The goal of this clinical trial is to test normal participants.

The main question it aims to answer is:

• Do the participant's pectoralis minor muscles change length immediately after performing an exercise that recruits the scapular retractor muscles? Participants will have their pectoralis minor muscle measured, then perform an exercise recruiting the scapular retractor muscles, and then have their pectoralis muscle measured again.

The participants will have their standing height measured in centimeters with a tape measure fixed against a wall. Participants will then step away from the wall and will be asked to stand in their normal resting position. A mark will be placed on the most medial-inferior aspect of the coracoid process and a second mark on the anterior-inferior edge of the third rib, one index finger's width lateral to the sternum. A caliper will then be used to measure the distance between these marks as the participant holds a normal exhalation.

Participants will then lay prone on a treatment plinth with a small towel roll under their forehead. The participants will form both fists and place them on the plinth just superior to their head, with bilateral thumbs up and the ulnar side of the hands resting on the plinth, and their arms relaxed so their elbows remain on the plinth. The participants will then lift their elbows off the plinth as high as possible while keeping their hands on the plinth. The participants will repeat this motion for 10 repetitions, performing three sets of this exercise with 30 seconds of rest in between each set.

After the third set, the participants will stand up and a second caliper will be used to once again measure PM length by the same tester using the same marks. This will conclude the testing procedure and the participant's involvement in the study.

Inclusion Criteria:

• 18 years of age or older. At least 130 degrees of shoulder elevation. None of the exclusion criteria.

Exclusion Criteria:

• Current shoulder pathology and or pain, prior shoulder surgery, any neurological impairment, any upper quarter deformity, a fracture of the upper extremity, or systemic inflammatory disease.