The effects of different pause types on neck and shoulder EMG activity during VDU work

Surface electromyographic recordings on the right side from the descending part of the trapezius muscle and from the levator scapulae muscle and discomfort ratings were assessed for twelve female word processor operators. The operators were studied during three work periods of 30 min each. Three different kinds of pauses, active pauses with pause gymnastic movements, passive pauses with rest and diverting pauses, were introduced into the work every six minutes. The static muscular load was low and about the same for the three work periods. High contraction levels with a duration of at least 1% of the registration time differed significantly between the three types of pauses, reflecting the activity during the pauses itself. Active pauses could thus change the muscle activity pattern. There was a tendency to prefer pauses with activity to passive pauses.