Effect of two dynamic seat cushions on postural shift, trunk muscle activation and spinal discomfort in office workers
研究了两种不同充气程度的动态座垫对办公室工作人员姿势转移、躯干肌肉激活和脊柱不适的影响，发现一种座垫能增加姿势转移和腰部肌肉激活，两种座垫均能减轻脊柱不适。
We investigated the effect of two dynamic seat cushions on postural shift, trunk muscle activation and spinal discomfort. In this repeated-measures study, 30 healthy office workers were randomly assigned to a sequence of three conditions: sitting on a dynamic seat cushion-A, cushion-B and control (no seat cushion). The two dynamic seat cushions had different inflation levels. Participants typed a standard text for an hour and were monitored for postural shift by using a seat pressure mat, transversus abdominis/internal oblique and lumbar multifidus muscles activity by using surface EMG, spinal discomfort by using Borg's CR-10 scale. Two-way repeated ANOVAs showed no statistically significant interaction effects between condition and time on postural shift and muscle activation. Post hoc Bonferroni tests showed that postural shifts and lumbar multifidus activation during sitting on cushion-A were significantly higher (p < 0.01) than in the control and cushion-B conditions. Both cushions reduced spinal discomfort, compared to the control condition (p < 0.05).