Seated buttock contours: a pilot study of Australian senior high-school students

Both posture and comfort of a chair are influenced by the contour and characteristics of the seat. Knowledge of seat contours of a student population could thus be useful in the design of school chairs. This study investigated seated buttock contours of senior high-school students in order to determine: (a) their general characteristics, (b) the effect of gender and sitting posture and (c) the relationship between the contours and selected anthropometric variables (stature and mass). A contour measurement device was developed and used to measure buttock contours in five sitting postures (typing, sitting up, sitting back, slumping and writing). Buttock contours were quantified by constructing anterior-posterior (AP) and lateral profiles from which six discrete profile dimension measurements were made. AP and lateral profiles were found to have a consistent shape across all participants. Five out of six profile dimensions were significantly different between genders, with just one significantly different between sitting postures (typing and sitting back). Correlations between anthropometric measures and profile dimensions were relatively low (r < 0.34) with no clear patterns evident. Overall results of this study suggest that buttock contours are influenced by gender to a greater extent than sitting posture.