A Classroom-Based Intervention for Reducing Sedentary Behavior and Improving Spinal Health: Pragmatic Stepped-Wedge Feasibility Randomized Controlled Trial
Authors: Fisher Dominic , Maart Rentia , Thabane Lehana , Louw Quinette 
Published: November 2024

Background
Noncommunicable diseases (NCDs) resulting from sedentary behavior (SB) are adding a 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, allowing learners to interrupt prolonged bouts of sitting with standing without interrupting their school work. Alternating between sitting and standing also benefits spinal health by interrupting prolonged periods of high spinal loading, but no such intervention has been trialed in South Africa. The potential to reduce strain on the health system by reducing the incidence of NCDs and improving spinal health requires further consideration. Before embarking on a large classroom-based trial, it is essential to determine the acceptability of the intervention, its impact on teachers’ practices, and the logistical and pragmatic considerations of data collection.

Objective
This study aimed to assess the feasibility of implementing a classroom-based intervention to reduce SB and improve spinal health in primary school learners, to assess the pragmatics of delivering and adherence to the intervention, and assess the pragmatics of measuring physical activity and postural dynamism data with wearable sensors.

Methods
We used a stratified, closed-cohort, randomized, 2-cluster, stepped-wedge design with a pragmatic approach. One grade 5 and grade 6 class each was recruited from contrasting socioeconomically categorized, state-funded primary schools in the Western Cape province, South Africa. Classroom furniture was substituted with sit-stand desks, and health education and movement videos (HEMVs) were shown during class time. Skin-mounted activPAL physical activity monitors were used to measure SB and postural topography and Noraxon myoMOTION inertial measurement units (IMUs) to measure spinal movement. The study was evaluated for feasibility by tracking school retention, successful delivery of the HEMVs, the use of sit-stand desks, compliance with the wearable sensors, and data accuracy. We deductively analyzed teachers’ interviews and learners’ focus groups using Atlas.ti 9 software. Descriptive analysis of quantitative data was performed using Microsoft Excel.

Results
Cluster 1 withdrew from the study before follow-up SB, postural topography, and spinal movements were measured. All feasibility outcomes, namely (1) classroom retention, (2) delivery of HEMVs, (3) learner and teacher acceptance and usage of sit-stand classroom furniture, (4) 100% compliance with wearing skin-mounted sensors for the duration of the intended measurement period, and (5) minimum 80% eligibility of sensor data gathered included in data analysis, were met in cluster 2. 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 contextualized teacher training on how sit-stand desks and HEMVs can be used as classroom management tools.

Trial Registration
Pan African Trials Registry PACTR201811799476016; https://tinyurl.com/y4upoys8

International Registered Report Identifier (IRRID)
RR2-10.2196/18522