Reducing sedentary behaviour and improving spinal health in South African primary school children: findings of a pragmatic stepped-wedge feasibility randomized controlled trial (Preprint)

BACKGROUND Non-communicable diseases resulting from sedentary behaviour (SB) are adding further strain on the South African health system, which is already struggling to manage infectious diseases. Some countries have enabled children to reduce SB at school by substituting traditional furniture with sit-stand classroom furniture. Alternating between sitting and standing benefits spinal health, but no such intervention exists in South Africa. It is therefore essential to consider several contextual factors, such as the acceptability of the intervention, its impact on teachers' practices, and the logistical and pragmatic considerations of data collection. This study therefore aimed to assess the feasibility of implementing a classroom-based intervention to reduce SB and improve spinal health in primary school learners. OBJECTIVE The study objectives were to assess the pragmatics of delivering and adherence to a classroom-based intervention and assess the pragmatics of measuring physical activity and postural dynamism data with activPAL and Noraxon Myomotion inertial measurement units (IMUs), respectively. METHODS We used a stratified, closed-cohort, randomised, two-cluster, stepped-wedge design with a pragmatic approach. One grade 5 and 6 class each were recruited from contrasting socio-economically categorised, publicly funded primary schools in the Western Cape Province, South Africa. Classroom furniture was substituted with sit-stand desks and health and movement videos were shown during class time. Skin-mounted activPAL physical activity monitors and Noraxon Myomotion Inertial measurement units were used to measure SB and spinal movement respectively. The study was evaluated for feasibility by tracking school retention, successful delivery of the videos and use of the desks, compliance with the wearable sensors, and data accuracy. We deductively analysed teacher interviews and learners' focus groups using Atlas.ti 9 software. Descriptive analysis of quantitative data was done using Microsoft Excel. RESULTS All feasibility outcomes were met in cluster two. Cluster one withdrew from the study before follow-up SB, postural topography and spinal movements were measured. The study found that it is feasible to conduct a larger trial with minor modifications to the methodology. CONCLUSIONS We recommend a whole-school approach to support the intervention and a monitoring strategy to track the impact of the intervention on the classroom. Furthermore, we recommend contextualised teacher training on how sit-stand desks and health education videos can be utilised as classroom management tools. CLINICALTRIAL Pan African Trials Registry PACTR201811799476016; Registered 22 November 2018 – retrospectively registered; https://tinyurl.com/y4upoys8 INTERNATIONAL REGISTERED REPORT RR2-10.2196/18522