🎾 Medicine And Science In Tennis¶
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Medicine And Science In Tennis — tài liệu 40 trang từ thư viện sách tennis.
Chủ đề chính: Huấn luyện, Recovery, Strategy
Tóm tắt nội dung (trích từ tài liệu gốc): June 2008 � volume 13 � number 2 medicine and science in tennis � Rolling for recovery � Meet the expert: Dr. Gary Windler � Tennis training � PRO UTM Player Orientation � Best serving strategy www.stms.nl www.stms.nl Journal of STMS in co-operation with: ITF � ATP � Sony Ericsson WTA Tour ISSN: 1567-2352 Message from the President Medicine and Science in Tennis is a Journal produced by the Society Dear Members, for Tennis Medicine and Science (STMS) in co-operation with the ITF, the ATP, and the Sony Ericsson WTA Tour, and is issued three Babette Pluim, the founding and current editor of the
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June 2008 � volume 13 � number 2
medicine and
science in tennis
� Rolling for recovery
� Meet the expert: Dr. Gary Windler
� Tennis training
� PRO UTM Player Orientation
� Best serving strategy
www.stms.nl www.stms.nl
Journal of STMS in co-operation with: ITF � ATP � Sony Ericsson WTA Tour
ISSN: 1567-2352 Message from the President
Medicine and Science in Tennis is a Journal produced by the Society Dear Members,
for Tennis Medicine and Science (STMS) in co-operation with the
ITF, the ATP, and the Sony Ericsson WTA Tour, and is issued three Babette Pluim, the founding and current editor of the STMS journal,
times a year (February, June, and October). Medicine and Science in has decided to step down after 13 years in office so this will be the
Tennis is listed in Altis, Free Medical Journals, MedNets, last STMS journal she is editing. Once again, this issue demon-
NewJour, Sponet and SIRC Sports Discus. strates the very high standard our journal has reached as a result
of her tireless efforts and we owe her a very big "Thank You"!
The International Board of the STMS:
President: Marc R. Safran, San Francisco, CA, USA This edition has several original articles in all disciplines of
E-mail: president@stms.nl tennis medicine and science. There are articles on the adoles-
Vice-President: Javier Maquirriain, Buenos Aires, Argentina cent athlete, mental health and psychology, and optimisation
E-mail: vicepresident@stms.nl of performance through the use of statistics. There are medicine
Secretary/Treasurer: Bill Durney, San Francisco, USA papers on imaging of os acromiale and the prevention of ankle
E-mail: info@stms.nl sprains, both important topics as the first is a bit of a controversial,
Membership Officer: Todd S. Ellenbecker, Scottsdale, AZ, USA but significant issue, and the other due to the great frequency of ankle
E-mail: membership@stms.nl sprains in tennis. There are tips for coaches, and information about
Past-Presidents: Babette M. Pluim, Ede, the Netherlands what the professional players are learning, in the WTA article on the
Per A.F.H. Renstr�m, Stockholm, Sweden Players' Pro University about professional life and life after tennis.
W. Ben Kibler, Lexington, KY, USA
Additional Members: Peter Jokl, New Haven, CT, USA Continuing in the series of Meet the Expert, we have included an interview with Gary
Bernard Montalvan, Paris, France Windler, a member of the ATP Medical Team, clinician and active researcher of issues
Associates to the Board: Miguel Crespo, Representative of the ITF relating to the professional tennis player. Further, there are book and DVD reviews about
Kathy Martin, Representative of the Sony Ericsson WTA Tour tennis medicine and science to help our readership evaluate what they may want to use to
Gary Windler, Representative of the ATP further investigate areas of tennis medicine and science.
Honorary Members: Irving V. Glick, Great Neck, NY, USA
Savio L-Y Woo, Pittsburgh, PA, USA Lastly, a conference calendar of upcoming tennis related meetings (in addition to review
of the most recent tennis science and technology meeting) is provided, including the
North American Regional Committee: two upcoming STMS meetings. There is the North American Regional Meeting being
Chairman: Marc R. Safran, San Francisco, CA, USA held August 1-2, 2008 in Cincinnati during the ATP tournament and hosted by Neeru
Neeru Jayanthi, Chicago, IL, USA Jayanthi and Robert Rhoades. Additionally, the World Congress of the STMS will be held
Peter Jokl, New Haven, CT, USA in Tokyo, Japan during October 2-4, 2008, hosted by Moroe Beppu. The world congress
W. Ben Kibler, Lexington, KY, USA promises to be a fantastic meeting, with three concurrent sessions, including work shops for
Carol Otis, Portland, OR, USA trainers, debate sessions, current concepts and some of the newest, exciting original research
E. Paul Roetert, Key Biscayne, FL, USA in tennis medicine.
Savio L-Y Woo, Pittsburgh, PA, USA
Once again, many thanks to Babette for all her hard work over the last 13 years. The
European Regional Committee: STMS Journal is a magnificent legacy of her ongoing efforts to improve the delivery of
Chairman: Giovanni di Giacomo, Rome, Italy sports medicine education to our tennis community.
Gilles Daubinet, Paris, France
Hans-Gerd Pieper, Essen, Germany I hope to see you in Cincinnati and Tokyo!
Babette Pluim, Ede, the Netherlands
Angel Ruiz-Cotorro, Barcelona, Spain Sincerely,
Michael Turner, London, United Kingdom
Marc R. Safran, MD
South American Regional Committee: President STMS
Chairman: Rogerio Teixeira Silva, S�o Paulo, Brazil
Javier Maquirriain, Buenos Aires, Argentina
Scientific Committee:
Chairman: J. Chandler, Jacksonville, AL, USA
Bruce Elliott, Perth, Australia
W. Ben Kibler, Lexington, KY, USA
Karl Weber, Cologne, Germany
Savio L-Y Woo, Pittsburgh, PA, USA
Educational Committee:
Chairman: Neeru Jayanthi, Chicago, IL, USA
Peter Jokl, New Haven, CT, USA
W. Ben Kibler, Lexington, KY, USA
Kathy Martin, Melbourne, Australia
Piotr Unierzyski, Poznan, Poland
Gary Windler, Summerville, SC, USA
Editorial Board:
Editor-in-Chief: Babette M. Pluim, Ede, the Netherlands
E-mail: editor@stms.nl
Todd S. Ellenbecker, Scottsdale, AZ, USA
Neeru Jayanthi, Chicago, IL, USA
Javier Maquirriain, Buenos Aires, Argentina
Maarten Moen, Amsterdam, the Netherlands
Rogerio Teixeira Silva, S�o Paulo, Brazil
Bert J.G. van Weelde, The Hague, Netherlands
Gary Windler, Summerville, SC, USA
Editorial Assistant:
Anne Meredith, Wakefield, United Kingdom
Subscriptions and Membership:
Todd S. Ellenbecker
Physiotherapy Associates
Scottsdale Sports Clinic
Scottsdale, AZ 85258, USA
E-mail: membership@stms.nl
Annual Subscription fees due 1st January 2008
Full membership: $175.00
Student membership $100.00
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Cover photo:
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Disclaimer:
This journal is published by the Society of Tennis Medicine and
Science for general information only. Publication of information in
the journal does not constitute a representation or warranty that
the information has been approved or tested by the STMS or that
it is suitable for general or particular use. Readers should not relay
on any information in the journal and competent advice should be
obtained about its suitability for any particular application.
� 2008 Society of Tennis Medicine and Science.
All rights reserved. No part of this publication may be reproduced
in any form without prior written permission of the copyright.
holder. Opinions and research expressed in this journal are not
necessarily those of the STMS.
STMS is sponsored by:
2
Contents medicine and
science in tennis
2 Message from the President Marc R. Safran
4 Rolling for recovery Allistair McCaw
8 Physiological and behavioural responses to thermal stresses in tennis Sarah Morante
10 Introduction to PRO UTM Player Orientation Thomas Livengood, Ashley Keber and Kathy Martin
13 Tennis Training Enhancing on-court performance Mark Kovacs, Britt Chandler and Jeff Chandler
14 Imaging of sports-related muscle and tendon injuries in children and adolescents
Evert J.L. Vandervliet, Filip M. Vanhoenacker, Annemiek Snoecks, Jan L. Gielen, Pieter van Dyck, and Paul M. Parizel
16 ITF hosts successful TST Congress
17 Conference calendar 2008
18 Preventing ankle sprains and improving balance in tennis players
Vasiliki J. Malliou, Paraskevi Malliou, Asimenia Gioftsidou, Stavros Douvis and Alexandros Mavvidis
21 The Knee: Patient evaluation / Imaging / Therapy and Rehabilitation
Rudolph Schabus and Elisabeth Bosina
22 Loading and velocity generation in the high performance tennis serve Machar Reid
24 Applying match statistics to increase serving performance
Tristan Barnett, Denny Meyer and Graham Pollard
28 Australian elite tennis juniors' perceptions of the importance of mental skills
Janet A. Young
32 Meet the expert: Dr Gary Windler
34 What is the best serving strategy? Geoff Pollard
39 Core Stability Training on DVD Carl Petersen and Nina Nittinger
40 10th STMS World Congress
3
Coaches Corner
Allistair McCaw
Med Sci tennis 2008;13(2):4-7
Rolling The best kept secret to maximising your perfor-
mance is simple: "Recover better" according to
for tennis performance trainer Allistair McCaw. In this
recovery article Alistair explains his views on the potential
benefits of using a simple piece of foam to optimise
recovery and recommends eight specific foam-
rolling exercises for players of all standards.
How fast your body recovers from the previous match or training Having a programme that incorporates good post training/match
session can ultimately determine your next performance, because recovery techniques is critical for a player's overall development
if your body has not been able to repair and regenerate sufficient- and performance. It enables the player to perform the next time
ly, you simply will not perform to your maximum potential. with less fatigue and in doing so, adapt to workloads faster.
I am a firm believer in the saying "Your next performance is
only as good as your recovery from the last". With this in mind, The most common techniques used by players today are sports
recovery and regeneration are treated with as much importance massage, aquatic therapy (pool running, movement exercises etc.),
in the programmes I set for my athletes as movement, nutrition yoga and stretching. These all definitely contribute to the healing
and mindset. process, but the problem is the time that lapses between the end
of the training session and when the massage, aquatic therapy
Tennis is a physically demanding sport. Players can experience or yoga happens. So what would be the best way to bridge this
muscle restriction (feeling stiff ), which can alter joint motion important gap between training and taking care of the recovery?
and lead to poor movement patterns, a faster rate of fatigue and One suggestion is to have your athletes rolling on a foam roller
injury. the minute they finish their workout.
As a sports performance trainer working in tennis, I have Why foam rolling?
discovered that the primary focus of many coaches and players Hard exercise may lead to increased tension of our muscles and
is on training and competing, whilst recovery is often forgotten joints. Self-massage exercises (self-myofascial release) on this
or given less attention. I often see athletes who put time and tre- simple piece of foam can immediately reduce soft-tissue tension
mendous effort into their workouts, only to quickly rush through and speed up the recovery process. Using a foam roller can also
their cool down and stretching routines. They are missing one of provide similar benefits as a deep-tissue massage. By increasing
the most important aspects of their pre-habilitation (preparing flexibility and decreasing muscle tension, it can help to prevent
the body against injury) post performance body maintenance. injury, decrease muscle pain and improve function and perfor-
mance. Your muscle resembles a rubber band and the further you
Recovery is stretch it, the further it will launch when you let it go. If you can
increase the elasticity in the muscle by improving your flexibility,
probably one of the result will be increased power and improved performance.
the most overlooked I believe that the foam roller is one of the most effective,
all-around self-maintenance tools you will find, as it not only
aspects in an releases chronic muscular tension and pain (caused by playing or
performing movement), but can actually restructure your skeletal
athletes' program system so that it aligns more positively with gravity. It is simple to
use as you use your own body weight to roll on the round foam
roll, massaging away restrictions to normal soft-tissue extensibil-
ity. Foam rolling is like getting a massage without the expense
of a massage therapist. In fact it's like having your own physical
therapist, chiropractor, and masseuse at your beck and call. How-
ever, I definitely do not condone the services these practitioners
offer as a good massage is always recommended.
4
There are many potential benefits of foam rolling - it The better your
� can prevent joint stiffness and possibly reduce injury risk recovery the faster
� increases flexibility and joint function your progress will be
� speeds up the recovery process
� is portable, light (weighs less than 500grams) and easy to travel
with
� limits the costs of a regular massage
Your turn! Place your body on the roller and slowly roll up and down (for
I have put eight exercises together specifically for tennis players. about 30-45 seconds) along the muscle group you are targeting.
These exercises cover all the major muscle groups involved in the I have a basic rule: If it hurts, it needs more attention. So if you
game. Make these exercises part of your regular cool-down routine. find a particularly tight area, pause on that spot. Putting pressure
Perform them directly after your training session or match (after on a tight area can help release the tissue.
a cool-down jog or spin on bike, but before stretching) to maxi-
mize their recovery time!
Exercise 1.
Iliotibial band
Position yourself side lying on
foam roll. Bottom leg is raised
slightly off floor. Maintain head
in `neutral', with ears aligned with
shoulders. Roll just below hip joint
down the lateral thigh to the knee.
Exercise 2.
Gluteal muscles
Begin in position as shown with
foot crossed to opposite knee. Roll
on the posterior hip area. Increase
the stretch by pulling the knee
toward the opposite shoulder.
5
Exercise 3.
Hamstrings
Place hamstring on the roll with
hips unsupported. Opposite leg
is bent to support this position.
Roll from knee towards posterior
hip while keeping quadriceps
tightened.
Exercise 4.
Quadriceps
Body is positioned prone with
quadriceps on foam roll. It is very
important to maintain proper core
control (abdominal drawn-in posi-
tion and tight gluteal muscles) to
prevent low back compensations.
Roll from pelvic bone to knee,
emphasizing the lateral thigh.
Exercise 5.
Calves
Place calf on the roll with hips
supported. Have other knee bent
to support a balanced position.
Roll from below knee to Achilles
tendon.
Exercise 6.
Adductors
Extend the thigh and place foam
roll in the groin region with body
prone on the floor. Be cautious
when rolling near the adductor
complex origins at the pelvis.
6
Exercise 7. About the author
Latissimus dorsi
Position yourself side lying with
arm outstretched and foam roll
placed in axillary area. Thumb
is pointed up to pre-stretch the
latissimus dorsi muscle. Movement
during this technique is minimal.
Exercise 8.
Upper back
Cross arms to the opposite shoul-
der to clear the shoulder blades
across the thoracic wall. While
maintaining abdominal drawn-in
position, raise hips until unsup-
ported. Also stabilize the head in
`neutral'. Roll mid-back area on the
foam.
Summary
Whatever your level, foam rolling should be an integral part of
your daily routine. It will aid injury prevention and recovery, and
is one of the easiest and cheapest ways to improve recovery, allevi-
ate aches and pains and improve flexibility. Use the roller directly
after your workout prior to your cool-down stretch and remem-
ber that areas that hurt need more attention. A quicker recovery
translates to a better performance the next time you play!
Tennis performance specialist Allistair McCaw is founder of Performance Tennis
which specializes in tennis-specific conditioning training. Allistair has worked
with no less than 6 top 20 tennis players including Jelena Dokic, Nathalie Dechy,
Michaella Krajicek and Dinara Safina. He has also trained the world numbers one
and two squash players Nicol David (world champion) and Natalie Grinham.
Address for correspondence www.performancetennis.com
7
PhD thesis
Sarah Morante
Med Sci Tennis 2008:13(2):8-9
Physiological and
behavioural responses to
thermal stresses in tennis
Background: Tennis is played year-round throughout the world Whilst environmental conditions within the prescriptive zone
in a wide variety of weather conditions. Often players in the enable the maintenance of body core temperature, skin tempera-
Australian Open, held in the middle of summer, are faced with ture is hypothesized to rise with increasing ambient temperature
air temperatures exceeding 40�C. The current Extreme Heat up to approximately 36�C in order to maintain convective heat
Policy used at the Australian Open postpones play at an absolute dissipation. Since the thermal gradient for convective heat loss
air temperature 35�C and a Wet Bulb Globe Temperature is reduced as air temperature approaches skin temperature, with
28�C. This is based on the American College of Sports Medi- heat being gained when skin temperature exceeds air tempera-
cine's Exertional Heat Illness Policy for distance running. There- ture, the evaporation of sweat becomes the major if not sole
fore, this policy may be inappropriate for tennis where activity is method of heat dissipation. Therefore, sweat rate would be ex-
interspersed with rest periods which reduce the overall exercise pected to increase with ambient temperature in order to maintain
intensity. Furthermore, there has been no known scientific thermal equilibrium. Whilst core body temperature is main-
evaluation of this policy. However, a review of its applicability to tained within tolerable levels during the prescriptive zone, players
tennis using the current information base is difficult since there may subjectively rate conditions within the prescriptive zone as
is no objective information about the effects of environmental intolerable due to thermal discomfort that results from high core
conditions on players' physiological responses, comfort and and skin temperatures and/or skin wettedness. In more stressful
behaviour. Tennis players of all levels would benefit from objec- environmental conditions, or when players are experiencing
tive and comprehensive information relating to how the thermal physiological or subjective strain, players are expected to modify
environment affects their health and safety, and comfort. Such their behaviour to reduce the workload and heat production. This
information enables them to make decisions about whether they would be indicated by a reduction in effective playing time, point
choose to play tennis on a given day, the duration and intensity duration and stroke frequency. Within the prescriptive zone, it
at which they play, the required fluid replacement, strategies to is anticipated that thermoregulatory responses will agree with
manage thermal comfort (e.g. wetting the skin, moving to the previously published studies including: metabolic heat produc-
shade or fanning), and tactical modifications. These decisions tion of approximately 680 W, heart rate of around 145 beats.
enable players to minimise the risk of developing heat illness, and min-1; body core (rectal) temperature of around 38.2�C; and
maximise comfort in adverse weather conditions. sweat rate of approximately 0.93 L.h-1. When conditions exceed
the prescriptive zone, core body temperature is expected to be
Research objectives: The aim of this thesis was to obtain com- higher in response to the greater heat load that results in thermal
prehensive data on environmental and metabolic heat stress, and equilibrium being achieved at a higher core body temperature.
body temperature regulation during competitive singles tennis However, it is unknown whether the thermal environment and
matches over each of the seasons in Sydney, Australia. These data exercise intensity will represent a stress level above the upper
were then be used to determine whether a steady-state core body threshold of the prescriptive zone during the experimental tennis
temperature and thermal comfort are being achieved in tennis, matches within this study.
in addition to the mechanisms responsible for their attainment
(i.e. autonomic / physiological thermoregulation or behavioural / Methods: In the laboratory, the maximum aerobic power
psychological thermoregulation?). These data were also used for (VO2max) and body composition for each subject was assessed.
the rational analysis of heat stress, which will enable prediction Experimental tennis matches were completed by men and
of all thermal exchanges and thus, tolerable environmental condi- women of varying standards in a range of thermal environments.
tions for tennis. Finally, these data enabled an evaluation of the Each of the six thermal stresses (air temperature, humidity, solar
current Extreme Heat Policy and the suggestion of an alternative radiation, air movement, clothing and metabolic heat produc-
method for assessing heat stress in tennis (the Belding and Hatch tion) were measured or predicted for each tennis match and
Heat Stress Index). player. A whirling psychrometer was used to measure dry bulb
(air) temperature and wet bulb temperature (for humidity) at 20
Hypotheses: There is expected to be a range of environmental minute intervals throughout each tennis match and player. Mean
conditions (the prescriptive zone) in which thermoregulation radiant temperature (for solar radiation) was assessed by a globe
is successful and body core temperature is maintained relative thermometer, which recorded globe temperature each minute
to the workload but independent of the environmental stress. throughout matches. Air movement was also logged each minute
8
throughout matches by a mechanical anemometer. An additional � 95.4 W.m-2, respectively. The required evaporation for thermal
observation, natural wet bulb temperature, was measured at 20 equilibrium (Ereq) for the observations averaged 415.0 � 104.5
minute intervals for the calculation of Wet Bulb Globe Tem- W.m-2 and was associated with the observed sweat rate (P <
perature (WBGT). The thermal properties of clothing were 0.0001). However, the relationship between the predicted Ereq
predicted for normal tennis attire. Metabolic heat production was and the observed sweat rate was weaker than expected (R2 =
predicted from a known regression equation developed for the 0.33). Air temperature and relative humidity were modelled to
association between relative workload (% VO2max) and rectal predict conditions where Ereq exceeded the maximum evapora-
temperature. The regression equation determined for oxygen tive capacity of the environment (Emax), resulting in body heat
uptake (VO2) and heart rate in the laboratory for each subject storage.
was also used to predict metabolic heat production. The thermal
strains measured during tennis included rectal temperature, Conclusions: Core body temperature remained controlled in
skin temperature, sweat rate, heart rate and subjective responses. environmental conditions at and a little beyond the two heat
Rectal temperature and four skin temperatures (arm, chest, thigh stress indices comprising the current Extreme Heat Policy. This
and leg) for each player were recorded every minute throughout suggests the current policy does not exceed the upper limit of the
matches by custom-built temperature loggers. Each player's heart prescriptive zone and thereby endanger players. Both autonomic
rate was recorded at 15 seconds intervals throughout play using a / physiological thermoregulation (increase in skin temperature
heart rate monitor. Body water loss for sweat rate was deter- and sweat rate) and behavioural / psychological thermoregula-
mined by weighing subjects fully clothed and equipped before tion (reduction in point duration and effective playing time) were
play, after 30 minutes of play and at the completion of the match. involved in the control of core body temperature. The rational
Body mass changes would also include evaporative water loss analysis of heat stress provides a more comprehensive approach
from the respiratory tract and metabolic fuel used during activity. to setting environmental limits. However, the prediction of ther-
However, these changes are considered negligible and do not mal exchanges using standard equations was less accurate than
detract from the validity and reliability of this method of sweat expected, meaning these equations will need to be modified for
loss assessment. Drink bottles were weighed at the same times improved prediction in tennis.
to account for fluid intake. During the change of ends after every
six games, players indicated subjective responses of perceived About the author
exertion, thermal comfort, sweatiness and a rating of conditions
(thermal sensation). Notational analysis was conducted through-
out matches to assess activity patterns and workload.
Results: Air temperature ranged from 14.5 to 38.4�C, rela- Sarah Morante has completed a Bachelors degree and a PhD (April 4th, 2008) in
tive humidity ranged from 21.8 to 73.7% and WBGT ranged the School of Exercise and Sport Science at The University of Sydney. She cur-
between 13.5 and 29.2�C. Mean point duration was 5.8 � 1.3 rently operates a sport and fitness consultancy company that ranges from providing
s and effective playing time (the proportion of the match spent lecturing services to higher education providers including Sydney University and
in play) averaged 23.7 � 5.2 %. This equates to a work to rest sporting/fitness organizations.
ratio of approximately 1 : 3.5. Positive associations were found
for the change in rectal temperature with both point duration (P
< 0.001) and effective playing time (P < 0.05). Heart rate was
also positively correlated with point duration (P < 0.0001) and
effective playing time (P < 0.05). Rectal temperature averaged
38.5 � 0.4�C (62% VO2max) and mean heart rate was 136.8
� 13.6 beats.min-1 (66 % VO2max). Both rectal temperature
and heart rate were unaffected by the two components of the
current Extreme Heat Policy (air temperature and Wet Bulb
Globe Temperature), even in conditions exceeding the thresholds
for each index (35�C and 28�C, respectively). Skin temperature
demonstrated a positive association with air temperature (P <
0.0001). Sweat rate averaged 13.32 � 5.56 mL.kg.h-1 or 0.92
� 0.42 L.h-1, and demonstrated positive relationships with air
temperature (P < 0.0001), skin temperature (P < 0.0001) and
rectal temperature (P < 0.03). Thermal comfort declined with
increasing rectal temperature (P < 0.03) and skin temperature (P
< 0.0001). Both point duration (P < 0.002) and effective playing
time (P < 0.0002) were reduced as conditions were rated increas-
ingly difficult. Oxygen uptake (VO2) during tennis was 2.5 �
0.5 L.min-1 when predicted from rectal temperature and 2.6 �
0.5 L.min-1 when predicted from heart rate, which corresponds
to metabolic heat production of 459.5 � 76.3 W.m-2 and 483.9
9
Sony Ericsson WTA Tour
Thomas Livengood, Ashley Keber and Kathy Martin
Med Sci Tennis 2008;13(2):10-12
Introduction PRO UTM is the Sony Ericsson WTA Tour's umbrella
to PRO UTM institution for education. The PRO UTM staff is
Player responsible for educating players and their sup-
Orientation port teams from the onset of their professional
careers and covers development in three core
domains:
� Human Development
� Tennis Development
� Business Development
When women tennis players graduate to this elite professional These were performance based, like injuries, length of season,
level from the ITF circuits and/or juniors competitions, they competition and expectations; all stressors typically seen in pro-
become more than mere competitors on the Sony Ericsson fessional sports. The reported stressors from 1994 (e.g., media,
WTA Tour: they are a part of the Sony Ericsson WTA Tour parents and family) were no longer at the top of the list. These
(the Tour). In order to take charge of their careers, players are changes in the main stressors, combined with the impressive
responsible to make wise and informed decisions. PRO UTM helps statistical results: 24 % increase in career longevity (significance
players gain the knowledge and skills they need to make these p<0.2), decrease in burnout from a rate of 7% to less than 1%
professional decisions. It aims to guide players to minimize the (significance p=0.01), demonstrate that the PRO UTM programs
stressors associated with women's professional tennis and to in place between 1994 and 2004 did positively impact the career
promote their safety, career longevity and performance. longevity, health and well-being of players on the women's tour.1
Consequently, the panel strongly recommended that these effec-
Rookie Phase eligibility tive PRO UTM programs be made available to more athletes and
PRO UTM is divided into three phases to ensure that as players' at a younger age. With this aim, from 2008, the Rookie Phase of
rankings and needs increase, so does the level of training and PRO UTM programs will be available to players online.
skill-building. The Rookie Phase is the introductory phase of
PRO UTM and houses the Player Orientation, the focus of this Introduction to the Player Orientation
article. The Rookie Phase begins when a player eighteen (18) The Player Orientation helps players learn the on-site reali-
years of age or younger participates: ties and responsibilities of a professional Tour player. The key
objectives of the Player Orientation are to optimize performance,
� I n two (2) or more WTA Tour main draw singles events in a enhance player health, and improve each player's ability to make
52 week period, or effective business decisions, ones that are beneficial to the individ-
ual and the Tour at-large.
� In a Grand Slam singles (main draw or qualifying). The on-line modules are divided into three or more interactive
lessons, to ensure the information is comprehensively covered
History of PRO UTM in manageable doses. The on-line Player Orientation course
PRO UTM programs came about as a result of the 1994 Age Eli- includes audio, video, picture images and text. At the end of each
gibility Commission (now the PRO UTM Advisory Panel) report, lesson, players must pass an on-line quiz and evaluate the lesson
which identified the major stressors in women's professional content. Players must successfully complete each on-line course
tennis and made complementary recommendations. The 1994 within 90 days of eligibility. The first modules to be launched in
Age Eligibility Commission report findings strongly indicated 2008 include:
the need for developing skills and train these young athletes to
succeed in the professional environment. Accordingly, the Player Copyright WTA Tour Inc.
Orientation was expanded from a four-hour group session over-
view of the Tour to the system now in place. The current model is The PRO UTM program's have had a positive effect on the health and well-being of the players
a comprehensive, skill-development process, divided into multiple
phases, each of which is based on the needs of the player and
business requirements of her particular career stage.
In 2004, the Sony Ericsson WTA Tour invested in a 10-Year-
Review to determine the effectiveness of the PRO UTM programs,
including the Age Eligibility Rule.1 This review is considered to
be the most comprehensive study of age-related programs in the
history of professional sports and included a literature review and
an analysis of quantitative, qualitative and statistical data.
The 2004 review indicated that new stressors had emerged.
10
Players learn how the media grows the sport (Copyright WTA Tour Inc) � On-site Operations � players are educated about the Tour
supervisors' responsibilities, what it requires to run a successful
An Intro to the Pro's event and consider the needs of the tournaments and players,
o History of the WTA, structure of the Sony Ericsson WTA and the enforcement of Tour rules (e.g., Patch Policy, Code of
Conduct, Medical Time-Out).2 Practical skills include: the
Tour, why PRO UTM exists, how the Tour and ITF/other tennis process of the draw and the daily schedule of play, and proper
governing bodies work together, practical guidance on entry/ entry and withdrawal procedures.
withdrawal procedures, how the rankings work and the Age
Eligibility Rule.2 � P layer Relations � players are introduced to membership and
benefits for members, the pension program, the importance of
Athlete Safety & Security player meetings and the role of Player Council and the gover-
o S afety at home, safety during travel, safety at tournaments; nance of the Tour and player news and information. Practical
activities include: attendance at a player meeting and meeting
Tour initiatives to promote safety (e.g., code of conduct for with a Player Council representative.
player support team members, athlete assistance programs and
services) and the Tour's cumulative responsibility to promote a � Communications � players learn how the media works as a
safe and healthy environment. business and how media grows the sport and helps to connect
players with the fans, and influences the image of individual
Rookie Hours players, tournaments and the Tour. Practical skills include:
o A n in-depth, interactive lesson reviewing individual Tour review of advice from former players, attendance at a press
conference and a review of interview techniques.
departments. Players learn: the purpose and role of each de-
partment; critical rules specific to that department; credentials, � Marketing & Sponsorship � players learn about the sponsor-
qualifications and licensure of staff members in departments; ship agreements of the Sony Ericsson WTA Tour, players' roles
and practical skills related to the topic in each lesson. The goal with sponsors and the important relationship between players
is that players will develop the relevant professional skills neces- and the community, charities and fans. Practical activities in-
sary to succeed in the Tour environment. clude: important advice on self-promotion and marketing, meet
the sponsors and participate in sponsor activities.
The following departments are covered in the Rookie Hours:
� S port Sciences & Medicine � players are introduced to the � Athlete Assistance � aims to enhance players' health, well-
being and safety. Players learn about the services, resources and
training (treatment) room; the physical therapy and massage preventative strategies available to help manage the environ-
therapy personnel; how and where to access health services on- mental and life stressors, improve overall coping skills and
and off-site; Tour rules pertaining to health (example: Extreme enhance performance. Practical activities include: an on-line
Heat Condition Rule);2 biomechanical services, nutrition tour of the Achieve Solutions website,3 the Athlete Assistance >>
and hydration services; and injury prevention practices, like
the annual physical. Practical skills include: blister treatment
and prevention, contents of a first aid kit, and proper dynamic
warm-up and recovery techniques.
11
Copyright WTA Tour Inc.
Players meet the sponsors during the Rookie Hours (Copyright WTA Tour Inc)
and Physically Speaking topics, and an introduction of Athlete
Assistance personnel to a player's support team.
Thomas Livengood graduated with a Bachelors of Arts in Sociology and Russian � Tournament Operations � players are introduced to the be-
Language and Literature from Kent State University. Tom joined the Sony Erics- hind the scenes functions of tournaments and how players and
son WTA Tour's PRO UTM Department as Coordinator, in October 2003. Tom's tournaments work together for maximum effect. They learn the
primary responsibilities as Coordinator, PRO UTM include development, tracking responsibilities of tournament staff and volunteers, the details
and maintenance of the Orientation program and monitoring the progress of of tournament marketing, finance and administration, and the
players through the requirements of the Rookie Phase. His duties include working importance of the tournament profiting to help grow the sport,
with players and their support teams (coaches, parents, agents) to help them learn and player prize money. Practical activities include: a visit to the
about the professional tennis environment. He also assists with other Sony Erics- volunteer tent or ticket booth, a sponsor walk-through and a
son WTA Tour educational initiatives such as the Coach Symposium and Junior private tour of the facility.
forums.
Before joining the Tour, Tom' s past professional experiences include cross-cultural Transition from the ITF to the Sony Ericsson WTA Tour
orientation and curriculum development and teaching international high school At the junior level, the International Tennis Federation has
exchange students. He also lived in Russia for more than three years in the 1990's, developed the ITF Junior Tennis School with a goal to help the
and is fluent in conversational Russian. junior tennis community develop as humans and tennis players.
This enterprise complements Tour initiatives and uses a blend of
Ashley Keber graduated with a Bachelors of Arts in English from the University on-line education and on-site forums, which introduce players
of Florida, Phi Beta Kappa. She has worked with the Tour since 1997, where she to topics including sport sciences, health, safety, media training
has been the PRO UTM department head, overseeing such programs as the Age and anti-doping. PRO UTM personnel participate in One Game
Eligibility Rule, Player Orientation, media training and mentor program. She initiatives, such as the Wimbledon Junior Forum, which is a
has served on the Women's Sports Foundation Career Development task force, collaborative seminar led by the ITF with the Sony Ericsson
the Athlete Development steering committee and has been a featured speaker at WTA Tour and the ATP. Past and present members of the PRO
coaching conferences and an invitee to the annual Board meeting and symposium UTM Advisory Panel are also actively involved in the ITF Junior
for National Center for Human Performance. Prior to joining the Sony Ericsson Tennis School.4
WTA Tour, Ashley was a broadcast liaison for the 1996 Atlanta Olympic Broad-
casting group, networks which included Eurosport, BBC, ZDF, Australia 7 and Conclusion
NBC. While attending university, she was an instructor and residence counsellor The purpose of the Player Orientation is to educate players about
for the UF-Nike Summer Tennis program. their responsibilities on the Tour and gain an understanding of
what it means to be a professional. The interactive on-line course
explains and brings to life the building blocks of the business.
The player learns that she has of a vested interest to ensure the
success of each tournament and the Tour to the same extent that
she is responsible for her own personal success.
The Tour is committed to and offers professional development
programming that is dynamic, effective and relevant to players' lives
and careers. The Panel continues to meet annually to provide guid-
ance on all PRO UTM programming initiatives. The PRO UTM team
strives to create, innovate and execute the best training possible for
players, so they can maximize their opportunities and fulfil their
responsibilities as role models and ambassadors of the sport.
Kathy Martin graduated from the Lincoln Institute of Health Sciences with
a Bachelor in Applied Sciences (Physiotherapy) in 1984. She was awarded the References
Australian Physiotherapy Association Sports Physiotherapist title in 1999. She
received her Bachelor Arts (1991) and Graduate Diploma in Adolescent Health 1. Otis CL, Crespo M, Flygare CT, Johnston PR, Keber A, Lloyd-Kulkin D, Loehr
& Welfare (2004) from Melbourne University. She is currently completing her J, Martin K, Pluim BM, Quinn A, Roetert EP, Stroia KA and Terry P. The Sony
Masters in Counselling at Monash University. Kathy was the Australian Olympic Ericsson WTA tour ten-year age eligibility and professional development review.
Team Physiotherapist in 2000, the Australian Fed Cup Team Physiotherapist from Br J Sports Med 2006;40:464-8.
1994 to 2000, and Sports Medicine Consultant to Tennis Australia from 1998 to 2. Sony Ericsson WTA Tour. 2007 Sony Ericsson WTA tour official rulebook.
2003. Prior to working in tennis, she ran her own physiotherapy clinic and was the WTA Tour Inc, 2007.
physiotherapist to the Australian Ballet Company and School and the Victorian
College of the Arts. She joined the Sony Ericsson WTA Tour as a Primary Health 3. Value options. Achieve solutions. [homepage on the Internet]. � 1999-2007.
Care Provider in 1991. She is currently the Director, Athlete Assistance, Sony Available from: https://www.achievesolutions.net
Ericsson WTA Tour.
4. McFetridge H. Back to school. ITF World: The International Tennis Federation's
Address for correspondence: flagship magazine. 2007;32:26-9.
Kathy Martin, Sony Ericsson WTA Tour, One Progress Plaza, Suite 1500, St.
12 Petersburg, FL 33701, USA. E-mail: KMartin@wtatour.com
Book review About the authors
Mark Kovacs, W. Britt Chandler and T. Jeff Chandler
Med Sci Tennis 2008;13(2):13
Tennis Training
Enhancing on-court performance
they can better understand the technical explanations of the coaches,
doctors and athletes.
As I am a physical trainer for the regional tennis squad and the Dutch
National Paralympic Squad preparing for the Paralympic Games in
Beijing, this book is definitely of interest for me. Additionally, it is also
useful for medical specialists, tennis coaches, athletes and parents.
Marijn Zaal
Physical trainer Royal Netherlands Lawn Tennis Association
This book has been written by three tennis experts who combine years of academic
knowledge with real-world practical coaching to truly blend the art and science
of tennis performance.
Tennis training: Dr. Mark Kovacs obtained a top 100 ITF junior ranking, won a US"gold-ball,"
enhancing on-court and competed in many international tournaments including the US and Australian
Open before attending Auburn University where he was an All-American and
Pages: 245 NCAA doubles champion. He has combined researched scientific evidence in
Price: 19.95 US$ his coaching profession both as a high-level tennis coach as well as a strength and
conditioning specialist (CSCS) training hundreds of high school, collegiate, and
ISBN-13: professional athletes. In February of 2008, Dr. Kovacs was named the Manager of
978-0-9722759-7-2 United States Tennis Association Sport Science in Boca Raton, Florida.
At first sight"Tennis training" by Mark Kovacs, Britt Chandler and W. Britt Chandler has a master's degree in exercise science from Auburn University
Jeff Chandler could be just one of the many books about tennis and played collegiate tennis. He is certified as both a strength and conditioning spe-
training. However, after studying it in more detail, it turns out to be a cialist (CSCS) and certified personal trainer (NSCA-CPT). He also is a certified
`must-have' book for tennis medical and performance specialists. tennis coach through the USPTA. He currently works as both a tennis coach and
Tennis is an individual and a technical sport. Because of the physi- strength conditioning specialist with some of the top juniors in the country. Britt is
ological and technical aspects of tennis, we must train the body also the editorial assistant for the Strength and Conditioning Journal and has con-
in many areas. A player has to develop 4 sides: the player has to tributed book chapters and presentations on tennis specific research and training.
specifically develop technical, tactical, mental and physical strengths.
Within the physical training there are also many aspects that need to Dr. T. Jeff Chandler has over 20 years experience as a tennis researcher and sports
be developed. The authors have succeeded with the book"tennis train- science consultant, advisor, and author for many tennis organizations including the
ing" to write a manageable and synoptic book for players and coaches. USTA, USPTA, ITF, STMS and PTR. He has over 100 scientific publications,
The book focuses on physical training in the sport of tennis. In book chapters, and presentations relating to tennis training and performance. He
general it does not give any new information. It contains summaries is currently Department Head of Health, Physical Education & Recreation at
of existing literature and references to known facts. However, what Jacksonville State University, Jacksonville, Alabama, and is the Editor in Chief of
makes this book so good is the information about training principles, the Strength and Conditioning Journal published through the National Strength
training laws, periodisation and experiences from the practices, and Conditioning Association. Dr. Chandler is certified with distinction as both a
focused on tennis. Supported by science, clearly described and filled CSCS*D, and NSCA-CPT* D. He is a Fellow in the American College of Sports
with pictures the book is filled with tennis-specific exercises. Medicine (FACSM) and a Fellow in the National Strength and Conditioning
"Tennis training" makes physical training in tennis easy to under- Association (FNSCA).
stand and to use by coaches, parents and athletes. For coaches it is a
perfect reference book after their education/training to tennis coach.
In practice, it is a book that can easily be used particularly because of
the large number of specific exercises. Athletes gain in detail insight
in what happens with their body during training, what exercises are
really important and why physical training is such an important part
of their development. Parents can also benefit from this information.
They are usually further removed from the practice and this way
13
Abstract
Evert J.L. Vandervliet, Filip M. Vanhoenacker, Annemiek Snoecks, Jan L. Gielen, Pieter van Dyck, and Paul M. Parizel
Med Sci Tennis 2008;13(2):14-15
Imaging of Sports-related muscle injuries are frequent in
sports-related adults and youngsters. The presentation of muscle
and tendon trauma largely depends on the patient's
muscle and age: in youngsters the skeleton is weaker than in
tendon injuries adults, whereas their ligaments and tendons can
in children and withstand more force.1 Therefore, skeletal lesions,
more specifically those of the physis, are common
adolescents in children.1 The type of sports activity determines
the nature of the lesion. Most commonly apophy-
ses of the hip and pelvis are subject to avulsion
fractures in youngsters, and in tennis the pelvis is
the most likely site to be affected.2 Lesions can be
either acute or chronic.
Acute apophysiolysis (or apophyseal avulsion fracture) usually Figure 1. Avulsion
occurs between puberty and the age of 25, and is caused by violent of the iliac crest in a
muscle contraction.1 Sudden pain is reported, and examination 17-year-old tennis
may reveal loss of function, local swelling and tenderness.1 Differ- player.
ent sports may cause acute strain on different apophyses, causing 1a. Coronal CT at the
lesions on specific locations (Table 1). The most common sites are level of the iliac crest.
the ischial tuberosity (most frequently seen in gymnastics), ante- Note the separation of
rior inferior spine (common in soccer and tennis) and the anterior the left iliac crest from
superior iliac spine. The iliac crest is the site most often affected in the underlying iliac bone
tennis, but other apophyses may be involved as well (Figure 1a.).2 (arrow).
Initially conventional radiography with contralateral comparison
(in order to differentiate a true lesion from the unfused physis) 1b. Axial T2-weighted
usually suffices, showing a displaced fragment at the origin or MR image demonstrates
insertion of the muscle or tendon.1,3 However, plain radiographs the presence of a high
may be misinterpreted as negative in children, when an apophyseal signal intensity cleft
avulsion fracture is not displaced or when the apophysis is not between the avulsed apo-
ossified. In such cases, ultrasound, CT and MRI (Figure 1b) may physis and the iliac bone
prove helpful.4 During healing the callus on plain radiography (arrow). Note also high
is excessive with hypertrophy of the surrounding cortex, which signal intensity edema
may simulate an osteosarcoma or exostosis.4 MRI initially shows within the adjacent
haematoma and periosteal stripping, although fragments without abdominal wall muscles
marrow are often missed. (asterisk).
Table 1. M ost frequent sites of avulsion fractures, their corresponding muscle insertion and the most frequent athletic activities
responsible for these lesions
Location (decreasing order of frequency) Muscle insertion Most frequent sports activities
ischial tuberosity hamstrings gymnastics, soccer, fencing, tennis, running
anterior inferior iliac spine rectus femoris soccer, athletics, tennis
anterior superior iliac spine sartorius soccer, athletics, gymnastics
superior corner of pubic symphysis rectus abdominis soccer, fencing
iliac crest abdominal muscles soccer, gymnastics, tennis
lesser trochanter iliopsoas athletics
14
Figure 2. Old apophyseal Evert Vandervliet, MD is resident radiology at the University Hospital Antwerp, About the authors
avulsion fracture at the UZA and the AZ St. Maarten in Duffel-Mechelen, Belgium.
inferior anterior iliac
spine in a 15-year-old
male tennis player.
Axial CT demonstrates an irregularly delineated bony mass at the insertion
of the left rectus femoris muscle at the AIIS, due to unremodelled callus for-
mation. In the absence of history of previous sports trauma, this may mimic
a malignant bone tumor.
Subacute and chronic avulsion fractures or insertional overuse Filip Vanhoenacker, MD, PhD is radiologist at the University Hospital Antwerp,
lesions typically involve the proximal attachments of the gracilis UZA and the AZ St. Maarten in Duffel-Mechelen, Belgium and guest lecturer at
(gracilis-adductor syndrome) and adductor muscles (chronic the University of Antwerp.
proximal adductor insertion avulsion syndrome) or distal adduc-
tor brevis muscle attachments (chronic distal adductor insertion Annemiek Snoeckx, MD, is senior resident at the University Hospital Antwerp,
avulsion syndrome or thigh splints).5 UZA.
Radiographic findings of the proximal gracilis-adductor
syndrome consist of a mixture of bone rarefaction and reactive
sclerosis that mimic normal variants, osteomyelitis or neoplasms
(Figure 2).5 Periosteal bone apposition at the medial proximal
third of the femur can be seen in thigh splints. Scintigraphy
shows an elevated tracer uptake whereas MRI initially demon-
strates bone marrow and soft tissue edema in all cases, and fatty
replacement and sclerosis in the later stages of proximal gracilis
and adductor injuries.3,5 Thus MRI may demonstrate a variable
signal according to the reparative stage of the lesion (either due to
edema, fatty reconversion or sclerosis).5
Musculotendinous injuries are treated conservatively, although
in acute avulsion fractures surgery may be necessary if displace-
ments exceed 2 cm, or when malunited or hypertrophic frag-
ments cause prolonged complaints.4
Conclusions Jan Gielen, MD, PhD, is co-chair at the Department of Radiology and section
1. In the adolescent, the physis is particularly susceptible to head of Musculoskeletal Radiology, UZA and assistent professor of Radiology at
the University of Antwerp.
trauma.
2. The nature of the sport determines the pattern of injury.
Lesions due to tennis usually involve the inferior and superior
anterior iliac spine, the ischial tuberosity and the iliac crest, but
other apophyses may be affected as well. Both the radiologist
and the sports physician should be aware of these lesions.
3. During the healing phase the excessive callus formation of
acute /avulsion lesions may simulate an osteosarcoma or
exostosis.
4. The differential diagnosis of chronic overuse injuries in the
immature skeleton includes normal variants, osteomyelitis and
tumoral lesions.
Pieter Van Dyck, MD, is staff member Musculoskeletal Radiology, UZA.
References
1. Rossi F, Dragoni S. Acute avulsion fractures of the pelvis in adolescent competi- Paul Parizel, MD, PhD, is chairman of the Department of Radiology, UZA and
tive athletes: prevalence, location and sports distribution of 203 cases collected. full professor of Radiology at the University of Antwerp.
Skeletal Radiol 2001;30:127-31.
Address for correspondence: F.M.Vanhoenacker, Dept of Radiology, University
2. Vanhoenacker FM, Snoeckx A, Gielen JL, Van Dyck P, Parizel PM. Imaging of Hospital Antwerp, UZA, University of Antwerp, Wilrijkstraat 10, B-2650
muscle injuries in children and adolescents. Flemish J Sports Med Sports Sci Edegem, Belgium. Tel: +32 3 821 3532, Fax +32- 3 825 2026 e-mail: filip.
2005;101:39-41 vanhoenacker@telenet.be
3. Bencardino JT, Palmer WE. Imaging of hip disorders in athletes. Radiol Clin N
Am 2002;40:267-87.
4. Boutin RD, Russell CF, Steinbach LS. Imaging of sports-related muscle injuries.
Radiol Clin N Am 2002;40:333-62.
5. Vandevenne JE, Vanhoenacker F, De Beuckeleer L, De Schepper AM. Chronic
avulsive injury of the hip. JBR-BTR 2000;83:31.
15
Conference report
ITF hosts The ITF Science & Technical Department hosted
successful its 3rd International Congress on Tennis Science &
TST Congress Technology (TST) at Whitelands College at the Uni-
versity of Roehampton in London 10-12 September
2007. Over 90 of the world's leading tennis science
and technology researchers were present for three
days of outstanding presentation and discussion.
Tennis Science & Technology 3
S. Miller and J. Capel-Davies (eds)
London: International
Tennis Federation, 2007
Pages: 204
Price: 60 US$
ISBN: 1-903013-34-8
www.itftennis.com
16
Almost 50 presentations were given, the standard of which was Racketsports). Among the many topics discussed during the
extremely high. In addition to academics, the delegates included discussion were electronic line-calling, equipment development,
representatives from the equipment manufacturers, coaches, player physiology and coaching.
court constructors and national governing bodies. The congress
was officially opened by ITF Vice President Geoff Pollard who The quality of presentations was extremely high, and covered a
commented that the Congress was a gathering of "the brains of variety of topics, including equipment technology, player develop-
tennis", and how understanding technology was crucial to the ment and analysis, and the environment. The second Howard
future of the game. In addition, he contributed to four scientific Brody Award (sponsored by CISLunar Aerospace) for outstand-
papers which focused on the probability of a player winning a ing contributed paper, which was presented in person by Profes-
match based on improving their level of play at different stages of sor Brody, went to Simon Choppin of Sheffield University, Great
the match. Britain, for a paper on the three-dimensional analysis of racket and
ball during play. Professor Brody commented that the 3rd TST
Two keynote presentations were given: the first, by Dr Stuart Congress was thought-provoking, and generated more interaction
Miller, ITF Head of Science & Technical, and which opened between delegates than either of the two previous events.
the Congress, discussed the role of the Science & Technical
Department in the development of rules and regulations for Over 40 delegates took the opportunity to visit the ITF Techni-
tennis equipment. This presentation included an overview of cal Centre, which contains the world's leading tennis-specific
the projects undertaken by the ITF Technical Centre, and their research and testing laboratory. Prior to the congress dinner being
contribution to the understanding and protection of the nature held at the All England Lawn Tennis Club, delegates also had the
of tennis. The second was presented by Professor Steve Haake opportunity to tour the facility for a behind-the-scenes look at
of Sheffield Hallam University, Great Britain, who examined the Wimbledon.
evolution of the tennis racket and its effect on serve speed. The congress dinner was attended by ITF President Francesco
To encourage debate amongst the delegates, a discussion panel, Ricci Bitti, who stressed the importance of technology in tennis,
entitled `Rules are made to be broken: where does tennis go and the responsibility of the ITF to control the nature of the
from here?', addressed current issues with respect to the Rules of game through an understanding of equipment.
Tennis. As Chairman of the ITF Rules of Tennis Committee,
Geoff Pollard played a major part on the distinguished panel, and Proceedings, containing all the papers presented at the Congress,
was joined by Chris Bowers(journalist and broadcaster), Steven are available for purchase through the ITF Store
Martens (LTA Head of Technical Support), Angie Cunning- https://store.itftennis.com.
ham (Vice-President, Player Relations, Sony Ericsson WTA
Tour), and Ralph Schwenger (Head Sport AG, R&D Director
Conference calendar 2008
June 2008 October 2008
2nd World Congress on Sports Injury Prevention STMW World Congress
Oslo, 26-28 June Tokyo, 2-4 October
http://www.klokeavskade.no http://www.icstms2008.jp/
July 2008 British Association of Sports and Exercise Medicine
Annual Congress
American College of Sports Medicine;
International Team Physician Course Brighton, 8-10 October
http://www.basem.co.uk/
Santiago, 23-25 July
http://www.acsm.org November 2008
August 2008 International Federation of Sports Medicine;
FIMS World Congress
STMS North American Regional Conference
Barcalona, 18-23 November
Cincinnati, Ohio, USA http://www.femede.es/congressbarcelona08
1-2 August
http://www.stms.nl
17
Coaches corner
Vasiliki J. Malliou, Paraskevi Malliou, Asimenia Gioftsidou, Stavros Douvis and Alexandros Mavvidis
Med Sci Tennis 2008;13(2):18-20
Preventing ankle sprains
and improving balance in
tennis players
Introduction balance exercise programme includes a closed-chain lower limb
Tennis is a popular sport, with an increasing number of active position. The proposed pieces of equipment are a mini-trampo-
players.1-3 Although tennis is a non-contact sport, it is associated line, balance boards with air and wooden balance boards. The use
with a number of injuries.2-5 Most injuries in tennis occur in the of a mini-trampoline can change the weight bearing surface from
lower extremities,4-5 consisting primarily of muscle strains and hard to soft and provide an element of instability, thus requiring
ligaments sprains in the ankle and knee,2-6 followed by the upper more control in the weight-bearing lower extremity exercises for
extremities and trunk area.5 stability.23 With regard to the balance boards; the first is a bal-
Furthermore, tennis is a sport that requires speed, power, and ance board, 40 cm in diameter and filled with air flat side up and
functional strength movements for an extended period. There- down. The second board is a flat wooden disk, 51 cm in diameter,
fore, it is important to train the tennis player to maximise his and 1 cm high with a round hardwood block (9.5 cm diameter,
performance while incorporating specific exercises to elimi- 3.7 cm high) in the middle of its base. The board with the hemi-
nate injury risk factors.7 More specifically, specialists propose spherical bottom moves in all directions. With the use of these
strengthening exercise programmes to restore muscle imbalances, pieces of equipment, the balance exercise programme includes
stretching exercise programmes to decrease muscle stiffness and four different tennis drills (Table 1).
balance exercise programmes to improve proprioception.8-11
The term "proprioception" was described by Sherrington,12
as the awareness of body segment positions and orientations.
Recent evidence in other sports, suggests that balance exercise
programmes may improve proprioception and neuromuscular
control, and reduce the number of lower limb injuries.9,13-17
Proprioception is especially important for tennis players, because
tennis movement characteristics are complex, the footwork is
demanding and a high level of balance is required.18,19 Since bal-
ance is one of the fundamental qualities that tennis players must
develop20 tennis-specific balance exercises should be included in
a player's daily training routine in order to maximise performance
and minimise injury risk.9,21,22
The aim of the present paper was to present a structured
programme of how to incorporate specific balance exercises for
tennis players to improve balance and prevent lower limb injuries.
Specific characteristics of the balance exercise programme
According to the previous studies:
1. T he content of the balance exercise programme should be
incorporated into tennis training drills because all the exercises
are designed to be a natural part of playing movements; 15,17
2. The tennis-specific balance exercises should be done on a
tennis court or in a controlled environment (e.g. gym room)
and allow the joints to move in the same way as they would in
normal functional tennis activities;17,23
3. T he exercises may be progressed by changing from bilateral to
unilateral standing in the first drill only;
4. T he exercises performed on balance boards require a combina-
tion of balancing skills and certain tennis skills (e.g. dribbling,
ground strokes and volleys);
5. T he duration of each drill should be increased progressively.
The balance exercise programme
The combination of tennis drills and balance exercises make the
training session more sport-specific and interesting. The specific
Figure 1. Player (left-handed) stands on the wooden balance board
18 with the hemi-spherical bottom surface and tries to dribble the ball
with the racket.
Table 1. Recommendations for a tennis balance exercise programme
Drills preformed on: Training period Rest period between each drill
a.trampoline
b.balance board with air
c.wooden balance board
First drill: Standing while dribbling
(with the racket and tennis ball) 1st wk: 20s/drill (total 6mins) 20s (total 6mins)
Second drill: Ground strokes 2ndwk: 30s/drill (total 10mins) 15s (total 5mins)
Third drill: Ground stroke/volley 3rd and 4th wk: 40s/drill (total 12mins) 20s (total 6mins)
Fourth drill: Control and ground stroke 5th and 6th wk: 60s/drill (total 12mins) 20s (total 4mins)
(Each drill performed 2 times) 7th and 8th wk: 60s/drill (total 14mins 20s (total 4-5mins)
Mins, minutes; s, seconds; wk, week
Dribbling
In this drill the tennis player stands with both feet on the mini-
trampoline and dribbles the ball with the tennis racket (Figure 1).
Then, the player does the same drill on the balance board with air
and then, on the wooden balance board. The player the repeats all
these exercises with a one-legged stance.
Ground strokes
In this drill, the tennis player stands in a closed position (side-
ways) with both feet on the mini-trampoline. The coach feeds
the ball to the player who tries to hit a forehand drive and return
Figure 3. Player (left-handed)
stands on a mini trampoline and
tries to hit a forehand volley.
Figure 2. Player stands on balance
boards with air (one foot on each
board) and tries to return the ball with
a forehand drive.
the ball to the coach (Figure 2). The drill is then repeated on the
backhand side. As the programme progresses the player does
the same drill on two balance board with air (one foot on each
board) and then, on the wooden balance boards.
Ground stroke and volley
In this drill the tennis player stands sideways with both feet
on the mini trampoline and tries to control the ball which the
coach feeds before returning it with a forehand drive. The drill
is then repeated using a backhand drive to return the ball. As
the programme progresses the player does the same drill on two
balance boards with air (one foot on each board) and then, on the
wooden balance boards. >>
19
About the authors Paraskevi Malliou, Ph.D. is Associate Professor and athletic trainer at the Demo- Summary:
critus University of Thrace, Department of Physical Education and Sports Science In conclusion, we recommend tennis coaches to include balance
in Komotini, Greece. exercises in to their players' daily tennis training programmes
to improve proprioception and potentially reduce lower limb
injuries. These balance exercises should be combined with tennis
drills in order to be more sport-specific and interesting. The
programme is intended to enhance hand-eye coordination and
subconscious reaction. The duration of the recommended balance
exercise programme should be eight weeks with a daily training
duration that increases from 6 to 14 minutes (Table 1).
Vasiliki J. Malliou, Ph.D is a physical education and tennis instructor at the Nati- References
onal and Kapodistrian University of Athens, Department of Physical Education &
Sports Science, in Athens, Greece. 1. Perkins RH, Davis D. Musculoskeletal injuries in tennis. Phys Med Rehabil Clin
N Am 2006;17(3):609-31.
Asimenia Gioftsidou, Ph.D. is a physical education teacher and athletic trainer
at the Democritus University of Thrace, Department of Physical Education and 2. K�hne CA, Zettl RP, Nast-Kolb D. [Injuries- and frequency of complaints in com-
Sports Science, in Komotini, Greece petitive tennis- and leisure sports]. Sportverletz Sportschaden 2004;18(2):85-9.
Stavros Douvis, Ph.D. is Associate Professor and Head of the tennis course at the 3. Bylak J, Hutchinson MR. Common sports injuries in young tennis players.
University of Athens, Dept of Sports Science. Sports Med 1998;26(2):119-32.
Alexandros Mavvidis, Ph.D. is Associate Professor and Head of the tennis course 4. Feit EM, Berenter R. Lower extremity tennis injuries. Prevalence, etiology, and
at the University of Thrace, Dept. of Sports Science. mechanism. J Am Podiatr Med Assoc 1993;83(9):509-14.
Address for correspondence:
Vasiliki J. Malliou, Ph.D., Makrigianni 36, Ilioupolis, 16345, Athens, Greece 5. Pluim BM, Staal JB, Windler GE, Jayanthi N. Tennis injuries: occurrence, aetiol-
ogy, and prevention. Br J Sports Med 2006;40(5):415-23.
6. Silva RT, Takahashi R, Berra B, Cohen M, Matsumoto MH. Medical assistance
at the Brazilian juniors tennis circuit--a one-year prospective study. J Sci Med
Sport 2003;6(1):14-8.
7. Kovacs M. Is static stretching for tennis beneficial? A brief review. Med Sci
Tennis 2006;11(2):14-16.
8. Askling C, Karlsson J, Thorstensson A. Hamstring injury occurrence in elite soc-
cer players after preseason strength training with eccentric overload. Scand J Med
Sci Sports 2003;13(4):244-50.
9. Caraffa A, Cerulli G, Projetti M, Aisa G, Rizzo A. Prevention of anterior cruciate
ligament injuries in soccer. A prospective controlled study of proprioceptive train-
ing. Knee Surg Sports Traumatol Arthrosc 1996;4(1):19-21.
10. Fried T, Lloyd GJ. An overview of common soccer injuries. Management and
prevention. Sports Med 1992;14(4):269-75.
11. Rozzi SL, Lephart SM, Sterner R, Kuligowski L. Balance training for persons
with functionally unstable ankles. JOSPT 1999;29(8):478-486.
12. Sherrington GS. The integrative action of the nervous system: Review of the
afferent neural system of knee and its contribution to motor learning. New York,
Charles Scribner's Sons, 1906.
13. Hewett TE, Lindenfeld JV, Riccobene JV, Noyes FR. The effect of neuromus-
cular training of the incidence of knee injuries in females athletes. Am J Sports
Med 1999;27:699-706.
14. Hoffman M, Payne G. The effect of proprioceptive ankle disk training on
healthy subjects. JOSPT 1995;21(2):90-3.
15. Wedderkopp N, Kaltoft M, Lundgaard M, Rosendahl M, Froberg K. Preven-
tion of injuries in young female players in European team handball. A prospec-
tive intervention study. J Med Sci Sports 1999;9:41-7.
16. Malliou P, Gioftsidou A, Pafis G, Beneka A, Godolias G. Proprioceptive training
(balance exercises) reduces lower extremity injuries in young soccer players. J
Back Musculoskeletal Rehabil 2004;17:101-4.
17. Gioftsidou A, Malliou P. Preventing lower limb injuries in soccer players.
Strength Cond J 2006;28:2-5.
18. Lin CH, Lien YH, Wang SF, Tsauo JY. Hip and knee proprioception in elite,
amateur, and novice tennis players. Am J Phys Med Rehabil 2006;85(3):216-21.
19. Jerosch J, Thorwesten L, Teigelkotter T. Proprioception of the shoulder joint in
young tennis players. Sportverletz Sportschaden 1997;11(1):1-9.
20. Elstein R, Bowden MC. Tennis kinetics. New York: Simon and Schuster; 1985.
21. Bahr R, Lian O, Bahr IA. A twofold reduction in the incidence of acute ankle
sprains in volleyball after the introduction of an injury prevention program. A
prospective cohort study. Scand J Med Sci Sports 1997;7(3):172-177.
22. Verhagen E, van der Beek A, Twisk J, Bouter L, Bahr R, van Mechelen
W. The effect of a proprioceptive balance board training program for the
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2004;32(6):1385-93.
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delphia: W.B. Saunders Company, 1996.
20
Book review
Rudolph Schabus and Elisabeth Bosina
Med Sci Tennis 2008;13(2):21
The Knee:
Patient evaluation /
Imaging / Therapy and
Rehabilitation
Das Knie This book about the knee joint is a manual for About the authors
Diagnostik- physicians, physical therapists and patients. It is
Therapie- Rehabilitation written in a way patients can understand, but
Rudolph Schabus and Elisabeth Bosina
Vienna: Springer Verlag 2007, Pages: 164, Price: EUR 99,95 of sufficient medical interest to be useful to
ISBN: 978-3-211-29686-8 physicians such as orthopaedic surgeons
www.spinger.com and sports physicians. The book empha-
"The knee" is divided into three main sections. The first section sizes the interaction between the physi-
includes general information in which the anatomy of the knee cian, physical therapist and patient during the
is explained and biomechanical information is provided for the rehabilitation process. It explains how to make
different knee components during movement. The second section a successful return to sport and how to prevent
of the book describes common knee injuries in detail, and explains injuries from re-occurring.
trauma mechanism, physical examination and injury-specific imag-
ing. It also outlines conservative treatment and operative treatment University Professor Dr. Rudolf Schabus was born in Hermagor/K�rnten
techniques. To help the reader understand the recommended con- in1954 and studied medicine in Vienna (1973-1978). He went on to specialise in
servative treatment and specific rehabilitation phases, each chapter traumatology at the University Clinic for Traumatology, Vienna (1979-1985) and
is supplied with drawings of the suggested exercises. The operative received certification as a sports physician in 1990. He is currently the Head of the
techniques are clarified by images as well, to explain the different Dept. of Traumatology and Sports Injuries in the Wiener Privatklinik.
phases of the operation. Schabus and Bosina particularly focus on
the anterior cruciate ligament and gonarthrosis. They also discuss
other common problems such as posterior cruciate ligament
lesions, meniscal lesions, cartilage damage and patellar instability.
The third section of the book explains the various exercises, using
appropriate images, for stretching and strengthening the differ-
ent muscles around the knee joint. There is the added bonus of a
DVD showing all the exercises in the book which is provided with
each copy. In summary, this book provides an excellent overview
of the anatomy, injuries and rehabilitation techniques of the knee.
It would be particularly useful for patients and coaches, and health
care professionals starting a career in sports medicine.
Maarten Moen Elisabeth (Lisi) Bosina was born in Vienna in 1959 and, after qualifying as a
sports physician physiotherapist, she went on to specialise in sports physiotherapy. From 1989, she
worked in private practice in Vienna. Shortly after the completion of this book, in
2005, she was tragically killed in an avalanche accident.
21
PhD thesis
Machar Reid
Med Sci Tennis 2008;13(2):22-23
Loading and velocity generation in
The `why' The challenges along the way (establishing the methodology)
Shoulder injuries rank among the most prevalent and debilitat- In tennis, normative data describing the key mechanical char-
ing injuries sustained by professional tennis players. The loads acteristics of selected strokes is widespread, yet the number of
endured by the tissues of the shoulder during stroke produc- strokes upon which these data should be based has rarely been
tion, and more particularly the serve, are commonly implicated documented.7-8 Consequently, verification of the repeatability
in shoulder joint injury.1-3 Indeed, past evidence points to these of the tennis serve, and the minimum number of executions
loads increasing along with serve velocity, as well as with varied upon which representative observations could be made, needed
segment use.4 The aim of this thesis was to therefore quantify to be established. In some agreement with theoretical models of
how different types of serves (i.e. the flat serve and the kick serve) performance analysis,9 reliable evaluation of the serve appeared
and how different service techniques (i.e. the foot-up) affected to require at least three successful service trials. Determination
shoulder joint loading among high performance able-bodied and of appropriate methods of data treatment, including an apposite
wheelchair players. Exciting in that it represented an opportunity smoothing technique to best represent higher-order kinemat-
for three-dimensional (3D) stereophotogrammetry � the gold ics both pre- and post-impact, saw a cubic spline interpolative
standard in motion analysis � to evaluate a tennis stroke, and, procedure used.
challenging as the shoulder represents something of a `Holy Grail' Accurate 3D representation of segments requires at least three
in upper-limb biomechanics. non-collinear markers, or points. Additional markers are required
to define points of anatomical relevance. In the upper body, esti-
The `where',`who' and `how' mation of wrist and elbow movement is relatively simple as both
The Vicon 612 (Oxford Metrics, Oxford, UK) system at the joints can be represented by two degrees of freedom. However,
School of Sport Science, Exercise and Health was utilised to biomechanical modelling of the shoulder is complicated by its
track retroreflective markers (UWA model) placed on twelve three degrees of freedom as well as the high rotational veloci-
high performance able-bodied male tennis players and two top ties and large ranges of motion that punctuate its involvement
30 professionally ranked male wheelchair tennis players executing in functional tasks. Further, gimbal lock (where angles become
serves of varying type (i.e. flat serve and kick serve) and technique. ill-defined as axes coincide) is of real interpretive concern when
Twelve cameras, operating at 250 Hertz, minimised the prospect of shoulder joint motion is determined via the Euler angle flexion-
marker occlusion and optimised marker reconstruction during data extension, abduction-adduction and internal-external rotation
collection. Upper limb kinetics were calculated through inverse ZXY decomposition typically used to describe all other joint
dynamics, where segmental masses and moments of inertia were motion.10 Pilot work was thus undertaken to corroborate the
provided from the data of De Leva 5 and Clauser et al.6 ISB-recommended plane of elevation, elevation and internal-ex-
ternal rotation decomposition,11 and its accompanying spherical
reference system, as preferrable for computing more representa-
tive shoulder joint kinematics. Also, with soft tissue artefact
considered the largest source of error in 3D motion analysis,
a case study was needed to compare the coupling of different
marker/triad positions (i.e. the technical coordinate systems) and
the underlying humeral bone motion.
The analyses
Study 1: Similar shoulder joint kinetics developed dichotomous
3D racquet velocities in the high performance able-bodied flat
serve and kick serve. Where higher peak horizontal, vertical and
absolute racquet velocities were generated during the flat serve,
higher lateral velocities characterised the kick serve. The compa-
rable shoulder joint loading conditions nevertheless point to the
repetitive, long-term performance of either serve as relevant in
shoulder joint injury pathologies.
Study 2: Coordinative lower limb variation in the able-bodied
serve, encapsulated by specific front and back lower limb joint
kinematics was also shown to influence the development of flat
serve racquet velocity. Aided by a leg drive, high-performance
players generated similar absolute pre-impact racquet velocities
from both foot-up and foot-back service stances. Conversely,
22
the high performance tennis serve
less dynamic engagement of their lower limbs (i.e. the ARM The`where to from here' at the University of Western Australia About the author
serve: flat serves hit with minimal active ankle, knee and hip joint � Ongoing biomechanical examination to establish best marker
flexion-extension) saw players unable to generate commensurate
pre-impact absolute racquet velocities. Interestingly, comparable positions and processes of shoulder joint estimation as well
shoulder joint kinetics were inherent to the flat serve, irrespective as most meaningful shoulder joint representation, to further
of the noted lower limb kinematic variation. So, with differential enhance the calculation and interpretation of shoulder joint
absolute racquet velocities produced via similar shoulder joint motion in all overhead motions.
loads but divergent `leg drives', other links in the `kinetic chain' � Examination of shoulder mechanics (inclusive of electromyog-
may be more affected by variable lower limb involvement. raphy) in the flat, slice and kick serve performance of pre- and
post-pubescent high performance male and female players.
Study 3: In contrast to able-bodied serve performance, similar � Derivation of ball spin rate and axis during the high perfor-
peak pre-impact absolute racquet velocities were generated dur- mance serve of adult and junior players. Determination of the
ing the wheelchair flat serve and kick serve. Wheelchair serve key kinematic characteristics that help produce ball rotation.
tactics still demanded the development of higher peak pre-impact
horizontal and lateral racquet velocities during the flat serve and References
kick serve, respectively. Shoulder joint kinetics were consistent
across wheelchair serve type, but specific to the individual players; 1. Chandler TJ, Kibler WB, Stracener EC, Ziegler AK, Pace B. Shoulder strength,
likely varying with their level and severity of spinal cord injury. power, and endurance in college tennis players. Am J Sports Med 1992;20:455-8.
When expressed relative to absolute racquet velocity, both the
high-performance able-bodied and wheelchair players tolerated 2. McCann PD, Bigliani LU. Shoulder pain in tennis players. Sports Med
comparable pre- and post-impact shoulder joint loading profiles 1994;17:53-64.
such that related shoulder joint injury risk appears analogous
between populations. 3. Kibler WB. Biomechanical analysis of the shoulder during tennis activities. Clin
Sports Med 1995;14:79-85.
4. Elliott B, Fleisig G, Nicholls R, Escamilla R. Technique effects on upper limb
loading in the tennis serve. J Sci Med Sport 2003;6:76-87.
5. de Leva P. Adjustments to zatsiorsky-seluyanov's segment inertia parameters. J
Biomech 1996;29:1223-30.
6. Clauser CE, McConville JT, Young JW. Weight, volume and centre of mass seg-
ments of the human body. In: AMRL Technical Report 69-10. Dayton: Wright-
Patterson Air Force Base, 1969.
7. Knudson D. Intrasubject variability of upper extremity angular kinematics in the
tennis forehand drive. Int J Sport Biomech 1990;6:415-21.
8. Knudson DV, Blackwell JR. Variability of impact kinematics and margin for error
in the tennis forehand of advanced players. Sports Engineering 2005;8:75-80.
9. Mullineaux DR, Bartlett RM, Bennett S. Research design and statistics in biome-
chanics and motor control. J Sports Sci 2001;19:739-60.
10. Grood ES, Suntay WJ. A joint coordinate system for the clinical descrip-
tion of three-dimensional motions: Application to the knee. J Biomech Eng
1983;105:136-44.
11. Wu G, van der Helm FC, Veeger HE, et al. ISB recommendation on definitions
of joint coordinate systems of various joints for the reporting of human joint
motion--Part II: Shoulder, elbow, wrist and hand. J Biomech. 2005;38:981-92.
Machar is the Sport Science Manager for Tennis Australia. Previously, he worked
as a Lecturer in Biomechanics at the University of Western Australia, where he
continues to retain an Adjunct appointment.
From 2000-2004, he was the Assistant Research Officer for the International Ten-
nis Federation (ITF), based in Valencia, Spain. A Tennis Australia Level 3 Coach,
Machar's duties included coaching some of the world's best juniors, conducting
research on the game's professional elite, creating and delivering the ITF Level 3
course, and co-authoring several ITF publications. During that period, Machar also
filled the role of physical training advisor to former top 10 player, Greg Rusedski,
and was contracted by the Chinese Tennis Association to work with and establish
a strength and conditioning framework for the country's female elite (Li Na and
Jie Zheng).
Academically, Machar has completed a B.App.Sc. (Hons) in Human Movement
[RMIT], PG Dip in Elite Sport Coaching [Canberra], and in December 2006, a
PhD in Biomechanics [UWA].
Address for correspondence: Mreid@tennis.com.au
23
Original research
Tristan Barnett, Denny Meyer and Graham Pollard
Med Sci Tennis 2008;13(2):24-27
Applying match Abstract
statistics to A large database of tennis statistics is used to
calculate player match statistics for each court
increase surface. Analysis is carried out to determine
serving serving strategies to increase performance. The
results of the analysis could be used by players
performance and coaches to possibly increase serving perfor-
mance.
Introduction
There is a range of published material on the use of match statis-
tics/probabilities to increase serving performance. Gale1 used a
simple mathematical model to determine an optimal strategy for
serving in tennis. Norman2 used dynamic programming to de-
termine an optimal strategy of whether to use a slow or fast serve
on the first and second serve. George3 used a simple probabilistic
model to determine a serving strategy in tennis and stated that
the usual serving strategy may not be optimal. Professional tennis
matches were used as examples to support the claim. Gillman4
developed a similar analysis to serving strategies. Hannan5 also
analysed different serving strategies, with the added complexity
of the opponent returning the serve in such a way that the server
countered with a strong shot or was forced to hit a weak shot.
Pollard6 determined a method for finding the optimal risks that
should be taken by the server on the first and second serves.
In the above papers the effect of the receiver's receiving capacity
on the probability that the server wins a point on the first serve
and on the probability that he wins a point on the second serve,
is typically handled implicitly. Nowadays, with the availability of
substantial data on each player's receiving capacity (as well as on
each player's serving capacity), it is possible to address the effect
of the strength of the receiver on the server's first and second
serve probabilities explicitly rather than just implicitly. Thus, a
player's serving probabilities against one player can be different
from his/her serving probabilities against another. Correspond-
ingly, a player's best serving strategy against one player can be
different from the best serving strategy against another. Barnett
and Clarke7 showed how to predict serving and receiving player
statistics/probabilities prior to the start of a match. Their model
can be used to evaluate the optimal serving strategy for a player
against a particular opponent. Barnett and Pollard2 showed that
players' performances are affected by the court surface for both
men and women. Thus, a player's optimal serving strategy can
vary from opponent to opponent and from surface to surface. In
earlier studies, such variations were handled implicitly, and were
not clearly identifiable to the reader.
24
As an example of a player's optimal serving strategy varying years. The database is taken from the 6th August, 2007. The sur-
from one opponent to another, we consider the following. faces are categorized as grass, hard, indoor hard, clay, carpet and
Consider a typical professional man (player A) whose optimal acrylic. For simplicity hard and indoor hard are considered as one
serving strategy is typically a hard first serve and a softer surface. It is noted that acrylic will be played at the Australian
second serve with spin. If this player's opponent is equally as Open from 2008. At August 2007, there are no match statistics
good at receiving a first serve as receiving a second serve, it is recorded by the OnCourt database for matches played on acrylic.
clear that player A may just as well serve a second serve as a
first serve. On the other hand, if player A's opponent is very A program was written in SAS to calculate the average serving
much better at receiving a second serve than receiving a first
serve, it may be better for player A to serve two first serves and receiving statistics for each player on each surface. The
than to serve a fast first serve and a slower second serve. In
this paper we see how the merits of this potential strategy of serving and receiving statistics averaged across all matches on
two fast serves can be assessed statistically by a player about
to play a specific opponent. each surface was also calculated. Tables 1 and 2 below give these
This paper uses a large database as provided by KAN-soft (www. overall averages for men and women. The results indicate that
oncourt.info) to calculate player match statistics for each court
surface. The methods of the analysis could be used by players and women serve a higher percentage of 1st serves in play compared
coaches to increase potential serving performance.
to men for all four surfaces. However, the results indicate that
OnCourt database
The OnCourt database provides some match statistics since the men win a higher percentage of points on the first and second
2003 French Open. Not all the match statistics for the ATP and
WTA events are given. However the number of matches and serve compared to the women for all four surfaces. Overall, the
tournaments included in the database has increased in recent
results indicate that men win a higher percentage of points on
serve compared to women on all four surfaces. This agrees with
the results of Barnett and Pollard.8 The difference between
the percentage of wins on first serve for men and for women is
8.8%. The difference between the percentage of wins on second
serve for men and women is 5.5%. As the former value is greater
than the latter value, there is a suggestion or possibility that a
fast first and fast second serve strategy is more likely to be a rea-
sonable one in a men's match than in a women's match. >>
25
Table 1. Match statistics for men separated by court surface fijs = bis � djs + davs (1)
gijs = cis � ejs + eavs (2)
Statistic Grass Carpet Hard Clay where:
fijs = percentage of points won on first serve given that first serve
WinPercentage of 1st serves in play 61.9% 61.3% 60.0% 61.5% is in when player i meets player j on surface s,
73.0% 71.0% 67.1% gijs = percentage of points won on second serve when player i
Percentage of points won on first serve 74.1% 51.3% 50.9% 49.2% meets player j on surface s,
64.6% 62.5% 60.2% davs represents the average percentage of points won on return of
Percentage of points won on second serve 51.8% 27.0% 29.0% 32.9% first serve on surface s,
48.7% 49.1% 50.8% eavs represents the average percentage of points won on return of
Percentage of points won on serve 65.5% 35.4% 37.5% 39.8% second serve on surface s.
304 4319 3331
Percentage of points won on return on first serve 25.9%
Percentage of points won on return on second serve 48.2%
Percentage of points won on return of serve 34.5% A simple analysis can now be used to compare two serving strate-
gies. The first strategy is where a player serves a fast serve on the
Number of matches 928 first serve and a slow serve on the second serve. It is assumed that
for the data collected, players have always used a fast first serve
Table 2. Match statistics for women separated by court surface and a second slower serve. Even if this is not always the case, it
would appear to be a reasonable assumption for the following
analysis. Using this strategy, the percentage of points won on
serve is given by:
Statistic Grass Carpet Hard Clay
Percentage of 1st serves in play 63.1% 63.4% 62.1% 63.4% ais * fijs + (1- ais) * gijs
63.1% 62.0% 59.6%
Percentage of points won on first serve 65.4% 46.4% 45.3% 43.6% The second strategy is where a player serves a fast serve on both
57.0% 55.5% 53.5% the first and second serve. Using this strategy, the percentage of
Percentage of points won on second serve 46.1% 36.9% 38.0% 40.4% points won on serve is given by:
53.6% 54.7% 56.4%
Percentage of points won on serve 58.1% 43.0% 44.5% 46.5%
199 3432 2293
Percentage of points won on return on first serve 34.6% ais * fijs + (1- ais) * ais * fijs
Percentage of points won on return on second serve 53.9% Therefore, a player should use the second strategy if
Percentage of points won on return of serve 41.9% (1-ais) * ais * fijs > (1-ais) * gijs
Number of matches 881
which simplifies to
Serving Strategies ais * fijs > gijs
The players' serving and receiving statistics are defined as:
Example: Andy Roddick versus Rafael Nadal
ais = percentage of first serves in play for player i on surface s, Serving and receiving statistics for Andy Roddick and Rafael
bis = percentage of points won on first serve given that first serve Nadal are given in Table 3. Equations 1 and 2 are used to
is in for player i on surface s, calculate fijs and gijs, where davs and eavs are obtained from
cis = percentage of points won on second serve for player i on Table 1. The lack of matches played on carpet by both players is
surface s, noted. The results from Table 3 indicate that Roddick might be
dis = percentage of points won on return of first serve for player encouraged to serve fast on both the first and second serve when
i on surface s, playing Nadal on grass. However he should use a fast first serve
eis = percentage of points won on return of second serve for and slower second serve when playing Nadal on both hard court
player i on surface s. and clay. Nadal on the other hand should use a fast first serve and
slower second serve when playing Roddick on grass, hard court
The surfaces are defined as: s=1 for grass, s=2 for carpet, s=3 for and clay. This example illustrates the fact that it can be important
hard and s=4 for clay. for a player to identify the particular surface statistics for himself
and his opponent.
Combining player statistics is a common challenge in sport.
While we would expect a good server to win a higher propor- The above analysis indicates that Roddick might do slightly bet-
tion of serves than average, this proportion would be reduced ter when playing Nadal on grass by using two first serves rather
somewhat if his opponent is a good receiver. Using the method than using a first serve and a slower second serve. The effect how-
developed by Barnett and Clarke7 we can calculate the combined ever is not statistically significant. Nevertheless, Roddick might
percentage a player wins on his/her first and second serve for do well to mix his first and second serve when serving a second
each surface. The equations are given as follows: serve to Nadal. He would appear to have little to gain or lose sta-
26
Table 3. Serving and receiving statistics for Andy Roddick and Rafael Nadal
Andy Roddick Rafael Nadal
Statistic Grass Carpet Hard Clay Grass Carpet Hard Clay
ais 0.67 0.69 0.66 0.57 0.69 0.70 0.66 0.71
bis 0.82 0.73
cis 0.82 0.78 0.59 0.55 0.76 0.63 0.75 0.72
dis 0.29 0.28
eis 0.56 0.43 0.51 0.48 0.57 0.53 0.59 0.58
fijs 0.800 0.639
gijs 0.28 0.23 0.551 0.458 0.28 0.26 0.31 0.42
ais * fijs 0.528 0.364
Matches 0.47 0.48 99 17 0.53 0.50 0.53 0.60
0.799 0.790 0.739 0.670 0.750 0.769
0.512 0.417 0.582 0.537 0.571 0.608
0.535 0.545 0.510 0.469 0.495 0.546
37 3 24 4 72 72
tistically by such a strategy, but he might gain a moderate amount About the authors
from the `surprise' factor in such a strategy. Similar analyses to test
for significance can be performed for the other surfaces. However,
it is clear that two first serves will not be such a good strategy for
Roddick in the case of clay surfaces.
Conclusions Dr. Denny Meyer is a Senior Lecturer in Statistics at the Swinburne University
The results indicate that separating player match statistics into of Technology. She has co-authored two books and has published upward of 50
different court surfaces can be useful (for some players against articles in refereed journals. She is an applied statistician, working in areas such as
some other players on particular surfaces) in making decisions sport statistics, management, tourism, mineral processing, advertising, agriculture
on serving strategies. An example where one player might benefit and social research.
by serving two fast serves has been given. The method of analysis
could be used by any player or coach to see whether serving per-
formance might be enhanced during a forthcoming match. Thus,
this approach could be quite a valuable tool for some players.
Player match statistics could be used in other applications. For
example, match statistics separated by court surface could be used
by television broadcasters as a guide to likely match outcomes
and comments on strategies.
Acknowledgement Dr. Tristan Barnett is an Adjunct Research Fellow in sports statistics at Swin-
The authors would like to thank KAN-soft for providing the burne University of Technology. He has written several published papers, given
database for calculating serving and receiving statistics. presentations at international conferences and has a PhD in tennis modelling. He
has appeared on many occasions in the media including SEN sports radio and
References 3RRR sports segment"Run Like You Stole Something". Tristan currently works as
a gaming mathematician for Sportsbet21 Pty Ltd.
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Science in Sports. Ladany SP, Machol RE, Morrison DG (eds). Amsterdam:
North�Holland Publishing Company, 1976:125�36. Emeritus Professor Graham Pollard is a former professor of applied statistics
6. Pollard GH, Pollard GN. Optimal risk taking on first and second serves. In: and pro-vice-chancellor of the University of Canberra, Australia. He is a former
Tennis Science & Technology 3. Miller S, Capel-Davies J (eds). London: Interna- first grade tennis player and state squash champion, has a PhD in statistics from
tional Tennis Federation, 2007:273-80. the Australian National University, and has international research publications in
7. Barnett T, Clarke SR. Combining player statistics to predict outcomes of tennis tennis, squash, theoretical statistics, maths education and physics.
matches. IMA J Management Math 2005;16:113-20. Address for correspondence:
8. Barnett T, Pollard G. How the tennis court surface affects player performance Dr. Tristan Barnett, Faculty of Life and Social Sciences, Swinburne University of
Technology, John St, Hawthorn, VIC 3122 Australia
and injuries. Med Sci Tennis 2007;12(1):34-7.
Website: www.swin.edu.au/sport
Email: strategicgames@hotmail.com 27
Original research
Janet A. Young
Med Sci Tennis 2008;13(2):28-31
Australian Abstract
Elite junior tennis players' perceptions of the
elite tennis importance of mental skills were investigated in
a study commissioned by Tennis Victoria. Eight
juniors' junior boys aged 13 to 17 years and seven girls
aged 12 to16 years comprising an elite training
perceptions squad at Melbourne Park responded to a ques-
tionnaire. Reponses to ratings of the importance
of the of mental and physical factors, and key mental
importance skills for success were recorded, together with
the time devoted to mental preparation prior to
important matches and explanations for match
losses. While mental factors and skills were
of mental strongly endorsed, no gender differences were
found in these endorsements or in the time
skills devoted to mental preparation. Losses in impor-
tant matches were generally attributed to mental
factors. Results were interpreted in terms of the
maturity of players and shared exposure to the
State coach's training methods and program.
Future directions in tennis mental skills research
are highlighted.
Introduction
In a recent publication, Weinberg1 suggests that the challenge
for most tennis players is to identify, and adopt, key elements
which facilitate playing at one's best on a consistent basis. To this
end, Weinberg2 suggests mental factors are paramount, citing:
(a) Jimmy Connor's contention that tennis is 95% mental at the
professional level; and, (b) the results of a survey with coaches
and players that found tennis success was considered at least
50% (and as high as 80- 90%) mental. In further survey findings,
Weinberg2 reports that, although players generally attributed
losses to mental factors, players devote no time, or very little time
(a few minutes), preparing themselves mentally for matches.
Key words:
elite tennis juniors, mental skills, mental skills
training
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In terms of teaching mental skills to players, Gould et al.3 suggest
that tennis coaches should play a key role (as a player's access to a
sport psychologist may be restricted and coaches are generally the
first, and most accessible, contact point for players). According to
these authors, this role for coaches is proving to be a challenging
one, with many coaches lacking requisite training in, and knowl-
edge of, mental skills training. As concluded by these authors,
"little is known about helping coaches develop mental skills in
their athletes" and more research on mental skills in tennis is war-
ranted.
With few studies conducted to date to address mental skills ability to control one's nerves and anxiety; (d) concentration; and,
development and training with children and young adoles- (e) love and interest in tennis. In addition, participants reported
cents,4-6 the aim of this study was to examine elite tennis juniors' on how much time they devoted to mental preparation before an
perceptions of the importance of mental skills for success and, important match. The qualitative measure in the questionnaire
further, to examine for gender differences in these perceptions. As consisted of asking participants to nominate reasons for their
such, this study complements research with adult elite athletes losses in important matches.
and coaches as to their perceptions of the importance of mental
skills.7-8 In these peak performance studies, a kaleidoscope of Procedure
mental skills were found to be associated with success, with key After receiving informed consent from players' parents, the inves-
skills embracing focused attention, feelings of confidence, ability tigator met with participants prior to a training session at Mel-
to control nerves and anxiety, commitment and dedication.8 bourne Park. The investigator outlined the study's purpose and
advised participation in the study was voluntary, there was with
In this exploratory investigation of elite juniors' perceptions of the no requirement for players to identify themselves in responding
importance of mental skills for success it was hypothesised that: and there were no correct, or incorrect, answers. All participants
1. Elite junior players would rate the importance of mental fac- completed the questionnaire within 20 to 30 minutes.
tors for success higher than the importance of physical factors Data Analysis
and there would be no gender differences in these ratings; To analyse the quantitative data, a number of inferential statistics
2. Elite junior boys and girls would rate the same the importance was conducted. Specifically, a series of seven Mann-Whitney
of key mental skills for success; U-tests were conducted to examine for differences in: (a) ratings
3. Elite junior boys and girls would devote similar time to mental of importance of physical and mental factors; and, (b) ratings
preparation prior to important matches, and, time devoted to of five key mental skills by gender. An independent t-test and a
mental preparation prior to matches would increase with a Pearson's product moment correlation were also conducted to
player's age; examine for gender differences in the amount of time devoted
4. Elite junior players would attribute losses in important games to mental factors prior to matches and the relationship between
to mental factors. the amount of time devoted to mental preparation and age of
participants respectively.
Method
Participants To analyse the qualitative data, an inductive content analysis
An elite squad of eight boys aged 13 to 17 (mean 16.1) years and
seven girls aged 12 to 16 (mean 14.8) years participated in the of participants' accounts for their losses in important games
study. The juniors, who were the top two ranked players in their
age groups in the State, trained twice weekly at Melbourne Park, was conducted. In a popular procedure adopted by qualitative
Melbourne, Australia under the guidance of the State coach. The
coaching program conducted by the State coach did not include researchers,10 key words, phrases or statements (referred to as
any formal mental skills training sessions.
`raw data themes') were identified in participants' narratives. Raw
Materials
Participants completed a self-report instrument (questionnaire) data themes sharing explicitly similar meaning were subsequently
that was developed for the purposes of this study and consisted
of both quantitative (n = 7) and qualitative (n = 1) measures. grouped into higher order (general) dimensions. In a final pro-
The quantitative measures consisted of asking participants to rate
the importance of the physical (e.g. fitness) and mental (mind, cedure, these general dimensions were classified as physical (e.g.
thinking) aspects of tennis for success on a 5-point Likert scale9
(anchored where 1 = not important at all to 5 = extremely im- physical fitness), mental (e.g. motivation) or other (e.g. weather,
portant). Using the same 5-point Likert scale, and adapting Wil-
liams and Krane's8 psychological profile of a sporting champion, court conditions) factors in accord with Weinberg's1,2 descrip-
participants were also asked to rate the importance for success of:
(a) success of determination and commitment; (b) self-belief; (c) tions of these factors. >>
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Results Players' attributions for losses
Mental skills and success The results of the content analysis of players' explanations for
Participants' ratings of the importance of physical and mental losses in important matches are presented in Table 3.
factors for success are presented in Table 1.
Table 3. General dimensions of factors cited by elite juniors (by
Table 1. Mean ratings by elite juniors (by gender) of the im- gender) for losses in important matches
portance of physical and mental factors for success in tennis on
Likert scale
Factor Mean rating: Mean rating: General dimension: General dimensions:
junior boys junior girlseach drill junior boys junior girls
Physical 4.75 4.71 � Loss / lack of concentration � Loss / lack of concentration
Mental 4.88 4.71 � Motivation problems � Lacked self-belief
� Inability to control nerves � Inability to control temper
� Lacked physical skills � Lacked physical skills
� Inappropriate tactics
A Mann-Whitney U-test revealed no significant differences in
participants' ratings of the importance of physical and mental The classification procedure on the nine general dimensions
factors for success (Mann-Whitney U = 59.5, p>0.05). listed in Table 3 revealed the majority (78%) of dimensions
were mental factors (with the one exception of the dimension of
Participants' ratings of the importance of five mental skills and lacked physical skills).
attributes for success are presented in Table 2.
Discussion
Table 2. Mean ratings by elite juniors (by gender) of the impor- In summary, the study found that elite junior players:
tance of key mental skills and attributes for success* 1. Considered physical and mental factors to be equally impor-
Mental skill Mean rating: Mean rating: tant for success, with no gender differences in these percep-
junior girl tions evident;
and attribute junior boy 2. Strongly endorsed the importance of key mental skills and
4.86 attributes - determination and commitment, self confidence,
Determination and 4.71 ability to control nerves and anxiety, concentration, love and
interest in tennis � with no gender differences in these percep-
commitment 4.75 4.57 tions evident;
4.86 3. Spent between 1-30 minutes mentally preparing prior to
Self confidence 4.88 4.42 important matches, with no gender differences evident in the
time devoted to mental preparation by players;
Ability to control 4. Nominated an array of factors (e.g. choking, attack of nerves,
a lack of motivation and self confidence) to explain losses in
nerves and anxiety 4.50 important matches. The majority (78%) of nominated factors
were mental ones, although a lack of physical skills was a shared
Concentration 4.62 general dimension of factors across elite junior boys and girls.
Love and interest in tennis 4.88 It was an aim of the study to examine for gender differences in
elite juniors' perceptions of mental skills, and it is noteworthy
* adapted from Williams and Krane8 that no gender differences were found across a number of mea-
sures. This finding suggests there may have been a comparable
A series of five Mann-Whitney U-tests revealed no significant level of maturity shared by the elite junior boys and girls in this
differences between junior boys' and junior girls' ratings of the study. It is also possible that the finding of no gender differ-
importance of each of the five skills and attributes listed in Table 2. ences arises as a consequence of all players, as members of an
elite training squad, sharing a common (or similar) training and
Mental preparation time coaching program conducted by the State coach.
In terms of time devoted to mental preparation before an
important game, junior boys reported spending between 1 to 30 As such, the study's findings suggest that elite junior players
minutes (mean 12.5), compared with 10 to 20 minutes (mean possessed an acute awareness of the importance of mental skills
18.9) reported by junior girls. An independent t-test revealed and attributes for success. While this awareness of the impor-
no significant differences between junior boys and junior girls in tance of mental factors did not differ significantly from players'
terms of their mental preparation time (t (13) = -1.5, p>0.05) perceptions of the importance of physical factors, a set of five
and a Pearson's product moment correlation revealed no signifi-
cant relationship between mental preparation time and age of
player (Pearson's product moment = -0.16, p>0.05).
30