Shoulder muscle EMG and resisting moment during diagonal exercise movements resisted by weight-and-pulley-circuit.

The aim of the study was to investigate which muscles contract (and to what extent) during diagonal shoulder movements resisted by a weight-and-pulley-circuit and the relationship between the calculated resisting moment of force and the maximum voluntary isometrical muscular moment. EMG, mechanical calculations and measurements of moments of force were used. With the resistance used in the study, flexion-abduction-external rotation (FLABER) highly activated all three parts of the deltoideus muscle and the infraspinatus. Flexion-adduction-external rotation (FLADER) highly activated the anterior and middle parts of the deltoideus, infraspinatus and moderately the sternocostal part of the pectoralis major. Extension-abduction-internal rotation (EXABIR) highly activated the posterior deltoideus and moderately the latissimus dorsi. Extension-adduction-internal rotation (EXADIR) highly activated the sternocostal part of the pectoralis major.