目的：探討5週核心訓練對青少年桌球運動員動態平衡、敏捷性及正手回擊球球速表現之影響。方法：招募30名13–17歲之桌球運動員為對象，參與者依性別與擊球球速配對分為核心訓練組及控制組 (每組各15人)。所有參與者每週進行6天的專項訓練，核心訓練組在上午的專項訓練結束後另進行持續時間30–40分鐘之漸進式核心訓練、每週3次、共進行5週；於5週訓練前、後皆進行星狀偏移平衡、T型敏捷及正手回擊球球速之測驗。所得數據以相依樣本t檢定及獨立樣本t檢定比較各依變項組內及組間之差異。結果：(1) 核心訓練組訓練後之非持拍側腳支撐的星狀偏移表現顯著優於訓練前 (p < .05)，而控制組則無顯著變化；此外，兩組持拍側腳支撐的星狀偏移表現則無顯著變化。(2) 核心訓練組訓練後之T型敏捷表現與訓練前無顯著差異，但控制組則顯著劣於訓練前 (p < .05)，且核心訓練組顯著優於控制組 (p < .05)。(3) 二組正手回擊球球速皆無顯著差異。結論：青少年桌球運動員進行每週3次、持續5週之漸進式核心訓練，能提升動態平衡表現、維持敏捷性，但無法提升正手回擊球球速。

Purpose: To investigate the effects of a 5-week core training program on dynamic balance, agility, and ball speed of forehand stroke in adolescent table tennis players. Methods: Thirty table tennis layers aged 13–17 were recruited and assigned to either a core training group or a control group (15 in each group), depending on their gender and ball speed of forehand stroke. All participants engaged in sport-specific training 6 days per week. In addition, the core training group performed a progressive core training program 3 times per week for 5 weeks, with each session lasting 30–40 minutes, conducted after their morning sport-specific training. Assessments of star excursion balance test (SEBT), T-test agility, and forehand stroke ball speed were conducted before and after the five-week training period. Data were analyzed using paired t-test and independent t-test to examine within- and between-group differences for each dependent variable. Results: (1) Following the intervention, the SEBT performance on the non-racket side’s supporting leg in the core training group improved significantly (p < .05), whereas no significant difference was observed in the control group. Additionally, there were no significant differences in the SEBT performance on the racket-side supporting leg in either group. (2) There was no significant change in T-test agility performance in the core training group after the intervention. However, the control group demonstrated a significant decline compared to pre-training levels (p < .05). Furthermore, the core training group performed significantly better than the control group after training (p < .05). (3) No significant differences were found in ball speed of forehand stroke in either group. Conclusion: A 5-week progressive core training program conducted 3 times per week improved dynamic balance and helped maintain agility in adolescent table tennis athletes. However, it cannot increase the ball speed of forehand stroke.