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BADMINTON
Brian Shih, O.D.
Richard Wu, O.D.
BADMINTON OVERVIEW
History: The game of badminton can be dated as far back as the twelfth century of England in
the royal court. However, similar types of games were also being played by the royal families of
Poland, India, and China. But, the name of badminton comes from the estate of Badminton,
home of the Duke of Beaufort. Internationally, the Thomas Cup, named after Sir George
Thomas of England, was held every three years very similar to the Davis Cup in tennis and
players from all over the world competed against each other. Badminton was very popular in
Asia and considered a national game in many countries of Asia. The present world governing
body for badminton is the International Badminton Federation (IBF).
Synopsis: Badminton is played with a racket and shuttle on a court divided by a net. It can be
played by two people (singles) or four people (doubles). The court is 17' by 44' long for singles
and 20' by 44' long for doubles with equal halves and divided by a net of 5' in height from floor
to the top at the center of the net, 5'1" at the posts. The object is to hit the shuttle over the net to
your opponent without the shuttle touching the floor of the court. The game can be played both
indoors and outdoors. However, due to the weight of the shuttle, 73-85 grams, a slight breeze
can effect the flight path of the shuttle. Therefore, it is preferable to play indoors whenever
possible. The shuttle is not allowed to bounce on the surface of the court after being struck by
the players. A point will go to your opponent if your shuttle lands outside the court, or hits the
net without getting over it.
BADMINTON DICTIONARY OF TERMS
ABA: American Badminton Association, national governing body in the United States, founded
in 1936 (Now the USBA).
Alley: The 1.5' extension on both sides of the court used in doubles play.
Attacking Clear: A shot hit to barely clear the racket of your opponent and carry to the back of
his court. Sometimes called an offensive clear.
Back Alley: Area between the back boundary line and the long service line in doubles. This
area is 2.5' in depth.
Backcourt: The back half of the court in the general area of the back boundary lines.
Backhand: The non racket side of the body. For right-handed players this would be on the left
side of the body and includes all strokes made on this side.
Baseline: The lines parallel to the net which limit the playing area at the end of boundaries of
the court.
Base: The spot approximately in the center to which a player tries to return after each shot.
Bird: A commonly used term for the shuttle, the missile used in place of a ball.
Block: Placing the racket in front of the shuttle and letting it rebound off the racket to the
opponent's side of the court. Very little stroke is made.
Clear: Or also called Lob, a high, deep shot hit to the back of the opponent's court.
Combination doubles formation: A combination of the side-by-side and up-and-back
formations.
Court: Area of play. Standard size since 1930's is 20' by 44' for doubles and 17' by 44' for
singles.
Cross-court: A stroke hit diagonally from one side of the court to the other.
Deception: Deceiving one's opponent by changing the direction and speed of the shuttle at the
last second.
Double hit: Hitting the shuttle twice in succession on more than one stroke. This is illegal.
Drive: A hard, flat shot which makes a horizontal flight across the net. Usually hit close to the
net as it crosses and downward when possible.
Drive serve: A hard, quick serve with a flat trajectory. Usually used in doubles and aimed at
the opponent's head or left shoulder.
Drop: A stroke which just clears the net and immediately starts to fall in the opponent's court.
Fault: A violation of the rules. Faults can be during service, by both server or receiver, or
during play.
First service: A term used in doubles to indicate that the team still has both its serves.
Flick serve: Used in doubles when your opponent is expecting a low serve. A quick wrist and
forearm rotation changes a soft shot into a faster passing shot.
Foot fault: A violation in which the feet of the server, or receiver, are not in the position
required by the rules. This could be an illegal position and/or movement.
Forecourt: This is the area of the court nearest the net; usually refers to the area between the
net and the short service line.
Forehand: The racket side of the body. For right-handed players it would be the right side of
the body and including all strokes made on this side.
Game: The unit of points necessary to win the game. Fifteen points in men's single and in all
doubles constitute a game; eleven points constitute a game in women's singles.
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Game bird: The point that will enable the server to win the game.
Half-court shot: A shot played to midcourt, usually low, used in doubles and mixed doubles
against up-and-back formations.
IBF: International Badminton Federation, the world governing body founded in 1934.
Kill: A fast, downward return which usually cannot be returned.
Let: A legitimate stoppage of play due to interference from outside the court. It can be called
after a rally if a player or team served to received in the wrong court.
Love: A term used to indicate no score.
Love-all: A term which indicates the score is 0-0.
Match: A match is usually best two out of three games.
Match point: The point which, if won by the server, wins the match.
Midcourt: The center of the court area approximately halfway between the net and the back
boundary line.
Net shot: A shot played in the forecourt that barely clears the net and then drops rapidly. (See
Re-drop)
Obstruction: When a player hinders an opponent from playing the shot. Usually called if a
player who hits a poor net shot holds his racket up at the net and disconcerts his opponent, who
is trying to kill the poor shot.
Overhead: A stroke played above head height.
Racket: Or also called racquet, the implement used in the hand to hit the shuttle.
Rally: The exchange of strokes back and forth while the shuttle is in play until it becomes dead.
Ready position: The alert position that the player assumes just before the opponent strokes the
shuttle. It is usually with slightly flexed knees and racket held about chest high.
Receiver: The player who receives the service.
Re-drop: Stroke made from below and close to the net with the shuttle rising and just clearing
the net to fall sharply downward on the opposite side.
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Round-the-head-shot: A forehand stroke made on the backhand side of the body. Usually hit
overhead and can be either a clear, drop, or smash.
Rush the serve: Quick move to the net by the receiver after the serve has been struck to put
away a low serve that is weak. Used mostly in doubles and mixed doubles play.
Second service: A term used in doubles play to indicate that one person has lost his service and
is "down"; his partner still retains the serve.
Serve or service: The act of putting the shuttle into play by hitting it into the opponent's court.
Server: The player who delivers the service.
Service court: The areas into which the service must be delivered. This area will depend on
whether it is singles or doubles, and also depends on the score.
Setting: The method of extending the game by playing additional points when the score is tied
at specific scores in a game. The player or team reaching this score first has the option of
setting.
Short service line: The line 6.5' from the net that services must cross to be legal.
Shuttlecock: The official name for the shuttle or bird. The shuttles today are of three types,
goose feathers, duck feathers and nylon.
Side-by-side formation: A doubles formation used in either regular doubles or mixed doubles.
Smash: The hard overhead stroke hit downward with great force. It is the principal attacking
stroke in badminton.
Stroke: The action of striking the shuttle with the racket.
Underhand: A stroke which is made when the shuttle is contacted below the level of the
shoulders. It usually refers to a shot being hit upward.
Unsight: When the partner of the server stands in such a position that the receiver cannot see
the serve being struck. This is illegal.
Up-and-back formation: A doubles and mixed doubles formation.
VISUAL SKILLS IMPORTANT FOR BADMINTON
Visual acuity: Both static and dynamic visual acuity are important in the fast moving game of
badminton. It is very important to be able to see the bird coming and make split second
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decisions on where the player should hit the bird. Dynamic is even more important than static
because this is a constantly moving sport.
Peripheral vision: A necessary skill for winning the game. Especially in doubles where players
have to also be aware of the position of their partner and the boundary of the court at the same
time so the player's team can cover all the possible shots returned by their opponents.
Contrast sensitivity: Important to judge the location of the white color bird against the light
background like the ceiling of the indoor court. More important as the speed of the bird
increases when you play against more advanced players. The better the contrast sensitivity of
the players, the better chance for them to see the bird stand out against the background enabling
the players to locate the bird in space better and therefore anticipate the incoming or next shot.
Depth perception: Very important for accurate placement of the shots, and to judge the
distance and the speed of the bird. Also depth perception is needed for placing the bird at the
sweet spot of the racket while hitting to have maximum power. Good depth perception also
helps the player judge whether the shot is in or out of the court during matches.
Eye motility: One of the essential skills in badminton. Good quick, accurate eye tracking
ability both smooth and saccades are needed to follow the fast traveling bird. The ultimate goal
regarding eye motility and badminton is to track the shuttle until it actually hits the racket, not
flinching on impact.
Eye-hand/body/foot coordination: Important to develop good footwork and correct body
posture while hitting the bird accurately to gain maximum power on the bird. Also good
coordination will provide better reaction time during the game and prevent sports injuries.
Visualization: Since the game of badminton is very fast moving and requires fast reaction and
quick response time, it is very helpful to be able to visualize how players are going to play out
their next point before service so players can anticipate their opponent's next move.
Speed of recognition time: Badminton's rally shots travel at a very fast speed and with the
short distance between players, quickness in recognition time can help players anticipate and
prepare for the next rally returns.
Speed of focusing: Extremely important in badminton because the bird and other players are all
moving quickly and one has to be able to shift focus between near, intermediate, and far targets
throughout the game.
Glare recovery time: Somewhat important when the games are played outdoors, the players
must be able to recover fast from dazzling sun. However, due to the light weight of the bird,
most games are played indoors which generally diffuses lighting and therefore glare usually does
not pose big problems to most of the players.
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Ability to see in dim light: Not usually important because almost all the matches are played
under indoor situations with proper artificial lighting. Very few venues have the correct indirect
lighting required for badminton, as it is expensive to reconfigure or redesign lighting.
Ability to withstand eye fatigue without decreased performance: Important in badminton
because constant mental and physical concentration are required while the players are constantly
running and jumping.
Color perception: Color is not very critical to a badminton player's performance.
Visual memory: Past experience with visual memory and good visualization can improve ones
consistency and steadiness in playing the game of badminton.
Central/peripheral awareness: Essential visual skill because good players must be able to
localize their positions in the court as well as other players' positions in order to properly place
their next winning shot.
Spatial localization: Knowing ones position relative to other objects is very important, in such
a fast moving sport like badminton. The athlete, teammate, bird and opponents are all in
constant motion. Good spatial localization enables the players to move at the minimum distance
and time to reach the bird and return to ready position again for the next shot.
VISION SCREENING/TESTING PROCEDURES INDICATED FOR BADMINTON
ATHLETES: The choice of procedures is left to the discretion of the individual
practitioner.
Visual acuity: (static and dynamic)
1.
Normal Snellen - Distance and near
2.
Dynamic - AcuVision VTA
3.
Vectographic
4.
Autorefractor
5.
Record player with visual acuity disk at three speeds (33, 45, 75 rpm)
6.
Tachistoscopic acuity
Peripheral vision:
Humphrey Field Analyzer, Dicon, Goldmann, etc.
Depth perception:
1.
AO vectographic slide
2.
Stereo Circles - projected at distance
3.
Stereo Fly – near
4.
Randot - near Both speed of stereopsis and accuracy should be measured.
Eye motility:
1.
Versions and saccades
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2.
3.
Eye Trac: quantifies graphs on paper; good for before/after studies;
coaches can see if progress has been made.
Ober II
athletes and
Eye-hand/body/foot coordination:
1.
AcuVision 1000
2.
Wayne Saccadic Fixator: Normal use with the hands Footboard use which brings in the
badminton player's balance
Visualization:
1.
Verbal questions
2.
Getman Visual Manipulation Test
The following examples use the principles of visualization to enhance the badminton player's
serve. The player should:
1.
Analyze the opponent's standing position and try to serve toward the spot that will give
him the best advantage.
2.
Visualize his performance by imagining the motion of the shuttle. Visualization is the
ability of the player to use his mind's eye to track the shuttle as it leaves his palm,
contacts the racket, sails over the net and lands. Use the mind to determine the actions
and the strength required to direct and hit the shuttle over the net and land at the
predetermined position.
3.
Center of focus of the mind on the smallest detail of the opponent's court which the
service is going. Do not stare at the position for a long time but make a brief localization
of the position then concentrate to develop a solid awareness of the position relative to
the opponent.
4.
Execute the serve and watch the shuttle throughout the serve. Relax and follow through
with the serve.
5.
Playback the whole execution of the actions mentally, after the game. This is not as
helpful during the match because players need to prepare for the returns from the
opponent. But it is extremely helpful in practice sessions. Recall the direction of the
hand that held the racket and feel the strength of the delivery over the net. Repeat the
thought process several times to get the feeling for that particular serve. Finally, practice
the executions of the same serve enough times that the actions for that particular serve
become subconscious and automatic for future visual memory recalls.
Speed of recognition time:
1.
Tachistoscope
Speed of focusing:
1.
Wayne's near/far fixation module
2.
Flippers (near) +/- 2.00D
3.
Flippers (distance) P/O/-2.00D
4.
Near - Far Hart Chart Focus
Glare recovery speed:
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1.
2.
Night-Sight Meter
Nicolet Contrast Sensitivity Instrument
Eye fatigue tolerance without decreased performance:
1.
Ask the player or coach of the player whether the player is a consistent performer
throughout the match.
2.
Do a complete evaluation of all pertinent visual skills before and immediately after a
match or hard workout.
Fixation ability:
1.
Eye Trac
2.
Dicon perimeter which beeps when the subject loses fixation.
Central/peripheral awareness:
1.
AcuVision 1000
2.
Wayne Peripheral Awareness Trainer
3.
Dicon or other types of visual field analyzer
Spatial localization:
1.
AcuVision 1000
2.
Phorias: base-in and base-out
3.
Brock String
VISION TRAINING TECHNIQUES INDICATED FOR BADMINTON PLAYERS
1.
Visual acuity:
a.
The athlete should be fit with contact lenses for best visual acuity if an Rx is
needed. Soft contact lenses are usually the lens of choice for this sport, but rigid
lenses are used frequently when soft contacts are ruled out.
2.
Peripheral vision:
a.
Awareness of peripheral vision can be enhanced (see central/peripheral awareness).
b.
If a visual field defect is present, the player can learn to compensate by orienting
his/her game toward negating the weak point.
3.
Stereopsis:
a.
Stereopsis is the ultimate result of good binocularity. Train binocularity (BI and
BO) and stereo should improve with enhanced visual functions. Stereopsis,
especially the awareness of SILO and exact spatial localization is crucial. It is
important to train both at distance and near.
b.
Red/Green Anaglyphs and vectographic targets from Bernell can help build ranges
and stereopsis. An overhead projector can be used to project at distance.
4.
Ocular motility:
a.
Pegboard Rotators
b.
Wayne Rotator
8
c.
d.
e.
Computerized Anaglyphic Trainer
AcuVision 1000
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 player's balance system in response to the visual
signals he is getting off the board.
b.
AcuVision 1000
1) Excellent for peripheral localization, eye-hand coordination and
central/peripheral interaction.
c.
Stobe light:
1) The athlete has to concentrate more due to the increased visual noise.
2) Visual decisions must be made with less visual information.
6.
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
7.
Speed of focusing:
a.
Minus Lenses
b.
Near-Far Hart Chart
c.
Red/Green anaglyphic accommodative rock
d.
Wayne Saccadic Fixator
e.
Flippers
8.
Fixation ability:
a.
Counsel the player to fine focus (center) on the smallest possible detail he can see
on his target.
b.
The shorter the amount of time he fine-focuses on his target, the more intense his
focusing ability will be.
9.
Central/peripheral awareness:
a.
AcuVision 1000 is excellent for training central peripheral awareness and centralperipheral interaction.
b.
Wayne "stick-ups" are good for training.
c.
Concentrate on the amount of detail the athlete can gather from the periphery
without actually looking at the details directly.
d.
This skill cannot be developed overnight. The athletes must practice it daily until
they are good at it.
10.
Spatial localization:
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a.
b.
Train with the same instruments and equipment you use to measure and test this
skill.
Instruments:
1) Brock String (in all 9 positions of gaze)
2) Computerized Anaglyphic Trainer
SPORTS VISION PROBLEMS/SOLUTIONS RELATED TO BADMINTON
Safety risks: The shuttle hitting the player's eye from opponent's or partner's shot is the most
common injury. The partner's racket or elbow in the player's eye are the other serious ocular
injuries in badminton.
Possible solutions: Although the chance for eye injury for this sport is not likely;
protective goggles could be used to prevent any serious eye-related injuries.
Vision correction: Blurry vision in playing badminton can cause decrease in performance and
increase risk of injury in doubles.
Possible solutions: Contact lenses are ideally suited for the sport of badminton. A pair
of goggles with prescription is also highly recommended for protection against ocular
traumas.
High velocity projectiles: A badminton shuttle can travel at high speeds from a player's shot and
considering the short distance between players, the velocity and small size of the shuttle can
produce significant eye injury.
Possible solutions: Protective goggles usually solve the problem of ocular injuries.
Fogging of glasses: In the fast action of badminton, sweat and heat on the back of the lens cause
fog and can be very distracting for the players. Therefore decreased performance may result.
Possible solutions: Use of contact lenses for playing the sport or anti-fogging compound
applied to the lens can be useful.
Playing with only one usable eye: Some visual skills will be reduced in a monocular or
amblyopic player. However, the chance of losing the other eye in badminton is not very high.
Possible solutions: Protective goggles must be recommended to the monocular player to
protect the functional eye. Some visual enhancement can also be used to improve
player's safety and performance.
Presbyopia: This will affect ones reaction and response time due to the loss in speed of focusing
between distance and near. However, the overall body response and reaction time is slow for
other reasons as well.
10
Possible solutions: It is best to play the sport with someone who is evenly matched with
you in age and physical abilities to reduce the chance of injury. Best distance correction
is needed in order to play the sport. Bifocals are contraindicated since the image jumps
while attempting to fixate from distance to near.
Does an undetected vision problem exist? Just because a good badminton player does not
complain about eye strain or diplopia does not guarantee that their eyes and visual system are
100% efficient. Usually some type of enhancement can be implemented to improve a players
performance level.
Possible solutions: A complete sports vision analysis prior to participation in badminton
and every two years is recommended to rule out visual problems. Visual enhancement
training should also be considered to improve visual skills.
PROTECTIVE/CORRECTIVE EYEWEAR FOR BADMINTON PARTICIPANTS
1.
2.
3.
4.
5.
6.
Goggles, must be comfortable and fit the face of the player.
Sport straps for glasses.
Soft contact lenses are usually the preferred choice for sports correction for refractive
errors.
Gas permeable lenses can be used for the sport. Usually they are the secondary choice to
soft contact lenses.
Good quality yellow tinted lens to improve contrast in indoor matches.
Good quality absorbent head sweatband to keep sweat away from eyewear.
MOST COMMON OCULAR INJURIES SUSTAINED IN BADMINTON
1.
2.
3.
4.
5.
6.
7.
8.
9.
Corneal abrasion.
Trauma to the globe from the bird, a doubles partner's racket or elbow or body parts with
subsequent secondary complications.
Lacerations around the orbit, lids, or globe itself.
Ecchymosis of orbit.
Hyphema.
Traumatic iritis.
Subconjunctival hemorrhage.
Retinal detachment.
Traumatic cataract.
EMERGENCY FIRST-AID FOR OCULAR INJURIES SUSTAINED IN BADMINTON
Trainers should learn how to perform the following procedures:
1.
Lavage and rinse out ocular foreign bodies.
2.
Removal of contact lenses from injured player's eyes.
3.
Instillation of ophthalmic drops and ointments.
11
4.
Application of proper ocular lubricants or ophthalmic ointments to an injured eye prior to
application of a pressure bandage or fox shield.
For any direct serious trauma to the eye, it is important to state here that a visit to an optometrist
or ophthalmologist is an absolute necessity. It is difficult without a slit lamp biomicroscope to
totally assess the extent of the damage. Therefore, the victims eye should be covered with a
metal eye shield taped to the forehead and cheek. Get the victim immediate professional
attention. Do not allow the victim any delay in receiving this attention, regardless of how minor
the injury may appear to be at first. If the eye is perforated, non-sterile water or saline solution
could lead to serious secondary infection entering inside the eye. Any touching or probing of the
injured eye by an unskilled person applying first aid may elicit further damage.
OCULAR SUPPLIES FOR THE BADMINTON TRAINER'S FIRST-AID KIT
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Sterile Blinx 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)
Four or five Unisol or Barnes Hind unit dose twist-off-top tubes
Some butterfly tape strips to hold lacerated skin areas together
Small mirror
Blue ice
REFERENCES
1.
Badminton, James Poole, Goodyear Publishing Co., 15115 Sunset Blvd., Pacific
Palisades, CA, 1969.
2.
Sports Illustrated Badminton, J. Frank Devlin with Rex Lardner and editors of Sports
Illustrated, J.B. Lippincott Co., Philadelphia and New York, 1973.
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