Article

OBJECTIVE: To compare the electrophysiological activity in submandibular
hyolaryngeal muscles during performance of 2 exercises that incorporate
resistance against muscular contraction. DESIGN: Within-subject repeated-measures
design. SETTING: Academic research laboratory. PARTICIPANTS: Healthy, young adult
women (N=26; mean age, 24.1y) without a history of dysphagia, cervical spine
conditions, neurologic disease, or head/neck cancer. INTERVENTIONS: Participants
performed 2 isometric exercises requiring contraction against resistance to the
submandibular hyolaryngeal muscles: one requiring jaw opening against a semirigid
brace (chin-to-chest [CtC] exercise) and one requiring a chin tuck against an
air-inflated rubber ball (chin tuck against resistance [CTAR] exercise). Measures
of electrophysiology using surface electromyography (sEMG) were obtained during
exercise performance. MAIN OUTCOME MEASURES: Microvolts as measured from sEMG
electrode sensors placed on the skin surface above the hyolaryngeal muscles
(surface of skin above geniohyoid, mylohyoid, and anterior digastric). Dependent
variables included peak contraction amplitude (in muV) and mean contraction
amplitude (in muV) across 10 seconds of sustained contraction. RESULTS:
Significant effects of exercise on peak and mean contraction amplitudes were
present when both exercises were compared with baseline sEMG activity. (P<.001
for both). Normalized values of peak contraction amplitude and mean contraction
amplitude during performance of CtC were not significantly different compared
with CTAR. CONCLUSIONS:
This study provides supporting evidence for the influence
of 2 published exercises on motor unit recruitment in the submandibular
hyolaryngeal muscles, both of which have been previously proposed as
rehabilitative modalities. Theoretical and clinical implications are discussed.
CI - Copyright (c) 2016 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS