Cocaine normally stays in the system for approximately 48 hours. Although the method of administration and the dose administered affects how long it takes for the body to metabolize this drug. When coca leaves are chewed, absorption time is around 30 minutes.
The muscles that provide the movement for the shoulder and upper arm include the anterior muscles in the front, the posterior muscles in the back, and the shoulder muscles that are sort of in between. Pectoralis major: This muscle has two heads, or sections of muscle tissue, and covers much of the front of the thoracic cage.
The pectoralis muscles -- major and minor -- attach your ribs to the front of your upper arm. These muscles lift your arm forward, bring it in toward your body and rotate your shoulder inward. The coracobrachialis is a deep muscle on the front of your upper arm that moves your arm forward.