title: Effects of augmented trunk stabilization with external compression support on shoulder and scapular muscle activity and maximum strength during isometric shoulder abduction.
abstract: The aim of the present study was to investigate the effects of augmented trunk stabilization with external compression support (ECS) on the electromyography (EMG) activity of shoulder and scapular muscles and shoulder abductor strength during isometric shoulder abduction. Twenty-six women volunteered for the study. Surface EMG was used to monitor the activity of the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and middle deltoid (MD), and shoulder abductor strength was measured using a dynamometer during three experimental conditions: (1) no external support (condition-1), (2) pelvic support (condition-2), and (3) pelvic and thoracic supports (condition-3) in an active therapeutic movement device. EMG activities were significantly lower for UT and higher for MD during condition 3 than during condition 1 (p < 0.05). The MD/UT ratio was significantly higher during condition 3 than during conditions 1 and 2, and higher during condition 2 than during condition 1 (p < 0.05). Shoulder abductor strength was significantly higher during condition 3 than during condition 1 (p < 0.05). These findings suggest that augmented trunk stabilization with the ECS may be advantageous with regard to reducing the compensatory muscle effort of the UT during isometric shoulder abduction and increasing shoulder abductor strength.
authors.affiliation: Dept. of Physical Therapy, College of Natural Science, Daejeon University, 62 Daehak-ro, Dong-gu, Daejeon 300-716, Republic of Korea.
authors.forename: Hyun-jeong
authors.initials: HJ
authors.lastname: Jang
authors.affiliation: Dept. of Physical Therapy, College of Natural Science, Daejeon University, 62 Daehak-ro, Dong-gu, Daejeon 300-716, Republic of Korea.
authors.forename: Suhn-yeop
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Dept. of Physical Therapy, College of Health Science, Cheongju University, 298 Daesung-ro, Cheongwon-gu, Cheongju, Chungbuk 360-764, Republic of Korea. Electronic address: odduck@cju.ac.kr.
authors.forename: Duck-won
authors.initials: DW
authors.lastname: Oh
mesh_terms: D000293:Adolescent; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D009989:Orthotic Devices; D012540:Scapula / Q000502:physiology*; D012782:Shoulder / Q000502:physiology*; D012785:Shoulder Joint / Q000502:physiology; D060726:Torso / Q000502:physiology*; D055815:Young Adult
keywords: EMG activity; External compression support; Shoulder abduction; Strength; Trunk stabilization