TENNIS

　　6月19-22日我又去北京參加中國網球協會體能教練員培訓。

（仍然待續，照片無數，實在太忙）

　　今年5月21-24日我去北京參加了首輪快易網球教練員培訓。

　　每一次的培訓都能讓我的眼睛更亮一些再亮一些直到變成烈烈熊日……

（待續）

（此處該貼圖）

我自幼开始和网球亲密接触，然后和它一起连滚带爬直到现在，那么些年来，虽说表面上看有些单一，但实际上网球真的是一项底蕴极为丰富的有无穷魅力的运动。真正要打好网球并非是我们直观上所理解的——“只要多多击打那个长着绿毛的球就能把球打好了”的。

我把它假设成一个立体的多面体，有些面是我们原地不动站在这里用直观的视角所看不见的盲区。但是，我们必须知道，它们的确在那里，它们是存在的，只是我们现在没有看见。所以，不如让我们一起开始慢慢地挪动脚步，那将展现在你面前的，是无限的收获与乐趣。

网球爱好者一定很清楚，如果真的把网球打出回合的话，对球的控制，只是其中一部分。我们的大多数注意力也集中在此。但如果说，我们根本没有触碰到球，那哪来的控球可言？那么在去争取触碰到那个球之前，我们又需要做好怎样的一个准备呢？即使触碰到了球，我们则没有事先作出敏捷的反应，不能灵巧又协调地调节整个躯干，不能保持平衡，又没有基础力量，那么我们就还是不能够有效地控制住它。所以在网球运动中不可或缺的，就是身体素质的训练，这部分也是最容易被忽视的关键环节。因为很多业余学习网球的爱好者们只是为了打球而纯粹地练习“打很多的球”，这样的训练是会失衡的，在原有的基础上也无法再得到更多的提高。很多时候，我们说“打不动了”，笼统简单的说就是两方面原因，不是体力不够了，就是没有再多的力气了。这样的现象相当普遍，那么我们所要寻找的突破口，就是身体素质训练了。

身体素质的训练会锻炼到肌肉和四肢，它们会让我们在网球场上充分发挥出力量、爆发力、耐力、速度以及柔韧性的优势。从而能在网球运动中体会并享受到真正的乐趣。

对于身体素质训练，并不是只针对于专业网球运动员的。作为业余网球爱好者，是可以从中获取更多的能量的，那样才能适当保证我们能够做出更正确、更安全的动作。真正能够迅速直接影响到打球质量的，多数是与体力有关。我们可以试着从一些其他的简单又熟悉的运动中旁敲侧击地对自己进行锻炼，从而循序渐进。比如：我们能从做仰卧起坐、高抬腿、平躺抬腿、俯卧撑、引体向上、原地深蹲跳、蛙跳这些运动中受到力量和爆发力的训练；可以从跳绳、竞走、长跑、短跑、爬坡跑、跑楼梯、折返跑、骑单车、游泳、滑冰、拳击、有氧舞蹈、篮球、足球等这些运动中受到有氧耐力、无氧耐力和速度的训练；另外，柔韧性的练习则是一些身体的伸展运动。

以上这些运动项目足以使我们的握力、腕力、臂力、肩部、腹部、背部、臀部、腿部以及脚踝能得到全方面综合性的提高。如果你拥有一个这样全面性的健康的身体素质后，再去打网球，就会感觉到在原本单单只是打网球的基础上要轻松得多得多了。对于初级阶段的网球爱好者来说，效果应该是犹为显著的——当有了充沛的体力与力气后，在进行增强正手、反手的控球技术充分练习的基础上，我们就可以进一步尝试学习一些比如发球、高压球的高难度网球技术了。对于喜欢打比赛的中级或以上级别的网球爱好者们来说，那么就更能在那一场场不可预知赛时的杀戮中尽显优良身体素质的优势了。

　　在網球運動中，專業運動員的身體素質必須進行以下幾點基本訓練。

　　1、速度：短跑

　　2、靈活性、動態平衡和反應：折返跑；蜘蛛式折返跑

　　3、上肢和腹肌力量以及耐力：俯臥撐，比如一分鐘能做多少個；仰臥起坐，也是以一分鐘為准計算個數；高擡腿等

　　4、有氧耐力：長跑

　　5、柔軟性：坐姿雙腿伸直摸腳尖

　　6、下肢爆發力：垂直跳高

　　打網球不僅僅是打，如果你想更強大，必須結合以上一些身體素質訓練。

　　目前在我的學員中，我沒有實施過如此高標準的要求。但是大家要了解，如果你想把網球運動發揮得更完善，那麽就跟我一起這樣練起來。

　　今天要簡單分析下網球運動的生物力學，我也趁着運動后還尚未消退下去的激情順便復習一下。

　　了解生物力學，就能幫助一名球員的動作的發揮更具有效性。

　　“什麽是最完美的技術？”

　　我們要用“生物力學”來幫助你回答這個關鍵的問題：

　　最完美的技術可以界定在擊球和動作技巧中既能使力量和控制最有效地結合，有能將受傷的危險減少至最低程度的那種技術。

　　根據生物力學的首字母縮寫詞"BIOMEC"，容易記住用於網球的主要的生物力學原理。這個縮寫詞的含意是：

　　1、平衡（Balance）

　　2、慣性（Inertia）

　　3、反作用力（Opposite force）

　　4、動量（Momentum）

　　5、彈性能（Elastic energy）

　　6、協調鏈（Coordination chain）

一、平衡

　　平衡就是“保持動態或靜態均衡（一種穩定狀態）的能力”。鑒于網球是一種連續運動的體育項目，它要求動態平衡。例如，黨一名高水平選手處於最困難的情況下，他依然昂起頭，挺起胸，以便打出一個好球。

二、慣性

　　慣性定律指出：在受到某种外力作用前，人體將一直處於靜止或運動狀態。換言之，慣性就是人體對運動或停止運動的反抗。網球運動員怎樣才能，譬如說，從靜止狀態轉入快速移動、減速，然後快速改變方向。例如，黨你處在準備姿勢時，你的身體和球拍不在運動中，從而，具有一定量的靜止慣性。黨你對你的對手擊球作出反應時，你必須利用重心和足夠的地面反作用力，通過腿部肌肉收縮的運動來克服你的靜止慣性。我們用輕微屈臂擊球的慣性矩比用直臂擊球的慣性矩要小。從而，對轉體的防抗力減小，拍頭的速度加快。

三、反作用力

　　“對於每一個動作都有一種同樣的反作用”。我們通過腿部蹬地開始移動和運用擊球技術。地面給予等量的反作用力。這種地面反作用力提供了爆發性的第一動作的動力。例如，運動員開始他的發球動作時，他首先屈膝蹬地，而這一動作為他的大力發球提供了力量。

四、動量

　　“動量就是人體產生的力量，或更確切得說，就是質量乘速度。”

動量有兩种類型：1、綫動量，即直綫形動量。

　　　　　　　　2、角動量，即在一圓周運動中的動量。

　　綫動量是簡單地將身體重心移向你正在擊球的方向（如格拉芙反手削球），而角動量則產生于髖部和上體的轉動（如阿加西的反手擊球）。

五、彈性能

　　彈性能是“儲存在肌肉和肌腱中的因肌肉牽張而產生的能量”。黨肌肉牽張時，肌腱儲存能量的方式與彈性橫紋牽張時儲存能量的方式相同。例如，埃德博格發球上網后跨步時，他將能量儲存在腿部，從而黨他落地時，就可利用一種具有爆發力的啓動步去擊球。現代的球員在罰球和擊落地球的準備階段也運用這一原理“充電”（預牽張），它能產生更大的爆發力。

六、協調鏈

　　人體協調鏈涉及的是“体節的作用就像由一個環或身體的一部分產生的力量轉換成一環套一環的鏈條系統”（格儸佩爾，1984）

　　這些体節的最佳協調（時機）將允許從一個体節移至另一體節，有效地轉換為全身的加速。

　　通常理解為連結系統的協調鏈是最佳技巧得以有效發揮的基礎：

　　★產生最大的爆發力

　　★增強控毬能力

　　★延緩疲勞

　　★防止受傷

（以上内容摘自我的一些網球資料，發上來分享參考學習網球的樂趣）

T - The T is the location on a tennis court where the center service line intersects the service line to form the letter T.

take two - An expression meaning that the server should repeat both service attempts.

tank - To tank a match or point is to deliberately try to lose it.

teaching pro - A person who teaches people to play tennis and is paid for the service.

throat - Part of the racket just below the head.

tiebreaker - A method of completing a set when both players or teams have won six games.

titanium - A strong, lustrous, white metal element used in small amounts in the construction of some rackets.

topspin - Bottom-to-top rotation on a ball, like a car wheel going forward.

touch - The ability to hit a variety of precision shots.

twist - A serve in which the ball's spin, imparted by the racket, is the opposite of what it would normally be. A right-hander's twist serve produces left-to-right spin on the ball.

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umpire - A person responsible for officiating a match between two players or teams.

unforced error - A point lost with no pressure having been exerted by the opponent.

United States Tennis Association (USTA) - A national, noncommercial membership organization whose mission is to promote and to develop the game of tennis.

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vibration dampener - A rubber or plastic device inserted at the base of the racket strings (near the throat) to reduce the vibration on impact with the ball.

volley - A shot hit before the ball bounces on the court.

western grip - A way of holding the racket in which the wrist is positioned directly behind the handle.

wide - An expression used by some players to indicate a shot went out beyond the baseline.

wide-body - A description of a racket frame with a very wide head.

Wimbledon - A tournament in England, generally considered to be the most prestigious in the world.

World Tennis Association (WTA) - An organization consisting of the world's leading female professional players.

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yoke - The part of the racket immediately below the head; the upper part of the shaft; the throat.

(THE END)

second - An informal expression used by some players to indicate that the first serve is out.

semiopen stance - A hitting position between an open and square stance in which the feet are aligned so that the body is partially open to the net.

semiwestern forehand grip - A way of holding a racket that is approximately halfway between an eastern and western forehand grip.

serve - The shot used to put the ball into play at the beginning of a point.

service break - The loss of a game by the player serving.

service court - Either of two alternating areas into which the ball must be served. Its boundaries are the net, the center line, the service line, and the singles sidelines.

service line - The line that is parallel to, and 21 feet from, the net.

set - The part of the match that is completed when a player or team has won at least six games and is ahead by at least two games.

set point - The stage of a set when a player or team can win the set by winning the next point.

shadow swing - Like shadow boxing, a practice method in which a player goes through the motions of a swing without hitting a ball.

shaft - Part of the racket between the head and the grip.

sideline - The boundary line that runs from the net to the baseline. The singles sidelines are closer to the center of the court than the doubles sidelines.

single-elimination tournament - A type of competition in which players' mames are drawn and placed on lines in a tournament bracket roster. Matches are played between players whose names appear on connected bracket lines. Plays who win advance to the next round of competition; those who lose a match are eliminated from competition.

slice - To hit the ball with sidespin, like the spin of a top.

slow court - A court with a surface on which the ball bounces and slows down after the bounce.

split set - An expression used to indicate that two players or teams have each won a set.

square stance - A position in which the toes of both feet form a line parallel to either sideline.

straight sets - A reference to winning a match without losing a set.

string savers - Small pieces of material that attach to racket strings to make them last longer.

stroke - The manner in which a ball is hit (forehand, backhand, volley, and so on).

sweet spot - The exact place on the racket face that produces controlled power with no vibration (see also power zone).

synthetic - A type of racket string made from specially designed nylon.

net game - Shots hit while playing near the net, such as volleys and smashes.

net umpire - An official responsible for calling let serves.

no - An informal expression used by some players to call shots out.

no-ad - A scoring system in which a maximum of  7 points constitutes a game. For example, if the score is tied at 3 points for each player, the next player to win a point wins the game.

no-man's-land - The area of the court between the service line and the baseline. This area is usually considered a weak area from which to return shots during a rally.

not up - An expression used to indicate that a ball has bounced twice on the same side of the court before being hit.

nylon - A strong synthetic material commonly used for racket strings.

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off hand - The hand that does not hold the racket.

open stance - A hitting position in whcih the feet are parallel to the net.

out - A call indicating that a shot has bounced outside a boundary line.

overgrip - A one-piece grip that slides over the original racket grip.

overhead smash - A hard, powerful stode hit from an over-the-head racket position.

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pace - The velocity with which a ball is hit, or the velocity of the ball.

passing shot - A groundstroke hit out of reach of an opponent at the net.

percentage shot - The safest, most effective shot hit in a particular situation.

placement - A winning shot hit to an open area of the court.

playing pro - A person who makes a living playing tennis.

poaching - When a doubles player at the net cuts in front of his or her partner to hit a volley.

point penalth - A system in which a player must be penalized points, games, or even matches for improper conduct.

power zone - The area of the racket's hitting surface that produces controlled power with no vibration (see also sweet spot).

professional (pro) - A person who plays or teaches tennis for money.

pro set - A match that is completed when one player or team has won at least eight games and is ahead by at least two games.

pusher - A type of player who is consistent but who hits with very little pace.

put-away - A shot taht is literally put away (out of reach) from an opponent.

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qualifying round - A series of matches played to determine which players will be added to a tournament field.

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rally - An exchange of shots.

ready position - The position in which a player stands while waiting for a shot.

receiver - The player to whom a serve is hit.

referee - An official responsible for supervising all competition during a tournament.

returner - A player who gets everything back but does not play aggressively.

round-robin - Competition in which all participants compete against each other in a series of matches. The player or team finishing the competition with the best win-loss percentage is the winner.

rush - To move toward the net following a forcing shot.

International Tennis Federation(ITF) - The international governing body of tennis.

invitational tournament - A tournament open only to players who have been invited to participate.

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junior racket - A racket less than 27 inches long that is usually lighter than standard rackets and has a smaller grip.

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Kevlar - A synthetic fiber used to strengthen tennis racket frames.

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ladder tournament - Competition in which the names of participants are placed in a column. Players can advance up the column (ladder) by challenging and defeating players whose names appear above their own.

let - A serve that hits the top of the net and lands in the proper service court. Also, an expression used to indicate that a point should be replayed for any of a number of other reasons.

linesperson - An official who is responsible for calling shots either in or out at the baseline, service line, or center service line.

lob - A high, arching shot.

lob volley - A lob hit with a volley.

long - An informal expression used to indicate that a shot went out past the baseline.

love - An archaic but commonly used way to say zero in the tennis scoring system.

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main strings - The vertical strings running from the top to the bottom of the racket head.

match point - The stage of a match when a player can win the match by winning the next point. The term is used by spectators and television announcers during a match and by players after a match. It is not, or should not be, used by the umpire or players in calling out the score.

mixed doubles - Competition pairing a man and woman on one team against a man and woman on the other team.

hacker - A person who does not play tennis well.

half volley - A shot hit just after the ball has bounced on the court. Contact is made below knee level.

head - The upper part of the racket where the strings are attached.

head heavy - A racket that has a balance point more than 1/4 inch from the center (midpoint of the racket's length) toward the head.

head light - A racket that has a balance point more than 1/4 inch from the center (midpoint of the racket's length) toward the handle.

hindrance - Called when a player is hindered by either an opponent or a spectator. It results in a let or a point awarded to the player hindered.

hitting surface - The flat surface formed by the strings.

holding serve - The server has won the game that he or she just served.

hook - A slang term meaning to cheat.