The current study will teach the same 4 simple shoulder strengthening exercises performed in the prior study to patients with healthy shoulders. Half of the patients will receive 2 sessions of one-to-one training with a physical therapist, and the other half will receive 4 sessions of training combined with an interactive education program on techniques to protect their shoulder in a class format led by a physical therapist and a peer mentor with a spinal cord injury. Patients will be followed for 3 years to learn if they develop shoulder pain.