Effects of Speed and Position on Dynamic Shoulder Strength

• Main Authors: I-Chun Huang, 黃宜君
• Other Authors: Fong-Chin Su
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/77977045780974641598

碩士 === 國立成功大學 === 醫學工程研究所 === 88 === The purpose of this study was to determine the effects of speed, test plane, and humerus position on peak torque values produced by shoulder elevators, depressors, internal and external rotators during concentric and eccentric contraction in young and healthy adults. Absolute peak torque value was calculated by multiplying the maximal force of constant velocity phase by the perpendicular distance from the axis of rotation to the pad. The constant velocity phase was defined the period with the speed between 90% and 110% of the testing velocity. 120 healthy subjects (60 males and 60 females) between the ages of 20 and 30 years were tested. The mean peak torque values of their shoulders were measured at speeds of 0o, 30o, 60o, 90o, 120o, 150o, 180o, 210o, and 240o per second for dominant side using a Kin-Com robotic dynamometer (Chattanooga Corp., Chattanooga, TN). MANOVA was used to analyze whether the shoulder strength was different in the different positions, humerus positions, and testing speeds. Tukey tests were adopted for post hoc analysis in the event that significant interaction effects occurred. The probability level of 0.05 was used through the study. Speed, testing plane, and humerus position had all significant influence on the shoulder strength. As speed increased, torque value decreased during eccentric contraction and increased during concentric contraction. Shoulder performed different strength with testing plane and humerus position changed. Cross-interaction between testing plane and humerus position was significant in the eccentric contraction for both elevation and depression. No statistical significance found in the concentric contraction. The study may help clinicians plan and rehabilitate shoulder injury patients.