The effect of feedback training on lumbosacral compression during simulated occupational lifting

This study measured the effect of a feedback training program on lumbar compression during simulated occupational lifting. Two distinct types of feedback were compared: real-time electromyographic feedback, vs. an acceleration index delivered verbally post-lift. Kinematic data were collected from 28 subjects during symmetrical sagittal plane lifts. Following a baseline session, two feedback training sessions were provided, with a 1-week interval between each session. A control group followed the same protocols, but without receiving feedback training. A post-training session, using protocols identical to the baseline session, was used to assess pre-to-post changes in the dependent variable: peak lumbosacral compression computed using a dynamic linked-segment model. All three groups showed reductions in peak compression from pre-to-post: on average the control group improved by 11.2%, the EMG group by 16.7%, and the acceleration group by 25.3%. The results revealed an interaction between the improvement and the group (p=0.023), and a difference between the improvement in the control group and that in the verbal acceleration feedback group (p<0.01). These reductions in lumbosacral compression persisted after a 7-day interval without feedback training, suggesting that this approach could provide sustained risk-reduction during manual materials handling.