what is the deltoid muscle used for
The deltoid muscle is used in all side lifting movements and any movement of the humerus on the scapula. It is divided into three portions, anterior, middle and posterior, with the fibres having different roles due to their orientation.he deltoid muscle is used in all side lifting movements and any movement of the humerus on the scapula. It is divided into three portions, anterior, middle and posterior, with the fibres having different roles due to their orientation.