抄録
The aim of this study was to investigate the changes of shoulder range of motions after 80 fastball pitches in elementary school pitchers. We studied 10 elementary school baseball pitchers. Shoulder internal rotation and external rotation with the arm abducted 90° (2nd IR and ER), internal rotation with the arm flexed 90° (3rd IR), gleno-humeral abduction(Abd) and horizontal flexion(HF) were measured bilaterally at three points of time, before pitching, immediately after 80 fastball pitches and on the day after pitching. At the 3 points, there were no significant differences between the dominant and non-dominant shoulders in 2nd IR, 2nd ER, 3rd IR, HF and Abd, except in HF on the next day of pitching. These good conditionings could be produced by continuous feedback of medical check-up. Between the 3 points of time, there were no significant difference in 2nd IR, 2nd ER, 3rd IR, HF and Abd. These results could be caused by the small number of subjects, youthfulness, good conditioning of the players and the practice pitch.
