Masaaki Tsuruike1, Todd S Ellenbecker. 1. Graduate Athletic Training Education Program, Department of Kinesiology, San José State University, CA;
Abstract
CONTEXT: Proper scapular function during humeral elevation, such as upward rotation, external rotation, and posterior tilting of the scapula, is necessary to prevent shoulder injury. However, the appropriate intensity of rehabilitation exercise for the periscapular muscles has yet to be clarified. OBJECTIVE: To identify the serratus anterior, lower trapezius, infraspinatus, and posterior deltoid muscle activities during 2 free-motion exercises using 3 intensities and to compare these muscle activities with isometric contractions during quadruped shoulder flexion and external rotation and abduction of the glenohumeral joint. DESIGN: Cross-sectional study. SETTING: Health Science Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 16 uninjured, healthy, active, male college students (age = 19.5 ± 1.2 years, height = 173.1 ± 6.5 cm, weight = 68.8 ± 6.6 kg). MAIN OUTCOME MEASURE(S): Mean electromyographic activity normalized by the maximal voluntary isometric contraction was analyzed across 3 intensities and 5 exercises. Intraclass correlation coefficients were calculated for electromyographic activity of the 4 muscles in each free-motion exercise. RESULTS: Significant interactions in electromyographic activity were observed between intensities and exercises (P < .05). The quadruped shoulder-flexion exercise activated all 4 muscles compared with other exercises. Also, the modified robbery free-motion exercise activated the serratus anterior, lower trapezius, and infraspinatus compared with the lawn-mower free-motion exercise. However, neither exercise showed a difference in posterior deltoid electromyographic activity. CONCLUSIONS: Three intensities exposed the nature of the periscapular muscle activities across the different exercises. The free-motion exercise in periscapular muscle rehabilitation may not modify serratus anterior, lower trapezius, and infraspinatus muscle activities unless knee-joint extension is limited.
CONTEXT: Proper scapular function during humeral elevation, such as upward rotation, external rotation, and posterior tilting of the scapula, is necessary to prevent shoulder injury. However, the appropriate intensity of rehabilitation exercise for the periscapular muscles has yet to be clarified. OBJECTIVE: To identify the serratus anterior, lower trapezius, infraspinatus, and posterior deltoid muscle activities during 2 free-motion exercises using 3 intensities and to compare these muscle activities with isometric contractions during quadruped shoulder flexion and external rotation and abduction of the glenohumeral joint. DESIGN: Cross-sectional study. SETTING: Health Science Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 16 uninjured, healthy, active, male college students (age = 19.5 ± 1.2 years, height = 173.1 ± 6.5 cm, weight = 68.8 ± 6.6 kg). MAIN OUTCOME MEASURE(S): Mean electromyographic activity normalized by the maximal voluntary isometric contraction was analyzed across 3 intensities and 5 exercises. Intraclass correlation coefficients were calculated for electromyographic activity of the 4 muscles in each free-motion exercise. RESULTS: Significant interactions in electromyographic activity were observed between intensities and exercises (P < .05). The quadruped shoulder-flexion exercise activated all 4 muscles compared with other exercises. Also, the modified robbery free-motion exercise activated the serratus anterior, lower trapezius, and infraspinatus compared with the lawn-mower free-motion exercise. However, neither exercise showed a difference in posterior deltoid electromyographic activity. CONCLUSIONS: Three intensities exposed the nature of the periscapular muscle activities across the different exercises. The free-motion exercise in periscapular muscle rehabilitation may not modify serratus anterior, lower trapezius, and infraspinatus muscle activities unless knee-joint extension is limited.
Authors: W Steven Tucker; Charles W Armstrong; Phillip A Gribble; Mark K Timmons; Richard A Yeasting Journal: Arch Phys Med Rehabil Date: 2010-04 Impact factor: 3.966
Authors: Ann M Cools; Vincent Dewitte; Frederick Lanszweert; Dries Notebaert; Arne Roets; Barbara Soetens; Barbara Cagnie; Erik E Witvrouw Journal: Am J Sports Med Date: 2007-07-02 Impact factor: 6.202
Authors: Eleanor Richardson; Jeremy S Lewis; Jo Gibson; Chris Morgan; Mark Halaki; Karen Ginn; Gillian Yeowell Journal: BMJ Open Sport Exerc Med Date: 2020-04-22
Authors: Benno Ejnisman; Gisele Barbosa; Carlos V Andreoli; A de Castro Pochini; Thiago Lobo; Rodrigo Zogaib; Moises Cohen; Mario Bizzini; Jiri Dvorak Journal: Open Access J Sports Med Date: 2016-08-08