J231024 新・テニスの物理学 : ストリングとスピン打法によるパフォーマンス向上と障害低減([J23102]スポーツ・アンド・ヒューマン・ダイナミクス(2))

元データ 2011-09-11


There has been no question that some strings do provide a better grip than others, but that did not guarantee that the ball will produce more spin. Furthermore, experiments with hand-held rackets has been needed to solve the difficult question of how players can tell the difference between different strings when laboratory tests indicate that they should play the same. The previous paper performed an experiment measuring the spin rates of used, notched strings in both their natural condition an.d after applying a lubricant to the string intersections to facilitate tangential string movement. It found that the lubricated notched strings produced 30% more spin than the unlubricated notched strings. The lubricant materials are effective to the notched strings, because the lateral movement and snap-back of the main strings increase spin. It also showed that the more spin results in the reduction of shock vibrations of the wrist joint during impact. Furthermore, it was shown that the used natural gut with notches decrease 70 % of spin rate compared to the new natural gut without notches in the another experiment, which has remained to be seen whether the same results will be obtained. Recently, International Tennis Federation researchers reported that the same movement that was observed with lubricated strings occurs with copoly as well. Copoly strings slippery and stiff generate more spin not because of more friction, but because of less. The old argument was that the better the grip between the strings and the ball, the more spin we would get, but that was not true. Many experiments has started to investigate whether the lateral movement and snap-back of the main strings increase spin, which strings generate the most spin, and so on. This paper discussed the improvement of performance and injury prevention with proper string and proper body movement of a player.


中川 慎理 埼玉工業大学
川副 嘉彦 埼玉工業大学
上杉 昭二 (株)ゴーセン研究開発センター