School-based physical activity intervention in 11-13-year-olds: study protocol for cluster randomized controlled trial

ABSTRACT

Background:Targeted strategies to enhance regular physical activity appear to be promising to promote health and well-being of adolescents.This article reports the design of a cluster randomised controlled trial to evaluate the effectiveness of a school-based physical activity programme on the rate and duration of moderate-to-vigorous physical activity, sitting time including screen time, andhealth-related physical fitness parameters among 11-13 year-old adolescents.Methods:This is a cluster randomized controlled trial conducted in 360 adolescents fromgovernment schools in the Colombo Municipal Council area, Sri Lanka. An individual school wasconsidered as a unit of randomization and the 12 selected schools were randomly assigned to one of twogroups control (sixschools) and intervention groups (sixschools). The intervention group follows aphysical activity programme for 30 minutes on threeschool days per week, for threeconsecutive months in addition to the standard practice. The primary outcomes are moderate-to-vigorous physical activity rate and duration and sitting time including screen time. Secondary outcomes are the health-related physical fitness parameters cardiovascular fitness, muscle fitness and flexibility, and body composition. All the outcomes are measured at baseline and three-months following the intervention.Discussion:The outcomes of this study will be an evidence-based intervention programme with the potential to be incorporated into the national education system thus promoting health and well-being of adolescents in Sri Lanka. Trial Registration Registered at the Sri Lanka Clinical Trials Registry (SLCTR/2018/028).