This course describes shoulder internal rotator release and lengthening (commonly referred to as shoulder mobility, shoulder mobility exercises, overhead mobility, shoulder internal rotator foam rolling, shoulder internal rotator release with ball, and/or shoulder stretching). Although terms like tight muscle, shoulder muscle tightness, rotator cuff tightness, tight lats, and tight pecs are commonly used, it may be more accurate to label these muscles as prone to over-activity (e.g. hypertonic, phasic), which may result in poor shoulder mobility. Performing shoulder internal rotator release and lengthening techniques to increase mobility prior to activation, integration, and strengthening techniques may significantly enhance rehabilitation and performance programs.