Author(s): TING, Y.L., LI, H., HUNG, W., CHEN, K., WU, Z., Institution: NATIONAL TAIWAN UNIVERSITY OF SPORT, Country: TAIWAN, Abstract-ID: 2132

INTRODUCTION:
Dynamic Neuromuscular Stabilization (DNS) is the neuromuscular therapy that can activate the primary motor cortex, sensorimotor cortex, and supplementary motor area of the cerebral cortex by resetting and correcting the balance of body tension and the function of the physiological system. It improves the motor control of strength and endurance and the athletic ability, thereby preventing sports injury and constructing the learning pattern of movements and sports. High-density electromyography (HD-EMG) is a non-invasive method with multiple electrodes to analyze neuromuscular conditions by amplitude map, centroid of gravity (COG), motor unit size (MU), motor unit conduction velocity (CV), and so on. Therefore, we design the present study to investigate the neuromuscular recruitment of the intervention of DNS with HD-EMG.
METHODS:
13 volunteers aged 20 to 30 years old were recruited in the present study. The HD-EMG signals of vastus lateralis obliquus (VLO), vastus medialis obliquus (VMO), semimembranosus (SM), and biceps femoris (BF) were collected prior and post-training through the OTBioLab system while performing plank position on the mat or a Redcord Trainer (sling), respectively. The movement of DNS training protocol was composed of Supine, Side-lying, Side lying with forearm support, Side lying with hand support, Side-lying to quadruped transition, Quadruped, Tripod and High kneeling reverse.
RESULTS:
The MU of VMO, VLO, SM and BF increased after the DNS training while performing plank, either on mat or sling. The MU of VMO and VLO were activated more while performing a plank on mat (△VMO: 4, △VLO: 4) than on the sling (△VMO: 3, △VLO: 2). On the contrary, the MU of SM and BF were activated more while performing plank on sling (△SM: 11, △BF: 8) than on mat (△SM: 4, △BF: 3). The COG of VMO, VLO, SM and BF shifted proximally after performing the training task. The COG of VMO shifted proximally especially performing plank on sling. The COG of VLO and BF was scattered that one shifted distally while performing plank on mat and the other shifted proximally, respectively. Rather special that the COG of SM shifted distally while performing plank on mat. The CV of VMO and VLO both increased after performing the training task while performing plank, either on mat (△VMO: 21 m/s, △VLO: 130 m/s) or sling (△VMO: 380 m/s, △VLO: 19 m/s). The CV of SM and BF increased only when performing plank on sling (△SM: 109 m/s, △BF: 656 m/s).
CONCLUSION:
Results of the present study indicated that after the intervention of DNS, more MU were activated, the COG were shifted proximally and the CV within motor unit would altered on the lower limb muscles. These findings provide solide evidence that that the neuromuscular recruitment pattern can be altered after training through DNS technique.

Reference:
1) Frank et al., Int J Sports Phys Ther., 2013
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3) Farina et al., J Electromyogr Kinesiol., 2008