Isokinetic strength relationships in shoulder muscles

The purpose of this study was to extend and refine former findings which related to strength characteristics of the major muscle groups operating on the glenohumeral joint. Based on preliminary isokinetic evaluation of five women and five men, which indicated that overall dominance was not associated with significantly stronger muscles, the dominant shoulders of 30 normal non-athletic subjects, 15 women and 15 men, were tested concentrically and eccentrically, at 60, 120 and 180 °/s. The descending order of muscle strength at both contraction modes and for both genders was: extensors, adductors, flexors, abductors, internal rotators and external rotators. Inter-muscle groupsʹ strength correlation coefficients have indicated significant, moderate-fairly strong, relationships in men but not in women. The implications of these findings in terms of testing and shoulder muscle conditioning are discussed.