title: The effects of concentric versus eccentric isokinetic strength training of the rotator cuff in the plane of the scapula at various speeds.
abstract: This study compares the effects of three modes of isokinetic resistance training at the shoulder--concentric, eccentric, and a combination of both concentric and eccentric, with a group that received no training at all. Twenty-eight healthy volunteers (male and females), 18 to 36 years of age, with no history of shoulder pathology, were randomly assigned to one of four groups; concentric training, eccentric training, a combination of both concentric and eccentric training, or control (no training). Testing and training of the dominant shoulder was performed on an isokinetic dynamometer. All subjects were pretested and post-tested both concentrically and eccentrically for humeral internal/external rotation and abduction at speeds of 60 degrees/sec and 120 degrees/sec. Each training session consisted of a total of twelve sets of ten maximal repetitions, and was repeated three times a week for four weeks. The absolute and percent difference in peak force and peak torque for each group between the pretest and post-test was calculated for each combination of position, mode, and speed. A significant difference between the concentric/eccentric group and the eccentric group was found for abduction (p < 0.05). The eccentric group showed a significantly greater increase from the pretest to post-test for absolute differences in peak force and peak torque compared to the concentric/eccentric group (p < 0.05).
authors.affiliation: Department of Orthopaedic Surgery, University of Southern California School of Medicine, Los Angeles 90033, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Bast
authors.forename: C T
authors.initials: CT
authors.lastname: Vangsness
authors.forename: J
authors.initials: J
authors.lastname: Takemura
authors.forename: E
authors.initials: E
authors.lastname: Folkins
authors.forename: R
authors.initials: R
authors.lastname: Landel
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D007551:Isotonic Contraction / Q000502:physiology*; D008297:Male; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation; D017006:Rotator Cuff / Q000502:physiology*; D012540:Scapula / Q000502:physiology*; D012785:Shoulder Joint / Q000502:physiology*; D013997:Time Factors; D019415:Torque; D014891:Weight Lifting