Electromyography and office-chair design; a pilot study

A pilot study is described which investigates the feasibility of using spinal electromyography as a means of discriminating between the effects of various office-chair designs on spinal muscle activity. The results support the view that the use of a backrest reduces spinal muscle activity but also suggest that when working (typing), the technique adopted by the worker has a greater effect on muscle activity than the design of the chair. Simple electromyographic studies may not be sufficiently sensitive to discriminate between the effects of individual chairs on spinal health, but it is suggested that ergonomic considerations may be more important than individual design concepts of office chairs.