http://repub.eur.nl/res/aut/25687/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/32148/ 2012-04-18T00:00:00Z This thesis aimed to answer two research questions: 1. How is the physical environment associated with PA behaviour among adolescents? 2. What are the effects of a computer-tailored intervention (YouRAction) that targets individual level factors and of a computer-tailored intervention that targets individual and environmental level factors on compliance with the MVPA guideline among Dutch adolescents? It was concluded that there is no evidence for a direct association between the objectively measured physical environment and PA among urban adolescents. However, even though there was no direct association between the physical environment and PA among adolescents, the physical environment was found to be an important factor in combination with social environmental or cognitive factors. When adolescents had a high intention or high level of NSC in combination with high availability of facilities, they were more likely to participate in sports or increase their sports participation. It was also concluded that the YouRAction and YouRAction+e interventions were not effective in increasing compliance to the MVPA guideline, which might be due to sub-optimal implementation of the intervention. http://repub.eur.nl/res/pub/26751/ 2011-08-01T00:00:00Z Objective. The objective of the present study was to assess the longitudinal association between cycling to school and weight status in two cities where cycling to school is common Kristiansand (Norway) and Rotterdam (The Netherlands). Methods. Data from two studies ENDORSE (Rotterdam) and YOUTH IN BALANCE (Kristiansand) were used. Both studies were longitudinal with two years between time (T) 1 and T2 measurements, and with mean age at T1 of 13.2 and 13.4 years, respectively. The sample was categorized into the following groups according to responses about main mode of commuting to school at the two time points: NO cycling, STARTED cycling, STOPPED cycling and CONTINUED cycling. Measured weight and height were obtained at both time points, and weight status (overweight vs. not overweight) was calculated using international classification criteria for BMI. The two datasets were analyzed separately and together. Results. In multilevel logistic regression models of the combined sample, adjusting for weight status at Time 1, those who stopped cycling had greater odds of being overweight at T2 (OR = 3.19; 95% CI = 1.417.24) while those continued cycling had lower odds of being overweight (OR = 0.44; 95% CI = 0.210.88), separately compared to the other three groups together. The same trend was observed in both study samples. Conclusions. This study shows that there are longitudinal associations between cycling to school and weight status in two cities where cycling to school is common, implying that interventions aiming at reducing overweight/obesity among adolescents might consider the promotion of sustained cycling behaviour. http://repub.eur.nl/res/pub/21031/ 2010-08-13T00:00:00Z Background. Increasing physical activity (PA) among adolescents is an important health promotion goal. PA has numerous positive health effects, but the majority of Dutch adolescents do not meet PA requirements. The present paper describes the systematic development of a theory-based computer-tailored intervention, YouRAction, which targets individual and environmental factors determining PA among adolescents. Design. The intervention development was guided by the Intervention Mapping protocol, in order to define clear program objectives, theoretical methods and practical strategies, ensure systematic program planning and pilot-testing, and anticipate on implementation and evaluation. Two versions of YouRAction were developed: one that targets individual determinants and an extended version that also provides feedback on opportunities to be active in the neighbourhood. Key determinants that were targeted included: knowledge and awareness, attitudes, self-efficacy and subjective norms. The extended version also addressed perceived availability of neighbourhood PA facilities. Both versions aimed to increase levels of moderate-to-vigorous PA among adolescents. The intervention structure was based on self-regulation theory, comprising of five steps in the process of successful goal pursuit. Monitoring of PA behaviour and behavioural and normative feedback were used to increase awareness of PA behaviour; motivation was enhanced by targeting self-efficacy and attitudes, by means of various interactive strategies, such as web movies; the perceived environment was targeted by visualizing opportunities to be active in an interactive geographical map of the home environment; in the goal setting phase, the adolescents were guided in setting a goal and developing an action plan to achieve this goal; in the phase of active goal pursuit adolescents try to achieve their goal and in the evaluation phase the achievements are evaluated. Based on the results of the evaluation adolescents could revise their goal or choose another behaviour to focus on. The intervention is delivered in a classroom setting in three lessons. YouRAction will be evaluated in a cluster-randomized trial, with classes as unit of randomization. Evaluation will focus on PA outcomes, cognitive mediators/moderators and process measures. Discussion. The planned development of YouRAction resulted in two computer-tailored interventions aimed at the promotion of PA in a Dutch secondary school setting. Trial registration. NTR1923. http://repub.eur.nl/res/pub/27841/ 2010-06-04T00:00:00Z This longitudinal study aimed to identify individual and environmental predictors of adolescents' sports participation and to examine whether availability of sports facilities moderated the intention-behaviour relation. Data were obtained from the ENvironmental Determinants of Obesity in Rotterdam SchoolchildrEn study (2005/2006 to 2007/2008). A total of 247 adolescents (48% boys, mean age at follow-up 15 years) completed the surveys at baseline and follow-up. At baseline, adolescents completed a survey that assessed engagement in sports participation, attitude, subjective norm, perceived behavioural control and intention towards sports participation. Availability of sports facilities (availability) was assessed using a geographic information system. At follow-up, sports participation was again examined. Multiple logistic regression analyses were conducted to test associations between availability of sports facilities, theory of planned behaviour variables and the interaction of intention by availability of sports facilities, with sports participation at follow-up. Simple slopes analysis was conducted to decompose the interaction effect. A significant availability × intention interaction effect [odds ratio: 1.10; 95% confidence interval: 1.00-1.20] was found. Simple slopes analysis showed that intention was more strongly associated with sports participation when sports facilities were more readily available. The results of this study indicate that the intention-sports participation association appears to be stronger when more facilities are available. http://repub.eur.nl/res/pub/25341/ 2009-10-15T00:00:00Z Background: This study examined the associations of the perceived and objective environment with adolescent engagement in sports activities and walking and cycling in leisure time. It also explored the degree of agreement between objective and perceived availability of physical activity (PA) facilities in neighborhoods. Methods: Cross-sectional data on physical activity, the perceived availability of physical activity opportunities (perceived physical environment) was assessed through a questionnaire and the objective availability of PA opportunities (objective physical environment) was obtained through GIS data. The final sample included 654 adolescents with a mean age of 14.1 (SD = 1.2) years. Results: Perceived availability of sports facilities and parks was significantly associated with engaging in sports (OR: 1.73; 95% CI: 1.16-2.56) and with walking and cycling in leisure time (OR: 1.66; 95% CI: 1.07-2.57) respectively. Agreement between objective and perceived environment was low to moderate with Kappa values ranging from -0.005 to 0.053. Conclusion: The perceived environment was the stronger correlate of PA behavior among adolescents. There were substantial differences between assessments of objective and perceived physical environment.