Biopsychosocial Influence on Shoulder Pain

Long-acting propranolol (Propranolol LA) 60 mg to be administered orally daily for Days 1 (before exercise induced muscle injury) and Days 2-4 following exercise induced muscle injury.

Placebo capsules will be prepared by the University of Florida Investigational Drug Service to be visually indistinguishable from the active medication and delivered orally. Placebo administration will be done in the same fashion as propranolol - administered on Days 1 (before exercise induced muscle injury) and the Days 2-4 after the exercise induced muscle injury.

Shoulder anatomy education modules will be administered Days 2-4 (after exercised induced muscle injury) following exercise enhance injury with the goal of participant understanding shoulder anatomy and injury while reviewing: a) structure and arthrokinematics of the shoulder joint; b) muscle anatomy of the shoulder with emphasis on the rotator cuff; and c) potential shoulder pain generators from the exercise-induced injury. This education component will be devoid of information related to pain signaling and cognitive restructuring that characterizes Pain Processing Education modules. These education modules will be scripted and structured so they are provided in a standardized manner for all subjects.

Pain processing education modules will be administered Days 2-4 (after exercised induced muscle injury) following exercise enhance injury with the goal of better understanding of pain processing and psycho-education. This information will encourage shoulder activation by: a) reducing the threat of muscle injury; b) encouraging normal use of the shoulder and arm; and c) addressing specific concerns expressed by the subject (e.g. pain with shoulder motion is a sign of re-injury). This education component will be devoid of detailed information on shoulder anatomy, movement, and injury that characterizes the Shoulder Anatomy Education modules. These education modules will be scripted and structured so they are provided in a standardized manner for all subjects.