Neuromuscular Activity of Trunk Muscles during Side Plank Exercise and an Additional Motoric-Task Perturbation

Abstract

Problem: Core-specific sensorimotor exercises (CSSE) combined with technically applied unexpected high-intensity perturbations (UHIP) are able to enhance neuromuscular activity of the trunk muscles (TM). SinceincludingUHIP into clinical practice is complicated, it is warranted to implement a feasible perturbation task. Aim of the study was to analyze the effects of an additional motoric-task perturbation on trunk neuromuscular activation pattern during CSSE exercise. Methods: Ten participants (5m/5f; 29±2years; 177±7cm, 74±12kg) were included and prepared with a surface EMG-setup for trunk muscles. EMG-data were collected during a side plank on stable surface (SP; 30sec) and randomly in 3 different conditions: adding a pad under the right elbow (SPP), adding a perturbation task (SP+P) and adding pad and perturbation task (SPP+P). Root mean square (RMS) was calculated for the whole exercise cycle (30sec) and normalized to MVIC (%MVIC). Muscles were grouped to ventral (VR; VL) and dorsal (DR; DL) right/left. In addition, the ratios of Ventral: Dorsal (V: D) and Side-Right: Side-Left (SR: SL) were calculated. Differences between conditions were assessed for muscle groups and ratios (repeated-measures ANOVA; α=0.05). Results: SPP+P showed the highest EMG-RMS for all muscles except DL, showing significant differences between conditions SP and SP+P in VR and VL,respectively. No differences (p<0.05) were found between SPP and SPP+P, SP+P. Ratios revealedno significant differences between conditions. Discussion: The additional motoric-task perturbation during a CSSE significantly enhanced trunk neuromuscular activity.