跆拳道是一種主要以手部的擊打與腳部的踢踹進行對抗的技擊運動。由於跆拳道高度肢體碰撞與接觸的特性，競賽規則規定跆拳道運動員應穿戴合格護具。護具是運動員用於預防撞擊傷害的重要個人防護用具。運動過程中的汗水、防禦動作、手或腳的移動或攻擊動作皆可能造成護具偏離原位，進而增加運動員受傷的風險，甚至影響運動員的專注力與攻擊節奏，使運動員無法正常展現應有的實力。此外，運動過程會產生大量體熱跟汗水，護具包覆下的皮膚因汗水蒸散不易使散熱更為困難。而當排汗與散熱的機轉受限，便可能引起熱傷害。
本研究針對跆拳道運動個人防護用具之摩擦及抗撞擊特性進行研究，並藉由實驗量測運動員於運動過程中的皮膚表面溫度變化。經實驗得知，護具的包覆會對皮膚產生約1.42 (0.11) kPa的平均接觸壓力。護具內的EVA發泡體進行適當的鑽孔加工後，能減少17.12 % 的皮膚表面溫度提升量，並提升9.19 % 的抗撞擊能力，且較厚的護具面料有助於抗撞擊能力的提升。與皮膚接觸的面料部分，人造皮革在潮濕的情況下容易因潤滑作用而導致摩擦係數快速下降；具吸水或排水能力的面料摩擦係數隨表面水分含量上升而下降的幅度較小。
結合實驗數據與摩擦理論，本研究探討黏附摩擦及變形摩擦對摩擦係數的貢獻。對鋼球與面料的摩擦系統，變形摩擦的貢獻較多，黏附摩擦僅在低負載的情況下較為明顯。對面料與皮膚的摩擦系統，黏附摩擦的貢獻較多，變形摩擦則較不顯著。動摩擦係數相對於靜摩擦係數所減少的量主要是黏附摩擦之損失所致。透過本研究，期望能作為跆拳道護具及相關防護用品在設計製造上的參考，並提供一種分析比較黏附摩擦及變形摩擦的方法。

This study evaluated the effectiveness of forearm guards and shin guards in Taekwondo. By frictional test of six kinds of fabric, fabric with the ability of moisture absorption or releasing showed better performance in slip resistance. Both static and dynamic coefficient of friction are composed of adhesion and deformation component. We separate out each component by combining two-term model of friction and curve fitting of experimental data. To evaluate cushioning property of the Personal protective equipment (PPE), EVA foam was tested by drop-weight impact tester. A hole-drilled EVA foam showed better cushioning property by decreasing 9.19% impact force. Hole-drilled EVA foam has lower stiffness, hence it can absorb impact energy by greater deformation.

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