Participants will be initially assessed for their suitability for inclusion in the study and will undergo a physical screening of the affected shoulder and cervical spine by an experienced physiotherapist. After, participants will be attended 72 hours after data recording of the baseline measures (range of motion with a goniometer, pressure pain threshold with a algometer, and peak force with a dynamometer) for four sessions per week with 24 hours of interval between sessions. At each experimental week session, each participant will receive one of the two treatment conditions (MWM or sham) and then will repeats the assessment. In the following week, there will be a crossover condition of each individual and 24 hours after the last treatment session, the examiner will do the last assessment.

Inclusion Criteria:

• history of shoulder pain of >1-week duration, localized at the proximal anterolateral shoulder region consistent to Shoulder Impingement Syndrome (SIS);
• at least 1 positive impingement test (Jobe's test, Neer's test, Hawkins-Kennedy's Test) associated with painful range of motion during arm elevation; or pain during external rotation with the arm in 90 degrees of elevation in the coronal plane.

Exclusion Criteria:

• fibromyalgia (based on self-report),pregnancy, a history of onset of symptoms because of traumatic injury, other histories of shoulder injury, torn tendons, ligamentous laxity based on positive Sulcus test and apprehension test, numbness or tingling in the upper extremity, previous shoulder or neck surgery, systemic illnesses, body mass index > 28kg/m2, corticosteroid injection 3 months before evaluation, physical therapy 3 months before evaluation.