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标题: 意淫TFR ( Two-Footed Release ) [打印本页]

作者: IntoTheWind 时间: 2013-3-19 08:48
标题: 意淫TFR ( Two-Footed Release )
本帖最后由 IntoTheWind 于 2016-4-2 20:48 编辑

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2016-04-02

经过一些实践操作, 现在我认为, TFR就是巧妙一点的Steering.
这篇文章完全没有实际意义, 请大家不要被误导了.

暂时不删除, 因为:
1. 还在继续思考这个命题, 也许未来有东西补充.
2. 留在这里给后来人做个警示
3. 这篇文章的理论和写作, 让我很不舍得删.

未来大约会删掉的, 再漂亮的理论和写作, 如果立论是错的, 就没有价值了.

否定这篇理论, 不等于否定PMTS. 不影响PMTS的Carving, TFR的价值和意义.
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2015-12-18
在我的这个时刻的认知里, TFR不是内脚引导. 内脚引导就是个乌托邦, 理论很诱人, 然并卵.

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警告：一定要先炼成了OSD和CB&CA，再考虑练习TFR。功力不到，会练岔气

TFR是PMTS的看家本领. 每每涉及TFR的物理机制时, 老怪总是语焉不详. 神秘面纱之下, TFR已成为信徒的信仰，非信徒的挑战武器。

TFR定义

TFR，是相对乾坤大挪移 ( Phantom Move) 的OFR ( One-Footed Release )而言. 本意是说在换刃过程中，两脚同时承重。但是老怪把它的定义引申了，TFR包括了后续的整个转弯过程。这个引申造成了很多的困扰。但是PMTS是老怪定义的，啥也不说了。其实老怪还有一个名词, Brushed Carve, 更适合描述这种转弯方式.

TFR物理机制

TFR的物理原理是漂移 ( Drifting ). 当你往前滑的很爽的时候, 突然右侧衣服挂在了树上, 那么你就会绕着树急速右转弯, 这就是漂移. TFR的内脚作用就相当于那棵树. 内脚的Tipping动作, 以及重心的前压, 客观上造成了内脚外刃的前端切雪较多, 形成了一个阻力点, 从而拉动全身绕这个点旋转. 这就是TFR转弯的源动力, 也可以称为内脚引导. 这个转弯结果跟Steering一样, 都是雪板的pivoting, 但是发力机制不同. TFR不需要身体的Twisting / Pushing, 一切自然而然的发生.

换刃用双脚承重, 推迟外脚切刃, 是雪板漂移的前提条件.

TFR技术要点

修炼TFR技术的前提是已经掌握了OSD (Outside Ski Dominant) 和CB&CA ( Counter Balance & Counter Action). CB&CA相当于反弓 ( Angulation ).

TFR内脚要承重. 如果OSD不过关, 内脚承重份量就把握不好, 练TFR就成了双脚Pivoting.
反弓不够的时候练TFR, 两脚容易分开, 结果是外八字.

OSD和反弓都练到位之后, 以双脚同时释放开始, 加强加大内脚Tipping, TFR就水到渠成了. O型腿不时会出现, 是由于内脚比外脚立刃还高, 可以增强漂移的效果.

TFR的优势和缺点

首先, 漂移的本性, 使TFR的弯可以很急, 半径很小, 转弯过程很快.
其次, 不需要身体的Twisting / Pushing, 意味着更多的弹性和动态，另外对膝关节,髋关节有很好的保护作用.

缺点是启动慢, 需要先把反弓做出来，刃立起来，才能开始转弯. 所以用Pivoting来启动, 在Fall Line ( 2点 ) 再开始内脚引导, 是BPST ( Bullet Proof Short Turn ) 的关键. 这里注意, 老怪不认为自己用了Pivoting.

实践中纯粹的TFR相当少见，只有老怪在力推。这大概也反证了TFR可能并不如Steering实用。

TFR练习

警告：一定要先炼成了OSD和CB&CA，再考虑练习TFR。功力不到，会练岔气

决定练习之前请仔细阅读老怪的原话：

First, the "Two Footed Release" may be well beyond your capabilities. In fact, it may hurt your skiing, if you don't have a weight transfer, and balancing ability, book 1, or tipping ability, book 1 and 2. Many people think I just write these books to make money and that most of it is fluff, well I have news for you, every page in my books holds information you need to know, if you want to teach yourself to ski. I have never written a page to fill space.

You might think you have done a TFR, but it may well include an extension or a push to a-wedge and a full upper body rotation. You have to perfect the TFR, with PMTS movements not your old movements you learned from Trad. teaching, and don't just think you have already mastered a TFR. The TFR is a test of all the right PMTS Essentials, I'm amazed people think they have mastered it so easily and quickly, without even having a qualified professional PMTS instructor to validate this. Without a reasonably good TFR you will never progress to the BPST. We spend many hours in our camps teaching the elements of a good TFR and many don't get it the first camp they attend.

I'm sorry I make it look so easy in my videos, but I have skied for 61 years and trained for skiing my whole life, I already developed PMTS movements years ago, yet the TFR is still challenging, especially done slowly. The biggest difference between the TFR and a BPST, once you have the basics perfected, is more tipping and higher angled tipping earlier.

具体练习可以参考老怪的视频：
http://www.youtube.com/watch?v=GPM7gwZwVDU

注意Drill的前半个弯, 是为了让你习惯双脚释放, 不切刃就到Fall Line的感觉. 实战这部分是用Pivoting快进掉的, 不要误以为这就是TFR了.

参考文献:
http://skichinese.com/forum.php?mod=viewthread&tid=6664
http://www.pmts.org/pmtsforum/vi ... t=1891&start=30
http://www.pmts.org/pmtsforum/viewtopic.php?f=6&t=1624

Q&A

1. TFR跟Steering有区别么?
TFR跟Steering转弯的结果相同，都是雪板的pivoting，所以看起来有点像。但是发力方式，物理机制完全相反。
Steering是靠身体的Twisting / Pushing，来带动雪板转动，有很强的主动性。
TFR是靠内脚引导，雪板带着身体转，转弯基本是被动的。

2. TFR比Steering更高级么?
TFR的优点是转弯半径小, 过程短. 不需要身体的Twisting / Pushing, 关节损伤小.
但是Steering启动快, 应变更灵活. 从实战效果上看, 很难说哪个更高级. 把二者结合起来用，也许更好。
Steering更符合人类的本能, 上手容易，见效快. TFR要求有很好的技术基础, 才能开始修炼. 从这个意义上说, 也许TFR高级那么一点点.

3. TFR比Steering更适合Mogul么?
没有一手经验真不好说. 二者结合也许更好.

4. TFR和CSIA的中级弯有区别么?
TFR用的是内脚引导技术, 中级弯用的是Steering技术, 形似而神不同.
高手的中级弯, OSD和Angulation都足够了, 内脚跟外脚同步立刃, 类似于内脚Tipping的效果, 就会有一定的TFR成份在里面.

5. 刷刻是什么?
刷刻，Brushed Carve. 老怪说, 把TFR连起来就是刷刻了. 所以概念相当混淆. 前面所有的TFR, 用刷刻来代替, 其实更合适一些.

6. 老怪为什么不肯解释TFR的机制?
两种可能，一是老怪没搞明白TFR机制，二是老怪厌倦了解释。

作者: KuoiGuaBoarder 时间: 2013-3-19 08:55
膜拜大侠！

BTW: 不膜拜都不行

作者: bullpower 时间: 2013-3-19 09:17
本帖最后由 bullpower 于 2013-3-19 09:22 编辑

这。。。。咋CSIA考试时也做了啊（brady and bullpower)，
http://www.youtube.com/watch?v=GPM7gwZwVDU

作者: bullpower 时间: 2013-3-19 09:38
IntoTheWind 用内脚Tipping来带动就是TFR，外脚Steering带动就是Intermediate Turn 发表于 7 分钟前

两者都不是，关键是release, 两个板一起release（没刃）了，板自己就转。这个算什么？

作者: KuoiGuaBoarder 时间: 2013-3-19 10:34

bullpower 发表于 2013-3-19 09:38
IntoTheWind 用内脚Tipping来带动就是TFR，外脚Steering带动就是Intermediate Turn 发表于 7 分钟前

两 ...

这个区别呢, 要看人家屁股, 看出屁股的差别以后呢, 你再往下打量

原来是这样的啊

作者: jluo 时间: 2013-3-19 10:49
天下武学源于少林，天下滑雪又源于什么

相由心生，相随心灭，众施主切勿为外相所累

阿弥陀佛

作者: Bingster 时间: 2013-3-19 12:18
谢谢，学习了。

作者: b-p 时间: 2013-3-19 17:30
拜读！！！！

作者: skisnowboardca 时间: 2013-3-19 19:55
还没仔细看，光看题目和自创就无比膜拜，真是不膜拜都不行啊！！！！

作者: 雪在烧 时间: 2013-3-20 09:07
大侠厉害！！！这个必须置顶呀！

作者: 雪坷垃 时间: 2013-3-20 18:37

终于有点明白了，大侠讲解深入浅出，威武！~

作者: checkmoteur 时间: 2013-3-22 23:16
搜别的东西古怪地发现了关于harb的transition的一个评论，发出来参考一下：

The cons of the Cross Through (retraction) transition is that it leaves the legs flexed at edge angle neutral, and the hips therefore aft of the hips. It takes a quick/strong extension of the new outside leg post initiation if the skier is to get that leg long and strong, and him/herself fore balanced by the time the turn's apex is reached. It's very common for skiers trying to learn this deep retraction Cross Through transition (Harb vintage) to become stuck in the back seat, legs flexed and hips aft all the way through the turn as they anticipate the next deep retraction. This is why Harb has to stress so heavily the pullback of the feet, to try to overcome that problem, but even pulling the feet back will not solve the issue completely if the outside leg is not extended in unison.

Another problem with Cross Through is that you somewhat lose that solidly connected with the snow sensation through the transition. What you get is something called "float", in which the skis become very light as the body cross the skis. It happens because of the combined affect of down unweighting, rebound, and the virtual bump. The sensations of the connection that comes from Cross Over and Cross Through are very distinct and noticeable. Finally, that strong initiation that comes from the tall stance and center/fore balance of the Cross Over transition is lost in the hips aft Cross Through transition.

作者: IntoTheWind 时间: 2013-3-23 09:52

checkmoteur 发表于 2013-3-23 00:16
搜别的东西古怪地发现了关于harb的transition的一个评论，发出来参考一下：

The cons of the Cross Throug ...

呵呵，这个很有意思，不过是过去时了。

这篇文章说Cross Though会重心后座，这个是千真万确的。不过回避了Cross Through的好处。
现状就是，Cross Though已经成为主流，换刃Float俨然时尚，Cross Over即将入土。

这个作者是不是还在坚持Cross Over呢？

作者: checkmoteur 时间: 2013-3-23 10:05

IntoTheWind 发表于 2013-3-23 10:52
呵呵，这个很有意思，不过是过去时了。

这篇文章说Cross Though会重心后座，这个是千真万确的。不过回避 ...

从网站上的另外一篇文字看，此人平等对待cross over和cross through，认为这是工具箱里的两样工具，有不同作用，带来不同的乐趣。大侠有兴趣看的话俄再引一段好了：

When it comes to selecting a transition type, sometimes it's just a matter of personal preference, and sometimes not.  Most skiers use only one type of transition, simply because it's the only option they have with the tool box of skills they currently possess.  Skiers with more skills will have more transition options.  They may select a particular transition type because it's the best choice for the job at hand, or they may choose to use a certain transition simply for the fun of it.  Each transition type provides a unique experience, and sometimes we just have a craving for a particular sensation while we ski.

That said, crossover and cross through each have their individual attributes and compromises.  Let's take a look at them.

Cross though provides a faster transition from turn to turn, because the Center of Mass (CM) takes a more direct path of travel from one side of the skis to the other.  In crossover, the CM takes more of a pendulum shaped path of travel over the skis, rising, then falling.  When you need to end the old turn fast, and make the new turn happen NOW, cross through is a valuable transition.  Linking short radius arc to arc turns down a narrow trail would be a good example of a situation that could present such a need.  In longer radius arc to arc turns on a wide trail, more time is available for allowing the CM to take a longer trip across the skis, so crossover is a feasible option.

Crossover involves an extension of the old inside leg early in the transition, which brings you into a state of fore balance right at the start of the turn.  This is helpful for getting the shovels of the skis to strongly engage at the beginning of the turn, which produces an aggressive turn entry with full control of the front of the skis.  It results in a powerful sensation of control, with the body leading the skis into the turn.

Cross though is a little different.  With cross through your old inside leg goes through the transition still flexed, so the CM comes into the start of the turn aft.  Fore balance comes later in the turn, via an extension of the new outside leg, once the CM has begun to tip into the new turn.  That can certainly works fine too, but a potential problem can arise if the skier does not extend the outside leg, and goes through the whole turn aft, anticipating the flexion that will be needed in the next cross through transition.  It's a common happening for skiers new to carving, or just learning the cross though transition, and it leaves them in a weak and injury prone stance. This is why the cross over transition is generally the better vehicle for people learning how to do arc to arc carving.  Crossover promotes the quick adoption of a functional fore state of balance at the beginning of the turn that is confidence inspiring.

Cross through, in one respect is a bit more energy efficient. When you extend as your CM is crossing over your skis, you're extending vertically, and in the process working against gravity.  If you wait to begin extending your new outside leg until after your CM has crossed over your skis,  you'll be extending more horizontally.  Extending horizontally means not fighting gravity as much, so it requires a bit less work.

On the other hand, with cross through the legs never get to enjoy that moment of relaxation that comes from being extended between turns.  At that moment between turns, when the skis are flat on the snow, the forces are low, so the legs are granted a moment to rest. In cross through, the legs go through the transition deeply flexed, missing their rest opportunity, then are immediately fighting turning forces when they extend.  Many find the rest period provided by the the cross over transition, along with the early fore balance state it creates,  makes it overall a more relaxing way to ski.

So, as you can see, each transition has it's strong points, as well as it's compromises.  Choosing which to use is really a juggling act of which attribute we want to exploit, and which compromise we're willing to make, for any particular turn. Learn how to do both crossover and cross through, then experiment with each in various skiing situations, and experience for yourself how their unique characteristics shine or fade in each instance.  Not only will you be learning how best to apply your new transition skills, you'll be enhancing your ability to do so.

中间有几个地方跟楼主大侠所说好像是一个意思。

俄自己当然是不值一提的菜鸟了，如果也有资格谈一点感受的话，则好像转长弯倾向于cross over，短的类似cross through，所以觉得他那个工具箱的比喻也怪有意思的。

作者: IntoTheWind 时间: 2013-3-25 08:47
本帖最后由 IntoTheWind 于 2013-3-25 10:25 编辑

对不起，毒性太强，先锁起来。是毒药，又舍不得烧掉

都是YY出来的，俺完全不会TFR

作者: skisnowboardca 时间: 2013-3-25 16:20
一定不要烧掉，请教什么是cross through? 是cross under 吗？

作者: vicboy™ 时间: 2013-3-31 23:41
这艺术有点太高啊，大侠要亲临雪场指导。

作者: IntoTheWind 时间: 2015-12-18 09:33
翻出这篇来, 因为这篇是内脚引导的一个自洽的理论解释, 好过目前市面上的所有的那些自相矛盾的武侠理论解释. 然并卵.

比如说, 内脚引导就是内脚tipping,从而带动整个身体, 以致雪板转动. 我想起了左脚踩右脚, 右脚踩左脚的著名轻功, 于是不厚道的笑了笑.

喜欢玩概念的, 不如贩卖一下这篇.

作者: IntoTheWind 时间: 2015-12-18 09:36
再借机葱白一下瓜教授, 为啥葱白, 高山仰止啊, 不多说了, 都是泪

作者: cat 时间: 2015-12-18 10:19
同雪网的理论水平，早在上古时代就甩其他地方（比如那什么提啊，那什么野的）N条街了

楼上的终于能认识到教授的伟大，虽然比起我来晚了半个世纪，也还说明孺子可教了，我每天早上起床，都会把签名档里的教授语录大声念三遍，然后才去刷牙

作者: bullpower 时间: 2015-12-18 17:39

cat 发表于 2015-12-18 10:19
同雪网的理论水平，早在上古时代就甩其他地方（比如那什么提啊，那什么野的）N条街了

楼上的终于能认识到 ...

你居然不沐浴更衣焚香净口后再念.．．．一口污浊之气.．．生生玷污了瓜教授名言.．．．

作者: KuoiGuaBoarder 时间: 2015-12-18 18:14
你们也太能作践人，咱现在发现自己理论一窍不通，经常被大侠说的云来雾去的。

想开开心心，安安全全滑个雪，咋就嫩难呢

作者: 常hold的住 时间: 2015-12-18 21:19
入风大侠V5

作者: 常hold的住 时间: 2015-12-18 21:22
偶赶脚 TFR就是ILS.
不过是老怪会营销，换了个说法。

作者: 常hold的住 时间: 2015-12-18 21:56

如上图，在一个有内倾的合格回转中，重心转过的角度是小于双板/双腿转过的角度。也就是说不管是卡宾弯还是pivoting，一个回转中都应该有ILS。只不过一个被动，主动。
被动技术被老怪演绎成主导了。

被动的技术一定要有外力来启动，所以偶们看到老怪的BPST视频多有点杖，需要靠Blocking补充角动量。而这个角动量，xSIA可以由大腿来提供。

作者: cat 时间: 2015-12-18 22:11
神马？！这样牛逼的帖子居然没有置顶？！我很想放到签名档里，可是签名档不够地方，怎么破？

常大侠楼上的回复让此帖内涵又上升了了一个层次，眼瞅着滑雪届一个又一个的大秘密被你们这样毫不留情地戳破，我很为指导员这个群体的未来担忧啊！

啥时候有雪啊？我也要去试试看，外板高速滑行，内板板头猛然插到雪里，刷，一个弯，九浅一深，插，插，插... 想想都美啊

作者: bullpower 时间: 2015-12-19 09:19

cat 发表于 2015-12-18 22:11
神马？！这样牛逼的帖子居然没有置顶？！我很想放到签名档里，可是签名档不够地方，怎么破？

常大侠楼上的 ...

盐多必湿
你是安省G T A的

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