Chronic low back pain (LBP) is globally recognised as a leading cause of disability, with a global point-prevalence of 540 million people experiencing ‘activity-limiting’ LBP. A lack of muscle endurance is common in people with LBP, however the mechanisms underlying reduced endurance remain unclear. This study utilised high-density EMG (HDEMG) to evaluate differences in the spatial distribution and redistribution of lumbar erector spinae (ES) activity during an endurance task. Thirteen control (Age:26.46±5.0, 7 Males) and 13 LBP participants (Age:27.39±9.7, 6 Males) were recruited and HDEMG signals were detected from ES unilaterally using a 13×5 electrode grid adhered 2cm lateral to the L5 spinous process. Participants were asked to complete an isometric endurance task until failure (>10° trunk deviation) with muscle activity simultaneously recorded. The activity was computed to form a map of the EMG amplitude distribution and the position of the centre of activity (centroid) was monitored throughout the task.Introduction
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