A comparative study on the recruitment of shoulder stabilizing muscles and types of exercises

Abstract

The shoulder is susceptible to disturbances caused by microtraumas due to direct contact of the surrounding skeletal structures or failure of the soft parts of the rotator cuff and other muscles inserted into the gle-nohumeral joint. The purpose of the study was to compare the electro-myographic signal in the stabilizing muscles of the shoulder during the diagonal elevation exercise as recommended by the proprioceptive neuromuscular facilitation (PNF) method and dumbbell exercise. This study is classified as Quase-experiment. Subjects were instructed to perform diagonal standard exercises and the electromyographic signal was detected from pectoralis muscles, middle and upper trapezius of dominant limb in each subject. We observed greater muscular recruit-ment when the PNF method was adopted in comparison with the dumbbell workouts for the trapezius upper and middle fiber muscles and for the major pectoralis (267,30 μv/181,02 μv; 235,76 μv/;164,47 μv; 299,87 μv/148,69 μv; P < 0.001). The PNF method promotes a greater re-cruitment of the shoulder dynamic stabilizing muscles during diagonal elevation exercises. Being so, such kinesiotherapeutic technique may be effectively used in the prevention, treatment and rehabilitation of shoulder disorders.