Free Forehand

August 9, 2018 | Author: jose li | Category: Table Tennis, Sports, Leisure, Nature
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This ebook is about mastering your tennis forehand...

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Free Forehand  Dr. Jose Li (www.adhd-tennis.org)

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Less Le sson on 1: Manage Manage mind mind and arm arm fir first st The average ball flight time for an 80-mph forehand is about 1.3 seconds. At the end of the flight time, when the ball bounces forward, the receiver needs to respond to the ball by: 



reacting (human beings' reaction time is about 0.2 seconds) acting in multitasks (e.g., grip change, hit zone setup, and ball strike).

The mind's path in ball striking follows the "3C" sequence. In about a 1second time span, as a process: Consider (requiring sound judgment), Converge (requiring good habits) and Concentrate (requiring discipline). Below figure illustrates my converging mind mind pyramid, which explains explains the mind target in a dynamic dynamic fashion.

In the last 1/200th 1/200th of one second second (~5ms) (~5ms) at contact, contact, when the ball ball is fully fully compressed, our eyes cannot see the ball on the sweet spot, but our minds can "see" the ball impacting the racquet by imagination and sensation. If our  eyes are busy to radar everything (called (called "bouncy eyes") eyes") on court, our mind  our mind  cannot cannot guide to time the the ball right. right.

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Tennis play is done by arm and hand with the racket. However, arm and hand are “trouble “trouble makers” in in most cases. Let us fix these these “trouble makers” makers” first. “Great “Great Wall stance” stance” is about about the arm/racket arm/racket position position to receive receive ball at contact in forehand. This stance with two two 90 degree bents between arm and racket focuses on the shape of hitting arm to support the racket contacting to the ball. It serves serves two purposes: purposes: 1) Keep the racket face face vertical; and 2) support the the ball hitting hitting to the sweet spot of the racket.

The “Great Wall” is a kind of buzzword reflecting the key meaning of this stance: the body support support has to be as stable stable as the Great Wall! Wall!

To achieve those two 90 degree bents with desirable orientation of your  racket relating to the forearm, the two common instructions are: (1)Relaxing muscles in upper arm and shoulder, too much tension with st tight muscles cannot achieve 1  bent  bent (in arm arm). (2)Keeping the wrist “laid back” and locked at contact for forming the nd 2  bent (in hand/rack hand/racket). et).

You can see the “GWS” is nothing new but highlighting the importance of  the body stability behind the ball at contact. Let us create create a visualizat visualization ion image image in our minds with this this “GW “GWS” S” shown shown  below:

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Tennis is NOT about swing racket to the ball simply because of one reason: tennis is NOT baseball! In high-level tennis, skill of “waiting” the ball is even more effective than “chasing” the ball. In Chinese martial art, “standing still still and straight” is taught taught first before any movements are taught. taught. Swim coaching also starts starts with body balance instructi instruction on first first (see shark shark fin stance stance photo below) below).. Stance, Stance and Stance.

That is why we should learn this static stance first in forehand.

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Less Le sson on 2: Con Contact tact,, the core core of of ten tenni niss Great Wall stance stance (GWS) (GWS) is for a solid solid contact contact between between racket racket and and ball. ball. The contact is the “core” of of tennis. Every thing thing is for THIS moment, which which normally takes ~ 1/200 seconds. We address arm/hand position first, than to racket/ball interaction at contact. contact. Understanding racket/ball interaction interaction can make learning new forehand forehand more “meaningful”. Below photos show this this kind of interaction interaction right right before before and after the contact as well as in the forehand contact.

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Those three factors controlling forehand quality, the pace (mph), spin (rpm) and ball striking angle are determined after contact. When we know how to make the right contact in play, we can make our shots more powerful and controllable. In forehand, there are 7 stroke keys in a hitting sequence: body turn, align racket cap to the ball, pull the racket, contact, lift and push the racket, wipe and follow through finish. I believe that the contact stroke key key should be taught first. first. Other stroke keys are just designed for making better contact in a more repeatable fashion. Our  tennis coaching should follow this logic path.

What else can we learn from this contact stroke key? From high-speed video visualization analysis, we can study how tennis pro hits to contact. There are two two important features features in this contact contact phase: a) Racket Racket and ball ball meet meet vertical vertically ly at contact; contact; and and  b) Ball is is compress compressed ed at racket racket sweet sweet spot. spot. It happens in 5 ms, or 1/200 second, which cannot be clearly seen by human eye. Below Below photos photos show this critical critical mome moment nt (taken by 210 210 fps digital digital video): Ball is compressed! It can “stick” to the racket for a prolonged time. This is a simple concept for  improving control. The question is how to get ball ball compressed?

If we look at those forehand shots generated by tennis pros, we can find the following commonalities: commonalities: a) Racket Racket in verti vertical cal orie orienta ntatio tion n

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 b) Hit ball ball on on “swe “sweet et spot” spot” Vertical al and and swee sweett spot spot contac contact’  t’  is easy to say, but difficult to do. “Vertic “Vertical” is the only 1 of 360 degrees the racket orientation needs to be   positioned; and and sweet spot spot is only small portion portion of racquet face. To meet   both requirements at the same time, time, it is even harder! harder! The most common common coaching is: Look the ball at contact!

Wait a minute; can Federer really see the ball at contact? Does it make sense to look the contact to see what really happens during the mind (not your eyes!) eyes!) contact in 5 ms? The answer is yes as long as your mind is on the ball during the impacting. For most of players, players, it is easier to look at the ball than mind the ball at contact. Federer Federer does see the ball ball at contact contact (with his mind). mind). If other other players players feel the  ball by their minds even though they do not look at the ball, they still can hit a clean shot. For a better contact, a pro normally trace the coming ball with his eyes up to the hitting zone. I believe that Federer gazes the ball at contact contact not because he can see see the ball ball in 5 ms. ms. His His secret secret is that that he keeps keeps his head head “static” “static” at contact contact so that his whole body body maintains maintains a stable stable position. position. This static head position at contact is Federer’s signature post.

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Lesson Lesson 3: Seven Seven Stro Stroke ke Keys Keys in in Forehand The seven stroke keys in forehand are: are: a) Body turn; turn; b) align racket racket cap to the ball; ball; c) pull and and torque the the racket; racket; d) contact the ball; ball; e) lift and push the the racket; f) wipe/brush wipe/brush and g) follow-through I summarize those stroke keys in a pyramid based on 3 critical concepts addressed in lesson 1 and 2: mind, stance and contact

Jose's forehand coaching system (TM)

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At beginner beginner level, level, I coach forehand forehand as “1-2-3”: “1-2-3”: turn - contact contact - follow follow through At intermediate intermediate level, I add 2 more keys in forehand forehand as “1-2-3-4-5”: “1-2-3-4-5”: turn –   point  point – contac contactt – wipe wipe – follow follow throug through h At competitive level, all 7 keys need to be addressed as “1-2-3-4-5-6-7”: turn turn – poin pointt – pull pull – cont contac actt – push push – wipe wipe – foll follow ow thro throug ugh h Remember, contact is most important stroke key. Other stroke keys are designed for achieving a better contact. Below I create two drills to practice forehand forehand for improving improving pace, timing timing and and spin control: Level 1 drill: focusing on on leg stance and body weight transfer. Level 2 drill: focusing on shoulder shoulder turn and hand hand orientation. orientation. Level 1: hit high ball with pace (80mph) in forehand

turn

contact

follow-through

In this level, basically just follow Dr. David Porter’s instruction as: load –  explode explode – land, which are are done done in keys: keys: turn turn – contact contact - follow follow through through

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In the load mode, body weight is on the inside of outside leg. In the explode mode, jumping helps to hit ball at high zone. In the land mode, body weight shifts to another leg. leg. Two distinctions are a) body is always in balance in these three modes; and b) body weight moves forward to help generating  power. There is a wrong wrong perception that open stance forehand forehand only addresses body angular move rather than than linear forward. forward. If you use the yellow “+” as a reference, you can see the body moves forward “a lot”! Level 2: hit high ball early with pace in forehand

point/pull racket butt

contact

windshield/wipe

In this level, timing timing is added into consideration consideration in training. training. Rather than swing to the ball, which has poor timing, racquet cup pointing and pulling toward the ball “until the last second” is the key. Shoulder turn is the main element in this level. 180 deg turn can be seen: front shoulder “eye” the coming ball before contact; and back shoulder  “eye” the leaving ball after contact. The follow-through has two key elements: a) racket windshield with a wiping motion; and b) shoulder turns nd the 2 90 deg. nd

In shoulder only turns 90 deg to the contact (without 2 90 deg turn), hitting arm has to go around the head to provide energy outlet.

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Lesson Lesson 4: Catch Catch and Thr Throw ow When ball is compressed, you can throw it forward with better control. However, a ball might not be easily compressed if not hitting to the sweet spot. Swing too much leads to mis-hit. mis-hit. Baseball type type of swing is very harmful here. here. If you do like to think any synergy synergy between baseball and tennis, try to link baseball receiving rather than batting to this “catch” in contact. So forget about “Swing back then Swing forward”  to the ball, try to use Great Wall position (stance) to “Catch then Throw ” the ball. Better  contact can be trained by simply changing the mindset, the way to think  about the contact. In any sports, imagination is needed especially in speedoriented sport. When When hitting hitting to contact, imaging the “Lacrosse” “Lacrosse” as as a “Catch” and “Frisbee” as a “Throw”. If you use western grip, Frisbee throw is a good drill.

Below photos show how Federer does his free forehand by “catch and throw”: he does not swing swing his racket backward backward then forward!

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Below drill is to help to “forget about swing” and achieve “catch and throw” in forehand:

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Forearm rotation

contact

Catch

brush/push

Throw

Trunk (hip) internal rotation is under looked in forehand instruction. However, this part is the “core” in kinetic chain as a linkage between legs and upper upper body. body. It does the critical critical job to generate generate power. power. Adding topspin requires extra energy energy (inverting spin and increasing increasing high rpm). Trunk turn is the key! When we say, “hit the ball”, it does not mean, “swing to the ball”, it means “rotating the forearm to catch the ball at sweet spot”. To generating topspin, no no racket “roll-over”! “roll-over”! Instead, “brush the ball up and  push the ball forward” do the job. This job can also be called “throwing “throwing the  ball” (after catching).

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Less Le sson on 5: Tops Topspi pin n fore foreha hand nd

Professor Howard Brody, author of “Tennis Science for Tennis Players” tried to quantify the margin of errors by using a term called “vertical angular  acceptance”, which is defined by the angle difference between two ball trajectories limited by net height and baseline. He studied the correlation  between the forehand speed and margin of error (shown in a figure below). Fastball tents to have fewer margins of error. error. Practically speaking, the vertical angular acceptance has to be >= 5 deg for most of players so that the margin of error can be manageable.

Topspin is the major solution to improve the margin of error without compromising ball speed. Tennis racket and ball contact is the primary source to generate spin. Does racket “roll over” at end of contact practical in topspin forehand?

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300 years ago, Newton saw that a tennis ball (not the same tennis now) “struck with an oblique racket" would curve with spin. Borg was one of the first top players to use heavy topspin on his shots consistently. Borg used to discribe his topspin forehand as following: “…I snap my wrist upward in a sweeping motion rolling the racquet face over over at the end of contact and carrying the racquet over my left shoulder on the follow-through follow-through often so it is pointing directly directly behind behind me. The secret of  my forehand is dropping the racquet head below the ball so that upward swing can produce wild topspin. No golf hip forward. I do sacrifice depth by my heavy emphasis on spin, but I think consistency is more important, not hitting over the base line nor hitting into the net…” Racquet face rollover sounds like a secret weapon in Borg’s topspin forehand.

That “rollover” effect at the end of contact is considered to “prolong” the contact between racket racket and ball. However, it not commonly seen in

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Federer’s topspin forehand at all. all. tennis, but not practical in tennis.

It might be seen in Ping Pong table

The most common topspin stroke key is “brushing up + pushing forward” at the end of contact to to right after the contact. See photo below:

Actually, the more tilting down your racket, the worse in net clearance. clearance. If  the racket is tilted to 90 deg as the extreme case like “rollover”, the ball trajectory will look unfavorable, which totally defeat the purpose of topspin advantage in forehand. We can consider the racquet tilting as the early form change in the followthrough phase phase after contact (not during the contact). contact). For instance, instance, the racket is already already tilted tilted when when we do do “winds “windshield hield”” motion. motion. In other other word, the racquet face is tilted very late rather than during the contact. However, we normally do not call it as racket “tilting” or “roll over” as an extreme in the follow through phase AFTER contact. In this phase, our eyes might be fooled that some players are doing racket “roll over” since the ball striking speed is so fast. Their racket is already out of contact of the ball. The racquet face orientation moves like we are wiping the car window in forehand follow-through simply for one biomechanical reason: kinetic energy needs an outlet after firing the strike on the ball.

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Lesson 6: Racket orientation Below photo shows a common racket orientation seen in recreational tennis. What is wrong with this racket orientation?

Power comes comes from the body kinetic chain chain in forehand. forehand. The ball striking striking comes from the forearm rotation impacting to the ball at contact, not from the simple racket swing. swing. Racket swing swing does not provide the power. It messes up accuracy and consistency as well. We know big racket swing (back and forward) does not help timing. Actually, timing the contact is very difficult when both racket and ball are in moving towards towards to meet the desirable location and angle. The practical solution is to rotate forearm rather than swing the racket impacting the ball. By doing this, let racket more close to the coming ball then do striking: we have more more time time to act. The key instructions are:

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(a) Let hand and racket butt leads the racket racket (racket head is trailing) before forearm rotation to the contact (b) Our body can be in the “load” mode early, early, but hold the forearm forearm rotation until last second to trigger impacting the ball. Based on these new concepts to improve timing for accuracy and consistency in forehand, we address the following stroke key as “point and  pull” of the racket butt. After studying tennis pros forehand stroke keys, one commonality is seen: they point the racket butt to the coming ball even the ball is just about to  bounce to the hitting zone. This stroke key is independent of racket grip and standing stance. This racket orientation was used by tennis legend 50 years ago when a combination co mbination of continental grip and open stance is seen in below  photo.

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To help players build build visual images in forehand, a useful drill with flash bar  can be practiced (see photo above). In the game, players normally point the coming ball with the racket butt until the ball is so close to the racket butt. They do not rush to rotate the forearm hitting to contact contact until last last moment. This type type of “delay” helps players to have better control: aligning, pulling and then hitting to contact at sweet spot.

How about the racket orientation after contact, e.g. in the phase of followthrough? Let us discuss the racket orientation in “reverse “reverse forehand”. forehand”. If Nadal hits high ball forehand in the clay court, you will see lots of  “reverse forehand”. forehand”. His racket is just just turning around around above his head rather  than around his shoulder shoulder after follow-through. This is his way to deal with high ball (or far ball) when his body is not in perfect balance position.

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High and far ball can put the receiver in a defense position at an “emergency” condition. This player might not have time to adjust your  footwork well, e.g. no time to put your weight on the inside of the outside leg in the open stance. stance. From biomechanical biomechanical point of view, if the body is not in a good balance position when hitting a high or far ball right after contact, nd it is very hard to have shoulder turned (I mean the 2 90 degree shoulder  turn). If using normal follow-through with the shoulder shoulder turn, turn, the player  might fall down the ground when body is not in a balanced position. However, the kinetic energy after hitting to the contact has to find its outlet. The major differences between open stance forehand and reverse forehand are highlighted in terms of kinetic chain (shoulder in green/trunk in grey vs. hitting arm position in the follow-through phase) in the photo below. nd Without 2 shoulder/trunk turn, it is relatively easier for player to recover  quickly to deal with next return. return. Reverse forehand might not be over-used in forehand routine since it is still considered as an “emergency” shot for most  players.

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Without turning the shoulder (after (after contact), Nadal is simply facing facing the net,  but having his hitting arm turning a circle above above his head. That is why lots of “reverse forehand” is seen on his forehand when he tries to hit high and far ball. Below photo shows how Nada hits high ball hard with heavy topspin. He does this with good reasons. reasons. He is forced to do “reverse “reverse forehand” not for the purpose of generating more power.

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Less Le sson on 7: Foot Footwo work rk in foreh orehan and d What is is Federer's Federer's top top secret secret in his his forehan forehand? d? Not the way way he hits hits the ball, ball,  but the way he approaches the ball... It is his footwork making THE differences: Federer experts his power from the ground up.Grace stems from player’s awareness of feet and the way movement flows from there: move easily in balance… like a ballet dancer, gliding above the court… Artful footwork means: means: - using crisp, crisp, tiny and deliberate deliberate steps - using long, long, loping loping strides strides - move more laterally laterally,, than vertically on court court

Elevate

lateral move

flexed leg push

abrupt heel-toe

weight transfer

jump to hit

Federer's footwork: artful and efficient efficient (from Geoff Macdoald, Macdoald, New York Times 8/31/09)

Two phases in approaching the ball: 1) reaction and 2) action 1) reaction: reaction: - when his his oppone opponent nt start start to hit the the ball, ball, Federer Federer elevates elevates (1st body reaction) - when deciding deciding forehan forehand d or backhand, backhand, Federer Federer start start lateral lateral move on his foot (2nd body reaction) 2) action: action: - positioni positioning ng for for the the shot shot by flexed flexed leg push - mantaining mantaining good good body balance balance by exagger exaggerated ated heel-to heel-toee motion motion

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- smooth smooth weight transf transfer er and jump jump to hit ball ball by kineti kineticc chain Using boxing to explain explain the role of footwork footwork in tennis is a very interesting approach. Mike Agassi, Agassi, an Iran's former boxing champion, champion, passed down his   boxing boxing instinct instinctss and techniq techniques ues to his son, son, produci producing ng world world tennis tennis champion, Andre Agassi. “Explode” is commonly used in modern tennis. In open stance forehand, three phases “load, explode and land” are used in coaching forehand. This   body “explode” is relating to racket “acceleration” by kinetic chain. I will use a separate chapter to go through this topic in depth. What can a tennis player learn from from boxing? boxing? A lot! I just just highlight one: In boxing, no one-punch winner, random punching without setup can exposure your weakness here and there, creating anti-punching opportunities for your opponent. In tennis, we do not count on one “winner” point to win the point to avoid unforced error. error. Both sports sports need mental strategy strategy and shot shot (or punch) setup to win the point. In boxing, the "one-two combo" is a nickname nickname of jab and cross cross combo. combo. See photos photos below. below.

Jab

Cross

Boxers usually learn this combination before any other. The jab is designed to get the fighter in range while effectively blinding the opponent and hiding

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the cross, which is a longer punch that that will be slipped if thrown on its own. st The key strategy is to setup 1   punch for the 2nd  punch, and use “combo” rather than one punch to win the point.

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