The rear delta raise, also known as the rear deltoid raise, or rear shoulder raise is an exercise in weight training. This exercise is an isolation exercise that heavily works the posterior deltoid muscle. The movement is primarily limited to the two shoulder joints: the glenohumeral joint and the scapulothoracic joint. Scapular movement will also cause movement in the sternoclavicular joint and acromioclavicular joint. If the elbow bends during the extension exercises, it gravitates into a rowing motion.