https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:23597 Wed 11 Apr 2018 16:32:58 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27083 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.]]> Wed 11 Apr 2018 16:06:47 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36287 -1. 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 (-1.4 cm; 95% CI, -4.7-1.9). At 6 months, there were intervention effects for RT skill competency and self-efficacy, but no other secondary outcomes. Effects for upper body MF and RT skill competency were sustained at 12 months. Despite overall no effect for body mass index, there was a group-time effect at 12 months among students whowere overweight/obese at baseline (-0.55 kg·m^-2; 95% CI, -1.01 to -0.08). Conclusions: The school-based RT intervention resulted in immediate and sustained improvements in upper body MF and RT skill competency, demonstrating an effective and scalable approach to delivering RT within secondary schools.]]> Thu 19 Mar 2020 17:51:33 AEDT ]]>