114010

8/10/2019 114010

http://slidepdf.com/reader/full/114010 1/30

Power andPower and

the Tennisthe TennisServe Serve ..

ITF CoachesEducation Programme

Coaching High Performance Players Course

By Machar Reid & Miguel Crespo

8/10/2019 114010


A Powerful ServeA Powerful Serve – – A Key Ingredient ofA Key Ingredient of

Successful Tennis Performance Successful Tennis Performance

8/10/2019 114010


PreparationPreparationOBSERVE OBSERVE

Relaxation of facial muscles Relaxation throughout the bRelaxation of facial muscles Relaxation throughout the body.ody.

As tossing action begins weight more on the back foot.As tossing action begins weight more on the back foot.

Front toe pointed to the side or angled to the baseline**.Front toe pointed to the side or angled to the baseline**.

**Turning of the toe (normally pivoted about the heel of the foo**Turning of the toe (normally pivoted about the heel of the foot)t)

Reduce stress on the front kneeReduce stress on the front kneeAdequate rotationAdequate rotation

8/10/2019 114010


Ball Toss Ball Toss

““Straight forward and upStraight forward and up””

KrajicekKrajicek,, RusedskiRusedski

““Rotary styleRotary style””

SamprasSampras,, AgassiAgassi

Toss position in front and marginally to the left of the front f Toss position in front and marginally to the left of the front f oot at impact.oot at impact.

•• Effective development of racket Effective development of racket - - speed near impact.speed near impact.

•• Individual player preference and type of serve will alter this l Individual player preference and type of serve will alter this l ocationocation

between marginally to the left, to marginally to the right of th between marginally to the left, to marginally to the right of th e fronte front

foot.foot.

(Chow, 1999; Elliott, 2002)(Chow, 1999; Elliott, 2002)

8/10/2019 114010


Full Full backswing backswing ( ( Henman Henman ) )

vs.vs.

•• Individual characteristicIndividual characteristic

•• FullFull backswingbackswing may provide better rhythm andmay provide better rhythm and

reduced load on the shoulderreduced load on the shoulder

Abbreviated take Abbreviated take - - back (Rafter) back (Rafter)

8/10/2019 114010


FOOT UP vs. FOOT BACKFOOT UP vs. FOOT BACK -- A matter of styleA matter of style

FootFoot--up greater vertical force higher impact positionup greater vertical force higher impact position better upbetter up--andand--out trajectoryout trajectory

FootFoot--back larger horizontal forceback larger horizontal force more rapid movement to the net.more rapid movement to the net.

Height off ground atHeight off ground at

impact (cm)impact (cm)Impact position relativeImpact position relative

to standing heightto standing heightDistance into courtDistance into court

with 1st step (cm)with 1st step (cm)

FootFoot--backback

techniquetechnique

FootFoot--upup

techniquetechnique

3.460.0

46.0 7.2 1.54

1.48

(Elliott et al, 1986)

8/10/2019 114010


Backswing Backswing

COACHES CAN OBSERVE:COACHES CAN OBSERVE:

•• Full extension of tossing arm with shoulders tilted.Full extension of tossing arm with shoulders tilted.

•• Drive of lead hip forward.Drive of lead hip forward.

•• Elbow position such that upper arm is aligned with theElbow position such that upper arm is aligned with the

shouldersshoulders

8/10/2019 114010


8/10/2019 114010


Philippoussis Philippoussis vv Ivanisevic Ivanisevic

8/10/2019 114010


Philippoussis Philippoussis v Hsieh v Hsieh

8/10/2019 114010


Leg Drive Leg Drive

Effective leg drive and trunk rotationsEffective leg drive and trunk rotations

Distance between racket and bodyDistance between racket and body

•• Muscles on stretchMuscles on stretch

•• Long acceleration path for racketLong acceleration path for racket

(Elliott et al, 1999; Bahamonde, 1997)

8/10/2019 114010


((BahamondeBahamonde, 1997), 1997)

Internal RotatorsInternal Rotators

Stop Stop

External Rotation External Rotation

JOINT POWERJOINT POWER

Near max.Near max.Ext. Rot.Ext. Rot.

Ext. Rot. toExt. Rot. toimpactimpact

Upper ArmUpper ArmIntInt (+) /Ext ((+) /Ext (--))

Hand Flex (+)Hand Flex (+)

/ Ext ( / Ext (--))

11541154

214214

--44

--220220

8/10/2019 114010


COACHES CAN OBSERVE:COACHES CAN OBSERVE:

••Body is driven off the ground for impactBody is driven off the ground for impact

••The racket isThe racket is ‘‘drivendriven’’ away from, and behind the back away from, and behind the back

TRAINING TIP:TRAINING TIP:

High shoulder and elbow joint loadsHigh shoulder and elbow joint loads

The need to train muscles about the shoulder girdleThe need to train muscles about the shoulder girdle((latissimus dorsilatissimus dorsi,, pectoralispectoralis major andmajor and subscapularissubscapularis).).

(World Class Tennis Technique, 2001)(World Class Tennis Technique, 2001)

8/10/2019 114010


Swing to Impact Swing to Impact The key to an effective serveThe key to an effective serve

Sequence of coordinated movementsSequence of coordinated movements

RHYTHMRHYTHM

RACKETRACKET--SPEEDSPEED

IMPACT HEIGHTIMPACT HEIGHT

RACKET TRAJECTORYRACKET TRAJECTORY

2 KEY DIFFEREENCES between elite and2 KEY DIFFEREENCES between elite andlesser level players:lesser level players:

•• Speed of rotation of the hitting armSpeed of rotation of the hitting arm

•• Impact heightImpact height

(Bartlett et al, 1995)(Bartlett et al, 1995)

8/10/2019 114010


Optimal Racket SpeedOptimal Racket Speed(Kinetic or Kinematic Chain)(Kinetic or Kinematic Chain)

Segment RotationSegment Rotation

Leg Drive and Trunk RotationLeg Drive and Trunk Rotation

++

Upper arm Horizontal MovementUpper arm Horizontal Movement

Forward and AwayForward and Away

++

ForearmForearm PronationPronation

++

Forearm ExtensionForearm Extension

++

Upper arm internal rotationUpper arm internal rotation

++

Hand flexionHand flexion

++

Hand flexion (side)Hand flexion (side)

Joint MovedJoint Moved

ShoulderShoulder

ElbowElbow

Contribution to RacketContribution to Racket

Speed at ImpactSpeed at Impact

10%10% -- 20%20%

5%5% -- 10%10%

≈≈≈≈≈≈≈≈ 40%40%

WristWrist

Wrist/RacketWrist/Racket

RacketRacket

RacketRacket

WristWrist

≈≈≈≈≈≈≈≈ 30%30%

≈≈≈≈≈≈≈≈ --10%10%

15%15% -- 25%25%

NegligibleNegligible

(Elliott et al, 1995;(Elliott et al, 1995; LegananiLeganani, 1997; Van, 1997; Van GheluweGheluwe et al, 1997)et al, 1997)

8/10/2019 114010


Trunk rotationTrunk rotationto impact to impact

TRUNK ROTATION IN 3 PLANES OF MOTIONTRUNK ROTATION IN 3 PLANES OF MOTION

TRANSVERSETRANSVERSE FRONTALFRONTAL SAGITTALSAGITTAL

(Bahamonde, 2000)

About long axis of bodyAbout long axis of body ShoulderShoulder--overover--shouldershoulder Forward rotation (Somersault)Forward rotation (Somersault)

(Cartwheel)(Cartwheel)

Minor role, helps drive racketMinor role, helps drive racket Produces momentum for andProduces momentum for and Allows player to produce momentumAllows player to produce momentum

backwardsbackwards prepares body for impactprepares body for impact that is shifted from trunk racket armthat is shifted from trunk racket arm

8/10/2019 114010


(Bahamonde, 2000)

Trunk/Shoulder rotation related to impact location Trunk/Shoulder rotation related to impact location

Total Body Angular MomentumTotal Body Angular Momentum

NOTE:

• Large Forward Rotation• Contribution of shoulder-over-shoulder ****

** Differentiated FAST v SLOW Servers** Differentiated FAST v SLOW Servers

• Minimal Twist

RACKET AT LOWEST POSITIONRACKET AT LOWEST POSITION MAX EXTERNAL ROTMAX EXTERNAL ROT

TO MAX EXT ROTTO MAX EXT ROT TO IMPACTTO IMPACT

ForwardForward 2828 3030

ShSh overover ShSh 44 0.50.5

TwistTwist 00 --1.51.5

8/10/2019 114010


Shoulder Shoulder - - Over Over - - Shoulder Rotation Shoulder Rotation

8/10/2019 114010


Philippoussis Philippoussis vv Sampras Sampras

8/10/2019 114010


APPRECIATING THE IMPORTANCE OFAPPRECIATING THE IMPORTANCE OF

INTERNAL ROTATION INTERNAL ROTATION

8/10/2019 114010


WRIST ACTION FOLLOWINGWRIST ACTION FOLLOWING

INTERNAL ROTATION INTERNAL ROTATION

8/10/2019 114010


(Matsuo et al., 2000)

ThrowingThrowing

Shoulder Angle and PerformanceProfessional Japanese Pitchers

Optimal Shoulder Angle forOptimal Shoulder Angle for

Maximal Ball Velocity + MinimalMaximal Ball Velocity + MinimalStressStress ≈≈≈≈≈≈≈≈100 100 ºº

8/10/2019 114010


≈≈≈≈160οοοο≈≈≈≈ 100οοοο

Impact Alignment of Upper LimbImpact Alignment of Upper Limb--TrunkTrunk

INCORRECT INCORRECT CORRECT CORRECT

8/10/2019 114010


(Chow et al, 1999)(Chow et al, 1999)

The Serve: Impact Ball LocationsThe Serve: Impact Ball Locations – – First Serve First Serve

(4 Females; 5 Males: Atlanta Olympics(4 Females; 5 Males: Atlanta Olympics –– CentreCentre and Wide Serves (m))and Wide Serves (m))

FemalesFemales MalesMales

11stst 22ndnd 11stst 22ndnd

InIn--FrontFront 0.8/0.80.8/0.8 0.50.5 0.8/0.80.8/0.8 0.60.6

VerticalVertical 2.6/2.62.6/2.6 2.72.7 2.8/2.72.8/2.7 2.72.7

SideSide--toto--sideside --0.2/ 0.2/ --0.20.2 --0.10.1 --0.2/ 0.2/ --0.20.2 --0.60.6

Ball traveled FORWARD and LEFTBall traveled FORWARD and LEFT

Related to LEFT TOERelated to LEFT TOE

8/10/2019 114010


The importance of an up The importance of an up - - and and - -

out hitting action out hitting action

Elite players impact the ball after itElite players impact the ball after it

has begun to drop (2.5 has begun to drop (2.5 - - 20.0 cm).20.0 cm).

HeightHeight 108 km/h108 km/h 145 km/h145 km/h 180 km/h180 km/h

2.03m2.03m 1.91.9ºº 0.60.6ºº 0.00.0ºº

2.54m2.54m 2.62.6ºº 1.41.4ºº 0.80.8ºº

3.05m3.05m 3.53.5ºº 2.12.1ºº 1.61.6ºº

Forward Rotation (topspin)Forward Rotation (topspin)

(Brody, 1987)

8/10/2019 114010


The weight of a serve! The weight of a serve!

Rusedski vs Sampras Rusedski vs Sampras

Similar serve speedSimilar serve speed ≈ ≈≈ ≈ ≈ ≈≈ ≈ 117/118 mph 117/118 mph

Same initial spin ratesSame initial spin rates ≈ ≈≈ ≈ ≈ ≈≈ ≈ 2500 rpm 2500 rpm

Different initial angle of rotation Different initial angle of rotation

(Yandell et al., 2002)

8/10/2019 114010


Ball flight (cm) Ball flight (cm)

SamprasSampras higher topspin componenthigher topspin component

At returnAt return –– SamprasSampras serve 500 rpm more & 10serve 500 rpm more & 10--30cm higher30cm higher

(Yandell et al., 2002)

117.5117.5 ––

132.5132.5

125125 -- 145145

HeightHeight

Range atRange at

Ret/BLRet/BL

12512517.517.512.512.5 –– 22.522.5282.5282.5RUSEDSKIRUSEDSKI

13513517.517.512.512.5 –– 27.527.5282.5282.5SAMPRASSAMPRAS

AverageAverage

Height atHeight at

Ret/BLRet/BL

AverageAverage

NetNet

ClearanceClearance

Range ofRange of

NetNet

ClearanceClearance

AverageAverage

ContactContact

HeightHeight

PLAYERPLAYER

8/10/2019 114010


1st1st 2nd2nd

MM FF MM FF

ForwardForward 3434 2828 3232 2525

UpUp 1717 1313 19*19* 1313

SideSide--toto--sideside --33 00 22 77

ResultantResultant 3939 3131 3838 2929

PostPost--impactimpact 2727 22 (22 (≈≈≈≈≈≈≈≈ 70%)70%) 2727 2121

(Brody, 1987)

First v Second ServeFirst v Second Serve

(4M & 4F Professionals) (4M & 4F Professionals)

Racket Velocities (m/s) Racket Velocities (m/s)

8/10/2019 114010


Left foot landingLeft foot landing

•• Leg drive, shoulderLeg drive, shoulder--overover--shoulder and forward trunk action +shoulder and forward trunk action +

impact locationimpact location•• 95 % of professionals land on front foot95 % of professionals land on front foot

““Kick Kick --back back ”” reaction forcereaction force

Minimize stressMinimize stress

““Kick outKick out”” (Williams example)(Williams example)

FollowFollow

through through

(World Class Tennis Technique, 2001)

Initial continued internal rotation of the upper arm and forearmInitial continued internal rotation of the upper arm and forearm pronationpronation..

8/10/2019 114010


Thank youThank you

Any questions?Any questions?

Documents

114010