探討女子排球舉臂動作對跳躍式發球表現的影響

Abstract

前言:隨著排球新規定「得球得分」的制訂，發球失誤的結果，由先前的僅是喪失發球權，變成直接失分，因此排球發球技術更成為各國注重的訓練技術之一。近年研究指出跳躍飄浮發球穩定性較佳於跳躍發球，成為現今主要發球方式，但目前少有關於跳躍飄浮發球技術與發球成效分析的相關文獻。目的：探討排球不同舉臂動作對跳躍式發球表現的影響。方法：以大專公開一級女子組之現役18位排球選手，其中以慣用直接舉臂及慣用擺臂後舉臂跳躍飄浮發球各7位，慣用跳躍發球4位，每位發10次成功發球，並以高速攝影機拍攝發球過程。兩種不同舉臂跳躍飄浮發球的成功率以獨立樣本t考驗進行分析；發球擊球高度、球飛行過網高度及落地角度，以混合設計二因子變異數分析，檢驗兩種不同舉臂發球型態與發球結果的影響。跳躍發球人數太少，所整理之數據僅以描述統計呈現參考。結果:不同發球型態間的成功率未達顯著差異；在發球表現的比較，跳躍飄浮擺臂發球的擊球高度顯著高於跳躍飄浮舉臂發球，其餘皆未達顯著差異。結論:在不同舉臂方式的跳躍飄浮發球表現，除了在擊球高度上有顯著差異外，在成功率及其他發球表現均未發現有顯著差異。未來可就擊球角度或是擊球位置進行探討，並以學習兩種舉臂動作後，以組內設計的方式比較兩種不同舉臂方式是否會有差異。Introduction: After the implementation of the rally-point scoring system, fault in serve will result in opponent’s score instead of just losing the right to serve and hence the technique of serve has been emphasized. Recent research has pointed out that jump float serve is more consistent than jump topspin serve, and hence has become main type of serve. However, there has been limited literature on analysis of the technique and the effect of jump float serve. Objective: To investigate the effect of various arm-cocking motions on the performance of jumping serves. Method: Eighteen female volleyball athletes from Division A1 University League participated in the study. Seven athletes have demonstrated consistent direct arm-cocking for jump float serve, seven athletes have arm-cocking after backward arm-swing for jump float serve, while other four athletes have jump topspin serve. Each participant completed 10 successful serves, recorded with High-speed cameras. The serve percentage of both arm-cocking motion for jump float serve was analyzed with independent t-test. The height of hand-ball contact, height of the serve crossing the top of the net and landing angle were analyzed with mixed-design 2-way ANOVAs to investigate the effect of both types of arm-cocking motion. The samples of jump topspin serve was not sufficient to be analyzed, it would only be presented as descriptive statistics. Results: There was no significant difference on the type of arm-cocking motion on serve percentage. On the performances of the serve, only the height of contact had significant difference between the two types of arm-cocking motion, other performances did not reach significant level. Conclusion: Only the height of contact has shown to be significantly affected by different arm-cocking motions in jump float serve. Serve percentage and other performance variables did not show significant difference between the two types of arm-cocking motion. The angle and/or the position of ball-hand contact could be further investigated in future study. The effect of the arm-cocking motion could be further understood with a within-group design where the participants learn to perform both arm-cocking motions.