‘Stand Up For Health’ an intervention to reduce adolescent sitting time during the school day

INTERVENTION: ‘Stand up for Health’ an intervention to reduce adolescent sitting time during the school day. 6 month, 2‐arm cluster RCT involving at least 120 students recruited from four secondary schools. The four schools will be pair matched based on their physical space, the number of students in Years 7 and 8, and the SES of enrolled students’ parents. All students in Years 7 and 8 will be invited to participate with parental consent. The class with the greatest number of consenting students will be selected to participate. Following baseline measures, each pair of centres will be randomised into the intervention group (n=2) or the control group (n=2). The duration of the intervention will be 3 months. The intervention will employ strategies to reduce participants sitting time. In some instances all of the classroom students will be included in the measures, for example‐ breaking up sitting time by having the students break half way through class time (approximately every 30 minutes) to stand up and stretch for 2 minutes. In other instances only the study participants will be involved in the measures: e.g.participants will spend 30 minutes each day at standing desks at the rear of the classroom. They will be encouraged to use the outdoor standing tables each day at lunch for the intervening period of the study. Personal Development, Health and Physical Education teachers will be asked to deliver a series of modules to their entire class over the intervention period (in the two intervention schools). The modules will be theoretically based using the social cognitive, behavioural choice and ecological systems theories. The modules will be delivered in 8 lessons for a 15‐20 minute period. Teachers will incorporate the lessons into their timetable when it is feasible during the intervention period (3months). Students will be given relevant activities to take home and complete to further their understanding of the class content (e.g. sedentary behaviour diary). Research staff will meet with staff involved in the study to explain the intervention and modules. The teachers will be provided with lesson plans and encouraged to modify them to suit their lesson and teaching style. Lessons will focus on raising awareness about sedentary behaviour. Key messages will focus on self‐monitoring and goal setting, involving students in behavioural contracts, providing social support such as team based activities and home work involving family members and feedback and reinforcement. Ideas will be provided for classroom teachers to encourage standing time, eg: rotation of activities around the classroom. This will include fidelity of implementation of each component of the Program, consistency of implementation across the sites and barriers to implementation. School staff will document this at the end of each week and it will be validated by the Project Manager on a random selection of 10% of days using established procedures. Attendance rates for each student will also be collected to account for the dose of intervention received. CONDITION: Cognition and Executive function Overweight/Obese Sitting time PRIMARY OUTCOME: Potential efficacy/behaviour change in reducing adolescents school day sedentary behaviour, assessed with an actigraph accelerometer and an activpal device. Potential efficacy/change in cognition as assessed by the Figural Intersections Task (FIT) and Executive function assessed by the Matrix reasoning test SECONDARY OUTCOME: Acceptability/Feasibility of the program. Intervention implementation: Fidelity and consistency of the program. INCLUSION CRITERIA: Participants with a minimum age 12 years and maximum age of15 years The intervention will be guided by the Social Cognitive Theory and based on the four key processes for learning and adapting new behaviours: attention, retention, production, and motivation (Bandura 1977). Regarding each of these processes, the activities have been designed to: (a) include stimulus material and specific lesson activities that engage and direct the attention of the teachers and students; (b) match students’ cognitive and behavioural skill levels and provide opportunities to enhance mastery experiences; (c) include incentives that are relevant, attractive and specified prior to the learning activities; and (d) emphasise perceived choice and control, as well as personalisation, contextualisation, challenge, curiosity and mastery through activities that enhance intrinsic motivation, greater persistence, better performance and higher satisfaction.