This study will compare two exercise programs in an interventional study for manual wheelchair users with spinal cord injury and shoulder pain. Subjects without spinal cord injury will also be enrolled to compare exercise approaches.

The investigators hypothesis is that the biomechanically based exercise program will demonstrate greater muscle activation of targeted muscles, and reduced compression risk to the rotator cuff tendons.

Inclusion Criteria:

1. Persons with paraplegia at least 1 year post SCI. Prior to this time patients are still adjusting to independent function with manual wheelchairs as their primary means of mobility. This criteria ensures the subjects have had sufficient exposure to the functional demands associated with their condition.
2. Age 21 to 60 years old; below age 21, particularly in males, the humeral growth plate may not have fully closed. Including subjects above this age ensures skeletal maturity. After age 60, even in able-bodied individuals, substantial degenerative changes can begin to occur in the shoulder joint.
3. Use of a manual wheelchair as the primary means of mobility (> 50% time). This is the population with most risk of development of shoulder pain and associated secondary complications.
4. A history of unilateral or bilateral shoulder pain that interferes with at least one functional task. Symptoms localized to the proximal anterior, lateral, or posterior glenohumeral (shoulder joint) region are required. Rotator cuff tendinopathy and "impingement" syndromes involve localized pain in this region. More diffuse symptoms are consistent with combined shoulder/neck syndromes or radiating pain from cervical spine pathology.

Exclusion Criteria:

1. Inability to provide informed consent.
2. Reproduction of shoulder pain, pain radiating down the upper extremity, numbness or tingling in the upper extremity, or other upper extremity symptoms during a cervical screening examination or thoracic outlet testing. This result would be indicative of primary cervical or thoracic outlet pathology.
3. Shoulder pain of traumatic origin. Cumulative trauma disorders are of primary interest and most amenable to the proposed exercise interventions.
4. History of shoulder surgery or dislocation.
5. Recent history of fracture (within 1 year), hospitalization (within the past month), or cortisone injection to the shoulder (within 4 months). These conditions may interfere with safe or effective completion of the exercise intervention.
6. A diagnosis or imaging findings of rheumatoid arthritis, end stage osteoarthritis, full thickness rotator cuff tear, adhesive capsulitis, or complex regional pain syndrome. These subjects may have joint disease progression that is severe, or not appropriately treated with a stretching and strengthening intervention.
7. Diagnosed major depression, alcohol or substance abuse, or other serious medical conditions. These conditions may prevent subjects from regularly completing the exercise intervention

All criteria apply to both groups excepting manual wheelchair use and SCI criteria not applicable to the able bodied subject group.