a****n
发帖数: 4734 | 1 看费德勒打球这么多年，总觉得他握拍比较特别，手腕用的比较多，但又一直不得要领。
这个夏天刚琢磨一点体会，关键词1：直角；关键词2：弹簧（扭力弹簧）。
我以前一直认为手腕是力传导的一个环节，手腕就像铰链一样并不参与发力或增加力量
，但是灵活随动的手腕是流畅发力必不可少的一环。所以现代网球正手基本都是雨刷式
随挥，nadal就是典型。
可是federer的手腕好像更多的参与了发力，以常识来看，手腕发力来扭转极高的动量
和动能的球拍，就像用一根火柴来撬动一个哑铃一样是不符合力学常识的。其实
federer的手腕就像一个扳开的弹簧一样，只在恰当的时机利用自身弹性回复的力量顺
势增加那一点点速度。
federer在准备击球前，握拍时候，拍子和前臂大致保持90度直角（就像弹簧在自然状
态），保持到大部分的引拍， 一直到击球前最后一刻才打开手碗使拍柄的尾部对准来
球（就像弹簧张开），并且马上随着手臂的挥动，在击球那一刹那，手腕靠着自然的弹
性回复到放松状态。用不太准确的话来描述这个过程就是：90度-〉180度-〉-击球-〉
90度。 数字肯定是不准确的了。
这种手腕的用法对于击球大概能提高10%的速度，但确实可以明确感知的提高。还有，
好像只用东方式握拍可以把牌子握到90度，也就是说只用东方式握拍可以用这个方法。
以上言论谨代表个人摸索过程中的一管之见，仅供参考，欢迎探讨。 | Q*****i
发帖数: 1126 | | a****n
发帖数: 4734 | | a****n
发帖数: 4734 | 4 准备动作：90度
引拍：90度
拍头向前（如果不是90度，拍头是指向侧面）
http://tennisnow.com/getmedia/6a32e0c3-5de5-4344-816a-8c2d4f771
击球前，手腕打开，弹簧处于负载状态(之前说180度不准确，实际上远大于180)
击球瞬间，弹簧能量释放，速度达到最大
随挥，手腕放松，慢慢回到90度 | x*d
发帖数: 1696 | 5 double ~90-degree (one for elbow, one for wrist) has long been discussed, at
least in a book written 15 years ago, though usually for western and semi-
western grip (BTW, Federer is usually near semi-western).
Federer's biggest power generator is his full-body-turn-before-contact. In
many pictures, he turns his head more than almost all other players, in
looking at the contact. Sometimes his shoulder turns so much (before hitting
the ball) that it looks nearly being in front of the contact, almost
against the common sense of making contact in front of body.
Rarely players including pro can do this.It's very difficult to focus and
highly error-prone.
领。
【在 a****n 的大作中提到】
: 看费德勒打球这么多年，总觉得他握拍比较特别，手腕用的比较多，但又一直不得要领。
: 这个夏天刚琢磨一点体会，关键词1：直角；关键词2：弹簧（扭力弹簧）。
: 我以前一直认为手腕是力传导的一个环节，手腕就像铰链一样并不参与发力或增加力量
: ，但是灵活随动的手腕是流畅发力必不可少的一环。所以现代网球正手基本都是雨刷式
: 随挥，nadal就是典型。
: 可是federer的手腕好像更多的参与了发力，以常识来看，手腕发力来扭转极高的动量
: 和动能的球拍，就像用一根火柴来撬动一个哑铃一样是不符合力学常识的。其实
: federer的手腕就像一个扳开的弹簧一样，只在恰当的时机利用自身弹性回复的力量顺
: 势增加那一点点速度。
: federer在准备击球前，握拍时候，拍子和前臂大致保持90度直角（就像弹簧在自然状
| g*****y
发帖数: 7271 | 6 不觉得这是为了什么弹性，我觉得是减少转动惯量而已。
而且也不是非东方握拍不可的，你仔细看看nadal的正手，
也是有很明显的这个动作的。
【在 a****n 的大作中提到】
: 示意图来了
| a****n
发帖数: 4734 | 7 的确，你说的那个是早就被说过无数次的。但是我说的不是这个双弯曲。btw, federer
是直臂击球。
at
hitting
【在 x*d 的大作中提到】
: double ~90-degree (one for elbow, one for wrist) has long been discussed, at
: least in a book written 15 years ago, though usually for western and semi-
: western grip (BTW, Federer is usually near semi-western).
: Federer's biggest power generator is his full-body-turn-before-contact. In
: many pictures, he turns his head more than almost all other players, in
: looking at the contact. Sometimes his shoulder turns so much (before hitting
: the ball) that it looks nearly being in front of the contact, almost
: against the common sense of making contact in front of body.
: Rarely players including pro can do this.It's very difficult to focus and
: highly error-prone.
| a****n
发帖数: 4734 | 8 嗯，你说得那个90度是手背弯曲与手臂成90度。
我说的东方握拍90度，手背是基本不弯取的。就像握着菜刀和锤子的感觉。
【在 g*****y 的大作中提到】
: 不觉得这是为了什么弹性，我觉得是减少转动惯量而已。
: 而且也不是非东方握拍不可的，你仔细看看nadal的正手，
: 也是有很明显的这个动作的。
| a****n
发帖数: 4734 | 9 确实，这个发力的机制几乎每个选手都会多多少少. 只是federer的手腕角度变化更大
。相对来说，半西或者西方握拍，手腕是转动的角度比较大，比如德约。而federer是
平面的开合角度比较大，转动当然也有。 | x*d
发帖数: 1696 | 10 you are right, his way is like extreme whippin. While the power comes from
the the highly flexible body turn, the wrist provides the last piece, the
top spin. If you try his grip (between eastern and semi-western), you can
feel it. Sometime Sampras (eastern grip) uses similar trick in running
forehand passing.
federer
【在 a****n 的大作中提到】
: 的确，你说的那个是早就被说过无数次的。但是我说的不是这个双弯曲。btw, federer
: 是直臂击球。
:
: at
: hitting
| | | a****n
发帖数: 4734 | 11 发力有很多环节，几个主要的环节已经教科书一样的清楚了，比如你说得body turn.
你说的都对，而且跟这个帖子的观点不矛盾。
【在 x*d 的大作中提到】
: you are right, his way is like extreme whippin. While the power comes from
: the the highly flexible body turn, the wrist provides the last piece, the
: top spin. If you try his grip (between eastern and semi-western), you can
: feel it. Sometime Sampras (eastern grip) uses similar trick in running
: forehand passing.
:
: federer
| x*d
发帖数: 1696 | 12 look at Kuerten's forehand.
【在 a****n 的大作中提到】
: 发力有很多环节，几个主要的环节已经教科书一样的清楚了，比如你说得body turn.
: 你说的都对，而且跟这个帖子的观点不矛盾。
| a****n
发帖数: 4734 | 13 很多顶尖选手，比如德约 。。。也没有这点关键的小动作，但是正手依然强大。只是
老费多了这一点，好像可以看起来更轻松的动作就可以打出犀利强劲的正手。
感觉老费的正手很省力，效果很强大。我想大概这10%的作用是原因之一。 | a****n
发帖数: 4734 | 14 有点像孟菲斯
【在 x*d 的大作中提到】
: look at Kuerten's forehand.
| x*d
发帖数: 1696 | 15 Sorry to say but I feel what you said is misleading.
For anything there is cause and there is consequence. Federer's apparent
more extended wrist, i.e. "这点关键的小动作", is not the cause but is the
consequence of his extreme body turn. Try turn your body very first and fast
, and keep the wrist relax, you can feel that your racket will naturally lag
behind more, which makes it look like your wrist is more extended.
In another word, Federer did not "use" his wrist, "这点关键的小动作" is a
natural response of his prior body action, as long as it's relax.
On the other hand, there is someone else you can perhaps apply your "use
wrist" theory, like Kuerten, although using a western grip. His wrist
movement is more extreme than most players (including Federer) before,
during and after a contact, with an apparent unnatural finishing.
【在 a****n 的大作中提到】
: 有点像孟菲斯
| g*****y
发帖数: 7271 | 16 I second this.
fast
lag
【在 x*d 的大作中提到】
: Sorry to say but I feel what you said is misleading.
: For anything there is cause and there is consequence. Federer's apparent
: more extended wrist, i.e. "这点关键的小动作", is not the cause but is the
: consequence of his extreme body turn. Try turn your body very first and fast
: , and keep the wrist relax, you can feel that your racket will naturally lag
: behind more, which makes it look like your wrist is more extended.
: In another word, Federer did not "use" his wrist, "这点关键的小动作" is a
: natural response of his prior body action, as long as it's relax.
: On the other hand, there is someone else you can perhaps apply your "use
: wrist" theory, like Kuerten, although using a western grip. His wrist
| a****n
发帖数: 4734 | 17 >Sorry to say but I feel what you said is misleading.
No problem. Happy to discuss it.
>For anything there is cause and there is consequence. Federer's apparent
>more extended wrist, i.e. "这点关键的小动作", is not the cause but is the
>consequence of his extreme body turn. Try turn your body very first and
fast
>, and keep the wrist relax, you can feel that your racket will naturally
lag
>behind more, which makes it look like your wrist is more extended.
Agree. Most of modern players do the same thing at their forehand.
>In another word, Federer did not "use" his wrist, "这点关键的小动作" is a
>natural response of his prior body action, as long as it's relax.
Depends on how to define the word of "use".
Naturally use is also use. Relax is always right.
>On the other hand, there is someone else you can perhaps apply your "use
>wrist" theory, like Kuerten, although using a western grip. His wrist
>movement is more extreme than most players (including Federer) before,
>during and after a contact, with an apparent unnatural finishing.
OK, now the point.
This is not my "use wrist" theory.
It's a common, proven right "use wrist" theory which been used by all morden
players.
it's textbook theory.
Again, 你说的都对(it's like a text book which i have read many times for
years.)，而且跟这个帖子的观点不矛盾。
Just it is not what i am talking about.
textbook rules are right and have been proven again and again.
And, u r right, textbook rules did 100% work for most of players.
What i wanna say is that , for some eastern grip players like federer,
another 5% or 10% 关键的小动作 is working except 90% of textbook rules.
That's why Federer hit forhand more efficientlly, less effort more power and
speed (that's my poit of view and the motivation of "use wrist" theory) .
It is hard to explain such a 关键的小动作 by writing. | x*d
发帖数: 1696 | 18 Yes, good discussion with you, and it's nice you raised the point.
My point is that what makes Federer not anybody else, e.g. that 5%-10%
excellency in his forehand comparing to others, is his extreme pre-turn of
body, which is his signature. Wrist is part of it, but not the responsible
part for that 5-10%.
You're right at the 弹簧, but I don't believe he means to keep any angle in
a shot.
It's actually fun for us to try his shot, you will find many mishits, and
hit on the rise is almost impossible, that says why he can catch a thrown
tennis ball at 2-year old :)
【在 a****n 的大作中提到】
: >Sorry to say but I feel what you said is misleading.
: No problem. Happy to discuss it.
: >For anything there is cause and there is consequence. Federer's apparent
: >more extended wrist, i.e. "这点关键的小动作", is not the cause but is the
: >consequence of his extreme body turn. Try turn your body very first and
: fast
: >, and keep the wrist relax, you can feel that your racket will naturally
: lag
: >behind more, which makes it look like your wrist is more extended.
: Agree. Most of modern players do the same thing at their forehand.
| B********d
发帖数: 1776 | 19 怒赞楼主和几位楼上的钻研精神
网球版很久没有这么有营养的帖子了!!!!!! | a****n
发帖数: 4734 | 20 Body turn generates most of the speed. No doubt.
Actually following pic can explain something about my point
we can see the wrist angle changed.
with/without 弹簧 trick, the wrist angle is gonna change anyway, like a
joint.
But if imagine there is a loading wrist弹簧 at first pic, then at 2nd pic,
the the acceleration will be noticeable higher than w/o wrist弹簧.
I don't know if player really know or care all mechanics of their hitting.
Some kids hit balls like textbook but I am sure that they don't know the
theories/textbooks. They did just like they did, part of natural part of
correct training. But mechanics is always there no matter player realized or
not.
in
【在 x*d 的大作中提到】
: Yes, good discussion with you, and it's nice you raised the point.
: My point is that what makes Federer not anybody else, e.g. that 5%-10%
: excellency in his forehand comparing to others, is his extreme pre-turn of
: body, which is his signature. Wrist is part of it, but not the responsible
: part for that 5-10%.
: You're right at the 弹簧, but I don't believe he means to keep any angle in
: a shot.
: It's actually fun for us to try his shot, you will find many mishits, and
: hit on the rise is almost impossible, that says why he can catch a thrown
: tennis ball at 2-year old :)
| | | z*****k
发帖数: 600 | 21 Nice analysis. We knew the spring mechanism as a power generator. I'd be
more curious about anything from his visible motion that makes his shot so
accurate. What tool did you use to create the skeletal graphics ? It's nice.
【在 a****n 的大作中提到】
: Body turn generates most of the speed. No doubt.
: Actually following pic can explain something about my point
: we can see the wrist angle changed.
: with/without 弹簧 trick, the wrist angle is gonna change anyway, like a
: joint.
: But if imagine there is a loading wrist弹簧 at first pic, then at 2nd pic,
: the the acceleration will be noticeable higher than w/o wrist弹簧.
: I don't know if player really know or care all mechanics of their hitting.
: Some kids hit balls like textbook but I am sure that they don't know the
: theories/textbooks. They did just like they did, part of natural part of
| a****n
发帖数: 4734 | 22 Thanks.
I googled all pictures.
I believe that skeletal graphics is coming from following video:
http://www.youtube.com/watch?v=pPLmCqGIotM&feature=related | z*****k
发帖数: 600 | 23 Thanks for the video link. Thought you might have access to the data set.
【在 a****n 的大作中提到】
: Thanks.
: I googled all pictures.
: I believe that skeletal graphics is coming from following video:
: http://www.youtube.com/watch?v=pPLmCqGIotM&feature=related
| R*****n
发帖数: 610 | 24 嗯。终于搞清楚你想说的话题。。
Federer的正手是东方式握拍。挥拍的线路也很平。整个动作平击得成分很多。你说的
直角。我觉得是“扇耳光”式的手腕加力。 其实跟高尔夫球的手腕延迟加速一个道理
。 在加上上身躯干的转动。难怪他的正手如KEN123所说，爆炸式的突然加速。
但是我觉得他手腕最大的优势还在于击球时候扭动。给球刷出极大的上旋。落地后前冲
的很厉害。堪称钢腕！
但是我现在觉得PRO能用这么大力量和平及。在与每天的艰苦训练。看和移动得准，我
们还是先拉好上旋。打出稳定性，再加力吧。 | a****n
发帖数: 4734 | 25 的确很难用文字解释。“扇耳光”很形象。我跟另一位网友解释：手腕角度的变化有点
像DJ在台上搓唱片时候手腕运动的方向。就像以手表的中心为轴而转动手腕。当然同时
也有雨刷正手的转动。 | L****n
发帖数: 12932 | 26 小心你的手腕。 没有金刚钻别揽瓷器活。 在全力击球的时候flip手腕， 没有那种力
量， 柔韧和精准 - you are asking for trouble. | a****n
发帖数: 4734 | |
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