Impact of an 8-Month Trial Using Height-Adjustable Desks on Children’s Classroom Sitting Patterns and Markers of Cardio-Metabolic and Musculoskeletal Health

Abstract

During school hours, children can sit for prolonged and unbroken periods of time. This study investigated the impact of an 8-month classroom-based intervention focusing on reducing and breaking-up sitting time on children’s cardio-metabolic risk factors (i.e., body mass index, waist circumference, blood pressure) and perceptions of musculoskeletal discomfort. Two Year-6 classes (24 students per class) in one primary school were assigned to either an intervention or control classroom. The intervention classroom was equipped with height-adjustable desks and the teacher was instructed in the delivery of pedagogical strategies to reduce and break-up sitting in class. The control classroom followed standard practice using traditional furniture. At baseline, and after 8-months, time spent sitting, standing, stepping, and sitting-bouts (occasions of continuous sitting) as well as the frequency of sit-to-stand transitions were obtained from activPAL inclinometers and the time spent in light-intensity physical activity was obtained from ActiGraph accelerometers. Demographics and musculoskeletal characteristics were obtained from a self-report survey. Hierarchical linear mixed models found that during class-time, children’s overall time spent sitting in long bouts (>10 min) were lower and the number of sit-to-stand transitions were higher in the intervention group compared to the control group, while no changes were observed for musculoskeletal pain/discomfort. No significant intervention effects were found for the anthropometrics measures and blood pressure. Height-adjustable desks and pedagogical strategies to reduce/break-up sitting can positively modify classroom sitting patterns in children. Longer interventions, larger and varied sample size may be needed to show health impacts; however, these desks did not increase musculoskeletal pain/discomfort.

The Impact Of Stand-biased Desks On After-school Physical Activity Behaviors In Children

“…Based on previous research (Aminian et al, 2015& Contardo et al, 2016, the following hypotheses are proposed:…”

“…In summary, when appropriately addressed by instructors and administrators, the school day and environment offer children the opportunity to engage in a meaningful amount of PA (Erwin et al, 2011). Furthermore, stand-biased desk use has been associated with improved levels of SB (Aminian et al, 2015;Clemes et al, 2015;Contardo et al, 2016), increased energy expenditure (Benden et al, 2011;Benden et al, 2014), a decrease in age-matched BMI percentile (Wendel et al, 2016), improved posture (Benden et al, 2013), and improved cognitive function (Dornhecker et al, 2015;Mehta et al, 2015). These benefits may have an even greater impact on children with poorer initial health outcomes, such as in children with obesity, who experienced a greater increase in energy expenditure over those of normal weight (Benden et al, 2014).…”

“…The use of a stand-biased desk has been found to result in less postural discomfort overall, however no significant differences have been found indicating less time is spent in nonpreferred postures during use, compared to students seated at traditional desks (Benden et al, 2013). As a result of stand-biased desk use, several studies measuring postural behaviors have also reported significant decreases in sitting time during the school day, with both standing and stepping times increasing as a result (Aminian et al, 2015;Clemes et al, 2015;Contardo et al, 2016). Koepp and colleagues (2016) similarly found that in-class step counts increased following one school-year of stand-biased desk exposure.…”

“…Although stepping time and step count measured by ActivPAL inclinometers and pedometry have been previously reported as objective measures of PA following stand-biased desk exposure (Aminian et al, 2015;Clemes et al, 2015;Contardo et al, 2016;Hinckson et al, 2013;& Koepp et al, 2012), these fail to capture the intensity of activity performed, instead quantifying time spent in motion. Furthermore, only one study has examined the after-school period for changes in PA and SB (Aminian et al, 2015), in which a small and insignificant increase in stepping time was found following 9-weeks of stand-biased desk use.…”

“…randomized pilot trial conducted in Australia byContardo et al (2016). Stand-biased desks were introduced into the classroom with the intention of reducing and breaking-up SB in students.Two 6 th grade classrooms (one intervention and one control) from a single elementary school (n=48; 24 participants per classroom) completed the study.…”