Analysis of Body Movement Patterns and Subjective Discomfort Ratings in Long-Duration Sitting

Abstract

A laboratory study was conducted to evaluate the hypothesis that discomfort in long-duration sitting is associated with more frequent posture changes. Two nominally identical production automobile driver seats were obtained for testing and one was modified in ways that were expected to increase discomfort. Twenty-four men and women with a wide range of age and body size sat in each of the seats for one hour on two different days while watching videos and completing a discomfort questionnaire every five minutes. Posture was monitored using a video, pressure sensors in the seats, and a Microsoft Kinect depth sensor. A variety of posture change metrics were computed from each data source. The modified seat produced significantly higher discomfort ratings. However, no difference in movement frequency was observed between the seats, and no relationship between maximum discomfort and movement frequency was observed.