Anatomy

Anterior Deltoid Origin: Anterosuperior border of the lateral 1/3 of the clavicle. Insertion: Deltoid tuberosity of humerus on...

The deltoid does the smallest share of the work exactly where the lateral raise begins — and...

Posterior deltoid Origin: Inferior margin of spine of scapula. Insertion: Deltoid tuberosity of humerus. Action: Abduction, horizontal extension...