OBJECTIVE: To investigate the relationship between backrest thickness and lumbar muscle fatigue so as to confirm the fitting backrest thickness. METHOD: Twenty subjects coming from university seated at a computer workstation in three backrest thicknesses: 4, 7 and 10 cm. The time that the subjects reported the lumbar muscle fatigue was collected during each trial and subjective appraise was collected at the end of the entire protocol. RESULTS: The MF value decreased and lumbar muscle felt fatigue in all three backrest thickness. Subject could feel fatigue more late [(45.0 +/- 10.8) min] and subject felt more comfort at 7 cm thickness. CONCLUSION: It is better to relive computer worker lumbar muscle fatigue when the backrest thickness was kept on 7 cm. Work break was needed because one hour work could cause muscle fatigue.
OBJECTIVE: To investigate the relationship between backrest thickness and lumbar muscle fatigue so as to confirm the fitting backrest thickness. METHOD: Twenty subjects coming from university seated at a computer workstation in three backrest thicknesses: 4, 7 and 10 cm. The time that the subjects reported the lumbar muscle fatigue was collected during each trial and subjective appraise was collected at the end of the entire protocol. RESULTS: The MF value decreased and lumbar muscle felt fatigue in all three backrest thickness. Subject could feel fatigue more late [(45.0 +/- 10.8) min] and subject felt more comfort at 7 cm thickness. CONCLUSION: It is better to relive computer worker lumbar muscle fatigue when the backrest thickness was kept on 7 cm. Work break was needed because one hour work could cause muscle fatigue.