What helps children to move more at school recess and lunchtime? Mid-intervention results from Transform-Us! cluster-randomised controlled trial

Background iv>To investigate the interpersonal and physical environment mediators of the Transform-Us! mid-intervention effects on physical activity (PA) during recess and lunchtime.

Methods
Transform-Us! is a clustered randomised school-based intervention with four groups: sedentary behaviour intervention (SB-I), PA intervention (PA-I), combined PA+SB-I and control group. All children in grade 3 from 20 participating primary schools in Melbourne, Australia were eligible to complete annual evaluation assessments. The outcomes were the proportion of time spent in moderate-to-vigorous PA (MVPA) and light PA (LPA) during recess and lunchtime assessed by accelerometers. Potential mediators included: perceived social support from teachers; perceived availability of line markings; perceived accessibility of sports equipment; and perceived school play environment. Generalised linear models were used and mediation effects were estimated by product-of-coefficients (a·b) approach.

Results
268 children (8.2 years, 57% girls at baseline) provided complete data at both time points. A significant intervention effect on MVPA during recess in the SB-I and PA-I groups compared with the control group (proportional difference in MVPA time; 38% (95% CI 21% to 57%) and 40% (95% CI 20% to 62%), respectively) was found. The perceived school play environment was significantly positively associated with MVPA at recess among girls. An increase in perceived social support from teachers suppressed the PA+SB-I effect on light PA during recess (a·b= −0.03, 95% CI −0.06 to −0.00). No significant mediating effects on PA during recess and lunchtime were observed.

Conclusions
A positive perception of the school play environment was associated with higher MVPA during recess among girls. Future studies should conduct mediation analyses to explore underlying mechanisms of PA interventions.iv>

Changes in the nutritional composition of captive early-mid stage Panulirus ornatus phyllosoma over ecdysis and larval development

Elucidation of the key nutritional requirements for complete larval development of the tropical spiny rock lobster, Panulirus ornatus, presents a major challenge for the development of robust commercial aquaculture for this crustacean. As a foundation study in this area, the chemical composition of early-mid stage P. ornatus phyllosoma (Stages I-VI) receiving a novel formulated diet was analysed immediately prior and post-ecdysis to provide insight into the crude nutritional trends during the larval development cycle. From the onset of moulting, cyclical patterns were evident in the proximate composition of phyllosoma, resulting in substantial restructuring between the pre- and post-moult stages of the moult cycle. Proportions of protein, lipid and ash were high at the premoult stage, reflecting growth and nutrient accumulation over the intermoult period, and reduced at the post-moult stage, reflecting the large uptake of water to facilitate subsequent growth. Polar lipid was the dominant lipid class, accounting for >. 90% of the total lipid content. Conversely, triacylglycerol concentrations were low (<. 5%), despite being the principal lipid class available in the formulated diet. Likewise, despite receiving high concentrations of eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) (9.2 and 7.6% of the dietary lipid source, respectively), levels of these fatty acids were comparatively low in phyllosoma (3.4 and 4.7%, respectively). In contrast, there is selective deposition of these fatty acids in wild caught phyllosoma. This finding suggests a poor assimilation of triacylglycerols by captive larvae and highlights the importance of future investigations into alternative sources of EPA and DHA. Ultimately, this study provides insight into the nutritional requirements of phyllosoma, providing valuable knowledge on diet formulation for commercially viable hatchery production of spiny rock lobsters. © 2014 Elsevier B.V.

The effect of low parental warmth and low monitoring on disordered eating in mid-adolescence: findings from the Australian Temperament Project

OBJECTIVE: To investigate the interactions between low parental warmth and monitoring at age 13-14 years and disordered eating attitudes and behaviours at age 15-16 years. METHOD: Data on 1300 (667 females) adolescents and their parents were drawn from The Australian Temperament Project (ATP), a 30 year (15 wave) population based longitudinal study of social-emotional development. Parent participants completed surveys on parenting practices in late childhood, and adolescent participants reported disordered eating using the drive for thinness and bulimia subscales of the Eating Disorder Inventory (EDI) and an additional body dissatisfaction scale. Interaction was examined on the additive scale by estimating super-additive risk; i.e., risk in excess of the sum of individual risks. RESULTS: For boys, neither parental warmth or monitoring, nor their interaction, was related to disordered eating. For girls, low parental warmth (alone) was associated with bulimic behaviours. In contrast, exposure to both low monitoring and warmth was associated with &sim;3½-fold, &sim;4-fold and &sim;5-fold increases in the odds of reporting body dissatisfaction, drive for thinness and bulimia, respectively. For body dissatisfaction and drive for thinness, risk associated with joint exposure exceeded the sum of individual risks, suggesting an additive interaction between parenting styles. CONCLUSION: Further investment in family-level interventions that focus on promoting parental monitoring behaviour and a warm parent-child relationship remain important strategies for preventing a range of disordered eating behaviours in adolescents.