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TABLE TENNIS OVERVIEW History: Table tennis was invented in the late nineteenth century in England and was originally called Ping Pong. It acquired worldwide popularity as an after-dinner pastime thanks to the widespread influence of the British Empire at that time. The craze was rather short-lived, however, and the game was played little between 1904 and 1922. New interest in the activity, coupled with improvements in paddle design, led a group of Englishmen in the 1920s to unify the rules and to adopt the name of table tennis. The first international championships were held in 1926, the same year the International Table Tennis Federation (ITTF) was founded. Lady Swaythling organized this first international tournament for the cup that still bears her name. Table tennis today rates as one of the world’s largest and most popular participant sports. It is not too surprising considering it is usually played indoors, it is played by both sexes and the equipment is relatively inexpensive, except for the table. Also, the game remains essentially simple in spite of the technology of spins, paddle surfaces and padding, etc. The historical game started with champagne corks for balls and cigar boxes for paddles. Then they progressed to rubber balls and wood surface paddles (bats) by the late nineteenth century. Finally, these gave way to the light celluloid ball and the rubber-pimpled paddles that gave table tennis a new dimension of speed and spin. Synopsis: Table tennis is an indoor ball game for two players (singles) or four (doubles). The players use paddles to hit a small resilient hollow ball back and forth across a table divided by a low net. The object is to win points by making shots that an opponent is unable to return. Play commences with a service, after which each player hits the ball directly over or around the net so that it bounces in the opponent’s court. Volleying is not permitted. The rallying ends, and the point is won by the opponent, when one player fails to return the ball after the first bounce. The first to score 21 points, or to have an advantage of two points if the score reaches 20 points each, wins. Service alternates after every five points. In doubles, the service is made from the right-hand half-court to the half-court diagonally opposite, after which the four players hit the ball alternately. After five points, the receiver serves to the previous server’s partner. Other background sources: See the Rand McNally Illustrated Dictionary of Sports, pages 60-1, for some table, paddle and ball dimensions and technicalities. There are some good illustrations and most definitions of terms characteristic of this sport are also included. See The Rule Book, pages 362-7, for the best review of the technical rules of table tennis, equipment specifications, etc. See Rules of the Game: The Complete Illustrated Encyclopedia of All the Sports of the World, pages 1201, for more good illustrations, rules, and technical information. See the Guinness Book of Sports Records, Winners and Champions, pages 306-8 for some interesting history, facts, and a roster of the game’s greatest players. TABLE TENNIS DICTIONARY OF TERMS See the Rand McNally Illustrated Dictionary of Sports, pages 60-1, for most basic definitions. VISUAL SKILLS IMPORTANT FOR TABLE TENNIS Visual Acuity: Both static and dynamic visual acuity are important in the fast-moving visual sport of table tennis. Peripheral Vision: This is important in table tennis. Although most play is directed fairly straight ahead, the player must be peripherally aware of boundary lines, the ball at all times, the location of the table and net while returning a difficult shot that has him/her stretching to the sides of the playing area. Also, in doubles, the player has to be aware of the partner’s body and paddle to avoid interfering with their shots or even injury. Many eye fakes are done in table tennis where the player will be looking at one part of the opponent’s side of the table to get him thinking the shot will be going to that location, while in reality, the plan is to hit the ball to the opposite side of the table. Proper placement of shots like these requires good peripheral vision. Depth Perception: Necessary for table tennis in that most good players stand five feet or more beyond their end of the table. They must judge depth for proper placement of their shots onto their opponent’s side of the table. It is also critical for proper defense in that it helps in determining the velocity of oncoming shots from the opponent. Eye Motility: Eye tracking ability is critical in table tennis. Quick, accurate saccades help survey the playing area for potential weaknesses in the opponent’s defensive position, relative relationships between the ball, paddle, boundary lines, net, etc. Obviously, there can be considerable convergence and divergence eye motility work during the course of a table tennis match and all this is at a high speed. For example, in the Guinness Book of Sports Records, Winners and Champions, page 306, it discusses the world’s fastest rally. This was 162 hits in 60 seconds! Although you would certainly have a slower pace during a normal game, it still involves a lot of converging and diverging fine eye movement control. Eye-Hand/Body/Foot Coordination: All are helpful to a table tennis player’s performance. Most good players are not only quick with their hand and wrist, they are usually very fast on their feet and have excellent balance. Visualization: This could be useful in practice workouts for serious competitors and as a pre-match warm-up and post-match cool down. However, during actual rallies, table tennis is such a fast-moving sport, the player doesn’t have time to think and visualize using the normal five-step technique. He/She must simply react. The service might be a possible exception. Speed of Recognition Time: This is an important visual skill for a table tennis player to possess. A kill shot in table tennis might attain speeds of up to almost 106 m.p.h. This does not leave much time for the defensive player to respond. It is also useful in picking up directions of spin on the ball. Speed of Focusing: This is also important in table tennis because the ball and other players (especially in doubles matches) move quickly. One has to be able to shift focus from near to far or intermediate targets rapidly throughout the contest while general body stamina is running down due to heavy exertion. Glare Recovery Speed: This visual skill can be of some use in table tennis because the ball is white, small, and moving at high rates of speed and with tricky spins. The actual international rules try to prevent players from having glare recovery problems in the following ways: 1. The playing surface is specified to be dark in color, preferably green, and with a matte finish. This improves contrast with the white ball and reduces glare off the table from overhead lighting. 2. Dress code for players specifies no white clothing, though white edging on playing shirts is permitted. Match uniforms usually consist of a dark shirt, shorts or skirt. This helps the defensive player not lose the white ball momentarily against the background of the white shirt of the offensive player. Because of these considerations and rules, glare recovery is not as important a problem in this sport as it could be. Ability to See in Dim Illumination: Not a big factor in table tennis because most games are played indoors with pretty good lighting. Ability to Withstand Eye Fatigue Without Decreased Performance: This can be important in table tennis, especially during long tournaments with up to five games per match. Even under the expedite system, which keeps matches from dragging on and on, players can become quite fatigued. Color Perception: Color is used in table tennis mainly as a dark background for the white or yellow ball. This is true for table colors, paddle colors and clothing allowed on the players. Otherwise it isn’t terribly critical to a table tennis player’s performance. Eye Dominance: Of some interest probably, but not as critical a factor in this sport as in baseball hitting, rifle shooting or archery. Fixation Ability: This needs to be very quick and accurate in table tennis. It can also help in placing shots in the opponent’s court accurately during the follow-through stage of a shot. The player should be taught to fine-center on the smallest possible detail on the table surface when placing these shots. Visual Memory: Past experience and the number of proper shots, spins, fakes, serves, etc., on file in the visual memory, combined with some good visualization techniques, for serves particularly, could be a factor in the steadiness and consistency of a table tennis player. Central/Peripheral Awareness: This is an essential visual skill for a good table tennis player. On offense or defense, you have to be aware of the ball particularly; but you also have to be aware of where on the table you want to place your next shot, where your paddle is, and in doubles, where your partner is while playing a shot. Spatial Localization: Knowing where you are relative to other objects is very important for good table tennis. This is such a fast-moving sport, the athletes, ball, paddles, and in doubles, the teammates are all in motion at once. Although the table and net are stationary, the table tennis player is often running or leaning to reach the ball and return it properly relative to that stationary table and net. VISION SCREENING/TESTING PROCEDURES INDICATED FOR TABLE TENNIS PLAYERS Visual Acuity (Static and Dynamic) 1. Normal Snellen 2. Vectographic 3. Autorefractor 4. Record player with visual acuity disk at three speeds (33, 45, 75 rpm) 5. Tachistoscopic Acuity Peripheral Vision Dicon, Synamed Fieldmaster, etc. Depth Perception 1. Randot - distance 2. Stereo Circles - projected at distance 3. Stereo Fly - near 4. Randot - near 5. Consider timing the testing on the Randots Eye Motility 1. Eye Track a. This quantifies graphs on paper b. Good for before/after studies c. Athletes and coaches can see if progress has been made 2. Wayne Saccadic Fixator a. Pursuits b. Saccades c. Rotations Eye-Hand/Body/Foot Coordination 1. Wayne Saccadic Fixator a. Normal use with the hands b. Footboard use, which brings in the table tennis player’s balance. 2. Strobe Light - Creates more visual noise, so the athlete has to learn to concentrate more Visualization 1. No specific testing 2. The principles can be taught and trained, however. Speed of Recognition Time 1. Tachistoscope 2. Computerized Anaglyphic Trainer Speed of Focusing 1. Wayne’s near/far fixation module (in 30 seconds, a good score = 15) 2. Flippers (for near only) +/- 2.00 D (2 seconds = normal response) Ability to Withstand Eye Fatigue Without Decreased Performance 1. Ask the table tennis player (or their coach) whether he/she is a consistent performer throughout the game. 2. Do a complete evaluation of all pertinent visual skills before and immediately after a match or hard practice session to compare. Fixation Ability 1. Eye Track 2. Dicon perimeter, which beeps when the subject loses fixation. Visual Memory 1. No specific testing 2. The principles can be taught and trained, however. Central/Peripheral Awareness 1. Wayne Saccadic Fixator with “stick-ups” and gun you fire at the light a. Mode 1 = 15 or greater = good b. Mode 2 = 5 is pretty good 2. Dicon or Synamed Fieldmaster Spatial Localization 1. Phorias a. Base-In 2. 3. b. Base-Out Brock String Computerized Anaglyphic Trainer VISION TRAINING TECHNIQUES INDICATED FOR TABLE TENNIS PLAYERS 1. Visual Acuity Keep the athlete in current glasses/contact lenses for best visual acuity if an Rx is needed. Soft contact lenses are usually the lens of choice for this sport, but firm lenses and glasses are also used quite frequently when soft contacts are ruled out for some reason. 2. Peripheral Vision a. Awareness of peripheral vision can be enhanced (see under central/peripheral awareness). b. If a visual field defect is present, the table tennis player can be counseled as to how to compensate by orienting his/her game toward negating the weak point. 3. Depth Perception Stereopsis is the ultimate of good binocularity. So train binocularity (BI and BO reserves) and stereo should improve with enhanced visual functions. b. Red/Green Sports Tranaglyphs from Bernell can help build ranges. a. 4. a. b. c. d. Eye Motility Peg board rotators Arneson Corrector (Audio Feedback mechanism) Computerized Anaglyphic Trainer Wayne Saccadic Fixator 5. Eye-Hand/Body/Foot Coordination a. Wayne Saccadic Fixator 1) Normal use with the hands. 2) Footboard use helps train the table tennis player’s balance system in response to the visual signals he/she is getting off the board. b. Strobe Light - A table tennis player trying to rally under strobe light practice conditions has to concentrate more due to the increased visual noise. 6. Visualization An example will be given as to how to use the principles of visualization for enhancing a table tennis player’s serve. a. Analyze: Look at the opponent’s defensive position and scan the table for the spot you would like to place your serve to score your ace. b. Visualize: Precede your performance with a visual picture of the desired action. Fine tune visually (center) on the spot on the table you want your serve to hit. Don’t stare. Just pick it out and see it in your mind’s eye. Follow the trajectory of your serve from the ball being tossed up from its starting position on your flat palm. Visualize the type of spin you want to put on the ball as it begins to fall (top spin, backspin, low-flight chop, etc.). Try to see all the components of a good serve in slow motion in your mind. This is visualization. Follow the trajectory of the ball across the net to the predetermined position in the receiver’s court that you wanted. See the ball hit the table and the effect of whatever type spin you put on it alter its direction past the opponent for the ace. All these steps would be visualized quite rapidly. c. Center: Fine center on the smallest detail of the receiver’s court you can use for your target. Develop a solid awareness of the target, but don’t stare at it for a long time before serving. d. e. Make the fine centering a very brief concentration on your target. Execute: Perform your serve first, watching the ball as you toss it in the air. Then, as the paddle is making contact with the ball, shift your focus to your target on the receiver’s court. Follow through with arm, wrist, leg and body thrust to develop power in the shot. Direct all that energy toward that tiny, fine focus point you are centering on for that particular serve. Playback: This can be done after each serve in practice sessions (both good and bad). It would be pretty difficult to do after every serve in a match because of the speed of these games once the rally begins. But good servers are made in practice — not games. And the playback portion of the visualization sequence can be used extensively in practice sessions to develop one’s serving. Playback is visualizing the complete sequence of steps in making or missing your serve again and reviewing all the visual images you centered on. This will help to reinforce whatever there was to learn from that shot (good or bad) for future visual memory. 7. Speed of Recognition Time a. Train this visual skill with the same instruments used to measure or test this skill. b. Instruments 1) Tachistoscope (Targets = shapes, tic-tac-toe, numbers, letters, etc.) 2) Computerized Anaglyphic Trainer 3) Make progressions for your table tennis athletes from easy toward most difficult. 8. Speed of Focusing a. Red/Green anaglyphic accommodative rock b. Wayne Saccadic Fixator c. Flippers 9. Ability to Withstand Eye Fatigue Without Decreased Performance Use the five steps of visualization on all serves to enhance concentration and give the table tennis player a definite plan of attack for at least that part of his/her game when fatigue is becoming a factor. This is very helpful in pulling the athletes through a match even when they are tired and at a low emotional level. It should help establish consistency so the table tennis player won’t be so erratic. 10. Fixation Ability Counsel the table tennis player to fine focus (center) on the smallest possible targets on the receiver’s court whether serving or just returning shots during a rally. b. The shorter the amount of time the player fine focuses on the target, the more intense the focusing ability will be. a. 11. Visual Memory This is where the playback phase of visualization (Step 6e) pays big dividends. It helps you build his/her frame of reference. b. Later they can use this frame of reference to visualize the things they have done to succeed in the past under similar circumstances. c. The Memory Book by Jerry Lucas is a good reference book for understanding and applying principles of visual memory more fully. a. 12. Central/Peripheral Awareness a. Wayne “stick-ups” are good for training. b. As you go about your day, just concentrating on how much detail you can gather from your periphery without actually looking over at the details directly (with central vision) is great training for this visual skill. 3. 13. This skill isn’t something that is developed overnight. You have to work at it daily until you’re good at it. The skill should transfer well to your table tennis game, however. Spatial Localization a. Train with the same instruments and equipment you use to measure and test this skill. b. Instruments 1) Brock String (in all 9 positions of gaze) 2) Computerized Anaglyphic Trainer SPORTS VISION PROBLEMS/SOLUTIONS RELATED TO TABLE TENNIS Problems Solutions Safety Risks: Probably a ball in the eye from an opponent’s kill shot, an elbow from a doubles partner or a partner’s paddle in the eye are the most serious eye-related injuries likely in table tennis. Protective goggles could be used as the ultimate protection against corneal abrasion and most trauma. Even a soft contact lens could be a protection in the event of a ball in the eye (as the ball is so light weight). Eye injuries aren’t as serious or numerous in this sport as in racquetball, mainly because of the weight of the ball. Vision Correction Needed: Playing table tennis with blurry vision could decrease performance. Contact lenses are best for table tennis, although many players requiring an Rx wear glasses. Soft contacts would be the lens of choice, if possible. High Velocity Projectiles: A table tennis ball can travel at speeds of almost 106 m.p.h. Because the table tennis ball is “eyeball size,” the orbit doesn’t protect from trauma. The speed of this game is just part of the risk. Fortunately, the ball is very light weight. Fogging Of Glasses: This is a vigorous sport and drops of sweat on the back of a player’s glasses can be a problem. A sweatband around the forehead can be helpful. Anti-fogging compounds are also useful. Contact lenses can solve this problem. Playing with Only One Usable Eye: Some visual skills will be reduced in a monocular or amblyopic player. The chance of losing the other eye in table tennis isn’t a high risk. The player and his parents should be advised that there is some risk, although not great. PROTECTIVE/CORRECTIVE EYEWEAR FOR TABLE TENNIS 1. 2. 3. 4. Polycarbonate glasses and/or goggles Sports straps for glasses Firm contact lenses - preferably gas permeable if the player cannot be fit with soft lenses; also colored lenses for easier location if they are dislodged during a game. Soft contact lenses - the corrective method of choice for most table tennis players MOST COMMON OCULAR INJURIES SUSTAINED IN TABLE TENNIS Corneal abrasion Trauma to the globe from the ball, a doubles partner’s paddle or body, with subsequent secondary complications Lacerations around the orbit, lids, or globe itself EMERGENCY FIRST-AID FOR OCULAR INJURIES SUSTAINED IN TABLE TENNIS Trainers should be taught how to perform the following: 1. Proper lavage and rinsing of an eye with a foreign body 2. Instillation of ophthalmic drops 3. Application of a proper lubricant to an injured eye prior to application of a pressure bandage 4. Handling of contact lenses (hard and soft) and removal of them from the eyes OCULAR SUPPLIES FOR THE TABLE TENNIS TRAINER’S FIRST-AID KIT Sterile saline eyewash Artificial tears Q-tips DMV (hard contact lens remover) Fluorescein strips Black light penlight Regular penlight Polysporin ointment Oval eye pads Dermacel tape 1” Spare contact lenses for all players wearing contact lenses (properly labeled) Trial size bottles of storage/disinfectant solution for contact lenses Some butterfly tape strips to hold lacerated skin areas together Small mirror TABLE TENNIS 2 MISCELLANEOUS COMMENTS 1. If you knew your athletic income could be over a million dollars over the next 10 years, would you be willing to remove any obstacles to improve your performance? 2. Vision is the dominant sense for table tennis and most other sports. 3. Five times as much brain cortex is related to vision as all other senses combined. 4. As much as 80% of all information reaches the human brain through the eye gate. 5. 80% of the optic nerve fibers connect directly to the cortex. 6. 20% of the optic nerve fibers connect to balance and posture control centers in the brain. REFERENCES 1. Diagram Group. Rules of the Game: The Complete Illustrated Encyclopedia of All the Sports of the World. New York, NY: Paddington Press Ltd, 1974:120-1. 2. Wright G. Rand McNally Illustrated Dictionary of Sports. Chicago, IL: Rand McNally & Co., 1978:60-1. 3. Diagram Group. The Rule Book. New York, NY: St. Martin’s Press, 1983:362-7. 4. McWhirter N. Guinness Book of Sports Records, Winners and Champions. New York, NY: Sterling Publishing Co., 1980:306-8. 5. Barnes C. Advanced Table Tennis Techniques. New York, NY: Arco Publishing Co., Inc., 1977. 6. De DS, et al. The Chinese Book of Table Tennis. New York, NY: Atheneum Publishers, Inc., 1981. 7. Harrover G. Table Tennis. London, England: The English Universities Press, LTD, 1966. 8. Leach J. Table Tennis for the Seventies. Cranbury, NJ: A.S. Barnes & Company, 1971. 9. Miles D. The Game of Table Tennis. Philadelphia, PA: J.B. Lippincott Company, 1968. 10. Philip D. Table Tennis. New York, NY: Atheneum Books, 1975. 11. Squires D. The Other Racquet Sports. New York, NY: McGraw-Hill, 1978 12. Elmurr P, Cornell E, Heard R. Quantitative analyses of horizontal saccadic eye movement: Reaction times to table tennis players and non-athletes. Int J Sports Vision 1996;3:46-53. 13. Elmurr P, Cornell E, Heard R, Kenny F. Do table tennis players have better eye movements? Australian Orthoptic Journal 1994;30:49-54. 14. Hughes PK, Blundell NL, Walters JM. Visual and psychomotor performance of elite, intermediate and novice table tennis competitors. Clinical and Experimental Optometry 3993;76:51-60. 15. Ripoll H. Uncertainty and visual strategies in table tennis. Percept Mot Skills 1989;68:507-12. ©1998 American Optometric Association