The main stability of the shoulder should be provided by the four muscles called rotator cuff: supraspinatus, infraspinatus, teres minor and subscapularis. It is extremely important to do a regular strength training of the rotator cuff – both external and internal rotation, with more emphasis on the external rotation.

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The primary muscles worked during dumbbell scaption are the deltoids. In particular, the anterior and lateral deltoids. These are your front and side shoulder muscles.