Impact of vehicle seat back inclination on occupational driving safety

Document Type : Research Paper


1 Nicholls State University, Thibodaux, LA, USA

2 Louisiana State University, Louisiana, USA


This study determined effect of automobile seat backrest inclination on lattisimus dorsi muscle electromyographic (EMG) activity. Myoelectric activity was determined at two seat backrest angles (90 degrees and 100 degrees inclinations).  Twenty-one (21) participants were engaged in the study. Electromygraphic activity at 90 degrees inclination had slope value of -0.065 mV/minute while 100 degrees had slope value -0.044 mV/minute. Myoelectric data indicated activity at 100 degrees was lesser than at 90 degrees for latissimus dorsi muscles. Results of the experiment were significant (P=0.01). Myoelectric results indicated that activity of the latissimus dorsi muscles decreased with increase in backrest angle.


Main Subjects

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