench press strength from baseline to 12 weeks. There were no significant differences between groups for squat and bench press increases after 12 weeks (p > 0.05). No significant increases in squat or bench press strength were observed after 12 weeks in the CON group. Increases in lower body strength were large in the LP group (ES: 1.64) and very large in the DUP group (ES: 2.33). Upper body strength changes were small in both groups (LP, ES: 0.57; DUP, ES: 0.31). Conclusions: Twelve weeks of LP or DUP resistance training are both effective at increasing maximal lower and upper body strength in adolescent rugby athletes. Additionally, twice weekly frequency of resistance training in adolescent rugby athletes with greater than 6-months resistance training experience is sufficient to elicit substantial increases in maximal strength.

© Copyright 2016 by the American College of Sports Medicine. Purpose Emerging literature suggests that physical activity and fitness may have a positive effect on cognitive and mental health in adolescents. The purpose of the current study was to evaluate the efficacy of two high-intensity interval training (HIIT) protocols for improving cognitive and mental health outcomes (executive function, psychological well-being, psychological distress, and physical self-concept) in adolescents. Methods Participants (n = 65; mean age = 15.8 ± 0.6 yr) were randomized to three conditions: aerobic exercise program (AEP; n = 21), resistance and aerobic program (RAP; n = 22), and control (n = 22). HIIT sessions (8-10 min per session) were delivered during physical education lessons or at lunchtime three times per week for 8 wk. Assessments were conducted at baseline and immediately postintervention to detect changes in executive function (trail making test), psychological well-being, psychological distress, and physical self-description by researchers blinded to treatment allocation. Intervention effects were examined using linear mixed models. Cohen's d effect sizes and clinical inference were also calculated. Results While results were not significant, small improvements in executive function (mean change (95% CI) -6.69 (-22.03, 8.64), d = -0.32) and psychological well-being (mean change (95% CI) 2.81 (-2.06, 7.68), d = 0.34) were evident in the AEP group; and moderate improvements in executive function (mean change (95% CI) -10.73 (-26.22, 4.76), d = -0.51), and small improvements in well-being (mean change (95% CI) 2.96 (-1.82, 7.75), d = 0.36) and perceived appearance (mean change (95% CI) 0.32 (-0.25, 0.86), d = 0.35), were observed for the RAP group. Mean feeling state scores improved from preworkout to postworkout in both HIIT conditions, with significant results for the AEP (P = 0.001). Conclusions This study highlights the potential of embedding HIIT within the school day for improving cognitive and mental health among adolescents.

© 2016 Taylor & Francis. Objective: More evidence from prospective studies is needed to determine ¿if¿ and ¿how¿ social cognitive constructs mediate behaviour change. In a longitudinal study, we aimed to examine potential social cognitive mediators of objectively measured physical activity (PA) behaviour among people with type 2 diabetes (T2D) who participated in a six-month PA intervention. Methods: All participants from the proven effective Healthy Eating and Active Living for Diabetes in Primary Care Networks trial were included for this secondary analysis. Change in pedometer-derived daily step counts (baseline to six months) was the outcome of interest. Primary constructs of interest were from Social Cognitive Theory, however constructs from and Theory of Planned Behaviour were also tested in a mediating variable framework using a product-of-coefficients test. Results: The sample (N¿=¿198) had a mean age of 59.5 (SD 8.3) years, haemoglobin A1c 6.8% (SD 1.1), 50% women, BMI 33.6¿kg/m2 (SD 6.5), systolic pressure 125.6¿mmHg (SD 16.2) and average daily steps were 5879 (SD 3130). Daily pedometer-determined steps increased for the intervention group compared to usual care control at six-months (1481 [SD 2631] vs. 336 [SD 2712]; adjusted p¿=¿.002). There was a significant action theory test effect for ¿planning¿ (A¿=¿.21, SE¿=¿.10, p¿=¿.037), and significant conceptual theory test results for ¿subjective norms¿ (B¿=¿657, SE¿=¿312, p¿=¿.037) and ¿cons¿ (B¿=¿-664, SE¿=¿270, p¿=¿.015). None of the constructs satisfied the criteria for mediation. Conclusions: We were unable to account for the effect of a pedometer-based PA intervention for people with T2D through our examination of mediators. Our findings are inconsistent with some literature concerning PA interventions in diabetes; this may be due to variability in measures used or in study populations.

This article presents a conceptual model illustrating a targeted approach to the design and delivery of health behavior interventions that focus on physical activity promotion. We hypothesize that researchers who i) enhance the sociocultural relevance of their core intervention components and ii) recognize the unique contributions of both intervention design and delivery will experience greater intervention engagement and improved outcomes.

© 2016 Elsevier Inc. Background: School-based trials to prevent and reduce prevalence of pediatric obesity in low-income countries are necessary. In Brazil, addressing adolescent obesity is a public health priority. Objective: To evaluate the impact of a group randomized controlled trial involving a 6-month multicomponent school-based obesity prevention program targeting adolescent girls. Methods: The Healthy Habits, Healthy Girls-Brazil program recruited participants (n = 253; 16.05 ± 0.05 years) from ten eligible public technical schools in São Paulo, Brazil. The program was adapted from an Australian intervention study, which is based on the Social Cognitive Theory. The primary outcome measure was body mass index (BMI), and secondary outcomes included BMI z score, waist circumference, and various sedentary and dietary health-related behaviours. Results: Although changes in BMI were not statistically significant, differences favored the intervention group (adjusted mean difference, -0.26 kg/m2,se SE = 0.018, p = 0.076). Statistically significant intervention effects were found for waist circumference (-2.28 cm; p =, p = 0.01), computer screen time on the weekends (0.63 h/day, p; p = 0.02), total sedentary activities on the weekends (-0.92 h/day, p < 0.01), and vegetable intake (1.16 servings/day, p = 0.01). Conclusion: These findings provide some evidence for the benefit of a school-based intervention to prevent unhealthy weight gain in adolescent girls living in low-income communities.

© 2016 World Obesity. Summary: Sedentary behaviour has emerged as a unique determinant of health in adults. Studies in children and adolescents have been less consistent. We reviewed the evidence to determine if the total volume and patterns (i.e. breaks and bouts) of objectively measured sedentary behaviour were associated with adverse health outcomes in young people, independent of moderate-intensity to vigorous-intensity physical activity. Four electronic databases (EMBASE MEDLINE, Ovid EMBASE, PubMed and Scopus) were searched (up to 12 November 2015) to retrieve studies among 2- to 18-year-olds, which used cross-sectional, longitudinal or experimental designs, and examined associations with health outcomes (adiposity, cardio-metabolic, fitness, respiratory, bone/musculoskeletal, psychosocial, cognition/academic achievement, gross motor development and other outcomes). Based on 88 eligible observational studies, level of evidence grading and quantitative meta-analyses indicated that there is limited available evidence that the total volume or patterns of sedentary behaviour are associated with health in children and adolescents when accounting for moderate-intensity to vigorous-intensity physical activity or focusing on studies with low risk of bias. Quality evidence from studies with robust designs and methods, objective measures of sitting, examining associations for various health outcomes, is needed to better understand if the overall volume or patterns of sedentary behaviour are independent determinants of health in children and adolescents.

© 2016 Human Kinetics, Inc. To evaluate the impact of a primary school-based physical activity (PA) integration program delivered by teachers on objectively measured PA and key educational outcomes. Methods: Ten classes from 8 Australian public schools were randomly allocated to treatment conditions. Teachers from the intervention group were taught to embed movement-based learning in their students' (n = 142) daily mathematics program in 3 lessons per week for 6 weeks. The control group (n = 98) continued its regular mathematics program. The primary outcome was accelerometer-determined PA across the school day. Linear mixed models were used to analyze treatment effects. Results: Significant intervention effects were found for PA across the school day (adjusted mean difference 103 counts per minute [CPM], 95% confidence interval [CI], 36.5-169.7, P =.008). Intervention effects were also found for PA (168 CPM, 95% CI, 90.1-247.4, P =.008) and moderate-to-vigorous PA (2.6%, 95% CI, 0.9-4.4, P =.009) in mathematics lessons, sedentary time across the school day (-3.5%, 95% CI,-7.0 to-0.13, P =.044) and during mathematics (-8.2%, CI,-13.0 to-2.0, P =.010) and on-task behavior (13.8%, 95% CI, 4.0-23.6, P =.011)-but not for mathematics performance or attitude. Conclusion: Integrating movement across the primary mathematics syllabus is feasible and efficacious.

© 2016 Elsevier Ltd. Objectives: To investigate the effectiveness of the CrossFit¿ Teens resistance training program for improving mental health outcomes in adolescents, and to explore potential moderators and mediators. Design: Assessor-blinded randomized controlled trial. Methods: Ninety-six students (15.4 (0.5) years, 51.5% female) from one NSW secondary school, Australia 2013, were randomized into the 8-week CrossFit¿ Teens intervention (n = 51) or control conditions (n = 45). Measures of mental health (psychological distress and self-esteem) were assessed using the Strength and Difficulties Questionnaire and Physical Self-Description Questionnaire. Hypothesized mediators were perceived body fat, strength and appearance; and general physical self-concept. Mediation was assessed using Preacher and Hayes' multiple mediation regression SPSS macro. Hypothesized moderators (sex and baseline levels of psychological distress) were assessed using linear mixed models and Cohen's d effect sizes were evaluated. Results: There were no significant intervention effects on mental health or potential mediators in the full study sample. Intervention participants categorized as 'at risk' of psychological distress demonstrated improvements in self-esteem (d = 1.35); perceived body fat (d = 1.05), perceived appearance (d = 0.95); physical self-concept (d = 1.96); and total difficulties score (d = 0.70). A medium-large positive effect on perceived body fat was also observed in boys. Conclusions: Participation in the CrossFit¿ Teens resistance training program did not improve mental health outcomes in the full study sample. However, the results from this study provides preliminary evidence for improving mental health in adolescents 'at risk' of developing psychological disorders.Trial Registration No: ACTRN12611000976987.

© 2015, Springer Science+Business Media New York. The purpose of this study was to examine the extent to which the provision of variety (i.e., variety support) is related to exercise behavior among physically inactive adults and the extent to which the ¿experience of variety¿ mediates those effects. One hundred and twenty one inactive university students were randomly assigned to follow a high or low variety support exercise program for 6¿weeks. Assessments were conducted at baseline, 3- and 6-weeks. Participants in the high variety support condition displayed higher levels of adherence to the exercise program than those in the low variety support condition [F(1, 116)¿=¿5.55, p¿=¿.02, ¿p2¿=¿.05] and the relationship between variety support and adherence was mediated by perceived variety (ß¿=¿.16, p¿<¿.01). Exercise-related variety support holds potential to be an efficacious method for facilitating greater exercise adherence behaviors of previously inactive people by fostering perceptions of variety.

© 2015 Taylor & Francis. The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered ¿at-risk¿ of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.

© 2014. Objectives: Physical education (PE) plays an important role in contributing to students' physical activity (PA); however, moderate-to-vigorous PA (MVPA) within PE is lower than recommended. Little is known about the PA levels of students from disadvantaged schools within PE. This study aimed to describe: (i) the PA levels of students from disadvantaged secondary schools during PE lessons, (ii) the lesson context and teacher interactions occurring during PE, and (iii) the associations between teacher, school or PE lesson characteristics with student physical activity levels in PE. Design: Cross-sectional study of 100 Grade 7 PE lessons across 10 secondary schools. Methods: System for observing fitness instruction time (SOFIT) was used to assess student PA, lesson context, and teacher interaction. Teacher and school characteristics were collected via survey. Mean proportion of lesson time was used to describe PA, lesson context and teacher interaction. Associations between each outcome variable and each characteristic were examined using 2-sample t-tests, ANOVAs and linear regression. Results: Thirty-nine percent of PE lesson was spent in MVPA, and less than 10% spent in VA. Lessons in schools in urban areas included significantly more MVPA than rural areas (P = 0.04). Male teachers and more experienced teachers conducted lessons with significantly more VA than female and less experienced teachers (P = 0.04 and 0.02). MVPA was also higher in lessons conducted by more experienced teachers. Conclusions: PA during PE lessons within disadvantaged secondary schools is below international recommendations. Male teachers, more experienced teachers and schools in urban regions teach more active lessons.

Background: Adolescence is a recognised period of physical activity decline, particularly among low-income communities. We report the 12-month (midpoint) effects of a 2-year multicomponent physical activity intervention implemented in disadvantaged secondary schools. Methods: A cluster randomised trial was undertaken in 10 secondary schools located in disadvantaged areas in New South Wales, Australia. Students in Grade 7 were recruited, with follow-up in Grade 8. The intervention was guided by socioecological theory and included seven physical activity strategies, and six implementation adoption strategies. The primary outcome was mean minutes of moderate-to-vigorous physical activity (MVPA) per day assessed using Actigraph GT3X accelerometers. Outcome data were analysed using repeated measures linear mixed models. Results: At baseline, 1150 (93%) students participated in the data collection (mean age 12 years, 48% boys) and 1050 (79%) students participated at 12-month follow-up. By the 12-month follow-up, the six implementation adoption strategies had been used to support schools to deliver four of the seven physical activity elements. There was a significant group-by-time interaction for mean minutes of MVPA per day in favour of the intervention group (adjusted difference between groups at follow-up=3.85 min, 95% CI (0.79 to 6.91), p=0.01), including significantly more vigorous physical activity (2.45 min, p=0.01), equating to 27 min more MVPA per week. Summary: At 12-month follow-up, the intervention had reduced the decline in physical activity among adolescents from disadvantaged schools. The intervention may assist students to meet physical activity guidelines.

© 2015, © The Author(s) 2015. The primary objective of this study was to evaluate the efficacy of a pilot intervention using a gamecentered approach for improvement of physical activity (PA) and physical education (PE) outcomes simultaneously, and if this had an impact on enjoyment of PE. A group-randomized controlled trial with a 7-week wait-list control group was conducted in one primary school in the Hunter Region, NSW, Australia. Participants (n<107 students; mean age<10.7 years, SD 0.87) were randomized by class group into the Professional Learning for Understanding Games Education (PLUNGE) pilot intervention (n<52 students) or the control (n<55) conditions. PLUNGE involved 6 × 60 min PE lessons based on game-centered curriculum delivered via an in-class teacher mentoring program. Students were assessed at baseline and 7-week follow-up for fundamental movement skills (FMS) of throw and catch, game play abilities of decision making, support and skill performance; in-class PA; and enjoyment of PA. Linear mixed models revealed significant group-by-time intervention effects (p = 0.05) for throw (effect size: d<0.9) and catch (d<0.4) FMS, decision making (d<0.7) and support (d<0.9) during game play, and in-class PA (d<1.6). No significant intervention effects (p = 0.05) were observed for skills outcome during game play (d<¿0.2) or student enjoyment (d<0.1). Game-centered pedagogy delivered via a teacher professional learning program was efficacious in simultaneously improving students¿ FMS skills, in-class PA and their decision making and support skills in game play.

© 2015. Current physical activity and fitness levels among adolescents are low, increasing the risk of chronic disease. Although the efficacy of high intensity interval training (HIIT) for improving metabolic health is now well established, it is not known if this type of activity can be effective to improve adolescent health. The primary aim of this study is to assess the effectiveness and feasibility of embedding HIIT into the school day. A 3-arm pilot randomized controlled trial was conducted in one secondary school in Newcastle, Australia. Participants (n= 65; mean age = 15.8(0.6) years) were randomized into one of three conditions: aerobic exercise program (AEP) (n = 21), resistance and aerobic exercise program (RAP) (n = 22) and control (n = 22). The 8-week intervention consisted of three HIIT sessions per week (8-10. min/session), delivered during physical education (PE) lessons or at lunchtime. Assessments were conducted at baseline and post-intervention to detect changes in cardiorespiratory fitness (multi-stage shuttle-run), muscular fitness (push-up, standing long jump tests), body composition (Body Mass Index (BMI), BMI-z scores, waist circumference) and physical activity motivation (questionnaire), by researchers blinded to treatment allocation. Intervention effects for outcomes were examined using linear mixed models, and Cohen's d effect sizes were reported. Participants in the AEP and RAP groups had moderate intervention effects for waist circumference (p = 0.024), BMI-z (p = 0.037) and BMI (not significant) in comparison to the control group. A small intervention effect was also evident for cardiorespiratory fitness in the RAP group.

© 2014, The Society of Behavioral Medicine. Background: Little is known about which behavioral strategies are most important to target in weight loss interventions for men. Purpose: The aim of the current study was to identify behavioral mediators of weight loss in the male-only Self-Help, Exercise, and Diet using Information Technology (SHED-IT) community weight loss study. Methods: A randomized controlled trial with 159 overweight/obese men [mean (SD) age = 47.5 (11.0) years; body mass index = 32.7 (3.5) kg/m2] assessed at baseline, 3¿months (post-test) and 6¿months (follow-up). Results: In an intention-to-treat, multiple-mediator model, the significant intervention effect on weight at 6¿months (-3.70¿kg; p < 0.001) was mediated by increases in physical activity (steps/day) and decreases in takeaway meals (kJ/day) and portion size at 3¿months. The largest mediation effect was for physical activity (-0.6¿kg; 95¿% confidence interval -1.4, -0.1). Overall, the targeted mediators accounted for 47.0¿% of the intervention¿s effect on weight. Conclusion: Step counts, takeaway food consumption, and portion sizes may be key areas to target in future weight loss programs for men (ACTRN12610000699066).

© Br J Sports Med 2015. Background: High-intensity interval training (HIIT) may be a feasible and efficacious strategy for improving health-related fitness in young people. The objective of this systematic review and meta-analysis was to evaluate the utility of HIIT to improve health-related fitness in adolescents and to identify potential moderators of training effects. Methods: Studies were considered eligible if they: (1) examined adolescents (13-18 years); (2) examined health-related fitness outcomes; (3) involved an intervention of =4 weeks in duration; (4) included a control or moderate intensity comparison group; and (5) prescribed high-intensity activity for the HIIT condition. Meta-analyses were conducted to determine the effect of HIIT on health-related fitness components using Comprehensive Meta-analysis software and potential moderators were explored (ie, study duration, risk of bias and type of comparison group). Results: The effects of HIIT on cardiorespiratory fitness and body composition were large, and medium, respectively. Study duration was a moderator for the effect of HIIT on body fat percentage. Intervention effects for waist circumference and muscular fitness were not statistically significant. Conclusions: HIIT is a feasible and time-efficient approach for improving cardiorespiratory fitness and body composition in adolescent populations.

© 2014, © 2014 The Author(s). 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.

© 2015, Springer International Publishing Switzerland. Background: It has been suggested that young people should develop competence in a variety of ¿lifelong physical activities¿ to ensure that they can be active across the lifespan. Objective: The primary aim of this systematic review is to report the methodological properties, validity, reliability, and test duration of field-based measures that assess movement skill competency in lifelong physical activities. A secondary aim was to clearly define those characteristics unique to lifelong physical activities. Data Sources: A search of four electronic databases (Scopus, SPORTDiscus, ProQuest, and PubMed) was conducted between June 2014 and April 2015 with no date restrictions. Study Selection: Studies addressing the validity and/or reliability of lifelong physical activity tests were reviewed. Included articles were required to assess lifelong physical activities using process-oriented measures, as well as report either one type of validity or reliability. Study Appraisal and Synthesis Methods: Assessment criteria for methodological quality were adapted from a checklist used in a previous review of sport skill outcome assessments. Results: Movement skill assessments for eight different lifelong physical activities (badminton, cycling, dance, golf, racquetball, resistance training, swimming, and tennis) in 17 studies were identified for inclusion. Methodological quality, validity, reliability, and test duration (time to assess a single participant), for each article were assessed. Moderate to excellent reliability results were found in 16 of 17 studies, with 71¿% reporting inter-rater reliability and 41¿% reporting intra-rater reliability. Only four studies in this review reported test¿retest reliability. Ten studies reported validity results; content validity was cited in 41¿% of these studies. Construct validity was reported in 24¿% of studies, while criterion validity was only reported in 12¿% of studies. Limitations: Numerous assessments for lifelong physical activities may exist, yet only assessments for eight lifelong physical activities were included in this review. Generalizability of results may be more applicable if more heterogeneous samples are used in future research. Conclusion: Moderate to excellent levels of inter- and intra-rater reliability were reported in the majority of studies. However, future work should look to establish test¿retest reliability. Validity was less commonly reported than reliability, and further types of validity other than content validity need to be established in future research. Specifically, predictive validity of ¿lifelong physical activity¿ movement skill competency is needed to support the assertion that such activities provide the foundation for a lifetime of activity.

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

© 2014 Elsevier Inc. Introduction: Excessive recreational screen time (i.e., screen use for entertainment) is a global public health issue associated with adverse mental and physical health outcomes. Considering the growing popularity of screen-based recreation in adolescents, there is a need to identify effective strategies for reducing screen time among adolescents. The aim of this paper is to report the rationale and study protocol for the 'Switch-off 4 Healthy Minds' (S4HM) study, an intervention designed to reduce recreational screen time among adolescents. Methods: The S4HM intervention will be evaluated using a cluster randomized controlled trial in eight secondary schools (. N=. 322 students) in New South Wales, Australia. The 6-month multi-component intervention will encourage adolescents to manage their recreational screen time using a range of evidence-based strategies. The intervention is grounded in Self-Determination Theory (SDT) and includes the following components: an interactive seminar for students, eHealth messaging, behavioral contract and parental newsletters. All outcomes will be assessed at baseline and at 6-months (i.e., immediate post-test). The primary outcome is recreational screen time measured by the Adolescent Sedentary Activity Questionnaire (ASAQ). Secondary outcomes include: self-reported psychological well-being, psychological distress, global physical self-concept, resilience, pathological video gaming and aggression, and objectively measured physical activity (accelerometry) and body mass index (BMI). Hypothesized mediators of behavior change will also be explored. Discussion: The S4HM study will involve the evaluation of an innovative, theory-driven, multi-component intervention that targets students and their parents and is designed to reduce recreational screen time in adolescents. The intervention has been designed for scalability and dissemination across Australian secondary schools.

© 2014, The Author(s). Purpose: Little is known about how to improve and create sustainable lifestyle behaviors of cancer survivors. Interventions based on social cognitive theory (SCT) have shown promise. This review examined the effect of SCT-based physical activity and nutrition interventions that target cancer survivors and identified factors associated with their efficacy. Methods: A systematic search of seven databases identified randomized controlled trials that (i) targeted adult cancer survivors (any point from diagnosis); (ii) reported a primary outcome of physical activity, diet, or weight management; and (iii) included an SCT-based intervention targeting physical activity or diet. Qualitative synthesis and meta-analysis were conducted. Theoretical constructs and intervention characteristics were examined to identify factors associated with intervention efficacy. Results: Eighteen studies (reported in 33 publications) met review inclusion criteria. Meta-analysis (n = 12) revealed a significant intervention effect for physical activity (standardized mean difference (SMD) = 0.33; P < 0.01). Most studies (six out of eight) that targeted dietary change reported significant improvements in at least one aspect of diet quality. No SCT constructs were associated with intervention effects. There were no consistent trends relating to intervention delivery method or whether the intervention targeted single or multiple behaviors. Conclusions: SCT-based interventions demonstrate promise in improving physical activity and diet behavior in cancer survivors, using a range of intervention delivery modes. Further work is required to understand how and why these interventions offer promise for improving behavior. Implications for Cancer Survivors: SCT-based interventions targeting diet or physical activity are safe and result in meaningful changes to diet and physical activity behavior that can result in health improvements.

© 2015 Human Kinetics, Inc. Background: This study examined potential parenting-related mediators of children's physical activity and dietary behavior change in the Healthy Dads, Healthy Kids (HDHK) community program. Methods: A randomized controlled trial was conducted with 45 overweight/obese (mean [SD] age = 39.8 [5.4] years; BMI = 32.4 [3.8]) fathers and their children (n = 77; 58% boys; mean [SD] age = 7.7 [2.5] years). Families were randomized to either the HDHK program or wait-list control group. The program involved 7 sessions. Fathers and their children were assessed at baseline and at 14 weeks for physical activity (pedometery) and core food intake (Questionnaire). Fathers' lifestyle-related parenting practices included; self-efficacy, beliefs, modeling, logistic support, rules, cophysical activity, shared mealtime frequency and intentions. Results: Significant intervention effects were found for cophysical activity and modeling physical activity. Cophysical activity mediated children's physical activity in the intervention ('mediated effect,' AB = 653, 95% CI = 4-2050) and was responsible for 59.5% of the intervention effect. Fathers' beliefs mediated children's percent energy from core foods (AB = 1.51, 95% CI = 0.05-5.55) and accounted for 72.9% of the intervention effect. Conclusions: Participation in the HDHK program positively impacted on fathers' cophysical activity with their child and beliefs about healthy eating which mediated changes in children's diet and physical activity behaviors.

© 2015 James et al. Background: Physical activity and consuming a healthy diet have clear benefits to the physical and psychosocial health of cancer survivors, with guidelines recognising the importance of these behaviors for cancer survivors. Interventions to promote physical activity and improve dietary behaviors among cancer survivors and carers are needed. The aim of this study was to determine the effects of a group-based, face-to-face multiple health behavior change intervention on behavioral outcomes among cancer survivors of mixed diagnoses and carers. Methods: The Exercise and Nutrition Routine Improving Cancer Health (ENRICH) intervention was evaluated using a two-group pragmatic randomized controlled trial. Cancer survivors and carers (n=174) were randomly allocated to the face-to-face, group-based intervention (six, theory-based two-hour sessions delivered over 8weeks targeting healthy eating and physical activity [PA]) or wait-list control (after completion of 20-week data collection). Assessment of the primary outcome (pedometer-assessed mean daily step counts) and secondary outcomes (diet and alcohol intake [Food Frequency Questionnaire], self-reported PA, weight, body mass index, and waist circumference) were assessed at baseline, 8-and 20-weeks. Results: There was a significant difference between the change over time in the intervention group and the control group. At 20weeks, the intervention group had increased by 478 steps, and the control group had decreased by 1282 steps; this represented an adjusted mean difference of 1761 steps (184 to 3337; P=0.0028). Significant intervention effects for secondary outcomes, included a half serving increase in vegetable intake (difference 39g/day; 95% CI: 12 to 67; P=0.02), weight loss (kg) (difference -1.5kg; 95% CI, -2.6 to -0.3; P=0.014) and change in body mass index (kg/m2) (difference -0.55kg/m2; 95% CI, -0.97 to -0.13; P=0.012). No significant intervention effects were found for self-reported PA, total sitting time, waist circumference, fruit, energy, fibre, alcohol, meat, or fat consumption. Conclusions: The ENRICH intervention was effective for improving PA, weight, body mass index, and vegetable consumption even with the inclusion of multiple cancer types and carers. As an example of successful research translation, the Cancer Council NSW has subsequently adopted ENRICH as a state-wide program. Trial registration: Australian New Zealand Clinical Trials Register identifier: ANZCTRN1260901086257.

Background Evidence suggests that physical self-concept is associated with physical activity in children and adolescents, but no systematic review of this literature has been conducted. Objective The primary aim of this systematic review and meta-analysis was to determine the strength of associations between physical activity and physical self-concept (general and sub-domains) in children and adolescents. The secondary aim was to examine potential moderators of the association between physical activity and physical self-concept. Methods A systematic search of six electronic databases (MEDLINE, CINAHL, SPORTDiscus, ERIC, Web of Science and Scopus) with no date restrictions was conducted. Random effects meta-analyses with correction for measurement were employed. The associations between physical activity and general physical self-concept and sub-domains were explored. A risk of bias assessment was conducted by two reviewers. Results The search identified 64 studies to be included in the meta-analysis. Thirty-three studies addressed multiple outcomes of general physical self-concept: 28 studies examined general physical self-concept, 59 examined perceived competence, 25 examined perceived fitness, and 55 examined perceived appearance. Perceived competence was most strongly associated with physical activity (r = 0.30, 95 % CI 0.24-0.35, p < 0.001), followed by perceived fitness (r = 0.26, 95 % CI 0.20-0.32, p < 0.001), general physical self-concept (r = 0.25, 95 % CI 0.16-0.34, p < 0.001) and perceived physical appearance (r = 0.12, 95 % CI 0.08-0.16, p < 0.001). Sex was a significant moderator for general physical self-concept (p < 0.05), and age was a significant moderator for perceived appearance (p = 0.01) and perceived competence (p < 0.05). No significant moderators were found for perceived fitness. Conclusion Overall, a significant association has been consistently demonstrated between physical activity and physical self-concept and its various sub-domains in children and adolescents. Age and sex are key moderators of the association between physical activity and physical self-concept. © 2014 Springer International Publishing Switzerland.

© 2014 The Foundation for Professionals in Services for Adolescents. The primary aim of this study was to examine the association between the types of video games played by adolescent boys and their participation in physical activity and recreational screen-time. Participants were 320 boys (mean age=12.7, ±0.5 years) from 14 secondary schools located in low-income areas of New South Wales, Australia. Outcomes included height, weight, physical activity (accelerometers), total screen-time, and video game genre preference. Significant differences in both weekday and weekend screen-time were found between video game genre groups. In addition, significant differences in overall activity and moderate-to-vigorous physical activity were found between genre groups on weekdays. Between-group differences in physical activity on weekends were not statistically significant. This cross-sectional study has demonstrated that video game genre preference is associated with physical activity and screen-time in adolescent boys from low-income communities.

Objective: To evaluate the effectiveness of the 'Healthy Dads, Healthy Kids (HDHK)' program when delivered by trained facilitators in community settings. Method: A two-arm randomized controlled trial of 93 overweight/obese fathers (mean [SD] age=40.3 [5.3] years; BMI=32.5 [3.8] kg/m2) and their primary school-aged children (n=132) from the Hunter Region, Australia. In 2010-2011, families were randomized to either: (i) HDHK intervention (n=48 fathers, n=72 children) or (ii) wait-list control group. The 7-week intervention included seven sessions and resources (booklets, pedometers). Assessments were held at baseline and 14-weeks with fathers' weight (kg) as the primary outcome. Secondary outcomes for fathers and children included waist, BMI, blood pressure, resting heart rate, physical activity (pedometry), and self-reported dietary intake and sedentary behaviors. Results: Linear mixed models (intention-to-treat) revealed significant between-group differences for fathers' weight (P < .001, d= 0.24), with HDHK fathers losing more weight (- 3.3. kg; 95%CI, - 4.3, - 2.4) than control fathers (0.1. kg; 95%CI, - 0.9,1.0). Significant treatment effects (P < .05) were also found for fathers' waist (d= 0.41), BMI (d= 0.26), resting heart rate (d= 0.59), energy intake (d= 0.49) and physical activity (d= 0.46) and for children's physical activity (d= 0.50) and adiposity (d= 0.07). Discussion: HDHK significantly improved health outcomes and behaviors in fathers and children, providing evidence for program effectiveness when delivered in a community setting. © 2014 Published by Elsevier Inc.

Objective: Self-determination theory is used as a framework for examining the relation between motivation and physical activity. The purpose of this review was to systematically review studies that assessed the association between self-determined motivation and physical activity levels in children and adolescents. Method: We searched electronic databases in April 2013. Included studies assessed the relation between motivation (as outlined in self-determination theory) and physical activity in children and adolescents. Results: Forty-six studies ( n=15,984 participants) met the inclusion criteria. Meta-analysis indicated that overall levels of self-determined motivation had a weak to moderate, positive associations with physical activity ( ¿=.21 to .31). Autonomous forms of motivation (i.e., intrinsic motivation and identified regulation) had moderate, positive associations with physical activity ( ¿=.27 to .38), whereas controlled forms of motivation (i.e., introjection and external regulation) had weak, negative associations with physical activity ( ¿=.03 to 17). Amotivation had a weak, negative association with physical activity ( ¿=.11 to 21). Conclusions: Evidence provides some support for self-determination theory tenets. However, there was substantial heterogeneity in most associations and many studies had methodological shortcomings. © 2014.

Background: There is emerging evidence for positive associations between physical activity (PA), fitness, and fundamental movement skill (FMS) competence, for both children and adolescents. Current reviews of interventions to improve these variables note few studies conduct follow-up assessments to assess behavior maintenance. Objective: The aim of this systematic review was to determine whether typically developing children and adolescents (aged 3-18 years) who have participated in school-based interventions have sustained outcomes in PA, fitness, and/or FMS. Methods: A systematic search of six electronic databases (CINAHL® Plus with Full Text, Ovid MEDLINE®, SPORTDiscus¿, Scopus, PsycINFO® and ERIC) was conducted from 1995 to 26 July 2012. Included studies were school-based studies (including randomized controlled trials, longitudinal cohort, quasi-experimental, and experimental) that had a positive effect at post intervention in at least one variable and had a follow-up PA, fitness, or FMS assessment at least 6 months after the post-intervention assessment. Risk of bias assessment was guided by the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" statement. Results: The search identified 14 articles, and some studies addressed multiple outcomes: 13 articles assessed PA; three assessed fitness; and two assessed FMS. No study in this review met four key methodological criteria that have been shown to influence results, i.e., clarity on the randomization process, assessor blinding, analyzing participants in their original groups, and retaining sufficient participants through the entire study. Three-quarters (ten of 13) of the studies addressing PA, reported PA behavior change maintenance. The length of follow-up ranged from 6 months to 20 years, and the degree of PA difference reported was between 3 and 14 min per day. Only one of the three studies assessing fitness reported a sustained impact, whilst both studies that assessed FMS reported maintenance of effects. Conclusion: It is likely that PA is a sustainable outcome from interventions in children and adolescents, and there is reasonable evidence that interventions of longer than 1 year and interventions that utilize a theoretical model or framework are effective in producing this sustained impact. It would seem probable that FMS are a sustainable outcome in children and adolescents; however, this finding should be viewed with caution given the lack of studies and the risk of bias assessment. More research is needed to assess the sustainability of fitness interventions as this review only included a handful of studies that addressed fitness and only one of these studies found a sustained impact. © 2013 Springer International Publishing Switzerland.

The primary aim of this study was to examine a range of potential behavioral and maternal/paternal correlates of adiposity in children. Secondary aims were to examine (a) correlates of screen-time, diet and physical activity and (b) if there were differences in maternal and paternal physical activity- and dietary-related parenting practices. Cross-sectional analysis was conducted using 70 families with children (59% boys (41/70), mean age 8.4 (±2.4) years). Parenting practices were measured using the Parenting Strategies for Eating and Activity Scale. Children's outcomes included: 7-day pedometry (physical activity), screen-time, percent energy from core foods (Food frequency questionnaire) and BMI z-score. Multiple regression models were generated to examine the associations between maternal and paternal parenting practices and children's variables. In the regression analyses, fathers' BMI (p < .01) and mothers' control (p < .001) were significantly associated with child weight status. Fathers' reinforcement (p < .01) was significantly associated with child physical activity. For screen-time, mothers' monitoring (p < .001) and child characteristics [age (p = .01), sex (p = .01), BMI z-score (p = .03)] were significant predictors. Mothers' parenting practices [limit setting (p = .01), reinforcement (p = .02)] and child screen-time (p = .02) were significantly associated with intake of core foods. Despite some similarities within families, three out of five parenting constructs were significantly different between mothers and fathers. Mothers and fathers have different parental influences on their children's weight status and lifestyle behaviors and both should be included in lifestyle interventions targeting children. A focus on maternal parenting specifically relating to screen-time and diet, and father's physical activity parenting and weight status may support their children in developing more healthy behaviors. © 2014 Elsevier Ltd.

© 2014 The Authors. Objectives The aim was to evaluate the impact of the 'Healthy Dads, Healthy Kids' programme on fathers' and mothers' activity- and diet-related parenting practices. Methods Overweight/obese fathers (n = 87) and their primary school-aged children (56% boys) were randomized to either (i) 7-week programme (n = 45) or (ii) control group (n = 42). The programme involved four sessions for fathers only and three for fathers/children. Mothers were not directly involved. Parenting practices of both fathers and mothers were measured using the parenting strategies for eating and activity scale at baseline and 14-week follow-up. Results Intention-to-treat analysis using linear mixed models revealed significant group-by-time effects for fathers' limit setting (P = 0.048, d = 0.36) and reinforcement for multiple lifestyle behaviours (P = 0.001, d = 0.79). No significant intervention effects were found for fathers' control, monitoring, discipline or mothers' parenting practices (P > 0.05). Conclusions The Healthy Dads, Healthy Kids programme had a positive impact on some parenting practices for fathers but not mothers.

The aim of this study was to describe the development and assess test-retest reliability and construct validity of the Resistance Training Skills Battery (RTSB) for adolescents. The RTSB provides an assessment of resistance training skill competency and includes 6 exercises (i.e., body weight squat, push-up, lunge, suspended row, standing overhead press, and front support with chest touches). Scoring for each skill is based on the number of performance criteria successfully demonstrated. An overall resistance training skill quotient (RTSQ) is created by adding participants' scores for the 6 skills. Participants (44 boys and 19 girls, mean age = 14.5 ± 1.2 years) completed the RTSB on 2 occasions separated by 7 days. Participants also completed the following fitness tests, which were used to create a muscular fitness score (MFS): handgrip strength, timed push-up, and standing long jump tests. Intraclass correlation (ICC), paired samples t-tests, and typical error were used to assess test-retest reliability. To assess construct validity, gender and RTSQ were entered into a regression model predicting MFS. The rank order repeatability of the RTSQ was high (ICC = 0.88). The model explained 39% of the variance in MFS (p = 0.001) and RTSQ (r = 0.40, p = 0.001) was a significant predictor. This study has demonstrated the construct validity and test-retest reliability of the RTSB in a sample of adolescents. The RTSB can reliably rank participants in regards to their resistance training competency and has the necessary sensitivity to detect small changes in resistance training skill proficiency. © 2014 National Strength and Conditioning Association.

Objective Theory-based interventions to promote physical activity (PA) are more effective than atheoretical approaches; however, the comparative utility of theoretical models is rarely tested in longitudinal designs with multiple time points. Further, there is limited research that has simultaneously tested social-cognitive models with self-report and objective PA measures. The primary aim of this study was to test the predictive ability of three theoretical models (social cognitive theory, theory of planned behaviour, and protection motivation theory) in explaining PA behaviour. Methods Participants were adults with type 2 diabetes (n = 287, 53.8% males, mean age = 61.6 ± 11.8 years). Theoretical constructs across the three theories were tested to prospectively predict PA behaviour (objective and self-report) across three 6-month time intervals (baseline-6, 6-12, 12-18 months) using structural equation modelling. PA outcomes were steps/3 days (objective) and minutes of MET-weighted PA/week (self-report). Results The mean proportion of variance in PA explained by these models was 6.5% for objective PA and 8.8% for self-report PA. Direct pathways to PA outcomes were stronger for self-report compared with objective PA. Conclusions These theories explained a small proportion of the variance in longitudinal PA studies. Theory development to guide interventions for increasing and maintaining PA in adults with type 2 diabetes requires further research with objective measures. Theory integration across social-cognitive models and the inclusion of ecological levels are recommended to further explain PA behaviour change in this population. Statement of contribution What is already known on this subject? Social-cognitive theories are able to explain partial variance for physical activity (PA) behaviour. What does this study add? The testing of three theories in a longitudinal design over 3, 6-month time intervals. The parallel use and comparison of both objective and self-report PA measures in testing these theories. © 2013 The British Psychological Society.

Objective: To evaluate the impact of a 12-month school-based multi-component program on adolescent girls' physical activity and sedentary behaviors, and hypothesized mediators of physical activity behavior change. Design: Group randomized controlled trial with 12-month follow-up. Methods: The intervention, guided by Social Cognitive Theory, involved 357 adolescent girls (13.2. ±. 0.5 years) from 12 secondary schools (6 intervention schools, 6 control schools) in low-income communities in the Hunter and Central Coast regions of New South Wales, Australia.The intervention included enhanced school sport, lunchtime physical activity sessions, interactive seminars, student handbooks, nutrition workshops, pedometers, parent newsletters and text messages to encourage physical activity and healthy eating, and a decrease in sedentary behavior. Outcomes were assessed at baseline and 12-months and included: physical activity (accelerometers), sedentary behaviors (questionnaire and accelerometers), and social-cognitive mediators of physical activity (questionnaire). Results: There were significant between group differences in favor of the intervention group for self-reported recreational computer use (-26.0. min; 95% CI, -46.9 to -5.1), and sedentary activities summed (-56.4. min; 95% CI, -110.1 to -2.7), however objective sedentary behavior showed no differences. There were no group-by-time effects for any of the physical activity outcomes or hypothesized mediators. Conclusions: A school-based intervention tailored for adolescent girls from schools located in low-income communities significantly reduced time spent in sedentary activities. However, improvements in physical activity and hypothesized mediators of physical activity behavior were not observed. Future studies are encouraged to explore alternative mechanisms of behavior change derived from integrated and socio-ecological theories. © 2013 Sports Medicine Australia.

Aim: Overweight and obesity prevalence is high among adolescent girls of low socioeconomic position and this increases their risk of cardiovascular disease and metabolic disorders in adulthood. The aim of this present study was to describe the dietary patterns of adolescent girls in terms of the relative contribution of core food groups to overall diet and by weight status category. Methods: Year 8 female students were recruited from schools in low-income communities. Weight status (i.e. underweight, healthy weight, overweight, obese) was determined using age- and sex-adjusted body mass index (BMI; z score). Dietary intakes were assessed using a validated semi-quantitative food frequency questionnaire. Individual foods were collated into core food group or energy-dense, nutrient-poor categories in line with the Australian Guide to Healthy Eating (AGHE) and the percentage contribution to total energy intake calculated. Results: Participants (n = 332) were (mean ± SD) 13.7 ± 0.4 years old with BMI z score 0.63 ± 1.22. Few girls met AGHE core food group recommendations for daily serves; meat and substitutes 69.3%, vegetables 28.6%, fruit 23.8%, dairy 15.7% and breads/cereals 5.7%. Total percentage energy derived from energy-dense, nutrient-poor foods was 46.6% (37.2-54.6%) (median (interquartile range)), with takeaways 9.8% (7.0-13.6%), confectionery 7.0% (4.1-10.9%) and packaged snacks 6.8% (4.0-10.7%), with no significant differences by weight status. Conclusions: Core food intakes are poor with excessive consumption of energy-dense, nutrient-poor foods in these adolescent girls. Nutrition education programs targeting this population are needed to address this imbalance. Strategies could include substitution of unhealthy snacks for core food items and greater inclusion of core foods within main meals. © 2013 Dietitians Association of Australia.

Introduction: The negative consequences of unhealthy weight gain and the high likelihood of pediatric obesity tracking into adulthood highlight the importance of targeting youth who are 'at risk' of obesity. The aim of this paper is to report the rationale and study protocol for the 'Active Teen Leaders Avoiding Screen-time' (ATLAS) obesity prevention intervention for adolescent boys living in low-income communities. Methods/design: The ATLAS intervention will be evaluated using a cluster randomized controlled trial in 14 secondary schools in the state of New South Wales (NSW), Australia (2012 to 2014). ATLAS is an 8-month multi-component, school-based program informed by self-determination theory and social cognitive theory. The intervention consists of teacher professional development, enhanced school-sport sessions, researcher-led seminars, lunch-time physical activity mentoring sessions, pedometers for self-monitoring, provision of equipment to schools, parental newsletters, and a smartphone application and website. Assessments were conducted at baseline and will be completed again at 9- and 18-months from baseline. Primary outcomes are body mass index (BMI) and waist circumference. Secondary outcomes include BMI z-scores, body fat (bioelectrical impedance analysis), physical activity (accelerometers), muscular fitness (grip strength and push-ups), screen-time, sugar-sweetened beverage consumption, resistance training skill competency, daytime sleepiness, subjective well-being, physical self-perception, pathological video gaming, and aggression. Hypothesized mediators of behavior change will also be explored. Discussion: ATLAS is an innovative school-based intervention designed to improve the health behaviors and related outcomes of adolescent males in low-income communities. © 2013 Elsevier Inc.

OBJECTIVE: The goal of this study was to evaluate the impact of the Active Teen Leaders Avoiding Screen-time (ATLAS) intervention for adolescent boys, an obesity prevention intervention using smartphone technology.METHODS: ATLAS was a cluster randomized controlled trial conducted in 14 secondary schools in low-income communities in New South Wales, Australia. Participants were 361 adolescent boys (aged 12-14 years) considered at risk of obesity. The 20-week intervention was guided by self-determination theory and social cognitive theory and involved: teacher professional development, provision of fitness equipment to schools, face-to-face physical activity sessions, lunchtime student mentoring sessions, researcher-led seminars, a smartphone application and Web site, and parental strategies for reducing screen-time. Outcome measures included BMI and waist circumference, percent body fat, physical activity (accelerometers), screen-time, sugar-sweetened beverage intake, muscular fitness, and resistance training skill competency.RESULTS: Overall, there were no significant intervention effects for BMI, waist circumference, percent body fat, or physical activity. Significant intervention effects were found for screen-time (mean ± SE:-30 ± 10.08 min/d; P = .03), sugar-sweetened beverage consumption (mean:-0.6 ± 0.26 glass/d; P = .01), muscular fitness (mean: 0.9 ± 0.49 repetition; P = .04), and resistance training skills (mean: 5.7 6 0.67 units; P < .001).CONCLUSIONS: This school-based intervention targeting low-income adolescent boys did not result in significant effects on body composition, perhaps due to an insufficient activity dose. However, the intervention was successful in improving muscular fitness, movement skills, and key weight-related behaviors.

© 2013 Asian Oceanian Association for the Study of Obesity. Pediatric obesity continues to be a major public health concern. Once established it is difficult to treat, therefore well-designed and evaluated prevention interventions are vitally important. Schools have an important role in the prevention of childhood obesity, however, their involvement can be limited by a number of constraints and barriers, which need to be considered when designing interventions. Members of the Prevention Stream of the Australasian Child and Adolescent Obesity Research Network have extensive experience in implementing and evaluating school-based obesity prevention initiatives. Based on their collective experience and evidence from implementation research, the aim of this paper was to highlight six areas to consider when designing, implementing and evaluating obesity prevention initiatives in schools. Further, this paper aimed to provide guidance for overcoming some of the challenges and barriers faced in school-based obesity prevention research. The six key areas discussed include: design and analysis; school-community engagement; planning and recruitment; evaluation; implementation; and feedback and sustainability.

© 2014 Human Kinetics, Inc. Background: According to social-cognitive theory (SCT), self-efficacy affects health behavior both directly and indirectly by influencing how individuals perceive their environment. This study examines whether perceptions of home and school environment mediate the association between self-efficacy and physical activity (PA) and sedentary behavior in adolescent girls. Methods: Baseline data from the Nutrition and Enjoyable Activity for Teen Girls (NEAT) was used for this study. Grade 8 female students (n = 357) were recruited from 12 secondary schools located in low-income communities in the Hunter Region, New South Wales, Australia. PA was assessed using accelerometers, and sedentary behavior by self-report and accelerometers. Self-reported measures were used for perceived home and school environment and self-efficacy. Multilevel regression models were calculated to determine if the perceived environment mediated the relationship between self-efficacy with both PA and sedentary behavior. Results: The perceptions of the school and home environment did not mediate the relationship between PA self-efficacy and PA behavior or sedentary behavior. Conclusion: The mediated models were not supported for PA or sedentary behavior. However, other results of this paper may be helpful for future theory development and practice. More research is needed to understand behaviors in unique populations such as this.

BACKGROUND: Physical fitness during childhood and adolescence has been identified as an important determinant of current and future health status. While research has traditionally focused on the association between cardio-respiratory fitness and health outcomes, the association between muscular fitness (MF) and health status has recently received increased attention. OBJECTIVE: The aim of this systematic review and meta-analysis was to evaluate the potential physiological and psychological benefits associated with MF among children and adolescents. METHODS: A systematic search of six electronic databases (PubMed, SPORTDiscus, Scopus, EMBASE, PsycINFO and OVID MEDLINE) was performed on the 20th May, 2013. Cross-sectional, longitudinal and experimental studies that quantitatively examined the association between MF and potential health benefits among children and adolescents were included. The search yielded 110 eligible studies, encompassing six health outcomes (i.e., adiposity, bone health, cardiovascular disease [CVD] and metabolic risk factors, musculoskeletal pain, psychological health and cognitive ability). The percentage of studies reporting statistically significant associations between MF and the outcome of interest was used to determine the strength of the evidence for an association and additional coding was conducted to account for risk of bias. Meta-analyses were also performed to determine the pooled effect size if there were at least three studies providing standardised coefficients. RESULTS: Strong evidence was found for an inverse association between MF and total and central adiposity, and CVD and metabolic risk factors. The pooled effect size for the relationship between MF and adiposity was r = -0.25 (95% CI -0.41 to -0.08). Strong evidence was also found for a positive association between MF and bone health and self-esteem. The pooled effect size for the relationship between MF and perceived sports competence was r = 0.39 (95% CI 0.34-0.45). The evidence for an association between MF and musculoskeletal pain and cognitive ability was inconsistent/uncertain. Where evidence of an association was found, the associations were generally low to moderate. CONCLUSION: The findings of this review highlight the importance of developing MF in youth for a number of health-related benefits.

Background: Although previous studies have demonstrated that children with high levels of fundamental movement skill competency are more active throughout the day, little is known regarding children's fundamental movement skill competency and their physical activity during key time periods of the school day (i.e., lunchtime, recess and after-school). The purpose of this study was to examine the associations between fundamental movement skill competency and objectively measured moderate-to-vigorous physical activity (MVPA) throughout the school day among children attending primary schools in low-income communities.Methods: Eight primary schools from low-income communities and 460 children (8.5 ± 0.6 years, 54% girls) were involved in the study. Children's fundamental movement skill competency (TGMD-2; 6 locomotor and 6 object-control skills), objectively measured physical activity (ActiGraph GT3X and GT3X + accelerometers), height, weight and demographics were assessed. Multilevel linear mixed models were used to assess the cross-sectional associations between fundamental movement skills and MVPA.Results: After adjusting for age, sex, BMI and socio-economic status, locomotor skill competency was positively associated with total (P = 0.002, r = 0.15) and after-school (P = 0.014, r = 0.13) MVPA. Object-control skill competency was positively associated with total (P < 0.001, r = 0.20), lunchtime (P = 0.03, r = 0.10), recess (P = 0.006, r = 0.11) and after-school (P = 0.022, r = 0.13) MVPA.Conclusions: Object-control skill competency appears to be a better predictor of children's MVPA during school-based physical activity opportunities than locomotor skill competency. Improving fundamental movement skill competency, particularly object-control skills, may contribute to increased levels of children's MVPA throughout the day.Trial registration: Australian New Zealand Clinical Trials Registry No: ACTRN12611001080910. © 2014 Cohen et al.; licensee BioMed Central Ltd.

Objective: To evaluate the impact of a multi-component school-based physical activity intervention (Fit-4-Fun) on health-related fitness and objectively measured physical activity in primary school children. Methods: Four Hunter primary schools were recruited in April, 2011 and randomized by school into treatment or control conditions. Participants included 213 children (mean age=10.72years±0.6; 52.2% female) with the treatment group (n=118) completing the 8-week Fit-4-Fun Program. Participants were assessed at baseline and 6-month follow-up, with a 91% retention rate. Cardio-respiratory fitness (CRF) (20m shuttle run) was the primary outcome, and secondary outcomes included body composition (BMI, BMIZ), muscular fitness (7-stage sit-up test, push-up test, basketball throw test, Standing Jump), flexibility (sit and reach) and physical activity (7days pedometry). Results: After 6-months, significant treatment effects were found for CRF (adjusted mean difference, 1.14 levels, p<0.001), body composition (BMI mean, -0.96kg/m2, p<0.001 and BMI z-score mean -0.47 z-scores, p<0.001), flexibility (sit and reach mean, 1.52cm, p=0.0013), muscular fitness (sit-ups) (mean 0.62 stages, p=0.003) and physical activity (mean, 3253 steps/day, p<0.001). There were no group by time effects for the other muscular fitness measures. Conclusions: A primary school-based intervention focusing on fitness education significantly improved health-related fitness and physical activity levels in children. © 2012 Elsevier Inc.

Background Obesity prevention among youth of low SES is a public health priority given the higher prevalence of youth obesity in this population subgroup. Purpose To evaluate the 24-month impact of a school-based obesity prevention program among adolescent girls living in low-income communities. Design The study was a school-based group RCT, the Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention. Setting/participants The study involved 12 secondary schools located in low-income communities in New South Wales, Australia. Participants were 357 adolescent girls (aged 13.2±0.5 years). Intervention The 12-month multicomponent intervention was guided by social cognitive theory and involved strategies to promote physical activity, reduce sedentary behaviors, and improve dietary outcomes. Main outcome measures The primary outcome was BMI, and secondary outcomes were BMI z-score; percentage body fat (bioelectrical impedance analysis); physical activity (accelerometers); dietary intake; and recreational screen-time (self-report). Data were collected in 2010-2012 and analyzed in 2012. Results After 24 months, there were no intervention effects on BMI (adjusted mean difference -0.33, 95% CI= -0.97, 0.28, p=0.353) and BMI z-score (-0.12, 95% CI= -0.27, 0.04, p=0.178). However, there was a group-by-time interaction for percentage body fat (-1.96%, 95% CI= -3.02, -0.89, p=0.006). Intervention effects for physical activity, screen time, and dietary intake were not significant. Conclusions The NEAT Girls intervention did not result in effects on the primary outcome. Further study of youth who are "at risk" of obesity should focus on strategies to improve retention and adherence in prevention programs. Trial registration This study is registered at Australian New Zealand Clinical Trials ACTRN1261000033004. © 2013 American Journal of Preventive Medicine.

Objective: To provide a user's guide for selecting an appropriate method to assess sedentary behaviours among children and adolescents. Design: While recommendations regarding specific instruments are not provided, the guide offers information about key attributes and considerations for objective (accelerometry; inclinometers; direct observation; screen monitoring devices) and subjective (self-report; parent report; and time use diaries/logs) approaches to assess sedentary behaviour Attributes of instruments and other factors to be considered in the selection of assessment instruments include: population (age); sample size; respondent burden; method/delivery mode; assessment time frame; physical activity information required (data output); data management; measurement error; cost (instrument and administration) and other limitations. Methods: Expert consensus among members of the Australasian Child and Adolescent Obesity Research Network's (ACAORN) Physical Activity and Sedentary Behaviour Special Interest Group. Results: We developed decision flow charts to assist researchers and practitioners select an appropriate method of assessing sedentary behaviour, identified attributes of each method and described five real-life scenarios to illustrate considerations associated with the selection of each method of measurement. Conclusions: It is important that researchers, practitioners and policy makers understand the strengths and limitations of different methods of assessing sedentary behaviour among youth, and are guided on selection of the most appropriate instrument/s to suit their needs. © 2012 .

Background: This study aimed to develop and evaluate the construct validity and reliability of modernized social cognitive measures relating to physical activity behaviors in adolescents. Methods: An instrument was developed based on constructs from Bandura's Social Cognitive Theory and included the following scales: self-efficacy, situation (perceived physical environment), social support, behavioral strategies, and outcome expectations and expectancies. The questionnaire was administered in a sample of 171 adolescents (age = 13.6 ± 1.2 years, females = 61%). Confirmatory factor analysis was employed to examine model-fit for each scale using multiple indices, including chi-square index, comparative-fit index (CFI), goodness-of-fit index (GFI), and the root mean square error of approximation (RMSEA). Reliability properties were also examined (ICC and Cronbach's alpha). Results: Each scale represented a statistically sound measure: fit indices indicated each model to be an adequate-to-exact fit to the data; internal consistency was acceptable to good (a = 0.63-0.79); rank order repeatability was strong (ICC = 0.82-0.91). Conclusions: Results support the validity and reliability of social cognitive scales relating to physical activity among adolescents. As such, the developed scales have utility for the identification of potential social cognitive correlates of youth physical activity, mediators of physical activity behavior changes and the testing of theoretical models based on Social Cognitive Theory. © 2013 Human Kinetics, Inc..

Background: Excessive time spent in sedentary behavior is associated with a range of physiological, psychosocial and behavioral health concerns in youth. Objective: The primary aim of this study was to examine the association between sedentary behavior and self-esteem among adolescent girls living in low-income communities. Methods: Participants were 357 girls [mean age (standard deviation) = 13.2 (0.5) years] from 12 secondary schools located in low-income communities in New South Wales, Australia. Height, weight, body fat (bio-electrical impedance analysis) and physical activity (accelerometers), self-esteem were assessed. Results: Significant inverse associations were found between self-esteem and time spent watching DVDs and using the computer for non-school purposes, but no relationship was found between TV viewing and self-esteem. The relationship between sedentary time (%) from accelerometers and self-esteem was not significant. Conclusions: Sedentary behavior is a pervasive public health concern and time spent in specific screen-based recreation was associated with self-esteem in adolescent girls living in low-income communities. Our findings are indicative of the complex nature of these relationships and reveal a need for further longitudinal and intervention-based research in the field. Copyright © 2012 Published by Elsevier Ltd. All rights reserved.