肩關節的疼痛及傷害常發見於過肩運動之運動員，過肩運動包括單側或雙側的運動模式，如棒球、游泳、網球。部分研究曾測試過肩運動者的肩關節活動度進行測試，但未曾在單側或雙側的運動模式，如棒球、游泳、網球選手，之間作比較。因此，本研究的目的是比較健康的游泳，網球和棒球選手的肩關節活動角度及柔軟度。本次實驗受測者共27名（7游泳、11網球、9棒球）測量運動員肩彎曲、過度伸展、肩內轉/外轉，使用關節量角器進行測量，統計數據以單因子變異數分析及Turkey事後分析比較游泳、棒球、網球三項過肩性運動之肩關節活動度差異。結果發現在慣用手和非慣用手的肩彎曲及過度伸展，並沒有顯著的差異。游泳選手在肩內轉明顯大於網球和棒球運動員；肩外轉的結果顯示游泳選手顯著小於在網球和棒球運動員。在非慣用手部分，結果顯示網球選手在內轉角度部分明顯小於游泳和棒球運動員；在非慣用手肩外轉的部分三者無顯著差異。

Shoulder pain or pathology was a common injury in overhead athletes. Overhead sports included unilateral or bilateral arms used, like baseball, tennis, or swim. Although these sports have different characteristics, they show similar overhead movement patterns. However, few studies have been conducted with athletes who share this similar overhead movement but differ in unilateral or bilateral arms used, such as swimmers, baseball or tennis players. Therefore, the purpose of this study was to measure and compare the shoulder range of motion (ROM) in healthy swimmers, tennis and baseball players. Twenty-seven overhead athletes participated in this study (7 swimmers, 11 tennis players, and 9 baseball players). The shoulder flexion, hyperextension, internal or external rotation were measured by using goniometer for both arms. One-way ANOVA and Turkey post hoc comparisons were used to analyze the difference in dominant and non-dominant shoulder amongst swimmers, tennis, and baseball players. In dominant and non-dominant shoulder, no significantly difference was found in shoulder flexion and hyperextension amongst 3 groups. The internal rotation of dominant shoulder was significantly greater in swimmers than tennis and baseball players. The external rotation of dominant shoulder was showed significant smaller in swimmers than tennis and baseball players. In non-dominant shoulder, the internal rotation ROM was showed significantly smaller in tennis players than swimmers and baseball players. There was no significantly difference in external rotation ROM of non-dominant shoulder amongst three overhead sports.