Screen-based activities, such as watching television (TV), playing video games, and using computers, are common sedentary behaviors among young people and have been linked with increased energy intake and overweight. Previous home-based sedentary behaviour interventions have been limited by focusing primarily on the child, small sample sizes, and short follow-up periods. The SWITCH (Screen-Time Weight-loss Intervention Targeting Children at Home) study aimed to determine the effect of a home-based, family-delivered intervention to reduce screen-based sedentary behaviour on body composition, sedentary behaviour, physical activity, and diet over 24 weeks in overweight and obese children. A two-arm, parallel, randomized controlled trial was conducted. Children and their primary caregiver living in Auckland, New Zealand were recruited via schools, community centres, and word of mouth. The intervention, delivered over 20 weeks, consisted of a face-to-face meeting with the parent/caregiver and the child to deliver intervention content, which focused on training and educating them to use a wide range of strategies designed to reduce their child’s screen time. Families were given Time Machine TV monitoring devices to assist with allocating screen time, activity packages to promote alternative activities, online support via a website, and monthly newsletters. Control participants were given the intervention material on completion of follow-up. The primary outcome was change in children’s BMI z-score from baseline to 24 weeks. Children (n = 251) aged 9-12 years and their primary caregiver were randomized to receive the SWITCH intervention (n = 127) or no intervention (controls; n = 124). There was no significant difference in change of zBMI between the intervention and control groups, although a favorable trend was observed (-0.016; 95% CI: -0.084, 0.051; p = 0.64). There were also no significant differences on secondary outcomes, except for a trend towards increased children’s moderate intensity physical activity in the intervention group (24.3 min/d; 95% CI: -0.94, 49.51; p = 0.06). A home-based, family-delivered intervention to reduce all leisure-time screen use had no significant effect on screen-time or on BMI at 24 weeks in overweight and obese children aged 9-12 years. Australian New Zealand Clinical Trials Registry Website: http://www.anzctr.org.au Trial registration number: ACTRN12611000164998
Intervention strategies for promoting long-term weight loss are examined empirically and conceptually. Weight control research over the last 20 years has dramatically improved short-term treatment efficacy but has been less successful in improving long-term success. Interventions in preadolescent children show greater long-term efficacy than in adults. Extending treatment length and putting more emphasis on energy expenditure have modestly improved long-term weight loss in adults. Fresh ideas are needed to push the field forward. Suggested research priorities are patient retention, natural history, assessment of intake and expenditure, obesity phenotypes, adolescence at a critical period, behavioral preference-reinforcement value, physical activity and social support, better linkage of new conceptual models to behavioral treatments, and the interface between pharmacological and behavioral methods.
To increase participation in physical activity, it is important to understand the factors associated with a child's choice to be physically active or sedentary. The neighborhood and home environments may be related to this choice.To determine whether the neighborhood environment or number of televisions in the home environment are independently associated with child physical activity and television time.The associations of the neighborhood and home environments on active and sedentary behaviors were studied in 44 boys and 44 girls who wore accelerometers and recorded their television watching behaviors. Neighborhood environment variables were measured using extensive geographic information systems analysis.Hierarchical regression analyses were used to predict physical activity after controlling for individual differences in age, socioeconomic status, percentage overweight, and time the accelerometer was worn in Step 1. Sex of the child was added in Step 2. A neighborhood design variable, street connectivity, accounted for an additional 6% (p
There is limited research on how taxes and subsidies would influence the energy and nutritional quality of food purchases. Using an experimental analogue purchasing task, we examined the effects of increasing the price of high-calorie-for-nutrient foods or reducing the price of low-calorie-for-nutrient foods by 12.5% and 25% on mothers’ purchases of 68 common foods and drinks. Taxing less healthy foods with low nutrient density reduced energy (caloric) intake, while reducing the proportion of fat and increasing the proportion of protein purchased. Subsidizing more healthful foods with high nutrient density increased energy intake, without changing the macronutrient profile of foods purchased. These results favor taxes as a way to reduce caloric intake.
