A 2-kg medicine ball was covered in magnesium carbonate (gymnastics chalk) to leave a clear print on the floor after each throw so that the throwing distance could be easily determined. We placed a 10-m tape on the floor with the end fixed to the wall.

Participants performed 3 submaximal familiarization trials to ensure they understood the procedure, followed by 3 test trials. ” At the end of the instructions, the assessor warned about compensatory movements, such as side bending, tilting, or rotating the trunk. Then, you keep your maximal strength for 5 seconds without moving the rest of your body. 36 We gave specific information about the ER and IR strength tests to be performed: “After bringing your arm in the correct starting position, we want you to gradually push against the device until you reach maximum strength. The forearm was positioned against the HHD 2 cm proximal to the ulnar styloid process on the dorsal (ER) or ventral (IR) forearm for the strength assessment. Participants were barefoot and instructed to stand up straight, with the nondominant hand on the back (L4–L5) and the foot opposite of the tested upper extremity placed forward ( Figure 2).

The SAC procedure started with oral instructions from the assessor (P.D.). Therefore, the primary purpose of our study was to evaluate the reliability and validity of the SAC. As far as we know, no research has been conducted on the reliability and validity of a self-assessment technique for evaluating RC isometric strength. Therefore, we developed a self-assessment technique, the Self-Assessment Corner (SAC), to simplify evaluation of shoulder ER and IR isometric strength and eliminate the examiner's influence on the procedure and test results.

9– 11 For example, whereas isokinetic testing is considered the criterion standard for strength evaluation, its implementation in facilities, such as courts, fitness centers, or gymnasiums, may be compromised because of the extensive equipment required. 5, 7 Although valid and reliable measurement techniques exist to assess shoulder rotational strength, 8– 10 some limitations may interfere with season-long evaluation (eg, tester strength variability, lack of stabilization, inconsistency among testing procedures, the need for a skilled assessor, and high costs). Clinical examination, such as RC strength and physical performance tests (PPTs), are part of this screening and must be reliable, sensitive, specific, inexpensive, easy to perform, and widely available.

Pat3 reliability and validity