Interactions between physical activity and the environment to improve adolescent psychological wellbeing: a randomised controlled trial

Natural environments promote physical activity (PA) and are psychologically restorative. In adults, performing PA in nature provides additive benefits for self-esteem (SE). Studies in adolescents indicate no such effect. However, they have not examined the effect of interaction with natural environments. The aim of this study was to analyse the effects of exercising in natural and built environments on adolescent PA and SE. Sixty adolescents participated in a natural and built orienteering course in a randomised order. PA was assessed throughout whilst SE was assessed pre- and post-intervention. There was a significant effect for PA due to environment (P < 0.001) and sex (P < 0.01). Almost half the time in the natural environment was spent in moderate to vigorous PA, compared to a quarter in the built. The PA significantly improved SE (P < 0.05); however there was no environmental effect (P > 0.05). Natural environments should be used as a tool for engaging adolescents in PA.

Nutritional Evaluation and Optimisation in Neonates: a randomized, double-blind controlled trial of amino acid regimen and intravenous lipid composition in preterm parenteral nutrition

Background: Parenteral nutrition is central to the care of very immature infants. Current international recommendations favor higher amino acid intakes and fish oil–containing lipid emulsions. Objective: The aim of this trial was to compare 1) the effects of high [immediate recommended daily intake (Imm-RDI)] and low [incremental introduction of amino acids (Inc-AAs)] parenteral amino acid delivery within 24 h of birth on body composition and 2) the effect of a multicomponent lipid emulsion containing 30% soybean oil, 30% medium-chain triglycerides, 25% olive oil, and 15% fish oil (SMOF) with that of soybean oil (SO)-based lipid emulsion on intrahepatocellular lipid (IHCL) content. Design: We conducted a 2-by-2 factorial, double-blind, multicenter randomized controlled trial. Results: We randomly assigned 168 infants born at ,31 wk of gestation. We evaluated outcomes at term in 133 infants. There were no significant differences between Imm-RDI and Inc-AA groups for nonadipose mass [adjusted mean difference: 1.0 g (95% CI: 2108, 111 g; P = 0.98)] or between SMOF and SO groups for IHCL [adjusted mean SMOF:SO ratio: 1.1 (95% CI: 0.8, 1.6; P = 0.58]. SMOF does not affect IHCL content. There was a significant interaction (P = 0.05) between the 2 interventions for nonadipose mass. There were no significant interactions between group differences for either primary outcome measure after adjusting for additional confounders. Imm-RDI infants were more likely than Inc-AA infants to have blood urea nitrogen concentrations .7 mmol/L or .10 mmol/L, respectively (75% compared with 49%, P , 0.01; 49% compared with 18%, P , 0.01). Head circumference at term was smaller in the Imm-RDI group [mean difference: 20.8 cm (95% CI: 21.5, 20.1 cm; P = 0.02)]. There were no significant differences in any prespecified secondary outcomes, including adiposity, liver function tests, incidence of conjugated hyperbilirubinemia, weight, length, mortality, and brain volumes. Conclusion: Imm-RDI of parenteral amino acids does not benefit body composition or growth to term and may be harmful. This trial was registered at www.isrctn.com as ISRCTN29665319 and at eudract.ema.europa.eu as EudraCT 2009-016731-34.