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The aim of this study was to determine the efficacy and feasibility of a resistance-training (RT) and lifestyle-activity program for sedentary older adults. Eligible participants (N = 44) were randomized to an 8-wk intervention or a control group. The primary outcome was lower body muscle strength, and participants completed a range of secondary outcomes. There was a significant group-by-time interaction for lower body muscle strength (difference = 3.9 repetitions [reps], 95% CI = 2.0-5.8 reps; p < .001; d = 1.0). Changes in secondary outcomes were generally small and not statistically significant. Attendance and program satisfaction were both high. A combined elastic-tubing RT and lifestyle-activity program delivered in the community setting is an efficacious and feasible approach to improve health in sedentary older adults.

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 = 10.72 years ± 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) (20 m shuttle run) was the primary outcome, and secondary outcomes included body composition (BMI, BMI(Z)), muscular fitness (7-stage sit-up test, push-up test, basketball throw test, Standing Jump), flexibility (sit and reach) and physical activity (7 days 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, -0.96 kg/m(2), p < 0.001 and BMI z-score mean -0.47 z-scores, p < 0.001), flexibility (sit and reach mean, 1.52 cm, 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., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objectives: The purpose of this study was to explore potential moderators and mediators of intervention effects in the Physical Activity Leaders (PALs) obesity prevention program for adolescent boys from disadvantaged secondary schools., Design: Group randomized controlled trial., Methods: One hundred adolescent boys (mean age=14.3 (0.6) years) from four schools were randomized to the PALs intervention or a control group for the 6-month study period. The primary outcome was change in BMI and secondary outcomes were physical activity assessed using pedometers and constructs from Social Cognitive Theory (SCT) assessed using a questionnaire., Results: Moderation analyses revealed a significant weight status interaction for BMI (p=0.04), indicating stronger intervention effects for youth classified as overweight/obese at baseline. The intervention had a significant effect on resistance training self-efficacy (p<0.001), but none of the SCT constructs satisfied the criteria for mediation. The number of intervention sessions attended was associated with changes in BMI (r=-0.38, p=0.001), resistance training self-efficacy (r=0.42, p<0.001) and physical activity behavioral strategies (r=0.26, p=0.018). Changes in BMI were also associated with changes in resistance training self-efficacy (r=-0.21, p=0.06) and physical activity behavioral strategies (r=-0.29, p=0.009)., Conclusions: A school-based intervention incorporating student leadership increased adolescent boys' resistance training self-efficacy, but changes in physical activity were not detected and none of the SCT constructs satisfied the criteria for mediation. Baseline weight status was a moderator of intervention effect with the strongest intervention effects observed among overweight and obese adolescent boys., (Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Objectives: Resistance training in untrained adolescents can positively effect health-related fitness as well as improve muscular power and sports performance. The impact of resistance training on adolescent athletes is less clear. The purpose of this review is to determine the effectiveness of resistance training programs on muscular power and sports performance in adolescent athletes., Design: Systematic review and meta-analysis of previously published studies investigating resistance training in adolescent athlete populations., Methods: A systematic search of Medline, Embase, and SPORTDiscus databases was conducted on 21st March 2011 to identify studies evaluating resistance training programs on power and sports performance in adolescent athletes., Results: Thirty-four studies were identified. All but two of the studies reported at least one statistically significant improvement in an alactic muscular power outcome. The most common indicators of alactic power were vertical jump (25 studies) and sprint running (13 studies) performance. Fourteen studies provided data to allow for pooling of results in a meta-analysis. A positive effect was detected for resistance training programs on vertical jump performance (mean difference 3.08 [95% CI 1.65, 4.51], Z=4.23 [P<0.0001])., Conclusions: There is sufficient evidence to conclude that resistance-training interventions can improve muscular power in adolescent athletes. A positive effect on sports performance attributable to participation in resistance training was reported by almost half the included studies, however limited objective evidence to support these claims was found. Improvements in motor performance skills, such as jumping, are widely stated as indicators of improvements in sporting performance., (Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Background: The physical activity (PA) levels of many children and adolescents in Australia are currently insufficient to promote health benefits. Physical education (PE) programs aim to promote PA and reach nearly all school-aged children, but PA levels within PE lessons are often low. PE teachers may influence children's motivation to be physically active in PE lessons, but little is known about teacher strategies that effectively motivate children to participate in PA, and few intervention studies have examined motivational strategies in PE. The purpose of this study was to compare the effect of three motivational strategies, each based on Self-Determination Theory (SDT), on PA levels, and their hypothesized antecedents, during year 8 PE lessons., Methods/design: This study employed a cluster-randomized controlled trial design. Following a familiarization session, PA levels and hypothesized PA antecedents were measured during a baseline lesson and a post-intervention or control lesson. Teachers (n = 16) and their classes from five secondary schools in Sydney, Australia were randomly assigned into four blocks and instructed to provide one of four 20-min lesson teaching strategy conditions: (1) explaining the relevance of activities; (2) providing choice from PA options selected by the teacher; (3) providing equipment and free choice of activities; or (4) usual practice. The primary outcomes were lesson time spent in moderate-to-vigorous PA, and motivation towards the lesson. Secondary outcomes were perceptions of teacher behavior, psychological needs satisfaction, and lesson time spent in sedentary behavior. PA and sedentary behavior were measured during baseline and post-intervention lessons with waist-mounted Actigraph GT3X accelerometers. Teacher behavior, psychological needs satisfaction, and motivation were assessed via questionnaires at the end of each lesson. Linear mixed-model analyses will be run on all outcomes, with students nested within teachers as a random effect., Discussion: Study findings will inform the development of effective SDT-based teaching strategy interventions to enhance students' psychological needs satisfaction, motivation, and PA levels. More effective teaching strategies may be identified that are capable of improving adolescents' PA levels, and thereby provide beneficial population health outcomes., Trial Registration: This trial is registered with Current Controlled Trials and is traceable as ISRCTN07038258.

OBJECTIVE To evaluate the impact of a 12-month multicomponent school-based obesity prevention program, Nutrition and Enjoyable Activity for Teen Girls among adolescent girls. DESIGN Group randomized controlled trial with 12-month follow-up. SETTING Twelve secondary schools in low-income communities in the Hunter and Central Coast regions of New South Wales, Australia. PARTICIPANTS Three hundred fifty-seven adolescent girls aged 12 to 14 years. INTERVENTION A multicomponent school-based intervention program tailored for adolescent girls. The intervention was based on social cognitive theory and included teacher professional development, enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity sessions, handbooks and pedometers for self-monitoring, parent newsletters, and text messaging for social support. MAIN OUTCOME MEASURES Body mass index (BMI, calculated as weight in kilograms divided by height in meters squared), BMI z score, body fat percentage, physical activity, screen time, dietary intake, and self-esteem. RESULTS After 12 months, changes in BMI (adjusted mean difference, -0.19; 95% CI, -0.70 to 0.33), BMI z score (mean, -0.08; 95% CI, -0.20 to 0.04), and body fat percentage (mean, -1.09; 95% CI, -2.88 to 0.70) were in favor of the intervention, but they were not statistically different from those in the control group. Changes in screen time were statistically significant (mean, -30.67 min/d; 95% CI, -62.43 to -1.06), but there were no group by time effects for physical activity, dietary behavior, or self-esteem. CONCLUSIONS A school-based intervention tailored for adolescent girls from schools located in low-income communities did not significantly reduce BMI gain. However, changes in body composition were of a magnitude similar to previous studies and may be associated with clinically important health outcomes. TRIAL REGISTRATION anzctr.org.au Identifier: 12610000330044.

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

Objectives: To evaluate the effect of a school-based obesity prevention programme on physical self-perception and key physical-activity related cognitions in adolescent boys from disadvantaged secondary schools. A secondary objective was to determine if any psychological changes were associated with improved weight status., Methods: Participants (n = 100, age = 14.3[0.6]) were randomized to the PALS (Physical Activity Leaders) intervention (n = 50) or a control group (n = 50) and assessed at baseline, 3- and 6-month follow up. Measures included BMI, BMI z-score and % body fat (bioelectrical impedance analysis). Students also completed the Children's Physical Self-Perception Profile and a physical activity-related cognitions questionnaire. The findings include secondary data analyses., Results: Relative to the controls, the PALS group significantly increased their physical self worth (p = .01), perceived physical condition (p = .02), resistance training self efficacy (p < .001) and their use of physical activity behavioural strategies (p = .02)., Conclusions: A school-based obesity prevention programme that targeted leadership skills improved psychological health in the physical domain in adolescent boys from disadvantaged schools., (© 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.)

Background: A poor understanding of the specific lifestyle behaviors that result in weight loss has hindered the development of effective interventions. The aim of this paper was to identify potential behavioral mediators of weight loss in the Healthy Dads, Healthy Kids (HDHK) intervention for overweight fathers., Findings: The three-month intervention was evaluated in a randomized controlled trial and conducted in Newcastle, New South Wales, Australia. Baseline, three month (immediate post-intervention) and six month assessments were conducted. Recruitment and follow-up occurred between October 2008 and May 2009. The study sample included 53 overweight/obese men [mean ( SD) age=40.6( 97.1) years; body mass index (BMI)=33.2 (3.9) kgm-2] and their primary school-aged children [n=71, 54% boys; age=8.2 (2.0) years] who were randomized to HDHK program or a wait-list control group. Physical activity (PA) was assessed using pedometers and dietary behaviors were measured using a validated food frequency questionnaire. The intervention resulted in significant weight loss (5.131.27 kg, P<0.0001) and increased PA among fathers (2769750 steps/day, P<0.001) and their children (1486521 steps/day, P<0.01). Fathers PA mediated weight loss in the intervention (AB=2.31, 95% CI=4.63 to 0.67) and was responsible for 47% of the intervention effect. Changes in dietary behaviors were not statistically significant., Conclusions: PA was an important mediator of weight loss in the HDHK intervention. Encouraging overweight fathers to be more active with their children appears to be a promising strategy for obesity treatment in men.

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

The aim of this study was to examine gender differences in the impact of a school garden and nutrition curriculum on fruit and vegetable intake, willingness to taste, and taste ratings in 127 children (11 to 12 years, 54% boys) in regional New South Wales, Australia. Classes were assigned to wait-list control, nutrition education only (NE), or nutrition education plus garden (NE + G) groups. Carrot taste rating was the only vegetable for which there was a significant gender difference, with girls rating it more highly (p = .04). There were no significant gender differences in fruit and vegetable consumption or willingness to taste scores for any other vegetables. There was a group effect (p < .001) for overall willingness to taste, overall taste rating, and the taste rating of pea and broccoli (p < .001), tomato (p = .03), and lettuce (p = .02). In the post hoc analysis by gender, both boys and girls in NE + G and NE groups were more willing to taste vegetables compared with control boys and girls postintervention (p < .001, p = .02). Boys in the NE + G group were more willing to taste all vegetables overall compared with NE boys at posttest (p = .05) and this approached significance for girls (p = .07). For overall tasting scores, a group effect was seen in girls only (p = .05). No significant treatment-time effect was found for vegetable intake in either gender. Further research is needed to examine whether a school garden, with or without school curriculum components, can be used to optimize fruit and vegetable intakes, particularly in boys.

Much of the research on the determinants of dietary behavior has been guided by Bandura's Social Cognitive Theory (SCT), yet few studies have tested the utility of its proposed structural paths. The aim of this paper was to test the capacity of SCT to explain dietary behaviors in a sample of 357 adolescent girls (13.2±0.5 years) from 12 secondary schools located in low-income communities in New South Wales, Australia. Participants completed validated SCT scales assessing nutrition-related self-efficacy, intention, behavioral strategies, family support, situation, outcome expectations, and outcome expectancies. Participants completed a validated food frequency questionnaire, from which, the percentage of total kilojoules from core-foods, non-core foods and saturated fat were calculated. The theoretical models were tested using structural equation modeling in AMOS. The models explained 48-51% and 13-19% of the variance in intention and dietary behavior, respectively. The models provided an adequate fit to the data, and self-efficacy was positively associated with healthy eating and inversely associated with unhealthy eating. However, the pathway from intention to behavior was not statistically significant in any of the models. While this study has demonstrated the utility of SCT constructs to explain behavior in adolescents girls, the proposed structural pathways were not supported. Further study of the role that implementation intentions play in explaining adolescent girls' dietary behaviors is required., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background:   Physical activity programmes have been identified as a potential strategy for improving social and emotional well-being in at-risk youth, who have a prevalence of depression and low self-esteem exceeding the general population., Methods:   A systematic search of six electronic databases (EMBASE, OVID MEDLINE, PsychINFO, PubMed, Scopus and SPORTDiscus) was conducted to identify physical activity programmes designed to improve social and emotional well-being in at-risk youth., Results:   The search identified 15 studies, which reported the effects of three types of physical activity programmes (i.e. outdoor adventure, sport and skill-based and physical fitness programmes) on social and emotional well-being. While many of the interventions resulted in significant positive effects, the risk of bias was high in all of the included studies., Conclusion:   Due to the mixed findings and the high risk of bias, it is difficult to determine the efficacy of physical activity programmes for improving social and emotional well being in at-risk youth., (© 2011 The Authors. Child and Adolescent Mental Health © 2011 Association for Child and Adolescent Mental Health.)

The aim of this paper was to describe and test a social cognitive model of physical activity tailored for adolescent girls. Participants were 1518 girls (aged 13.6 ± 0.02 years) from 24 secondary schools in New South Wales, Australia. Useable accelerometer (≥10 hours day(-1) on at least 3 days) and questionnaire data were obtained from 68% of this sample (N = 1035). Participants completed questionnaires assessing psychological, behavioural, social and environmental correlates of activity. The theoretical model was tested using structural equation modelling in AMOS. The model explaining accelerometer counts per minute was an adequate-to-good fit to the data (Tucker-Lewis Index = 0.89, the comparative fit index = 0.97 and the root mean square of approximation = 0.098; 90% confidence interval = 0.075-0.122) but explained only 5% of the variance in activity. There were significant model pathways from self-efficacy (r = 0.11, P = 0.01), school environment (r = 0.07, P = 0.02) and physical self-worth (r = 0.07, P = 0.04) to accelerometer counts. Although the proposed model provided an adequate-to-good fit to the data, it explained a small portion of the variance. Shared method variance may explain the larger portions of variance explained in previous studies. Future studies are encouraged to evaluate theories of physical activity behaviour change using objective measures of physical activity.

A poor understanding of behaviour change mechanisms has hindered the development of effective physical activity interventions. The aim of this study was to identify potential mediators of change in a home-based resistance training (RT) program for obese individuals with type 2 diabetes. Obese individuals with type 2 diabetes (N = 48) were randomly allocated to either an RT intervention (n = 27) or a control group (n = 21) for the 16-week study period. The study sample included 16 men and 32 women and the mean age of participants was 54.4 (±11.7) years. Participants in the RT group received a multi-gym and dumbbells and home supervision from a certified personal trainer. RT behaviour was measured using a modified Godin Leisure Time Questionnaire. Social-cognitive constructs were measured and tested in a mediating variable framework using a product-of-coefficients test. The intervention had a significant effect on RT behaviour (p < 0.001) and muscular strength (p < 0.001). The intervention had a significant effect on RT planning strategies (p < 0.01), which mediated the effect of the intervention on RT behaviour. The home-based RT program successfully targeted participants' RT planning strategies which contributed to their exercise adherence.

Background: The Behavioral Regulation in Exercise Questionnaire (BREQ) and the BREQ-2 are the most commonly used measures of behavioural regulation in exercise psychology. The purpose of the study was to assess the validity and reliability of the Iranian version of the BREQ-2 on a sample of university students., Methods: The BREQ-2 was translated into Persian by qualified experts and the psychometric properties of the instrument were assessed. Content validity was established, using a panel of 12 Iranian experts in the areas of health education, psychology, and exercise. Construct validity was assessed via confirmatory factor analysis (CFA), using LISREL 8.80 (N = 418). The reliability of the BREQ-2 was assessed, using a 2-week test-retest to establish its stability and Cronbach's Alpha to estimate its internal consistency., Results: The Iranian version of the BREQ-2 was slightly modified to improve content validity. Primary results of confirmatory factor analysis did not fully support the 5-factor uncorrelated model. The model was modified; and the fit indices indicated that the 5-factor correlated model was the best fit. The scale was found to have acceptable internal consistency (α > 0.7) and test-retest reliability (intra-class correlation coefficient [ICC] > 0.80)., Conclusion: The Iranian BREQ-2 has acceptable validity and reliability in the study sample and may be used in relevant studies to assess behavioural regulation in similar samples.

Background: Declining levels of physical fitness in children are linked to an increased risk of developing poor physical and mental health. Physical activity programs for children that involve regular high intensity physical activity, along with muscle and bone strengthening activities, have been identified by the World Health Organisation as a key strategy to reduce the escalating burden of ill health caused by non-communicable diseases. This paper reports the rationale and methods for a school-based intervention designed to improve physical fitness and physical activity levels of Grades 5 and 6 primary school children., Methods/design: Fit-4-Fun is an 8-week multi-component school-based health-related fitness education intervention and will be evaluated using a group randomized controlled trial. Primary schools from the Hunter Region in NSW, Australia, will be invited to participate in the program in 2011 with a target sample size of 128 primary schools children (age 10-13). The Fit-4-Fun program is theoretically grounded and will be implemented applying the Health Promoting Schools framework. Students will participate in weekly curriculum-based health and physical education lessons, daily break-time physical activities during recess and lunch, and will complete an 8-week (3 × per week) home activity program with their parents and/or family members. A battery of six health-related fitness assessments, four days of pedometery-assessed physical activity and a questionnaire, will be administered at baseline, immediate post-intervention (2-months) and at 6-months (from baseline) to determine intervention effects. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention program, assessments, process evaluation and statistical analyses are described., Discussion: The Fit-4-Fun program is an innovative school-based intervention targeting fitness improvements in primary school children. The program will involve a range of evidence-based behaviour change strategies to promote and support physical activity of adequate intensity, duration and type, needed to improve health-related fitness., Trial Registration No: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000976987.

Background: The 'Healthy Dads, Healthy Kids' program was designed to help overweight fathers lose weight and positively influence the health behaviors of their children. The aim of the current study was to evaluate the previously established program in a community setting, in a large effectiveness trial., Methods/design: The Healthy Dads, Healthy Kids community trial consists of three stages: (i) Stage 1 - program refinement and resource development (ii) Stage 2 - community randomized controlled trial (iii) Stage 3 - community effectiveness trial. The program will be evaluated in five Local Government Areas in the Hunter Valley Region of NSW, Australia. For the community randomized controlled trial, 50 overweight/obese men (aged 18-65 years) from one Local Government Area with a child aged between 5-12 years of age will be recruited. Families will be randomized to either the program or a 6-month wait-list control group. Fathers and their children will be assessed at baseline, post-intervention (3-months) and 6-months. Inclusion criteria are: body mass index 25-40 kg/m2; no participation in other weight loss programs during the study; pass a health-screening questionnaire; and access to a computer with Internet facilities. In the community trial, the program will be evaluated using a non-randomized, prospective design in five Local Government Areas. The exclusion criteria is body mass index < 25 kg/m2 or lack of doctor's approval. MEASURES will be collected at baseline, 3-, 6- and 12-months. The program involves fathers attending seven face-to-face group sessions (three with children) over 3-months., Measures: The primary outcome is fathers' weight. Secondary outcomes for both fathers and children include: waist circumference, blood pressure, resting heart rate, physical activity, sedentary behaviors and dietary intake. Father-only measures include portion size, alcohol consumption, parenting for physical activity and nutrition and parental engagement. Process evaluation will determine the fidelity, dose (delivered and received), reach, recruitment and context of the program., Discussion: As a unique approach to reducing obesity prevalence in men and improving lifestyle behaviours in children, our findings will provide important evidence relating to the translation of Healthy Dads, Healthy Kids, which will enable it to be delivered on a larger scale., Trial Registration: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000608066.

Purpose: To test the Theory of Planned Behavior (TPB) in a large population sample of adolescents from Alberta, Canada., Methods: 4,073 adolescents completed a self-administered web-based survey related to physical activity (PA)., Results: TPB explained 59% and 43% of the variance for intention and behavior, respectively. Moderating (by gender) and mediating tests were supported., Conclusions: TPB is useful for understanding PA in this population., (Copyright © 2011 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

The aim of this review was to evaluate the reliability and validity of methods used to assess the multiple components of sedentary behaviour (i.e. screen time, sitting, not moving and existing at low energy expenditure) in children and adolescents. Twenty-six studies met our inclusion criteria and were reviewed. Thirteen studies reported the reliability of self- and proxy-report measures of sedentary behaviour and seven of these were found to have acceptable test-retest reliability. Evidence for the criterion validity of self- and proxy-report measures was examined in three studies with mixed results. Seven studies examined the reliability and/or validity of direct observation and the findings were generally positive. Five studies demonstrated the utility of accelerometers to accurately classify sedentary behaviour. Self-report measures provide reliable estimates of screen time, yet their validity remains largely untested. While accelerometers can accurately classify participants' behaviour as sedentary, they do not provide information about type of sedentary behaviour or context. Studies utilizing measures of sedentary behaviour need to more adequately report on the validity and reliability of the measures used. We recommend the use of objective measures of sedentary behaviour such as accelerometers, in conjunction with subjective measures (e.g. self-report), to assess type and context of behaviour., (© 2011 The Authors. obesity reviews © 2011 International Association for the Study of Obesity.)

Background: Physical activity levels decline markedly among girls during adolescence. School-based interventions that are multi-component in nature, simultaneously targeting curricular, school environment and policy, and community links, are a promising approach for promoting physical activity. This report describes the rationale, design and baseline data from the Girls in Sport group randomised trial, which aims to prevent the decline in moderate-to-vigorous intensity physical activity (MVPA) among adolescent girls., Methods/design: A community-based participatory research approach and action learning framework are used with measurements at baseline and 18-month follow-up. Within each intervention school, a committee develops an action plan aimed at meeting the primary objective (preventing the decline in accelerometer-derived MVPA). Academic partners and the State Department of Education and Training act as critical friends. Control schools continue with their usual school programming. 24 schools were matched then randomized into intervention (n = 12) and control (n = 12) groups. A total of 1518 girls (771 intervention and 747 control) completed baseline assessments (86% response rate). Useable accelerometer data (≥ 10 hrs/day on at least 3 days) were obtained from 79% of this sample (n = 1199). Randomisation resulted in no differences between intervention and control groups on any of the outcomes. The mean age (SE) of the sample was 13.6 (± 0.02) years and they spent less than 5% of their waking hours in MVPA (4.85 ± 0.06)., Discussion: Girls in Sport will test the effectiveness of schools working towards the same goal, but developing individual, targeted interventions that bring about changes in curriculum, school environment and policy, and community links. By using community-based participatory research and an action learning framework in a secondary school setting, it aims to add to the body of literature on effective school-based interventions through promoting and sustaining increased physical activity participation among adolescent girls., Trial Registration Number: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610001077055.

Pediatric overweight and 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. There is considerable evidence to suggest that obesity prevention initiatives can change children's behaviours and weight status over the short- or medium-term; however, there is far less evidence on which to judge the impact over the longer term. In response to the rise in short- and medium-term obesity prevention studies for children and adolescents over recent years, the Prevention Stream of the Australasian Child and Adolescent Obesity Research Network highlight five points as to why the dearth of obesity prevention studies with long-term follow-up should be urgently addressed. Furthermore, recommendations to strengthen the evidence base and outline key implications for research design in this area and the support required for long-term follow-up studies are detailed.

Worldwide, public health physical activity guidelines include special emphasis on populations of children (typically 6-11 years) and adolescents (typically 12-19 years). Existing guidelines are commonly expressed in terms of frequency, time, and intensity of behaviour. However, the simple step output from both accelerometers and pedometers is gaining increased credibility in research and practice as a reasonable approximation of daily ambulatory physical activity volume. Therefore, the purpose of this article is to review existing child and adolescent objectively monitored step-defined physical activity literature to provide researchers, practitioners, and lay people who use accelerometers and pedometers with evidence-based translations of these public health guidelines in terms of steps/day. In terms of normative data (i.e., expected values), the updated international literature indicates that we can expect 1) among children, boys to average 12,000 to 16,000 steps/day and girls to average 10,000 to 13,000 steps/day; and, 2) adolescents to steadily decrease steps/day until approximately 8,000-9,000 steps/day are observed in 18-year olds. Controlled studies of cadence show that continuous MVPA walking produces 3,300-3,500 steps in 30 minutes or 6,600-7,000 steps in 60 minutes in 10-15 year olds. Limited evidence suggests that a total daily physical activity volume of 10,000-14,000 steps/day is associated with 60-100 minutes of MVPA in preschool children (approximately 4-6 years of age). Across studies, 60 minutes of MVPA in primary/elementary school children appears to be achieved, on average, within a total volume of 13,000 to 15,000 steps/day in boys and 11,000 to 12,000 steps/day in girls. For adolescents (both boys and girls), 10,000 to 11,700 may be associated with 60 minutes of MVPA. Translations of time- and intensity-based guidelines may be higher than existing normative data (e.g., in adolescents) and therefore will be more difficult to achieve (but not impossible nor contraindicated). Recommendations are preliminary and further research is needed to confirm and extend values for measured cadences, associated speeds, and MET values in young people; continue to accumulate normative data (expected values) for both steps/day and MVPA across ages and populations; and, conduct longitudinal and intervention studies in children and adolescents required to inform the shape of step-defined physical activity dose-response curves associated with various health parameters.

Parental dietary intake, lifestyle behavior, and parenting style influence a child's weight status. Few studies have examined associations between parent-child dietary intake, or specific father-child associations. This cross-sectional study examined associations between father-child dietary intakes of fruit, vegetables, and selected energy-dense nutrient-poor foods. The study population consisted of overweight fathers with 50 father-child dyads included in the analysis; median (interquartile range) age of fathers was 39±8.0 years; body mass index was 32.7±5.3; and their primary school-aged children (n=50) (54% boys aged 8.5±3.0 years, body mass index z score 0.6±1.6) who had been targeted to participate in the Healthy Dads, Healthy Kids pilot trial in the Hunter region, New South Wales, Australia in 2008. Dietary intakes of fathers and children were assessed using validated food frequency questionnaires, with mothers reporting their child's food intake. Descriptive statistics were reported and Spearman's rank order correlations used to test the strength of associations between father-child intakes. Fathers' median (interquartile range) daily fruit and vegetable intakes were 0.9 (1.5) and 2.2 (1.3) servings/day, respectively, whereas children consumed 2.1 (2.4) fruit and 2.9 (2.1) vegetable servings/day. Moderately-strong positive correlations were found between father-child fruit intakes (r=0.40, P<0.01), cookies (r=0.54, P<0.001), and potato chips (r=0.33, P<0.05). There were no associations between intakes of vegetables, ice cream, chocolate, or french fries (P>0.05). Children's intakes of fruit and some energy-dense nutrient-poor foods but not vegetables were related to their father's intakes. The targeting of fathers should be tested in experimental studies as a potential strategy to improve child and family eating habits., (Copyright © 2011 American Dietetic Association. Published by Elsevier Inc. All rights reserved.)

Summary: Recruiting men to weight loss programs is notoriously difficult and little is known about the experiences of men who participate in weight loss programs. The aims of this paper were to report the perceptions and experiences of men who enrolled in the SHED-IT (Self-Help, Exercise, Diet and Information Technology) randomized controlled trial in the context of (1) what attracted them to the program, (2) their satisfaction with the program and its components, and (3) their suggestions for improvements to the program. The SHED-IT program exclusively targeted men and was developed to appeal to men. Individual semi-structured interviews were conducted with 18 overweight/obese (BMI between 25 and 37 kg/m(2)) men aged 18-60 years who were employed or enrolled at the University of Newcastle and who had been enrolled to the SHED-IT trial and randomly allocated to receive either the Internet intervention or basic weight-loss Information Only. Significant weight loss was achieved by both groups. A thematic analysis was undertaken applying the constant comparison method. Results indicated that lack of knowledge was a major weight loss barrier and men were attracted to a program that did not require extensive time commitments, was tailored for men and allowed inclusion of 'treat' food and drinks. Men were satisfied with both programs and valued the education about energy balance and the humour used to deliver simple messages. More face-to-face contact was a common suggestion for improvement. Our findings will inform future weight loss interventions for men and assist researchers and practitioners to engage men in weight loss.:, (© 2011 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.)

It has been suggested that conditioning programmes have the potential to improve golf performance through fitness adaptations. The primary aim of this systematic review was to evaluate the effectiveness of conditioning programmes on measures of golf-related fitness and golf performance. Four electronic library databases were searched and the quality of the studies was assessed using criteria adapted from the Consolidated Standard of Reporting Trials statement. Thirteen studies satisfied our criteria for inclusion. Nine studies involved middle-aged to older male recreational golfers and four studies used younger more skilled golfers. Conditioning programmes involved the use of machine weights, free weights, medicine balls, and elastic bands, and most studies included a flexibility component. Most studies assessed changes in fitness characteristics and generally resulted in improvements. All but two of the studies assessed changes in club head speed and reported increases. The findings from this review suggest that strength and conditioning programmes can have a positive effect on the golf swing and fitness characteristics of golfers. The majority of studies in this review evaluated the effects of generic conditioning programmes on fitness characteristics and club head speed. Future studies should investigate the effects of more golf-specific strength and conditioning programmes to improve fitness and overall golf performance.

The primary aim of this study was to investigate gender differences in the relationship between muscular strength, body composition, and physical self-perception in adolescents. Participants (n=106, age 15.0±0.7 years, 51% boys) completed the following assessments: height and weight, bio-electrical impedance analysis (body fat %), muscular strength (1RM bench press and leg press), and the Children's Physical Self-Perception Profile. Bivariate correlations were examined and mediation analysis was used to explore if physical self-perception sub-domains mediated the relationship between muscular strength/adiposity and overall physical self-worth. Among boys, physical self-worth was associated with absolute total strength (r=0.36, p<0.01), but not with body fat % (r=-0.11, p=0.44), or relative total strength (r=0.21, p=0.13). In adolescent girls, physical self-worth was associated with body fat % (r=-0.42, p<0.01), relative total strength (r=0.40, p<0.01) but not absolute total strength (r=0.07, p=0.62). In boys, perceived physical strength mediated the relationship between absolute muscular strength and physical self-worth. Relative muscular strength was not associated with perceived strength (p>0.05) in girls and the test of the mediated effect was non-significant (p>0.05). Perceived body attractiveness was found to mediate the relationship between body fat % and physical self-worth among boys and girls. Physical self-worth is associated with different components of health-related fitness in adolescent girls and boys. Mediation analysis can be used to provide insights into the complex interrelationships between variables., (Copyright © 2010 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Purpose: Motor skills are considered a prerequisite to physical activity, yet the relationship may be reciprocal and perceived sports competence might mediate associations., Methods: In 2006/2007, 215 adolescents completed motor skill proficiency (Get Skilled Get Active), perceived sport competence (Physical Self-Perception Profile) and physical activity assessments (Adolescent Physical Activity Recall Questionnaire) as part of the Physical Activity and Skills Study. Using AMOS (Version 7.0), reciprocal relationships were examined between motor skill (object control and locomotor) and moderate to vigorous physical activity (MVPA). Both models were then run in different versions to understand the role of perceived sports competence as a potential mediator., Results: Mean age was 16.4 yr (SD=0.6), 51.6% (111/215) were females. A reciprocal relationship between object control and MVPA and a one-way relationship from MVPA to locomotor skill was found. When perceived sports competence was examined as a mediator, the best-fitting model versions explained 16% (R=0.16) MVPA variation, and 30% object control (R=0.30), and 12% locomotor skill variation (R=0.12) (reverse relationship). Perceived sports competence partially mediates the relationship between object control proficiency and physical activity for both directions and fully mediates the relationship between physical activity and locomotor skill; but only when locomotor skill is the outcome., Conclusions: If the relationship between object control skill and physical activity is viewed as a "positive feedback loop," skill development and increasing physical activity should simultaneously be targeted in physical activity interventions. Increasing perceived sport competence should also be an intervention focus., (© 2011 by the American College of Sports Medicine)

Background: The Exercise and Nutrition Routine Improving Cancer Health (ENRICH) study is investigating a novel lifestyle intervention aimed at improving the health behaviors of adult cancer survivors and their carers. The main purpose of the study is to determine the efficacy of lifestyle education and skill development delivered via group-based sessions on the physical activity and dietary behaviors of participants. This article describes the intervention development, study design, and participant recruitment., Methods/design: ENRICH is a randomized controlled trial, conducted in Australia, with two arms: an intervention group participating in six, two-hour face-to-face sessions held over eight weeks, and a wait-list control group. Intervention sessions are co-facilitated by an exercise physiologist and dietician. Content includes healthy eating education, and a home-based walking (utilizing a pedometer) and resistance training program (utilizing elastic tubing resistance devices). The program was developed with reference to social cognitive theory and chronic disease self-management models. The study population consists of cancer survivors (post active-treatment) and their carers recruited through community-based advertising and referral from health professionals. The primary outcome is seven-days of sealed pedometry. Secondary outcomes include: self-reported physical activity levels, dietary intake, sedentary behavior, waist circumference, body mass index, quality of life, and perceived social support. The outcomes will be measured at baseline (one week prior to attending the program), eight-weeks (at completion of intervention sessions), and 20-weeks. The intervention group will also be invited to complete 12-month follow-up data collection. Process evaluation data will be obtained from participants by questionnaire and attendance records., Discussion: No trials are yet available that have evaluated the efficacy of group-based lifestyle education and skill development amongst mixed groups of cancer survivors and their carers. The results will have implications for the planning and provision of health and support services during the cancer survivorship phase., Clinical Trials Registration: Australian New Zealand Clinical Trials Register identifier: ANZCTRN12609001086257.

The main aim of this study was to determine the test-retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.

Objective: To evaluate the feasibility and efficacy of the 'Healthy Dads, Healthy Kids' (HDHK) program, which was designed to help overweight fathers lose weight and be a role model of positive health behaviors for their children., Design: Randomized controlled trial., Participants: A total of 53 overweight/obese men (mean (s.d.) age=40.6 (7.1) years; body mass index (BMI)=33.2 (3.9)) and their primary school-aged children (n=71, 54% boys; mean (s.d.) age=8.2 (2.0) years) were randomly assigned (family unit) to either (i) the HDHK program (n=27 fathers, n=39 children) or (ii) a wait-list control group (n=26 fathers, n=32 children)., Intervention: Fathers in the 3-month program attended eight face-to-face education sessions. Children attended three of these sessions., Outcomes: The primary outcome was fathers' weight. Fathers and their children were assessed at baseline, and at 3- and 6-month follow-up, for weight, waist circumference, BMI, blood pressure, resting heart rate (RHR), objectively measured physical activity and self-reported dietary intake., Results: Intention-to-treat analysis revealed significant between-group differences at 6 months for weight loss (P<0.001), with HDHK fathers losing more weight (-7.6  kg; 95% confidence interval (CI) -9.2, -6.0; d=0.54) than control group fathers (0.0  kg; 95% CI -1.4, 1.6). Significant treatment effects (P<0.05) were also found for waist circumference (d=0.62), BMI (d=0.53), systolic blood pressure (d=0.92), RHR (d=0.66) and physical activity (d=0.91), but not for dietary intake. In children, significant treatment effects (P<0.05) were found for physical activity (d=0.74), RHR (d=0.51) and dietary intake (d=0.84)., Conclusion: The HDHK program resulted in significant weight loss and improved health-related outcomes in fathers and improved eating and physical activity among children. Targeting fathers is a novel and efficacious approach to improving health behavior in their children.

Background: Active travel to school (ATS) has been identified as an important source of physical activity for youth. However, the relationship between ATS and health-related fitness (HRF) among youth remains unclear., Methods: A systematic search of seven electronic databases (EMBASE, OVID MEDLINE, PsycINFO, PubMed, Scopus, SPORTDiscus and TRIS on line) was conducted in December 2009 and studies published since 1980 were considered for inclusion., Results: Twenty seven articles were identified that explored the relationship between ATS and the following aspects of HRF: weight status/body composition, cardiorespiratory fitness, muscular fitness and flexibility. Forty-eight percent of the studies that examined the relationship between ATS and weight status/body composition reported significant associations, this increased to 55% once poor quality studies were removed. Furthermore, the findings from five studies, including one longitudinal study, indicate that ATS is positively associated with cardiorespiratory fitness in youth. However, the evidence for the relationships between ATS and muscular fitness or flexibility is equivocal and limited by low study numbers., Conclusions: There is some evidence to suggest that ATS is associated with a healthier body composition and level of cardiorespiratory fitness among youth. Strategies to increase ATS are warranted and should be included in whole-of-school approaches to the promotion of physical activity., (© 2011 Lubans et al; licensee BioMed Central Ltd.)

Objective: To describe dietary changes in men participating in an obesity intervention as part of the Self-Help, Exercise and Diet using Information Technology (SHED-IT) study., Design: An assessor-blinded randomized controlled trial comparing Internet (n 34) v. information-only groups (n 31) with 6-month follow-up. Dietary intake assessed by FFQ, reporting usual consumption of seventy-four foods and six alcoholic beverages using a 10-point frequency scale. A single portion size (PSF) factor was calculated based on photographs to indicate usual serving sizes., Setting: The campus community of the University of Newcastle, New South Wales, Australia., Subjects: Sixty-five overweight/obese men (43 % students, 42 % non-academic general staff, 15 % academic staff; mean age 35.9 (sd 11.1) years, mean BMI 30.6 (sd 2.8) kg/m2)., Results: The average PSF decreased significantly over time (χ2 = 20.9, df = 5, P < 0.001) with no differences between groups. While both groups reduced mean daily energy intake (GLM χ2 = 34.5, df = 3, P < 0.001), there was a trend towards a greater reduction in the Internet group (GLM χ2 = 3.3, P = 0.07). Both groups reduced percentage of energy from fat (P < 0.05), saturated fat (P < 0.001) and energy-dense/nutrient-poor items (P < 0.05), with no change in dietary fibre or alcohol (P > 0.05)., Conclusions: Although men reported some positive dietary changes during weight loss, they did not increase vegetable intakes nor decrease alcohol consumption, while saturated fat, fibre and Na intakes still exceeded national targets. Future interventions for men should promote specific food-based guidelines to target improvements in their diet-related risk factor profile for chronic diseases.

This article reports the 12-month follow-up results and process evaluation of the SHED-IT (Self-Help, Exercise, and Diet using Information Technology) trial, an Internet-based weight loss program exclusively for men. Sixty-five overweight/obese male staff and students at the University of Newcastle (Callaghan, Australia) (mean (s.d.) age = 35.9 (11.1) years; BMI = 30.6 (2.8)) were randomly assigned to either (i) Internet group (n = 34) or (ii) Information only control group (n = 31). Both received one face-to-face information session and a program booklet. Internet group participants were instructed to use the study website for 3 months. Participants were assessed at baseline, 3-, 6-, and 12-month follow-up for weight, waist circumference, BMI, blood pressure, and resting heart rate. Retention at 3- and 12-months was 85% and 71%, respectively. Intention-to-treat (ITT) analysis using linear mixed models revealed significant and sustained weight loss of -5.3 kg (95% confidence interval (CI): -7.5, -3.0) at 12 months for the Internet group and -3.1 kg (95% CI: -5.4, -0.7) for the control group with no group difference. A significant time effect was found for all outcomes (P < 0.001). Per-protocol analysis revealed a significant group-by-time interaction for weight, waist circumference, BMI, and systolic blood pressure. Internet group compliers (who self-monitored as instructed) maintained greater weight loss at 12 months (-8.8 kg; 95% CI -11.8, -5.9) than noncompliers (-1.9 kg; 95% CI -4.8, 1.0) and controls (-3.0 kg; 95% CI -5.2, -0.9). Qualitative analysis by questionnaire and interview highlighted the acceptability and satisfaction with SHED-IT. Low-dose approaches to weight loss are feasible, acceptable, and can achieve clinically important weight loss in men after 1-year follow-up.

The mastery of fundamental movement skills (FMS) has been purported as contributing to children's physical, cognitive and social development and is thought to provide the foundation for an active lifestyle. Commonly developed in childhood and subsequently refined into context- and sport-specific skills, they include locomotor (e.g. running and hopping), manipulative or object control (e.g. catching and throwing) and stability (e.g. balancing and twisting) skills. The rationale for promoting the development of FMS in childhood relies on the existence of evidence on the current or future benefits associated with the acquisition of FMS proficiency. The objective of this systematic review was to examine the relationship between FMS competency and potential health benefits in children and adolescents. Benefits were defined in terms of psychological, physiological and behavioural outcomes that can impact public health. A systematic search of six electronic databases (EMBASE, OVID MEDLINE, PsycINFO, PubMed, Scopus and SportDiscus®) was conducted on 22 June 2009. Included studies were cross-sectional, longitudinal or experimental studies involving healthy children or adolescents (aged 3-18 years) that quantitatively analysed the relationship between FMS competency and potential benefits. The search identified 21 articles examining the relationship between FMS competency and eight potential benefits (i.e. global self-concept, perceived physical competence, cardio-respiratory fitness [CRF], muscular fitness, weight status, flexibility, physical activity and reduced sedentary behaviour). We found strong evidence for a positive association between FMS competency and physical activity in children and adolescents. There was also a positive relationship between FMS competency and CRF and an inverse association between FMS competency and weight status. Due to an inadequate number of studies, the relationship between FMS competency and the remaining benefits was classified as uncertain. More longitudinal and intervention research examining the relationship between FMS competency and potential psychological, physiological and behavioural outcomes in children and adolescents is recommended.

Objective: To investigate the impact of school garden-enhanced nutrition education (NE) on children's fruit and vegetable consumption, vegetable preferences, fruit and vegetable knowledge and quality of school life., Design: Quasi-experimental 10-week intervention with nutrition education and garden (NE&G), NE only and control groups. Fruit and vegetable knowledge, vegetable preferences (willingness to taste and taste ratings), fruit and vegetable consumption (24 h recall × 2) and quality of school life (QoSL) were measured at baseline and 4-month follow-up., Setting: Two primary schools in the Hunter Region, New South Wales, Australia., Subjects: A total of 127 students in Grades 5 and 6 (11-12 years old; 54 % boys)., Results: Relative to controls, significant between-group differences were found for NE&G and NE students for overall willingness to taste vegetables (P < 0·001) and overall taste ratings of vegetables (P < 0·001). A treatment effect was found for the NE&G group for: ability to identify vegetables (P < 0·001); willingness to taste capsicum (P = 0·04), broccoli (P = 0·01), tomato (P < 0·001) and pea (P = 0·02); and student preference to eat broccoli (P < 0·001) and pea (P < 0·001) as a snack. No group-by-time differences were found for vegetable intake (P = 0·22), fruit intake (P = 0·23) or QoSL (P = 0·98)., Conclusions: School gardens can impact positively on primary-school students' willingness to taste vegetables and their vegetable taste ratings, but given the complexity of dietary behaviour change, more comprehensive strategies are required to increase vegetable intake.

Background: Child and adolescent obesity predisposes individuals to an increased risk of morbidity and mortality from a range of lifestyle diseases. Although there is some evidence to suggest that rates of pediatric obesity have leveled off in recent years, this has not been the case among youth from low socioeconomic backgrounds. The purpose of this paper is to report the rationale, study design and baseline findings of a school-based obesity prevention program for low-active adolescent girls from disadvantaged secondary schools., Methods/design: The Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention will be evaluated using a group randomized controlled trial. NEAT Girls is a 12-month multi-component school-based intervention developed in reference to Social Cognitive Theory and includes enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity (PA) sessions, PA and nutrition handbooks, parent newsletters, pedometers for self-monitoring and text messaging for social support. The following variables were assessed at baseline and will be completed again at 12- and 24-months: adiposity, objectively measured PA, muscular fitness, time spent in sedentary behaviors, dietary intake, PA and nutrition social-cognitive mediators, physical self-perception and global self-esteem. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA and nutrition behavior change will be explored., Discussion: NEAT Girls is an innovative intervention targeting low-active girls using evidence-based behavior change strategies and nutrition and PA messages and has the potential to prevent unhealthy weight gain and reduce the decline in physical activity and poor dietary habits associated with low socio-economic status. Few studies have reported the long-term effects of school-based obesity prevention programs and the current study has the potential to make an important contribution to the field., Trial Registration: Australian New Zealand Clinical Trials Registry No: ACTRN12610000330044.

Purpose: The objective of this investigation was to examine the mechanisms of physical activity and dietary behavior change in the Program X intervention., Methods: Program X involved a clustered randomized controlled design with six schools (N=124 participants, mean age=14.1+/-0.8 years) randomized to intervention or control conditions for the 6-month study period. Physical activity and fruit and vegetable consumption were assessed using pedometers and questionnaires, respectively. The theoretical framework of the intervention was assessed using structural equation modeling, mediation, and moderation analyses., Results: The model explained 56% of the variance in physical activity at 6-months, but did not represent a good fit to the data, chi(2)=87.43, df=19, p < .001. The model explaining fruit and vegetable consumption explained 31% of the variance and provided a good fit to the data, chi(2)=12.40, df=10, p=.259. None of the variables satisfied the criteria for mediation or moderation in the physical activity model, but gender moderated the effects of intervention on fruit and vegetable consumption., Conclusions: None of the hypothesized mediators were responsible for behavior change in the Program X intervention. Future studies should address the limitations of existing psychosocial scales and continue to explore the mechanisms of behavior change using model testing, mediation, and moderation analyses., (Copyright (c) 2010 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the efficacy and feasibility of two school-based RT programs to improve muscular fitness and body composition in adolescents., Methods: The study was conducted in Australia from July 2008 to June 2009. Participants [n=108, mean age (SD)=15.0 (0.7) years] were randomized to free weights (n=37) or elastic tubing (n=41) RT groups and a control group was recruited (n=30). Participants in the RT groups completed 2 sets of 10-12 repetitions on 10 exercises for 8 weeks. Waist circumference, body composition (bioelectrical impedance analysis) and muscular strength (bench press and leg press) were assessed at baseline and posttest., Results: Boys (p<0.001) and girls (p<0.01) in both RT groups improved their body composition over the study period. Boys in both RT groups significantly improved both upper and lower body strength and their improvements were significantly greater than changes observed in the control group. Girls in the free weights groups achieved larger improvements in lower body strength compared to the control group (p<0.05)., Conclusions: Free weights and elastic tubing RT are feasible and effective strategies for improving aspects of health-related fitness in adolescents., (Copyright 2009 Published by Elsevier Inc. Published by Elsevier Inc. All rights reserved.)

Background: Statistical mediation analysis can be used to improve the design of obesity prevention and treatment programs by identifying the possible mechanisms through which an intervention achieved its effects. The aim of this study was to identify mediators of weight loss in an Internet-based weight-loss program specifically designed for overweight men., Methods: The Self-Help, Exercise and Diet using Information Technology (SHED-IT) program was a 3-month randomized controlled trial (Internet-based intervention group vs information only control group) that was implemented in 2007 with baseline and 6-month follow-up assessment of weight, physical activity and dietary behaviors. Intention-to-treat and per-protocol mediation analyses were conducted using a product-of-coefficients test., Results: Participants (N = 65) were overweight and obese male academic (n = 10) and non-academic (n = 27) staff and students (n = 28) from the University of Newcastle, Australia. Mean (SD) age = 35.9 (11.1) years and mean (SD) BMI = 30.6 (2.8). In the intention-to-treat analysis, both groups lost weight, but relative to the control group, the intervention did not have a statistically significant 'total effect' on weight, tau = -.507, p = .716 (95% CI = -3.277 to 2.263). In the per-protocol analysis, the intervention had a statistically significant 'total effect' on weight, tau = -4.487, p < .05 (95% CI = -8.208 to -.765). The intervention did not have a statistically significant effect on any of the hypothesized mediators and none of the behavioral variables mediated weight loss in the SHED-IT program. Although participants in the intervention group reduced their fat intake over the study period, the changes did not satisfy the criteria for mediation., Conclusion: Few studies have examined the mediators of weight loss in obesity treatment interventions. While none of the hypothesized mediators satisfied the criteria for mediation in the current study, there was some evidence to suggest that overweight men in the SHED-IT intervention reduced their fat intake over the study period. Future obesity treatment and prevention programs should explore behavioral mediators of weight loss using appropriate statistical methods., Trial Registration: Australian New Zealand Clinical Trials Registry No: ANZCTRN12607000481471.

The aim of this study was to evaluate the efficacy of an Internet-based weight-loss program for men in an assessor blinded randomized controlled trial. In total, 65 overweight/obese male staff and students at the University of Newcastle (mean (s.d.) age = 35.9 (11.1) years; BMI = 30.6 (2.8)) were randomly assigned to either (i) Internet group (n = 34) or (ii) control group (information only) (n = 31). Both groups received one face-to-face information session and a program booklet. Internet group participants used the study website to self-monitor diet and activity with feedback provided based on participants' online entries on seven occasions over 3 months. Participants were assessed at baseline, 3-, and 6-month follow-up for weight, waist circumference, BMI, blood pressure, resting heart rate, objectively measured physical activity, and self-reported total daily kilojoules. Intention-to-treat analysis revealed significant weight loss of 5.3 kg (95% confidence interval (CI): -7.3, -3.3) at 6 months for the Internet group and 3.5 kg (95% CI: -5.5, -1.4) for the control group. A significant time effect was found for all outcomes but no between-group differences. Per-protocol analysis revealed a significant group-by-time interaction (P < 0.001), with compliers losing more weight at 6 months (-9.1 kg; 95% CI -11.8, -6.5) than noncompliers (-2.7 kg; 95% CI -5.3, -0.01) and the control group (-4.2 kg; 95% CI -6.2, -2.2). Simple weight-loss interventions can be effective in achieving statistically and clinically significant weight loss in men. The Internet is a feasible and effective medium for weight loss in men but strategies need to be explored to improve engagement in online programs.

The primary objective of this study was to examine the relationship between heart rate intensity and pedometer step counts in adolescents. To determine cardiorespiratory fitness, 106 participants (47 boys, 59 girls, mean age 14.2 years, s = 0.8) completed the Queen's College Step Test and were classified as having low, moderate or high cardiorespiratory fitness. Adolescents also completed a 10-min treadmill trial while wearing a pedometer and heart rate monitor. The participants were instructed to maintain their heart rate between 65 and 75% of their maximum heart rate while running or walking on a treadmill. A heart rate of 65-75% maximum was associated with 146 steps per minute (s = 22) in boys and 137 steps per minute (s = 22) in girls. Results of analysis of variance indicated that there was a main effect for level of fitness (F(2,102) = 9.36, P < 0.001). The correlation between mean steps per minute and estimated maximum oxygen consumption was statistically significant (r = 0.44, P < 0.001). The results from this study suggest that a step rate of 130 steps per minute is equal to 65-75% maximum heart rate in low-fit adolescents and achieving 130 steps per minute could be used as an initial goal to improve fitness.

Background: While pedometers have an important role to play in the promotion of lifestyle activity among adults, less known is regarding their impact on behavior among youth (i.e. children and adolescents). The primary aim of this review was to identify the effectiveness of pedometers in promoting physical activity among youth. Secondary aims were to assess the quality of existing studies and examine the different ways that pedometers have been used to promote activity., Methods: A systematic search of six electronic databases was conducted using combinations of the following key words 'physical activity', 'walking', 'intervention', 'promotion', 'evaluation', and 'pedometer'. The quality of the studies was assessed against predetermined criteria., Results: Our search identified 14 studies, of which 12 resulted in increases in physical activity. Three studies used pedometers as open-loop feedback mechanisms to increase physical activity by making access to sedentary activities contingent on achieving activity targets. Ten studies used pedometers for self-monitoring and one study incorporated pedometers into an integrated school curriculum., Conclusions: Pedometers have been used successfully in a variety of ways to promote activity among youth. Since there are so few studies at this time, there is ample need and opportunity to contribute to the knowledge base.

Purpose: The objective of this study was to evaluate the impact of a school-based intervention (Program X) incorporating pedometers and e-mail support on physical activity, sedentary behavior, and healthy eating in adolescents., Methods: A randomized control trial was used to evaluate the impact of the Program X intervention. Six schools (N = 124 participants; mean age 14.1 +/- .8 years) were randomized to intervention or control conditions for the 6-month study period. Objectively recorded physical activity (mean steps/day), self-reported sedentary behavior, and dietary habits were measured at baseline and at 6-month follow-up and intervention effects were assessed using repeated-measures analysis of variance and chi(2) tests., Results: Participants in the intervention group increased their step counts by 956 +/- 4107 steps/day (boys) and 999 +/- 1999 (girls). Repeated-measures analysis of variance revealed significant group-by-time interactions for boys (F = 7.4, p = .01, d = .80) and girls (F = 29.6, p <.001, d = 1.27) for mean steps/day. The intervention significantly decreased the number of energy-dense/low-nutrient snacks consumed by boys (chi(2) = 4.0, p = .043) and increased the number of fruit serves among girls (chi(2) = 4.8, p = .028). The intervention did not have a statistically significant effect on sedentary behavior., Conclusion: A school-based intervention incorporating physical activity monitoring using pedometers and e-mail support was successful in promoting physical activity and selected healthy eating behaviors in adolescent boys and girls.

It has been suggested that the low level of effectiveness of youth interventions is due to a lack of knowledge regarding the mechanisms responsible for behaviour change. The identification of behaviour mediators is necessary for the progression of physical activity research, as it allows researchers to determine which components of an intervention are responsible for mediating behaviour change. The purpose of this study was to identify mediators of behaviour change in a physical activity intervention for senior school students. Participants (n=78) were randomly allocated to control or intervention conditions for a period of 10 weeks. Moderate-to-vigorous physical activity (MVPA) and potential mediators were assessed at baseline and post-intervention (10 weeks). Hypothesized mediators were derived from Bandura's Social Cognitive Theory and included: peer support, exercise self-efficacy and outcome expectancy. Mediation was assessed using the product-of-coefficients test described by MacKinnon and colleagues, based on the criteria for mediation identified by Baron and Kenny. While none of the variables satisfied all four criteria for mediation among males or females, self-efficacy was able to satisfy the first three criteria among females in the study. Exercise self-efficacy may be a mediator of physical activity behaviour in adolescent girls.

The purpose of this study was to examine potential correlates of objectively measured physical activity among a sample of Australian adolescents. Participants were 119 14-15 year old students from three secondary schools. Students wore pedometers for 4 consecutive school days and completed questionnaires assessing demographic, social, psychological and behavioural correlates of physical activity. Mean steps/day were 11,865 (+/-3997) for boys (n=47) and 9466 (+/-3195) for girls (n=72). Approximately one-third of boys (32%) and girls (33%) satisfied existing step recommendations (girls 11,000 steps/day and boys 13,000 steps/day). In the first instance, the relationship between factors and physical activity was assessed using bivariate correlation. Enjoyment of physical activity (r=0.37, p<0.05), use of self-management strategies (r=0.33, p<0.05) and perceived barriers (r=-0.39, p<0.05) were significantly related to mean steps/day among boys. Peer support (r=0.26, p<0.05) and the use of self-management strategies (r=0.30, p<0.05) were significantly associated with mean steps/day for girls. Hierarchical regression analysis revealed that gender, peer support, self-management strategies and perceived barriers accounted for 16% of the variance in mean steps/day. This study has identified a number of potentially modifiable correlates of objectively measured physical activity in sample of Australian adolescents.

Background: The effectiveness of interventions to promote physical activity in youths is still developing. To develop a better understanding "what works", researchers are now focusing on constructing an evidence base for mediators of behavior change., Methods: We reviewed studies that examined the direct effect of physical activity interventions on hypothesized mediators and the relationship between mediators and physical activity in young people (aged 5 to 18 years). Studies were identified via electronic database searches and scanning references against predetermined quality criteria., Results: We found seven studies that evaluated three mediator groups: cognitive, behavioral and interpersonal mediators. Self-efficacy was the most commonly assessed mediator in youth interventions and there was strong support for its role in mediating the relation between theory-based interventions and physical activity. There was some support for the importance of behavioral strategies as mediators of behavior, but no support for the mediating influence of interpersonal factors., Conclusions: Despite recognition of the importance of mediation studies, few interventions have assessed mediators of physical activity behavior in youth interventions. The small number of studies examining mediators of behavior and the variability in study design and quality prevent us from forming strong conclusions regarding the most effective mediators of behavior.