The effectiveness of static stretching on various parameters such as range of motion or pain is studied and proved in literature. Static stretching in cross body position was also found helpful for improving shoulder range of motion with some disadvantages. In modified cross body position, the patient is positioned in a more advantageous way for him/her. Usually this stretching is done as active-assistive static stretching with the physiotherapist. Proof is still needed for the effectiveness of active-assistive static stretching in modified cross body position. Furthermore, there is no research about the effect of isolytic stretching which is relatively new technique compare to static stretches in subacromial impingement syndrome. In isolytic stretching, when the patient contracts the agonist muscle group with 20% muscle force active-assistive streching in agonist muscle group by the physiotherapist at the same time is done for 2-4 seconds. A fast isolytic stretching is applied in order to break the fibrous tissue. Our purpose is to investigate and compare the effect of isolytic and static stretching training in individuals having subacromial impingement syndrome with glenohumeral internal rotation deficit . Stretching groups will receive either isolytic or static stretching in modified cross body stretching position and standard physiotherapy program. There is a control group. Control group will receive only standard physiotherapy program. Standard physiotherapy program includes TENS, hotpack, posture and strengthening training program. Treatment program will last four times a week (4-4-4-3) for four weeks, 15 sessions in total.