Relationship Between Scapular Position During Maximum Voluntary Isometric Contraction Of Shoulder Flexion and Scapular Position During Baseball Pitching

• Published in: Japanese Journal of Sports Physical Therapy Vol. 3; no. 1; pp. 6 - 12
• Main Authors: Saizaki, Kazuya, Toda, Hajime, Yoshida, Makoto, Nomura, Yuki, Yamamoto, Keizo, Yamashita, Hirokatsu, Kodesho, Taiki, Asano, Shu, Iida, Naoya, Yoshida, Masahiro, Katayose, Masaki, Watanabe, Shun
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Sports Physical Therapy 2025; 一般社団法人 日本スポーツ理学療法学会
• Subjects: baseball; pitching motion; scapular motion; shoulder joint; throwing shoulder injury; 投球動作; 投球障害肩; 肩甲骨運動; 肩関節; 野球
• ISSN: 2758-4356
• DOI: 10.57495/jjspt.3.1_6

Objective: This study aimed to investigate the between scapular position during maximal isometric shoulder flexion and scapular position during baseball pitching.Methods: We recruited fifteen collegiate baseball players and used an optical motion tracking system to assess scapular position. The scapula position during maximal isometric shoulder flexion was defined as the amount of change in the scapular internal rotation, downward rotation, and anterior tilt angle from the time of resting position to the time of maximum muscle exertion. We assessed scapular position at foot contact (FC), maximum shoulder external rotation (MER), and ball release of pitching motion.Results: The amount of change in the scapular internal rotation angle during maximal isometric shoulder flexion had a significant relationship with the scapular internal rotation angle at FC (r＝0.55, p＝0.033) and MER (r＝0.52, p＝0.047).Conclusion: This finding suggest that the evaluation of amount of change in the scapular internal rotation angle during maximal isometric shoulder flexion can be a useful screening method to predict excessive scapular internal rotation at FC and MER of pitching.