Effects of adjustable sit-stand VDT workstations on workers' musculoskeletal discomfort, alertness and performance.
Adjustable sit-stand workstations, which are designed to allow workers to sit and stand autonomously while working, were examined to identify the effects on workers' musculoskeletal discomfort, alertness and performance. Twenty-four healthy subjects participated in the study. The subjects were required to do an English transcription task for 150 min under the following conditions: 1) sitting at standard workstations (Standard), 2) sitting on a chair with the work surface elevated to standing position (High-chair) and 3) a combination of 10-min sitting and 5-min standing with the same setting as that in the high-chair condition (Sit-stand). The subjective musculoskeletal discomfort scores indicated that High-chair and Sit-stand resulted in relatively higher discomfort levels than the Standard condition. Although the ratio between low-frequency (0.04-0.15 Hz) and high-frequency (0.15-0.4 Hz) components of heart rate variability (LF/HF ratio) in Sit-stand was higher than that in other conditions, there were no significant differences in subjective sleepiness among the three conditions. As for work performance, there was a tendency to be steadily high under the Sit-stand condition compared with other conditions, but not a significant difference. This study revealed that although the use of sit-stand workstations can contribute to keeping workers' arousal level steady, it has an adverse effect in light of musculoskeletal discomfort.
Nagoya City University Graduate School of Medical Sciences, Nagoya 467-8601, Japan.
Takeshi
T
Ebara
Tomohide
T
Kubo
Tatsuki
T
Inoue
Gen-i
GI
Murasaki
Hidemaro
H
Takeyama
Tomoaki
T
Sato
Hatsuko
H
Suzumura
Sayuri
S
Niwa
Toshimasa
T
Takanishi
Norihide
N
Tachi
Toru
T
Itani
D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D006804:Ergonomics; D005260:Female; D006801:Humans; D007374:Interior Design and Furnishings; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000517:prevention & control*; D011187:Posture / Q000502:physiology; D055815:Young Adult