Science in Tennis

June 2008 • volume 13 • number 2 medicine and science in tennis

• Rolling for recovery

• Meet the expert: Dr. Gary Windler

• Tennis training

• PRO U™ Player Orientation

• Best serving strategy

Chair www.stms.nl Moroe BEPPU, MD www.stms.nl Congress Organizer Chairman & Professor Department of Orthopedic Surgery St. Marianna University School of Medicine Journal of STMS in co-operation with: ITF • ATP • Sony Ericsson WTA Tour Kawasaki, Japan ISSN: 1567-2352 Medicine and Science in Tennis is a Journal produced by the Society for Tennis Medicine and Science (STMS) in co-operation with the ITF, the ATP, and the Sony Ericsson WTA Tour, and is issued three times a year (February, June, and October). Medicine and Science in Tennis is listed in Altis, Free Medical Journals, MedNets, NewJour, Sponet and SIRC Sports Discus. Th e International Board of the STMS: President: Marc R. Safran, San Francisco, CA, USA E-mail: [email protected] Vice-President: Javier Maquirriain, Buenos Aires, Argentina Message from the President E-mail: [email protected] Secretary/Treasurer: Bill Durney, San Francisco, USA E-mail: [email protected] Membership Oﬃ cer: Todd S. Ellenbecker, Scottsdale, AZ, USA Dear Members, E-mail: [email protected] Past-Presidents: Babette M. Pluim, Ede, the Netherlands Per A.F.H. Renström, Stockholm, Sweden W. Ben Kibler, Lexington, KY, USA Babette Pluim, the founding and current editor of the STMS journal, Additional Members: Peter Jokl, New Haven, CT, USA Bernard Montalvan, Paris, France Associates to the Board: Miguel Crespo, Representative of the ITF has decided to step down after 13 years in offi ce so this will be the Kathy Martin, Representative of the Sony Ericsson WTA Tour Gary Windler, Representative of the ATP last STMS journal she is editing. Once again, this issue demon- Honorary Members: Irving V. Glick, Great Neck, NY, USA Savio L-Y Woo, Pittsburgh, PA, USA strates the very high standard our journal has reached as a result North American Regional Committee: of her tireless eff orts and we owe her a very big “Th ank You”! Chairman: Marc R. Safran, San Francisco, CA, USA Neeru Jayanthi, Chicago, IL, USA Peter Jokl, New Haven, CT, USA W. Ben Kibler, Lexington, KY, USA Th is edition has several original articles in all disciplines of Carol Otis, Portland, OR, USA E. Paul Roetert, Key Biscayne, FL, USA tennis medicine and science. Th ere are articles on the adoles- Savio L-Y Woo, Pittsburgh, PA, USA cent athlete, mental health and psychology, and optimisation European Regional Committee: Chairman: Giovanni di Giacomo, Rome, Italy Gilles Daubinet, Paris, France of performance through the use of statistics. Th ere are medicine Hans-Gerd Pieper, Essen, Germany Babette Pluim, Ede, the Netherlands papers on imaging of os acromiale and the prevention of ankle Angel Ruiz-Cotorro, Barcelona, Spain Michael Turner, London, United Kingdom sprains, both important topics as the fi rst is a bit of a controversial, South American Regional Committee: but signifi cant issue, and the other due to the great frequency of ankle Chairman: Rogerio Teixeira Silva, São Paulo, Brazil Javier Maquirriain, Buenos Aires, Argentina sprains in tennis. Th ere are tips for coaches, and information about Scientifi c Committee: what the professional players are learning, in the WTA article on the Chairman: J. Chandler, Jacksonville, AL, USA Bruce Elliott, Perth, Australia Players’ Pro University about professional life and life after tennis. W. Ben Kibler, Lexington, KY, USA Karl Weber, Cologne, Germany Savio L-Y Woo, Pittsburgh, PA, USA Continuing in the series of Meet the Expert, we have included an interview with Gary Educational Committee: Chairman: Neeru Jayanthi, Chicago, IL, USA Peter Jokl, New Haven, CT, USA Windler, a member of the ATP Medical Team, clinician and active researcher of issues W. Ben Kibler, Lexington, KY, USA Kathy Martin, Melbourne, Australia relating to the professional tennis player. Further, there are book and DVD reviews about Piotr Unierzyski, Poznan, Poland Gary Windler, Summerville, SC, USA tennis medicine and science to help our readership evaluate what they may want to use to Editorial Board: further investigate areas of tennis medicine and science. Editor-in-Chief: Babette M. Pluim, Ede, the Netherlands E-mail: [email protected] Todd S. Ellenbecker, Scottsdale, AZ, USA Neeru Jayanthi, Chicago, IL, USA Lastly, a conference calendar of upcoming tennis related meetings (in addition to review Javier Maquirriain, Buenos Aires, Argentina Maarten Moen, Amsterdam, the Netherlands of the most recent tennis science and technology meeting) is provided, including the Rogerio Teixeira Silva, São Paulo, Brazil Bert J.G. van Weelde, Th e Hague, Netherlands two upcoming STMS meetings. Th ere is the North American Regional Meeting being Gary Windler, Summerville, SC, USA held August 1-2, 2008 in Cincinnati during the ATP tournament and hosted by Neeru Editorial Assistant: Anne Meredith, Wakefi eld, United Kingdom Jayanthi and Robert Rhoades. Additionally, the World Congress of the STMS will be held Subscriptions and Membership: Todd S. Ellenbecker in Tokyo, Japan during October 2-4, 2008, hosted by Moroe Beppu. Th e world congress Physiotherapy Associates Scottsdale Sports Clinic promises to be a fantastic meeting, with three concurrent sessions, including work shops for Scottsdale, AZ 85258, USA E-mail: [email protected] trainers, debate sessions, current concepts and some of the newest, exciting original research Annual Subscription fees due 1st January 2008 in tennis medicine. Full membership: $175.00 Student membership $100.00 Delegated Publisher: Once again, many thanks to Babette for all her hard work over the last 13 years. Th e TopNautic Media Onder de Bomen 7 STMS Journal is a magnifi cent legacy of her ongoing eff orts to improve the delivery of 6871 CG Renkum Th e Netherlands Phone +31-317-350728 sports medicine education to our tennis community. E-mail [email protected] Design: Leon van Loon, Liessel, the Netherlands I hope to see you in Cincinnati and Tokyo! E-mail: [email protected] Cover photo: Maaike Smit, Emmeloord, Netherlands Sincerely, Photography: Jeff and Manuela Davies, Orlando, FL, USA www.doubleXposure.com Marc R. Safran, MD Circulation: 2,000 President STMS Webmaster: Vincent ter Maat, Wageningen, the Netherlands E-mail: [email protected] Website: http://www.stms.nl Disclaimer: Th is 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 medicine and Contents 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 U™ 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

The best kept secret to maximising your perfor- Rolling mance is simple: “Recover better” according to tennis performance trainer Allistair McCaw. In this for article Alistair explains his views on the potential benefits of using a simple piece of foam to optimise recovery and recommends eight specific foam- recovery 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 performance. Your muscle resembles a rubber band and the further you 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, Recovery is the result will be increased power and improved performance. I believe that the foam roller is one of the most effective, all-around self-maintenance tools you will find, as it not only probably one of releases chronic muscular tension and pain (caused by playing or performing movement), but can actually restructure your skeletal system so that it aligns more positively with gravity. It is simple to the most overlooked 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 aspects in an 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 athletes’ program 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 • increases flexibility and joint function • speeds up the recovery process recovery the faster • is portable, light (weighs less than 500grams) and easy to travel with • limits the costs of a regular massage your progress will be

Your turn! I have put eight exercises together specifically for tennis players. Place your body on the roller and slowly roll up and down (for These exercises cover all the major muscle groups involved in the about 30-45 seconds) along the muscle group you are targeting. game. Make these exercises part of your regular cool-down routine. I have a basic rule: If it hurts, it needs more attention. So if you Perform them directly after your training session or match (after find a particularly tight area, pause on that spot. Putting pressure a cool-down jog or spin on bike, but before stretching) to maxi- on a tight area can help release the tissue. 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 position 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. Latissimus dorsi Position yourself side lying with arm outstretched and foam roll placed in axillary area. Th umb 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 shoulder to clear the shoulder blades across the thoracic wall. While maintaining abdominal drawn-in position, raise hips until unsupported. 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 fl exibility. 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! About the author

Tennis performance specialist Allistair McCaw is founder of Performance Tennis which specializes in tennis-specifi c conditioning training. Allistair has worked with no less than 6 top 20 tennis players including Jelena Dokic, Nathalie Dechy, Michaella Krajicek and Dinara Safi na. He has also trained the world numbers one a n d t w o s q u a s h p l a y e r s N i c o l D a v i d ( w o r l d c h a m p i o n ) a n d N a t a l i e G r i n h a m .

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. Th e 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). Th e 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. Th e 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. Th e 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. Th is 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 eff ective playing time) were play, after 30 minutes of play and at the completion of the match. involved in the control of core body temperature. Th e 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 modifi ed for loss assessment. Drink bottles were weighed at the same times improved prediction in tennis. to account for fl uid intake. During the change of ends after every six games, players indicated subjective responses of perceived exertion, thermal comfort, sweatiness and a rating of conditions (thermal sensation). Notational analysis was conducted throughout matches to assess activity patterns and workload.

Results: Air temperature ranged from 14.5 to 38.4°C, relative humidity ranged from 21.8 to 73.7% and WBGT ranged between 13.5 and 29.2°C. Mean point duration was 5.8 ± 1.3 s and eff ective playing time (the proportion of the match spent in play) averaged 23.7 ± 5.2 %. Th is equates to a work to rest ratio of approximately 1 : 3.5. Positive associations were found About the author for the change in rectal temperature with both point duration (P < 0.001) and eff ective playing time (P < 0.05). Heart rate was also positively correlated with point duration (P < 0.0001) and eff ective playing time (P < 0.05). Rectal temperature averaged 38.5 ± 0.4°C (62% VO2max) and mean heart rate was 136.8 -1 ± 13.6 beats.min (66 % VO2max). Both rectal temperature and heart rate were unaff ected by the two components of the Sarah Morante has completed a Bachelors degree and a PhD (April 4th, 2008) in current Extreme Heat Policy (air temperature and Wet Bulb the School of Exercise and Sport Science at Th e University of Sydney. She currently operates a sport and fi tness consultancy company that ranges from providing Globe Temperature), even in conditions exceeding the thresholds lecturing services to higher education providers including Sydney University and for each index (35°C and 28°C, respectively). Skin temperature sporting/fi tness organizations. 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). Th ermal comfort declined with increasing rectal temperature (P < 0.03) and skin temperature (P < 0.0001). Both point duration (P < 0.002) and eff ective playing time (P < 0.0002) were reduced as conditions were rated increas- ingly diffi cult. 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

PRO U™ is the Sony Ericsson WTA Tour’s umbrella Introduction institution for education. The PRO U™ staff is responsible for educating players and their sup- to PRO U™ port teams from the onset of their professional careers and covers development in three core domains: Player • Human Development • Tennis Development Orientation • 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 U™ 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 U™ 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 U™ programs be made available to more athletes and PRO U™ 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 U™ programs will be available to players online. skill-building. The Rookie Phase is the introductory phase of PRO U™ 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, • In 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- • In a Grand Slam singles (main draw or qualifying). ual and the Tour at-large. The on-line modules are divided into three or more interactive History of PRO U™ lessons, to ensure the information is comprehensively covered PRO U™ programs came about as a result of the 1994 Age Eli- in manageable doses. The on-line Player Orientation course gibility Commission (now the PRO U™ Advisory Panel) report, includes audio, video, picture images and text. At the end of each which identified the major stressors in women’s professional lesson, players must pass an on-line quiz and evaluate the lesson tennis and made complementary recommendations. The 1994 content. Players must successfully complete each on-line course Age Eligibility Commission report findings strongly indicated within 90 days of eligibility. The first modules to be launched in the need for developing skills and train these young athletes to 2008 include: succeed in the professional environment. Accordingly, the Player Orientation was expanded from a four-hour group session over- Copyright WTA Tour Inc. view of the Tour to the system now in place. The current model is 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 U™ 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. The PRO TMU program’s have had a positive effect on the health and well-being of the players

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 Tour, why PRO U™ exists, how the Tour and ITF/other tennis Conduct, Medical Time-Out).2 Practical skills include: the governing bodies work together, practical guidance on entry/ process of the draw and the daily schedule of play, and proper withdrawal procedures, how the rankings work and the Age entry and withdrawal procedures. Eligibility Rule.2 • Player Relations – players are introduced to membership and Athlete Safety & Security benefits for members, the pension program, the importance of o Safety at home, safety during travel, safety at tournaments; player meetings and the role of Player Council and the gover- Tour initiatives to promote safety (e.g., code of conduct for nance of the Tour and player news and information. Practical player support team members, athlete assistance programs and activities include: attendance at a player meeting and meeting services) and the Tour’s cumulative responsibility to promote a with a Player Council representative. safe and healthy environment. • Communications – players learn how the media works as a Rookie Hours business and how media grows the sport and helps to connect o An in-depth, interactive lesson reviewing individual Tour players with the fans, and influences the image of individual departments. Players learn: the purpose and role of each de- players, tournaments and the Tour. Practical skills include: partment; critical rules specific to that department; credentials, review of advice from former players, attendance at a press qualifications and licensure of staff members in departments; conference and a review of interview techniques. and practical skills related to the topic in each lesson. The goal is that players will develop the relevant professional skills neces- • Marketing & Sponsorship – players learn about the sponsor- sary to succeed in the Tour environment. ship agreements of the Sony Ericsson WTA Tour, players’ roles with sponsors and the important relationship between players The following departments are covered in the Rookie Hours: and the community, charities and fans. Practical activities in- • Sport Sciences & Medicine – players are introduced to the clude: important advice on self-promotion and marketing, meet training (treatment) room; the physical therapy and massage the sponsors and participate in sponsor activities. therapy personnel; how and where to access health services on- and off-site; Tour rules pertaining to health (example: Extreme • Athlete Assistance – aims to enhance players’ health, well- Heat Condition Rule);2 biomechanical services, nutrition being and safety. Players learn about the services, resources and and hydration services; and injury prevention practices, like preventative strategies available to help manage the environ- the annual physical. Practical skills include: blister treatment mental and life stressors, improve overall coping skills and and prevention, contents of a first aid kit, and proper dynamic enhance performance. Practical activities include: an on-line warm-up and recovery techniques. tour of the Achieve Solutions website,3 the Athlete Assistance >>

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.

• Tournament Operations – players are introduced to the be- Th omas Livengood graduated with a Bachelors of Arts in Sociology and Russian hind the scenes functions of tournaments and how players and Language and Literature from Kent State University. Tom joined the Sony Erics- son WTA Tour’s PRO U™ Department as Coordinator, in October 2003. Tom’s tournaments work together for maximum eff ect. Th ey learn the primary responsibilities as Coordinator, PRO U™ include development, tracking responsibilities of tournament staff and volunteers, the details and maintenance of the Orientation program and monitoring the progress of players through the requirements of the Rookie Phase. His duties include working of tournament marketing, fi nance and administration, and the with players and their support teams (coaches, parents, agents) to help them learn importance of the tournament profi ting to help grow the sport, about the professional tennis environment. He also assists with other Sony Erics- and player prize money. Practical activities include: a visit to the son WTA Tour educational initiatives such as the Coach Symposium and Junior forums. volunteer tent or ticket booth, a sponsor walk-through and a Before joining the Tour, Tom’ s past professional experiences include cross-cultural private tour of the facility. orientation and curriculum development and teaching international high school exchange students. He also lived in Russia for more than three years in the 1990’s, and is fl uent in conversational Russian. Transition from the ITF to the Sony Ericsson WTA Tour At the junior level, the International Tennis Federation has developed the ITF Junior Tennis School with a goal to help the junior tennis community develop as humans and tennis players. Tennis training: Th is enterprise complements Tour initiatives and uses a blend of enhancing on-court on-line education and on-site forums, which introduce players Pages: 245 to topics including sport sciences, health, safety, media training Price: 19.95 US$ and anti-doping. PRO U™ personnel participate in One Game ISBN-13: initiatives, such as the Wimbledon Junior Forum, which is a 978-0-9722759-7-2 collaborative seminar led by the ITF with the Sony Ericsson WTA Tour and the ATP. Past and present members of the PRO U™ Advisory Panel are also actively involved in the ITF Junior Ashley Keber graduated with a Bachelors of Arts in English from the University 4 of Florida, Phi Beta Kappa. She has worked with the Tour since 1997, where she Tennis School. has been the PRO U™ department head, overseeing such programs as the Age Eligibility Rule, Player Orientation, media training and mentor program. She has served on the Women’s Sports Foundation Career Development task force, Conclusion the Athlete Development steering committee and has been a featured speaker at Th e purpose of the Player Orientation is to educate players about coaching conferences and an invitee to the annual Board meeting and symposium their responsibilities on the Tour and gain an understanding of for National Center for Human Performance. Prior to joining the Sony Ericsson WTA Tour, Ashley was a broadcast liaison for the 1996 Atlanta Olympic Broad- what it means to be a professional. Th e interactive on-line course casting group, networks which included Eurosport, BBC, ZDF, Australia 7 and explains and brings to life the building blocks of the business. NBC. While attending university, she was an instructor and residence counsellor for the UF-Nike Summer Tennis program. Th e 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. Th e Tour is committed to and off ers professional development programming that is dynamic, eff ective and relevant to players’ lives and careers. Th e Panel continues to meet annually to provide guidance on all PRO U™ programming initiatives. Th e PRO U™ team strives to create, innovate and execute the best training possible for players, so they can maximize their opportunities and fulfi l 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. Th e 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 offi cial 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 3. Value options. Achieve solutions. [homepage on the Internet]. © 1999-2007. College of the Arts. She joined the Sony Ericsson WTA Tour as a Primary Health 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: Th e International Tennis Federation’s Address for correspondence: fl agship magazine. 2007;32:26-9. Kathy Martin, Sony Ericsson WTA Tour, One Progress Plaza, Suite 1500, St. Petersburg, FL 33701, USA. E-mail: [email protected] 12 Book review

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 defi nitely 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

Th is 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: enhancing on-court Pages: 245 Price: 19.95 US$ About the authors ISBN-13: Dr. Mark Kovacs obtained a top 100 ITF junior ranking, won a US “gold-ball,” 978-0-9722759-7-2 and competed in many international tournaments including the US and Australian Open before attending Auburn University where he was an All-American and NCAA doubles champion. He has combined researched scientifi c evidence in 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 At fi rst sight “Tennis training” by Mark Kovacs, Britt Chandler and professional athletes. In February of 2008, Dr. Kovacs was named the Manager of Jeff Chandler could be just one of the many books about tennis United States Tennis Association Sport Science in Boca Raton, Florida. training. However, after studying it in more detail, it turns out to be a ‘must-have’ book for tennis medical and performance specialists. Tennis is an individual and a technical sport. Because of the physiological and technical aspects of tennis, we must train the body in many areas. A player has to develop 4 sides: the player has to specifi cally develop technical, tactical, mental and physical strengths. Within the physical training there are also many aspects that need to W. Britt Chandler has a master’s degree in exercise science from Auburn University be developed. Th e authors have succeeded with the book “tennis train- and played collegiate tennis. He is certifi ed as both a strength and conditioning spe- ing” to write a manageable and synoptic book for players and coaches. cialist (CSCS) and certifi ed personal trainer (NSCA-CPT). He also is a certifi ed Th e book focuses on physical training in the sport of tennis. In tennis coach through the USPTA. He currently works as both a tennis coach and strength conditioning specialist with some of the top juniors in the country. Britt is general it does not give any new information. It contains summaries also the editorial assistant for the Strength and Conditioning Journal and has con- of existing literature and references to known facts. However, what tributed book chapters and presentations on tennis specifi c research and training. makes this book so good is the information about training principles, training laws, periodisation and experiences from the practices, focused on tennis. Supported by science, clearly described and fi lled with pictures the book is fi lled with tennis-specifi c exercises. “Tennis training” makes physical training in tennis easy to understand 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 Dr. T. Jeff Chandler has over 20 years experience as a tennis researcher and sports science consultant, advisor, and author for many tennis organizations including the the large number of specifi c exercises. Athletes gain in detail insight USTA, USPTA, ITF, STMS and PTR. He has over 100 scientifi c publications, in what happens with their body during training, what exercises are book chapters, and presentations relating to tennis training and performance. He is currently Department Head of Health, Physical Education & Recreation at really important and why physical training is such an important part Jacksonville State University, Jacksonville, Alabama, and is the Editor in Chief of of their development. Parents can also benefi t from this information. the Strength and Conditioning Journal published through the National Strength Th ey are usually further removed from the practice and this way and Conditioning Association. Dr. Chandler is certifi ed with distinction as both a CSCS*D, and NSCA-CPT* D. He is a Fellow in the American College of Sports Medicine (FACSM) and a Fellow in the National Strength and Conditioning Association (FNSCA). 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 adults and youngsters. The presentation of muscle and tendon trauma largely depends on the patient’s sports-related age: in youngsters the skeleton is weaker than in adults, whereas their ligaments and tendons can muscle and withstand more force.1 Therefore, skeletal lesions, more specifically those of the physis, are common tendon injuries in children.1 The type of sports activity determines the nature of the lesion. Most commonly apophyses of the hip and pelvis are subject to avulsion in children and fractures in youngsters, and in tennis the pelvis is the most likely site to be affected.2 Lesions can be adolescents 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. Most 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 avulsion fracture at the inferior anterior iliac spine in a 15-year-old male tennis player. Axial CT demonstrates an irregularly delineated bony mass at the insertion Evert Vandervliet, MD is resident radiology at the University Hospital Antwerp, of the left rectus femoris muscle at the AIIS, due to unremodelled callus for- UZA and the AZ St. Maarten in Duff el-Mechelen, Belgium.

mation. In the absence of history of previous sports trauma, this may mimic About the authors a malignant bone tumor.

Subacute and chronic avulsion fractures or insertional overuse lesions typically involve the proximal attachments of the gracilis (gracilis-adductor syndrome) and adductor muscles (chronic proximal adductor insertion avulsion syndrome) or distal adductor brevis muscle attachments (chronic distal adductor insertion Filip Vanhoenacker, MD, PhD is radiologist at the University Hospital Antwerp, avulsion syndrome or thigh splints).5 UZA and the AZ St. Maarten in Duff el-Mechelen, Belgium and guest lecturer at the University of Antwerp. Radiographic fi ndings 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 demonstrates 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 Th us MRI may demonstrate a variable signal according to the reparative stage of the lesion (either due to Annemiek Snoeckx, MD, is senior resident at the University Hospital Antwerp, UZA. 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 fragments cause prolonged complaints.4

Conclusions 1. In the adolescent, the physis is particularly susceptible to trauma. 2. Th e nature of the sport determines the pattern of injury. Lesions due to tennis usually involve the inferior and superior Jan Gielen, MD, PhD, is co-chair at the Department of Radiology and section anterior iliac spine, the ischial tuberosity and the iliac crest, but head of Musculoskeletal Radiology, UZA and assistent professor of Radiology at other apophyses may be aff ected as well. Both the radiologist the University of Antwerp. 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. Th e diff erential 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 competitive athletes: prevalence, location and sports distribution of 203 cases collected. Skeletal Radiol 2001;30:127-31. 2. Vanhoenacker FM, Snoeckx A, Gielen JL, Van Dyck P, Parizel PM. Imaging of muscle injuries in children and adolescents. Flemish J Sports Med Sports Sci 2005;101:39-41 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. Paul Parizel, MD, PhD, is chairman of the Department of Radiology, UZA and 5. Vandevenne JE, Vanhoenacker F, De Beuckeleer L, De Schepper AM. Chronic full professor of Radiology at the University of Antwerp. avulsive injury of the hip. JBR-BTR 2000;83:31. Address for correspondence: F.M.Vanhoenacker, Dept of Radiology, University Hospital Antwerp, UZA, University of Antwerp, Wilrijkstraat 10, B-2650 Edegem, Belgium. Tel: +32 3 821 3532, Fax +32- 3 825 2026 e-mail: fi lip. [email protected] 15 Conference report

The ITF Science & Technical Department hosted its 3rd International Congress on Tennis Science & ITF hosts Technology (TST) at Whitelands College at the Uni- versity of Roehampton in London 10-12 September successful 2007. Over 90 of the world’s leading tennis science and technology researchers were present for three TST Congress 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/

British Association of Sports and Exercise Medicine July 2008 Annual Congress Brighton, 8-10 October American College of Sports Medicine; http://www.basem.co.uk/ International Team Physician Course Santiago, 23-25 July http://www.acsm.org November 2008

International Federation of Sports Medicine; August 2008 FIMS World Congress Barcalona, 18-23 November STMS North American Regional Conference http://www.femede.es/congressbarcelona08 Cincinnati, Ohio, USA 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 balance 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. The 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. The exercises may be progressed by changing from bilateral to unilateral standing in the first drill only; 4. The exercises performed on balance boards require a combination of balancing skills and certain tennis skills (e.g. dribbling, ground strokes and volleys); 5. The 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 (sideways) 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 20

About the authors Vasiliki J. Malliou, Ph.D., 36, Makrigianni Ilioupolis, 16345, Athens, Greece Addresscorrespondence: for at the University Th of race, Dept. Science.Sports of Alexandros Mavvidis, Ph.D. is Associate Professor and Head the course tennis of University Athens, of Sports Dept Science. of Stavros Douvis, Ph.D. is Associate Professor and Head the course tennis of at the Sports Science, Komotini, in Greece at the Democritus University of Th race, Department of Physical EducationAsimenia Gioftsidou,and Ph.D. aphysical is education teacher and athletic trainer Sports Science, in Athens, Greece. onal and Kapodistrian University of Athens, Department of Physical Education & Vasiliki J. Malliou, Ph.D aphysical is education and instructor tennis at the Nati- Komotini,in Greece. critus University Th of race, Department Physical of Education and Science Sports Paraskevi Malliou, Ph.D. is is Associate Professor and athletic trainer at the Demo- 8. Askling C, Karlsson J, Th orstenssonA. Hamstringoccurrenceinjury in elite soc- 7. Kovacs M. Is static stretching for benefi tennis cial? review. A brief Sci Med 6. Silva RT, Takahashi Berra B, R, Cohen M, Matsumoto MH. Medical assistance 5. Pluim BM, Staal JB, Windler GE, Jayanthi N. Tennis injuries: occurrence, aetiol- 4. Feit EM, Berenter Lower extremity R. injuries. tennis Prevalence, etiology, and 3. Bylak J, Hutchinson Common MR. sports injuries young in players. tennis 2. Kühne CA, Zettl RP, Nast-Kolb D. [Injuries- and frequency of complaints in com- 1. Perkins RH, Davis D. Musculoskeletal injuries tennis. in Phys Med Rehabil Clin References duration that from increases 6to 14minutes (Table 1). exercise programme should eight be weeks with adaily training subconscious reaction. Th eduration of the recommended balance programme intended is to enhance coordination hand-eye and order in todrills more be sport-specifi candinteresting. e Th injuries. Th ese balance exercises shouldbe combinedwith tennis to improve proprioception and potentially reduce lower limb exercises to in their players’ daily training tennis programmes In conclusion, we recommend coaches tennis to include balance Summary: 23. Zachazewski J, Magee D, Quillen W. Athletic injuries and rehabilitation. Phila- 22. Verhagen E, Beek van der A, Twisk J, Bouter van Mechelen L,Bahr R, 21. O, Lian Bahr R, Bahr IA. A twofold reduction the in acute incidence ankle of 20. Bowden MC.Elstein R, Tennis kinetics. New York: Simon and Schuster; 1985. 19. Jerosch J, ThL, orwesten Teigelkotter T. Proprioception the shoulderof joint in 18. CH,Lin Lien YH, Wang SF, Tsauo JY. Hip and knee proprioception elite, in 17. Gioftsidou A, Malliou P. Preventing lower injuries limb soccer in players. 16. Malliou P, Gioftsidou A, Pafi sG,Beneka A, G. Godolias Proprioceptive training 15. Wedderkopp N, Kaltoft M, Lundgaard M, Rosendahl M, Froberg K. Preven- 14. Hoff manM, Payne G. e of ect proprioceptiveeff ankle disktraining on Th 13. Hewett TE, Lindenfeld JV, Riccobene JV, Noyes Th FR. e neuromus- of ect eff 12. Sherrington GS. Th e integrativeofof action the the nervous system: Review 11. Rozzi SL, Lephart SM, Sterner Kuligowski R, L.Balance training for persons 10. Fried T, Lloyd GJ. common soccer of An injuries. overview Management and 9. Caraff aA, G, Cerulli Projetti M, G,Aisa RizzoA. Prevention anterior of cruciate Sci SportsSci 2003;13(4):244-50. cer players after preseason strength training with eccentric overload. JMed Scand petitive and tennis- leisure sports]. Sportverletz Sportschaden 2004;18(2):85-9. Tennis 2006;11(2):14-16. Sport 2003;6(1):14-8. at the Brazilian juniors circuit--a tennis one-year prospective study. Med JSci ogy, and prevention. Br JSports Med 2006;40(5):415-23. mechanism. J Am Podiatr Med Assoc 1993;83(9):509-14. Sports Med 1998;26(2):119-32. N Am 2006;17(3):609-31. ing. Knee Surg Sports Traumatol Arthrosc 1996;4(1):19-21. ligament injuries soccer. in A prospective controlled proprioceptive study of train- 2004;32(6):1385-93. prevention ankle sprains: of aprospective controlled trial. Am JSports Med W. Th e of a proprioceptive ect balanceeff board trainingprogram for the tive intervention study. JMed Sports Sci 1999;9:41-7. injuries youngtion in of female players European in team handball. A prospec- delphia: W.B. Saunders Company, 1996. prospective cohort study. JMed Scand Sports Sci 1997;7(3):172-177. sprains volleyball in after the introduction prevention aninjury of program. A young players. tennis Sportverletz Sportschaden 1997;11(1):1-9. amateur, and novice players. tennis Am JPhys Med Rehabil 2006;85(3):216-21. Strength Cond J2006;28:2-5. Back Musculoskeletal Rehabil 2004;17:101-4. (balance exercises) reduces lower extremity injuries young in soccer players. J healthy subjects. JOSPT 1995;21(2):90-3. Med 1999;27:699-706. the trainingknee incidence injuriescular of females in of athletes. Am JSports Charles Scribner’s Sons, 1906. afferent neural knee system and its contribution of to motor learning. New York, with functionally unstable ankles. JOSPT 1999;29(8):478-486. prevention. Sports Med 1992;14(4):269-75. Book review

Rudolph Schabus and Elisabeth Bosina Med Sci Tennis 2008;13(2):21 The Knee: Patient evaluation / Imaging / Therapy and Rehabilitation

This book about the knee joint is a manual for physicians, physical therapists and patients. It is written in a way patients can understand, but of suffi cient medical interest to be useful to physicians such as orthopaedic surgeons and sports physicians. The book empha- sizes the interaction between the physi-

Das Knie cian, physical therapist and patient during the Diagnostik- Therapie- Rehabilitation rehabilitation process. It explains how to make Rudolph Schabus and Elisabeth Bosina Vienna: Springer Verlag 2007, Pages: 164, Price: EUR 99,95 a successful return to sport and how to prevent ISBN: 978-3-211-29686-8 www.spinger.com injuries from re-occurring.

“Th e knee” is divided into three main sections. Th e fi rst section includes general information in which the anatomy of the knee is explained and biomechanical information is provided for the diff erent knee components during movement. Th e second section of the book describes common knee injuries in detail, and explains trauma mechanism, physical examination and injury-specifi c imaging. It also outlines conservative treatment and operative treatment techniques. To help the reader understand the recommended conservative treatment and specifi c rehabilitation phases, each chapter is supplied with drawings of the suggested exercises. Th e operative University Professor Dr. Rudolf Schabus was born in Hermagor/Kärnten techniques are clarifi ed by images as well, to explain the diff erent in1954 and studied medicine in Vienna (1973-1978). He went on to specialise in About the authors phases of the operation. Schabus and Bosina particularly focus on traumatology at the University Clinic for Traumatology, Vienna (1979-1985) and the anterior cruciate ligament and gonarthrosis. Th ey also discuss received certifi cation as a sports physician in 1990. He is currently the Head of the Dept. of Traumatology and Sports Injuries in the Wiener Privatklinik. other common problems such as posterior cruciate ligament lesions, meniscal lesions, cartilage damage and patellar instability. Th e third section of the book explains the various exercises, using appropriate images, for stretching and strengthening the diff erent muscles around the knee joint. Th ere 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 physiotherapist, she went on to specialise in sports physiotherapy. From 1989, she sports physician 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 high performance tennis serve

Th e ‘why’ Shoulder injuries rank among the most prevalent and debilitat- Th e challenges along the way (establishing the methodology) ing injuries sustained by professional tennis players. Th e loads In tennis, normative data describing the key mechanical char- endured by the tissues of the shoulder during stroke produc- acteristics of selected strokes is widespread, yet the number of tion, and more particularly the serve, are commonly implicated strokes upon which these data should be based has rarely been in shoulder joint injury.1-3 Indeed, past evidence points to these documented.7-8 Consequently, verifi cation of the repeatability loads increasing along with serve velocity, as well as with varied of the tennis serve, and the minimum number of executions segment use.4 Th e aim of this thesis was to therefore quantify upon which representative observations could be made, needed how diff erent types of serves (i.e. the fl at serve and the kick serve) to be established. In some agreement with theoretical models of and how diff erent service techniques (i.e. the foot-up) aff ected performance analysis,9 reliable evaluation of the serve appeared shoulder joint loading among high performance able-bodied and to require at least three successful service trials. Determination wheelchair players. Exciting in that it represented an opportunity of appropriate methods of data treatment, including an apposite for three-dimensional (3D) stereophotogrammetry – the gold smoothing technique to best represent higher-order kinemat- standard in motion analysis – to evaluate a tennis stroke, and, ics both pre- and post-impact, saw a cubic spline interpolative challenging as the shoulder represents something of a ‘Holy Grail’ procedure used. in upper-limb biomechanics. Accurate 3D representation of segments requires at least three non-collinear markers, or points. Additional markers are required Th e ‘where’, ‘who’ and ‘how’ to defi ne points of anatomical relevance. In the upper body, esti- Th e Vicon 612 (Oxford Metrics, Oxford, UK) system at the mation of wrist and elbow movement is relatively simple as both School of Sport Science, Exercise and Health was utilised to joints can be represented by two degrees of freedom. However, track retrorefl ective markers (UWA model) placed on twelve biomechanical modelling of the shoulder is complicated by its high performance able-bodied male tennis players and two top three degrees of freedom as well as the high rotational veloci- 30 professionally ranked male wheelchair tennis players executing ties and large ranges of motion that punctuate its involvement serves of varying type (i.e. fl at serve and kick serve) and technique. in functional tasks. Further, gimbal lock (where angles become Twelve cameras, operating at 250 Hertz, minimised the prospect of ill-defi ned as axes coincide) is of real interpretive concern when marker occlusion and optimised marker reconstruction during data shoulder joint motion is determined via the Euler angle fl exion- collection. Upper limb kinetics were calculated through inverse extension, abduction-adduction and internal-external rotation dynamics, where segmental masses and moments of inertia were ZXY decomposition typically used to describe all other joint provided from the data of De Leva 5 and Clauser et al.6 motion.10 Pilot work was thus undertaken to corroborate the ISB-recommended plane of elevation, elevation and internal-external rotation decomposition,11 and its accompanying spherical reference system, as preferrable for computing more representative 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 diff erent marker/triad positions (i.e. the technical coordinate systems) and the underlying humeral bone motion.

Th e analyses Study 1: Similar shoulder joint kinetics developed dichotomous 3D racquet velocities in the high performance able-bodied fl at serve and kick serve. Where higher peak horizontal, vertical and absolute racquet velocities were generated during the fl at serve, higher lateral velocities characterised the kick serve. Th e comparable 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 specifi c front and back lower limb joint kinematics was also shown to infl uence the development of fl at 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 Loading and velocity generation in the high performance tennis serve Th e ‘where to from here’ at the University of Western Australia • Ongoing biomechanical examination to establish best marker positions and processes of shoulder joint estimation as well as most meaningful shoulder joint representation, to further enhance the calculation and interpretation of shoulder joint motion in all overhead motions. • Examination of shoulder mechanics (inclusive of electromyog- raphy) in the fl at, slice and kick serve performance of pre- and post-pubescent high performance male and female players. • Derivation of ball spin rate and axis during the high performance serve of adult and junior players. Determination of the less dynamic engagement of their lower limbs (i.e. the ARM key kinematic characteristics that help produce ball rotation. serve: fl at serves hit with minimal active ankle, knee and hip joint fl exion-extension) saw players unable to generate commensurate References pre-impact absolute racquet velocities. Interestingly, comparable 1. Chandler TJ, Kibler WB, Stracener EC, Ziegler AK, Pace B. Shoulder strength, shoulder joint kinetics were inherent to the fl at serve, irrespective power, and endurance in college tennis players. Am J Sports Med 1992;20:455-8. of the noted lower limb kinematic variation. So, with diff erential 2. McCann PD, Bigliani LU. Shoulder pain in tennis players. Sports Med absolute racquet velocities produced via similar shoulder joint 1994;17:53-64. 3. Kibler WB. Biomechanical analysis of the shoulder during tennis activities. Clin loads but divergent ‘leg drives’, other links in the ‘kinetic chain’ Sports Med 1995;14:79-85. may be more aff ected by variable lower limb involvement. 4. Elliott B, Fleisig G, Nicholls R, Escamilla R. Technique eff ects 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 segments 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 biomechanics 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. Study 3: In contrast to able-bodied serve performance, similar 11. Wu G, van der Helm FC, Veeger HE, et al. ISB recommendation on defi nitions peak pre-impact absolute racquet velocities were generated dur- 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. ing the wheelchair fl at serve and kick serve. Wheelchair serve tactics still demanded the development of higher peak pre-impact horizontal and lateral racquet velocities during the fl at serve and kick serve, respectively. Shoulder joint kinetics were consistent across wheelchair serve type, but specifi c to the individual players; likely varying with their level and severity of spinal cord injury. When expressed relative to absolute racquet velocity, both the high-performance able-bodied and wheelchair players tolerated comparable pre- and post-impact shoulder joint loading profi les such that related shoulder joint injury risk appears analogous between populations. 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 Offi cer 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 fi lled 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 About the author PhD in Biomechanics [UWA].

Address for correspondence: [email protected]

23 Original research

Tristan Barnett, Denny Meyer and Graham Pollard Med Sci Tennis 2008;13(2):24-27

Applying match Abstract A large database of tennis statistics is used to statistics to calculate player match statistics for each court surface. Analysis is carried out to determine increase serving strategies to increase performance. The serving results of the analysis could be used by players and coaches to possibly increase serving perfor- performance mance.

Introduction There is a range of published material on the use of match statistics/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 determine 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 and receiving statistics for each player on each surface. The serve, it may be better for player A to serve two first serves serving and receiving statistics averaged across all matches on than to serve a fast first serve and a slower second serve. In each surface was also calculated. Tables 1 and 2 below give these this paper we see how the merits of this potential strategy of overall averages for men and women. The results indicate that two fast serves can be assessed statistically by a player about women serve a higher percentage of 1st serves in play compared to play a specific opponent. to men for all four surfaces. However, the results indicate that men win a higher percentage of points on the first and second This paper uses a large database as provided by KAN-soft (www. serve compared to the women for all four surfaces. Overall, the oncourt.info) to calculate player match statistics for each court results indicate that men win a higher percentage of points on surface. The methods of the analysis could be used by players and serve compared to women on all four surfaces. This agrees with coaches to increase potential serving performance. the results of Barnett and Pollard.8 The difference between the percentage of wins on first serve for men and for women is OnCourt database 8.8%. The difference between the percentage of wins on second The OnCourt database provides some match statistics since the serve for men and women is 5.5%. As the former value is greater 2003 French Open. Not all the match statistics for the ATP and than the latter value, there is a suggestion or possibility that a WTA events are given. However the number of matches and fast first and fast second serve strategy is more likely to be a rea- tournaments included in the database has increased in recent 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: WinPercentage of 1st serves in play 61.9% 61.3% 60.0% 61.5% fijs = percentage of points won on first serve given that first serve is in when player i meets player j on surface s, Percentage of points won on first serve 74.1% 73.0% 71.0% 67.1% gijs = percentage of points won on second serve when player i Percentage of points won on second serve 51.8% 51.3% 50.9% 49.2% meets player j on surface s, davs represents the average percentage of points won on return of Percentage of points won on serve 65.5% 64.6% 62.5% 60.2% first serve on surface s, Percentage of points won on return on first serve 25.9% 27.0% 29.0% 32.9% eavs represents the average percentage of points won on return of second serve on surface s. Percentage of points won on return on second serve 48.2% 48.7% 49.1% 50.8%

Percentage of points won on return of serve 34.5% 35.4% 37.5% 39.8% A simple analysis can now be used to compare two serving strategies. The first strategy is where a player serves a fast serve on the Number of matches 928 304 4319 3331 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 and a second slower serve. Even if this is not always the case, it would appear to be a reasonable assumption for the following Table 2. Match statistics for women separated by court surface analysis. Using this strategy, the percentage of points won on serve is given by: Statistic Grass Carpet Hard Clay a * f + (1- a ) * gijs Percentage of 1st serves in play 63.1% 63.4% 62.1% 63.4% is ijs is

Percentage of points won on first serve 65.4% 63.1% 62.0% 59.6% The second strategy is where a player serves a fast serve on both the first and second serve. Using this strategy, the percentage of Percentage of points won on second serve 46.1% 46.4% 45.3% 43.6% points won on serve is given by: Percentage of points won on serve 58.1% 57.0% 55.5% 53.5% a * f + (1- a ) * a * f Percentage of points won on return on first serve 34.6% 36.9% 38.0% 40.4% is ijs is is ijs

Percentage of points won on return on second serve 53.9% 53.6% 54.7% 56.4% Therefore, a player should use the second strategy if

Percentage of points won on return of serve 41.9% 43.0% 44.5% 46.5% (1-ais) * ais * fijs > (1-ais) * gijs Number of matches 881 199 3432 2293 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 0.78 0.82 0.73 0.76 0.63 0.75 0.72

cis 0.56 0.43 0.59 0.55 0.57 0.53 0.59 0.58

dis 0.28 0.23 0.29 0.28 0.28 0.26 0.31 0.42

eis 0.47 0.48 0.51 0.48 0.53 0.50 0.53 0.60

fijs 0.799 0.790 0.800 0.639 0.739 0.670 0.750 0.769

gijs 0.512 0.417 0.551 0.458 0.582 0.537 0.571 0.608

ais * fijs 0.535 0.545 0.528 0.364 0.510 0.469 0.495 0.546

Matches 37 3 99 17 24 4 72 72

tistically by such a strategy, but he might gain a moderate amount from the ‘surprise’ factor in such a strategy. Similar analyses to test for signifi cance can be performed for the other surfaces. However, it is clear that two fi rst serves will not be such a good strategy for Roddick in the case of clay surfaces.

Conclusions Th e results indicate that separating player match statistics into

diff erent court surfaces can be useful (for some players against Dr. Denny Meyer is a Senior Lecturer in Statistics at the Swinburne University some other players on particular surfaces) in making decisions of Technology. She has co-authored two books and has published upward of 50 articles in refereed journals. She is an applied statistician, working in areas such as

on serving strategies. An example where one player might benefi t About the authors sport statistics, management, tourism, mineral processing, advertising, agriculture by serving two fast serves has been given. Th e method of analysis and social research. could be used by any player or coach to see whether serving performance might be enhanced during a forthcoming match. Th us, 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- Th e authors would like to thank KAN-soft for providing the burne University of Technology. He has written several published papers, given presentations at international conferences and has a PhD in tennis modelling. He database for calculating serving and receiving statistics. has appeared on many occasions in the media including SEN sports radio and 3RRR sports segment “Run Like You Stole Something”. Tristan currently works as References a gaming mathematician for Sportsbet21 Pty Ltd. 1. Gale D. Optimal strategy for serving in tennis. Mathematics Magazine 1971;44:197-9. 2. Norman JM. Dynamic programming in tennis-when to use a fast serve. J Oper Res Soc 1985;36:75-7. 3. George SL. Optimal strategy in tennis: a simple probabilistic model. Appl Stat 1973;22:97–104. 4. Gillman L. Missing more serves may win more points. Mathematics Magazine 1985;58(4):222-4. 5. Hannan EL. An analysis of diff erent serving strategies in tennis. In: Management 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 fi rst 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- fi rst 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 aff ects player performance Dr. Tristan Barnett, Faculty of Life and Social Sciences, Swinburne University of and injuries. Med Sci Tennis 2007;12(1):34-7. Technology, John St, Hawthorn, VIC 3122 Australia Website: www.swin.edu.au/sport Email: [email protected] 27 Original research

Janet A. Young Med Sci Tennis 2008;13(2):28-31 Australian Abstract Elite junior tennis players’ perceptions of the importance of mental skills were investigated in elite tennis a study commissioned by Tennis Victoria. Eight junior boys aged 13 to 17 years and seven girls juniors’ aged 12 to16 years comprising an elite training squad at Melbourne Park responded to a ques- perceptions tionnaire. Reponses to ratings of the importance of mental and physical factors, and key mental of the skills for success were recorded, together with the time devoted to mental preparation prior to important matches and explanations for match importance losses. While mental factors and skills were strongly endorsed, no gender differences were of mental found in these endorsements or in the time devoted to mental preparation. Losses in impor- skills 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

28 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 knowledge 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 development and training with children and young adolescents,4-6 the aim of this study was to examine elite tennis juniors’ perceptions of the importance of mental skills for success and, further, to examine for gender differences in these perceptions. As such, this study complements research with adult elite athletes and coaches as to their perceptions of the importance of mental skills.7-8 In these peak performance studies, a kaleidoscope of mental skills were found to be associated with success, with key skills embracing focused attention, feelings of confidence, ability ability to control one’s nerves and anxiety; (d) concentration; and, to control nerves and anxiety, commitment and dedication.8 (e) love and interest in tennis. In addition, participants reported on how much time they devoted to mental preparation before an In this exploratory investigation of elite juniors’ perceptions of the important match. The qualitative measure in the questionnaire importance of mental skills for success it was hypothesised that: consisted of asking participants to nominate reasons for their 1. Elite junior players would rate the importance of mental fac- losses in important matches. tors for success higher than the importance of physical factors and there would be no gender differences in these ratings; Procedure 2. Elite junior boys and girls would rate the same the importance After receiving informed consent from players’ parents, the inves- of key mental skills for success; tigator met with participants prior to a training session at Mel- 3. Elite junior boys and girls would devote similar time to mental bourne Park. The investigator outlined the study’s purpose and preparation prior to important matches, and, time devoted to advised participation in the study was voluntary, there was with mental preparation prior to matches would increase with a no requirement for players to identify themselves in responding player’s age; and there were no correct, or incorrect, answers. All participants 4. Elite junior players would attribute losses in important games completed the questionnaire within 20 to 30 minutes. to mental factors. Data Analysis Method To analyse the quantitative data, a number of inferential statistics Participants was conducted. Specifically, a series of seven Mann-Whitney An elite squad of eight boys aged 13 to 17 (mean 16.1) years and U-tests were conducted to examine for differences in: (a) ratings seven girls aged 12 to 16 (mean 14.8) years participated in the of importance of physical and mental factors; and, (b) ratings study. The juniors, who were the top two ranked players in their of five key mental skills by gender. An independent t-test and a age groups in the State, trained twice weekly at Melbourne Park, Pearson’s product moment correlation were also conducted to Melbourne, Australia under the guidance of the State coach. The examine for gender differences in the amount of time devoted coaching program conducted by the State coach did not include to mental factors prior to matches and the relationship between any formal mental skills training sessions. the amount of time devoted to mental preparation and age of participants respectively. Materials Participants completed a self-report instrument (questionnaire) To analyse the qualitative data, an inductive content analysis that was developed for the purposes of this study and consisted of participants’ accounts for their losses in important games of both quantitative (n = 7) and qualitative (n = 1) measures. was conducted. In a popular procedure adopted by qualitative The quantitative measures consisted of asking participants to rate researchers,10 key words, phrases or statements (referred to as the importance of the physical (e.g. fitness) and mental (mind, ‘raw data themes’) were identified in participants’ narratives. Raw thinking) aspects of tennis for success on a 5-point Likert scale9 data themes sharing explicitly similar meaning were subsequently (anchored where 1 = not important at all to 5 = extremely im- grouped into higher order (general) dimensions. In a final pro- portant). Using the same 5-point Likert scale, and adapting Wil- cedure, these general dimensions were classified as physical (e.g. liams and Krane’s8 psychological profile of a sporting champion, physical fitness), mental (e.g. motivation) or other (e.g. weather, participants were also asked to rate the importance for success of: court conditions) factors in accord with Weinberg’s1,2 descrip- (a) success of determination and commitment; (b) self-belief; (c) tions of these factors. >>

29 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 General dimension: General dimensions: Factor Mean rating: Mean rating: junior boys junior girls

junior boys junior girlseach drill • Loss / lack of concentration • Loss / lack of concentration

Physical 4.75 4.71 • Motivation problems • Lacked self-belief

Mental 4.88 4.71 • Inability to control nerves • Inability to control temper

• Lacked physical skills • Lacked physical skills A Mann-Whitney U-test revealed no significant differences in • Inappropriate tactics participants’ ratings of the importance of physical and mental factors for success (Mann-Whitney U = 59.5, p>0.05). The classification procedure on the nine general dimensions Participants’ ratings of the importance of five mental skills and listed in Table 3 revealed the majority (78%) of dimensions attributes for success are presented in Table 2. were mental factors (with the one exception of the dimension of lacked physical skills). Table 2. Mean ratings by elite juniors (by gender) of the importance of key mental skills and attributes for success* Discussion In summary, the study found that elite junior players: Mental skill Mean rating: Mean rating: 1. Considered physical and mental factors to be equally important for success, with no gender differences in these percep- and attribute junior boy junior girl tions evident; 2. Strongly endorsed the importance of key mental skills and Determination and attributes - determination and commitment, self confidence, commitment 4.75 4.86 ability to control nerves and anxiety, concentration, love and interest in tennis – with no gender differences in these percep- Self confidence 4.88 4.71 tions evident; Ability to control 3. Spent between 1-30 minutes mentally preparing prior to important matches, with no gender differences evident in the nerves and anxiety 4.50 4.57 time devoted to mental preparation by players; Concentration 4.62 4.86 4. Nominated an array of factors (e.g. choking, attack of nerves, a lack of motivation and self confidence) to explain losses in Love and interest in tennis 4.88 4.42 important matches. The majority (78%) of nominated factors were mental ones, although a lack of physical skills was a shared * adapted from Williams and Krane8 general dimension of factors across elite junior boys and girls.

A series of five Mann-Whitney U-tests revealed no significant It was an aim of the study to examine for gender differences in differences between junior boys’ and junior girls’ ratings of the elite juniors’ perceptions of mental skills, and it is noteworthy importance of each of the five skills and attributes listed in Table 2. that no gender differences were found across a number of measures. This finding suggests there may have been a comparable Mental preparation time level of maturity shared by the elite junior boys and girls in this In terms of time devoted to mental preparation before an study. It is also possible that the finding of no gender differ- important game, junior boys reported spending between 1 to 30 ences arises as a consequence of all players, as members of an minutes (mean 12.5), compared with 10 to 20 minutes (mean elite training squad, sharing a common (or similar) training and 18.9) reported by junior girls. An independent t-test revealed coaching program conducted by the State coach. no significant differences between junior boys and junior girls in terms of their mental preparation time (t (13) = -1.5, p>0.05) As such, the study’s findings suggest that elite junior players and a Pearson’s product moment correlation revealed no signifi- possessed an acute awareness of the importance of mental skills cant relationship between mental preparation time and age of and attributes for success. While this awareness of the impor- player (Pearson’s product moment = -0.16, p>0.05). tance of mental factors did not differ significantly from players’ perceptions of the importance of physical factors, a set of five

30 key mental skills and attributes were strongly endorsed and References match losses were, in the main, attributed to mental factors. Th e 1. Weinberg R. Sport psychology and tennis. In: Dosil J (ed). Th e sport psychologist’s importance attributed to mental skills by elite junior players was handbook. Chichester: John Wiley & Sons, 2006:285-301. further strengthened in the reporting by all players of a set period 2. Weinberg R. Th e mental advantage. Chicago: Leisure Press, 1988. 3. Gould D, Damarjian N, Medbery R. An examination of mental skills training in of time devoted to mentally preparing for important matches. As junior tennis coaches. Th e Sport Psychologist 1999;13:127-43. such, this study’s fi ndings are consistent with, and lend support 4. Crespo M, Cooke K. What research tells us about junior tennis. ITF Coaching to, fi ndings from studies on adult athletes and coaches’ percep- Sport Sci Rev 1999:20:17-8. tions of the importance of mental skills7 and a mental skills 5. Vealey RS. Future directions in psychological skill training. Sport Psychol 8 1988;2:318-336. profi le linked with successful performance. 6. Weiss MR. Psychological skill development in children and adolescents. Sport Psychol 1991;5:335-54. Th e implications of this study suggest it would be appropriate, 7. Orlick T, Partington J. Mental links to excellence. Th e Sport Psychologist and responsible, for coaches (qualifi ed/trained in sport psychol- 1988;1:105-30. 8. Williams JM, Krane V. Psychological characteristics of peak performance. In: ogy) to integrate mental skill training into elite juniors’ normal Williams JM (ed.). Applied sport psychology: Personal growth to peak perfor- training schedules. Mental skills training need not be deferred to mance (4th ed). Mountain View: Mayfi eld, 2001:162-178. post-junior or open coaching programs but could be introduced 9. Lehman, RS. Statistics and research design in the behavioral sciences. Belmont: at an earlier stage of development for aspiring players.1-3 Th e Wadsworth Publishing, 1991. 10. Jackson SA. Toward a conceptual understanding to the fl ow experience in elite juniors in this study (who received no formal mental skills athletes. Res Q Exerc Sport 1996;67(1):76-90. training in the State coaching program) clearly demonstrated an 11. Patton MQ. Qualitative evaluation methods (2nd ed.). Beverly Hills: Sage, 1990. awareness of the importance of mental factors and skills and had already adopted a key guideline of such a mental skills training program in setting aside specifi c time to mentally prepare for matches.

Several factors limit the validity of this study’s fi ndings including the small sample size (albeit ‘an information rich’ group of participants11) and a restricted number of questions adopted in the questionnaire. Th is study’s fi ndings suggest much could be gained in adopting a qualitative approach in future research to further explore elite junior players’ perceptions on what it takes Dr Janet A Young, B.Com., BA (Hons), PhD, MAPS, is a lecturer in the School of Human Movement, Recreation and Performance at Victoria University and also to be a champion and what suggestions they would off er for conducts a sport psychology practice based in Melbourne, Australia. Her research aspiring players to adopt to achieve excellence and enjoyment in interests include optimal performance and experiential states, talent development, mental toughness and retirement from sport. competing. Dr Young has had a long involvement in tennis both at a National and Internati- onal level in roles including Head of Women’s Tennis at Tennis Australia, Tour As an exploratory investigation of elite juniors’ perception of Director for the Women’s Tennis Association, Australian Fed Cup Manager, Tournament Director of the Richard Luton Properties Canberra Women’s Classic mental skills, this study starts to address Gould et al.3 call for and member of the ITF Women’s Pro Circuit Committee. As a former Australian more knowledge about mental skills in junior tennis. If this were representative, Dr Young was a member of two winning Fed Cup Teams. Tennis Australia and the International Hall of Fame recently honoured Dr Young a tennis match, it would be appropriate for the umpire to now for her contributions to Australian Tennis. call the score at ‘advantage researcher’, being a time ripe for a fuller About the author understanding of those elements underpinning success in junior Address for correspondence: Dr Janet Young, Sport, Recreation and Fitness, School of Sport and Science, tennis. Victoria University, PO Box 14428, Melbourne Vic 8001, Australia.

31 Dr. Gary Windler is an orthopaedic surgeon spe- Meet the cializing in sports medicine in Charleston, South Carolina. Dr. Windler is a member of the ATP Medical expert: Services Committee, and has served as a tournament physician for ATP and WTA tournaments. Dr. Gary He is a team physician for professional soccer, ice hockey, and baseball teams in Charleston as Windler well as Charleston Southern University. Long Beach, California, and a second orthopaedic clinical and research fellowship at the Nuffield and John Radcliffe Hospitals in Oxford, England. Why did you do these fellowships and what did you learn from it?

I wanted to pursue a career in sports medicine. The fellowship in Long Beach prepared me most for developing my sports medicine practice. However, Dr. Jackson was a wonderful mentor who taught me much more than just orthopaedic sports medicine. The year I spent in Oxford provided a tremendous cultural experience – my wife Rhicky and I lived with orthopaedic fellows and their families from nine different countries. I gained an awareness of the similarities and differences in how medicine is practised in countries outside of the United States.

Med Sci Tennis 2008;13(2):32-33 4. When did you first get involved in ‘tennis medicine’?

I attended a STMS meeting in Ponte Vedra Beach, Florida in the 1. What are your favourite sports and how did you mid 90s. That is when I realised there were many talented people become interested in tennis? who shared an interest in tennis medicine and science.

I played American football, basketball and lacrosse in high school and went on to play college lacrosse. I really didn’t play any ten- 5. You were an ATP Traveling Sports Medicine Fellow nis until college when I began playing recreationally. I’ve been in 2000. How did that happen and what have you hooked on it ever since. As I get older, and unfortunately a step learned from it? slower, it’s still exciting to me to learn how to hit a new shot that I couldn’t hit before. I was extremely fortunate to have been given the opportunity by Dr. David Altchek and Dr. Per Renström to step into that position. Most of the six months was spent travelling to tournaments in the 2. Why did you decide to pursue a career in orthopaedic U.S. and Europe as a representative of the ATP Medical Services. surgery? That experience helped me to better understand what the players go through on a physical and emotional level being on tour week in When we were going through our clinical rotations in medical and week out for 11 months of the year. It also provided a unique school, I found that I related best to the orthopaedic residents. insight into the challenges of providing medical care to professional Also, since I was always involved in sports, orthopaedics seemed tennis players on tour. like a natural fit for me.

6. You have been a member of the ATP Medical Ser- 3. You did a fellowship in Knee and Sports Medicine vices Committee since 2000 and are currently one of under the direction of Dr. Douglas W. Jackson in the ATP Medical Directors. What is your main task?

32 Dr Gary Windler (right) examines Max Mirnyi’s shoulder

The ATP Medical Services Committee is responsible for coordinat- ing all aspects of player medical care at ATP tournaments around the 9. Every two years, the ATP organizes a Tournament world. This can be somewhat of a daunting task. Unlike taking care Physician Conference for all the doctors working at of a sports “team”, the professional tennis “tour” functions more like a ATP Tournament. What are the goals of these meet- travelling circus. We have players from many different countries with ings and are those goals accomplished? a variety of injuries and illnesses to contend with. Fortunately, over the years, we have been able to put together a very talented group of The ATP, through its support of the Tournament Physician’s ATP Sports Medicine Trainers and Tournament Physicians to take Conference, provides the opportunity for the many dedicated on the responsibility of providing medical care at these events. people involved in providing medical care at ATP and Grand Slam tournaments to come together. The goals of the conference are to discuss tournament medical issues, present some of the 7. You have done many ‘physicals’ on ATP players with latest information in tennis medicine and science, and promote Todd Ellenbecker. What is the purpose of these collegiality and a sense of team building among the ATP Tourna- physicals and what have you learned from them? ment Physicians. We have been very pleased with the feedback we have received from participants and so I think that our goals Todd and I started doing musculoskeletal screenings on the players are being achieved. during the 2006 season. The primary aim of these screenings is to identify muscle weakness, joint and muscle inflexibilities and muscle imbalances that may contribute to an increased risk of injury. By pro- 10. You are currently involved in a joint project be- viding players with an individualised exercise programme to address tween the ATP and WTA in the development of any deficiencies that are found, we hope to be able to reduce the num- a comprehensive medical documentation system. ber and severity of injuries and perhaps improve performance as well. How do you envision this new system impacting the ATP and WTA players?

8. In which areas of tennis medicine is further research This collaborative project has been in the works for a couple of needed? years now. It has proved to be quite an undertaking. Once imple- mented, it will improve communication among the ATP Sports Unfortunately, injury prevention is an area that is poorly under- Medicine Therapists, WTA Primary Health Care Providers and stood in tennis and sports medicine in general. We hope that the Tournament Physicians. They will have access to a more com- musculoskeletal screenings we are doing will help us develop a plete medical record. This will help to improve the care that the profile of what a healthy professional tennis player looks like. By players receive at tournaments around the world. In addition, the implementing more refined screening methods, I believe that bet- system will ultimately enhance our ability to collect and analyse ter strategies for injury prevention can become a reality. meaningful injury data.

33 Original research

Geoff Pollard Med Sci Tennis 2008;13(2):34-38

Abstract What is the A player can get a high percentage of fi rst serves into court by taking a low risk on fi rst service, or best serving can get a lower percentage of fi rst serves into court (with a higher probability of winning the re- sultant point if the serve goes into court) by taking strategy? a higher risk on service. This characteristic also applies to second serves. In this paper the relationship between the risks taken (on fi rst and second serves) and the probability of winning the point is considered. Using Wimbledon Championships Men’s Singles data, it is shown that the relationship between the risk taken on a serve and the probability of winning that point (if the serve goes into court), is typically not a linear one. It appears that for most players quadratic relationships are needed to model this type of data. Finally, some practical suggestions are made as to where the server might best focus his/her attention on how to increase the probability of winning a point on service.

Introduction Th e problem outlined in this paper has been considered by several authors. Gale1 described a graphical method for identifying the best fi rst serve and the best second serve from a set of serves. Redington2 concluded that in the 1971 Wimbledon fi nal, John Newcombe would have done slightly better if he had repeated his fi rst serve instead of using a softer second serve, and that his optimal second serve would have been somewhere between the two serves he used. George3 considered a typical player with a ‘strong’ and a ‘weak’ serve, and, under very general assumptions he identi- fi ed the circumstances in which the ‘strong followed by strong’ and the ‘weak followed by weak’ service strategies are better than the usual ‘strong-weak’ strategy. He also showed that, given his assumptions, the ‘weak-strong’ option is always suboptimal. His limited data set for men’s singles supported the common practice that the ‘strong-weak’ option is typically best, and it indicated that the ‘weak-weak’ option is worst. King and Baker4 carried out the same analysis as George for a larger data set of women’s singles. For one player in their data set, the ‘weak-weak’ strategy was preferable, whilst for another the ‘strong-strong’ strategy was best, but for the remaining ten players in the analysis it appeared that the ‘strong-weak’ strategy was best. A rather similar approach to the above ‘two-service (strong/weak) problem’ was given by Han- nan5 who also proposed a (rather impractical) game theory ap- Keywords: Query, statistics, quadratic relationship, percentage, probability 34 proach. More recently, McMahon and de Mestre6 addressed this he/she serves a very ‘safe’ and slowish service often with spin and ‘two-service’ problem by analyzing 414 women’s and 444 men’s not directed to a corner of the service court, and it has a very high grand slam matches in the year 2000. They concluded that in a (assumed 1) probability of going into the service court. surprising number of matches, one or both players would have They assumed that the probability the server wins the point given benefited from a departure from the ‘strong-weak’ strategy. The the service goes into the service court, increases as the level of most common beneficial change for women was to a ‘slow-slow’ risk, x, increases, and that this relationship was linear, and given strategy, and for men it was to a ‘fast-fast’ strategy (in spite of the by P(w/i and x) = a + bx additional double faults). where a + bx was assumed to take values between 0 and 1 (for It is clear that the server in tennis is faced with challenging deci- the relevant values of x), a > 0 and b > 0. € sions. On the first serve for example the server can serve a rela- Firstly analyzing the second service, they noted that the prob- tively safe serve which has a high probability of going into court, ability the server wins the point given a second serve with risk x2 but the receiver is quite likely to be able to receive such a serve was used, is given by P2(x2) = (1− 0.1x2 )(a + bx2) satisfactorily. Alternatively, the server can elect to play a faster service aimed closer to the corners of the service area, with a higher and that the associated optimal value of x2, x2*, is given by probability of winning the point if the serve goes into court.  − r if r ≤  5 €0 .5 10 However, such a serve is more likely to be a fault. There is clearly x2* =    0 if r ≥10 a ‘balance’ between taking too small a risk and taking too large a risk on the first service. There is also such a ‘balance’ on the sec- where r =a/b. The probability that the server wins the point ond service, although the penalty for not getting the second serve given a first service with risk x1 is used and a second service with into play is typically considerable (the server loses the point).€ risk x2 is used (if required), is given by Pollard and Pollard7 considered this ‘balance’ and concluded that P1(x1,x2 ) = (1− 0.1x1)(a + bx1) + (0.1x1)(1− 0.1x2 )(a + bx2) ‘for a wide range of players, the optimal [serving] strategy is such that the first service should go into play between about 50% and and the associated optimal value of x1, x1*, is given by about 60% of the time’, and, ‘the optimal strategy for the second  − r + r 2 if r ≤  serve is such that it should go into play typically between about€ 6.25 0.25 0.0125 10 x1* =   85-90% and 100% of the time.’ Further, they concluded that ‘a  5 if r ≥10  player who often gets (say) 70% of first services into play may not be serving optimally, and possibly should aim to take greater For example, for a player who wins about 50% of points when x = risks on the first serve. Correspondingly, a player who gets €only 0 and the service goes into play, and about 80% of points when x = (say) 30% of first services into play should aim to take fewer risks 6 and the service goes into play, a = 0.5 and b = 0.05. on the first serve. Also, a player who gets almost 100% of second Thus, given a straight line relationship between the risk and the serves into play may benefit from doing a few more double faults probability of winning the point if the serve goes in, the optimal provided he/she has a sufficient increase in the probability of risk on the first serve is 5 when r is greater or equal to 10 and is winning the point when the ball goes into play.’ They also studied slightly greater than 5 when r is less than 10. Thus, the optimal risk the price paid by the server for not serving optimally. on first service can never be less than 5 when the above relationship is linear. The optimal risk on first service can however be less than In this paper the relationship between the risks taken (on first 5 when the above relationship is quadratic rather than linear. and second serves) and the probability of winning the point is The average risk taken by the players in the Wimbledon Men’s considered. Linear and quadratic relationships are considered, Singles Championships 1992-1995 on first service was 4.06.8 and it appears that for the typical male professional player a Thus, it would appear that for many men or even for most men quadratic relationship is necessary to model this situation. Finally the optimal risk on first service is less than 5, and a quadratic in this paper, some practical suggestions are made as to where the relationship can be used to model this situation. server might best focus his/her attention on how to increase the probability of winning a point on service. Using the quadratic relationship a+bx+cx2 (rather than the linear one above) for P(w/i and x), it can be shown that the optimal Methods value of x for the second serve is given by Pollard and Pollard7 assumed that the probability of a service x * = (c − 0.1b+ c 2 + 0.1bc + 0.01(b2 − 3ac) )/0.3c going into the service court, P(i), decreased as the server took 2 greater risk with his/her service. They denoted the risk by x on if this expression is positive, and zero otherwise. The associated a scale from 0 to 10, and P(i/x) was assumed to equal 1-0.1x. value of P2(x2*) is given by Thus, x=1 was used to represent the situation in which the€ server 2 P2 *(x2*) = (1− 0.1x2*)(a + bx2 *+cx2 * ) has a probability of 0.9 of putting serves into play, x=2 was used to represent the situation in which the server has a probability and the optimal value for the first service is given by of 0.8 of putting services into play,….They noted that when the 2 2 x * = (c − 0.1b+ c + 0.1bc + 0.01(b − 3ac + 3cP *(x *) /0.3c server takes maximum risk (x=10), he/she typically serves a€ very 1 2 2 fast service aimed at the corner of the service court, and it has if this expression is positive, and zero otherwise. very little (assumed zero) chance of going into the service court. The probability,P , that the server wins a point is given by Also, when the server takes minimal risk (x=0), they noted €that >> P = P1iP (w1 /i) + (1− P1i )P2iP (w2 /i)

35 € ability that the server wins the point given the second service is not a fault. For the data on the 1992-1995 Wimbledon singles in the paper by Magnus and Klaassen,8 these probabilities have estimates of 0.594, 0.733, 0.864 and 0.594 respectively for men, and 0.608, 0.622, 0.860 and 0.541 respectively for women. For these men’s singles statistics the estimated probability of winning the point on the first serve is 0.733 when the estimated risk taken is 10*(1-0.594) = 4.06, and the estimated probability of winning the point on the second serve is 0.594 when the estimated risk taken is 10*(1-0.864) = 1.36. The overall probability of winning a point is 0.644. Norton and Clarke9 added service data from men’s and women’s singles at Wimbledon 2001, the French Open 2001, the Australian Open 2000-2002 plus doubles data from Australian Open 2001 to the 1992-1995 Wimbledon data uti- lized here. They noted the ‘expected’ slight differences in service statistics between the three tournaments (surfaces).

We consider now an ‘average’ professional male tennis player with the above average statistical characteristics. Further, we assume that these five statistics (0.594, 0.733, 0.864, 0.594 and 0.644) are not far from their ‘optimal’ values for this ‘average’ player. This would appear to be a reasonable assumption as it seems unlikely that, for such an ‘average’ professional player, any one of the statistics is a long way from optimal for him. The fact that the risk taken on first service is substantially less than 5 indicates that the above linear model is inappropriate, and that a quadratic one could be appropriate. Thus, fitting the above quadratic model, the estimates of a, b and c for professional male players are (to 3 significant figures) 0.491, 0.0837 and -0.00591 respectively. This fitted quadratic relationship is shown in figure 1. For professional female players, the corresponding estimates for a, b and c are (to 3 significant figures) 0.479, 0.0487 and -0.00310 respectively. where P1i is the probability that the first service is not a fault In the remainder of this paper, for simplicity, the discussion is (i.e. is ‘in court’), P(w1/i) is the probability that the server wins presented in terms of the data for male professional players. the point given the first serve is in court,P 2i is the probability However, all of that discussion is directly relevant to female that the second service is not a fault, and P(w2/i) is the prob- professional players as well.

36 It can be concluded that, for a player with the above ‘average’ C4 in figure 2 is the curve of P( 1i, P(w1/i)) values such that the statistical characteristics, it is not possible to use a straight line player’s overall probability of winning the point is 0.677, whilst to explain the relationship between the risk taken on serve leaving P2i and P(w2/i) unchanged at 0.864 and 0.594 respec- and the probability of winning the point if the serve goes in. A tively. Also, for comparative purposes, the curve C3 is the curve quadratic expression, however, has been used above successfully. of (P1i, P(w1/i)) values such that the player’s overall probability This conclusion is not to say that a (possibly small) percentage of winning the point remains at the original 0.644, whilst leav- of players does in fact have a linear relationship rather than a ing P2i and P(w2/i) unchanged at 0.864 and 0.594 respectively. quadratic one. Each player could experiment with his serve with Thus, it can be seen that the above player can lift his probability the view to identifying the nature (linear or quadratic) of their of winning a point from 0.644 to 0.677 by lifting P1i by 0.149 own particular risk/winning relationship. Given the quality and from 0.594 to 0.743, or by lifting P2i by 0.136 from 0.864 to 1.0, sample size of the above Wimbledon data however, it would seem or by lifting P(w2/i) by 0.094 from 0.594 to 0.688, or by lifting reasonable to believe that the relationship is a quadratic one for P(w1/i) by 0.055 from 0.733 to 0.788. Thus, the above player the majority of players. with ‘average’ characteristics gets the greatest return by increasing P(w1/i) by (say) one percentage point, then the next biggest As can be seen from the previous equation, there are four options return by increasing P(w2/i) by (say) one percentage point, then for doing this. Increase P1i, P(w1/i), P2i and/or P(w2/i). One or the next biggest by increasing P2i by (say) one percentage point, two of these options may be preferable to the others. To look at and finally the smallest by increasingP 1i by (say) one percent- this, we consider the ‘average’ professional considered above. age point. Of course, it may be more difficult to increaseP( w1/i) We consider firstly, and simply as an example, the above ‘average’ by one percentage point than to increase (say) P1i by the same player improving (just) his second serve by increasing P2i from amount, but it can still be useful to know the relative sizes of the 0.864 to (say) 1.0, whilst leaving the other three probability val- various benefits achieved by such improvements in play. Thus, for ues unchanged. If this player can increase P2i from 0.864 to 1.0, the above player, increasing P(w1/i) by one percentage point has a whilst leaving the other three probabilities unchanged, his overall benefit approximately 2.7 times greater than the benefit obtained probability of winning the point increases from 0.644 to 0.677. by increasing P1i by the same amount ( note 0.149/0.0.055 = 2.7 The curve C2 in figure 2 is a curve with variousP ( 2i, P(w2/i)) approximately). Also, if the above player increased P(w1/i) by one values for the second serve such that the player’s overall probabil- percentage point and decreased P1i by one percentage point, his ity of winning the point is always 0.677, whilst leaving P1i and overall increase in the probability of winning the point would be P(w1/i) unchanged at 0.594 and 0.733 respectively. For compara- about 1.65 ( a little less than 1.7 due to a negative interaction be- tive purposes, the curve C1 in figure 2 is the curve of various tween the two actions) times the increase he would have achieved (P2i, P(w2/i)) values such that the player’s overall probability of by increasing just P1i by one percentage point. (Note that these winning the point remains constant at the original 0.644, whilst factors of 2.7 and 1.65, and the general nature of the conclusion leaving P1i and P(w1/i) unchanged at 0.594 and 0.733 respectively. here, are not sensitive to the assumption that this player is an ‘average’ player rather than any player at all.) In practice this ‘average’ We secondly consider increasing P1i whilst leaving the other player would probably try to increase more than just one of these probabilities P(w1/i), P2i and P(w2/i) unchanged at 0.733, 0.864 probabilities at a time, and in doing so try to move from a curve and 0.594, so that the overall probability of winning the point such as C1 to one such as C2 for the second serve, and/or from increases from 0.644 to the above value of 0.677. This value one such as C3 to one such as C4 for the first serve. The graphs >> of P1i is 0.743, a considerable increase from 0.594. The curve in Figure 2 indicate that, for the ‘average’ professional player, there

37 would appear to be greater scope for increasing the probability of Conclusions winning a point by focusing (initially at least) on improving the Data from the Wimbledon Men’s singles 1992-1995 Champion- fi rst serve outcome (i.e.P( w1/i), and possibly P1i simultaneously) ships indicates that for many men the relationship between the rather than on improving the second serve outcome. One aspect probability of winning the point (if the serve goes in) and the risk of there being greater scope on the fi rst serve is that there is a taken on that serve is a quadratic one rather than a linear one. greater (probability serve goes in) range for possible improve- Th is is important as it indicates that for such players it is typically ments in the fi rst serve than there is for improvements in the optimal to serve greater than 50% of fi rst serves into play, and to second serve. Another aspect (as noted above) is that there is a serve a reasonably strong second serve even if it results in (say) greater overall return on the fi rst serve (the curves C3 and C4 are 0-15% double faults. Th is is not to say that the relationship is not closer together than are the curves C1 and C2 in fi gure 2). linear for some men, and if the relationship is linear for a player, it is optimal for that player to serve only 50% or even slightly less a Discussion percentage of fi rst services into play. It would appear that for many or most professional men tennis In order to serve (close to) optimally it is useful for a player to players the relationship between the probability of winning the know (at least approximately) the shape of the above relationship point and the risk taken on the serve is a quadratic one, and that for his/her own services. Th rough experimentation and data col- it is best to serve more than 50% of fi rst serves into court. For lection this should be possible for a player. some players the relationship might be linear in the range (say) In order to improve the probability of winning a point on service, it x = 3.5 to x = 5.5, in which case it can be optimal to serve only would appear that the server might focus fi rstly on improving his/ about 50% of serves into play. Th us, a player should acquire at her fi rst serve outcome rather than his/her second serve outcome. least an approximate understanding of his/her own P(i/x) and In particular, he/she might focus attention on increasing the prob- P(w/i and x) relationships, particularly in the domain of x near ability of winning the point when the fi rst serve goes in, rather than 4 and 5 for the fi rst service, and correspondingly in the domain on increasing the probability of the fi rst serve going in. of x near 0 and 1 for the second service. Th is might be achievable over time by keeping some match statistics (even some match Acknowledgement experimentation), as well as doing some service experiments on a Th e author would like to thank Graham Pollard for early discussions practice court (possibly against an opponent). on this work, and for comments on an early draft of this paper. For a player with an underlying quadratic relationship, it can be seen that the slope of this quadratic relationship near x = 5 is important/critical for the fi rst serve, and the slope near x = 0 and x = 1 is important/critical for the second serve. As this slope near x = 5 decreases, x1* decreases, implying that the server should aim to get nearer 60% or even a higher percentage of fi rst serves References into play. Correspondingly, as the slope near x = 0.5 increases, it 1. Gale D. Optimal strategy for serving in tennis. Mathematics Magazine can be optimal to serve a higher percentage of double faults. 1971;44(4):197-199. 2. Redington F. Usurpers. J the Institute of Actuaries Students Society 1972;20:353-4. 3. George SL. Optimal strategy in tennis: a simple probabilistic model. Applied Statistics 1973;22:97-104. 4. King HA, Baker J. Statistical analysis of service and match-play strategies in tennis. Can J Appl Sports Sci 1979;4(4):298-301. 5. Hannan E L. An analysis of diff erent serving strategies in tennis. In: Management Science in Sports. Ladany SP, Machol RE, Morrison DG. Amsterdam: North- Holland Publishing Company, 1976:125-136. 6. McMahon G, de Mestre N. Tennis serving strategies. In: Proceedings of the Sixth Australian Conference on Mathematics and Computers in Sport. Cohen G, Langry T (eds). University of Technology, Sydney, 2002:177-81. 7. Pollard G, Pollard G. Optimal risk taking on fi rst and second serves. Tennis science & technology 3. S Miller, J. Capel-Davies (eds). International Tennis Federation, London, 2007:273-80.

About the author 8. Magnus JR, Klaassen FJGM. On the advantage of serving fi rst in a tennis set: four years at Wimbledon. Th e Statistician 1999;48(2):247-256. 9. Norton P, Clarke SR. Serving up some grand slam tennis statistics. In: Proceed- ings of the Sixth Australian Conference on Mathematics and Computers in Sport. Cohen G, Langtry T, (eds). University of Technology, Sydney, 2002:202-9.

Geoff Pollard is the President of Tennis Australia, Vice President of the ITF and Chairman of the Technical Commission and Rules of Tennis Committee of the ITF. Prior to being elected President of Tennis Australia in 1989, he was Senior Lecturer in Statistics, Demography and Actuarial Studies at Macquarie University, Sydney. He is now undertaking a PhD at Swinburne University of Technology, Melbourne.

Address for correspondence: Geoff Pollard, Swinburne University of Technology, School of Life and Social Sciences, Melbourne, Australia

38 DVD review

Carl Petersen and Nina Nittinger Med Sci Tennis 2008;13(2):39 Core Stability Training on DVD

Core stability is increasing in popularity as a conditioning tool for Th e DVD’s sell for $ 23.95 CAD each athletes. Th e relevance of trunk muscles for optimal performance 4 DVD set (includes Core Stability 1, 2, 3 and the Agility DVD) in tennis has been well established. Dr. Ben Kibler (Past-President for $ 80.00 CAD. of the STMS) has stated that “core stability is the ability to control Information and order forms on this Fit to Play & Perform™ DVD series the position and motion of the trunk over the pelvis and leg to allow can be found at www.citysportsphysio.com or www.mapp-coaching.com optimum production, transfer and control of force and motion to the or by contacting e-mail [email protected] terminal limbs in integrated kinetic chain activities.” Carl Petersen and Nina Nittinger have launched a series of Fit to Play™ & Perform DVDs which demonstrates innovative and practical exercises for core stability training. Th e fi rst DVD Core Stability 1 focuses on “Basework & bridging” providing versatile exercises to enhance training of the core in three dimensions (3D) and multiple planes of movement. It delivers a variety of exercises in lying, supine, prone, quadruped and seated bridge positions. Th e authors show expert utilisation of balance equipment, elastic resistance and ´physio-balls´. Carl Petersen is a Partner and Director of High Performance Training at City Th e second DVD Core Stability 2, “Lower core & leg training”, Sports & Physiotherapy Clinic’s in Vancouver. He works with athletes ranging from club level to those on the WTA / ATP tennis and World Cup ski tour. He About the authors shows how to improve 3D core stability by connecting the lower travelled fulltime with the Canadian Alpine Ski Team for 15 years. His physiothe- core and legs with functional exercises that work the muscle slings in rapy and fi tness coaching roles have given him the opportunity to work with, coach closed and partially closed kinetic chain movements. Th e extended and design training programs for Olympic Gold, World Championship Gold and World Cup medallists. Petersen has worked and lectured to physicians, therapists hip position for squatting as well as optimal recruitment, balance, and coaches on 5 continents most recently in Australia, England, Ireland, Paraguay, timing and deceleration control are also emphasized. Argentina, Turkey, Switzerland and the USA. He has published over 250 articles in a variety of publications for both the Scientifi c and lay community which have Th e third DVD Core Stability 3 , “Upper core & arm training”, is of been translated into 6 languages. He has also written or co-authored 3 books particular importance for tennis players given the high demands that including Fit to Play Tennis-High Performance Training Tips and Fit to Ski. Info their strokes place on the dominant upper limb. Th e authors present at wwww.citysportsphysio.com multiple exercises for scapular stabilisation, and deceleration of posterior shoulder muscles using practical and portable equipment.

All the DVDs have an introductory “warm-up” and fi nish with a “cool-down” section. Th ey also include information that the authors have edited from a video on “Agility, balance and coordination drills”. In my opinion these DVDs are of great value to doctors, therapists and coaches in their eff orts to optimise athletic function and reduce injury in tennis players. I would like to congratulate Carl and Nina for their original and Nina Nittinger is the founder and manager of MAPP-Coaching. Nina is a former professional tennis player who spent over six years full time on the tour. She is practical contribution to Tennis Science! a certifi ed tennis and fi tness coach of the German and Swiss Tennis Federation and she is also a mental trainer in sport psychology for professional athletes. After fi nishing her Masters in sports management she has published numerous articles Javier Maquirriain, MD, PhD and co-authored 3 books about fi tness and mental training in tennis which have received wide acclaim in the International tennis and ski community. She coaches tennis full time in Davos, Switzerland. Info at www.mapp-coaching.com

39 Conference announcement 10th STMS World Congress October 2 – 4, 2008 Tokyo, Japan Welcome to Japan! Afternoon Symposium: injury prevention On the occasion of Japan being host to the 10th World Congress Symposium: injuries of the shoulder of the Society for Tennis Medicine and Science and on behalf Symposium: medical care of the Japan Tennis Association, I would like to extend a sincere Symposium: strengthening and welcome to everyone. conditioning for tennis Tennis is one of the most popular sports in Japan. Even the Symposium: wheelchair tennis Emperor and Empress have enjoyed playing tennis since the days Debate of their youth. Tennis in Japan has a long history, and already over 100 years have passed since Japan started participating in Saturday, October 4 international tournaments, attaining many achievements during Morning Instructional lecture this time. Recently, though, it seems Japan has been left behind Symposium: injuries of the knee by Europe, the US, and other countries. The Japan Tennis As- Symposium: Injuries of the foot and ankle sociation is doing all it can to improve our players, and I think Workshop: arthroscopy of the elbow everyone is well aware of the great efforts that our young players Workshop: arthroscopy of the shoulder have made at international tournaments since the start of the Debate New Year. Moreover, the Japanese National Training Center was completed this January. Now I think we will have further oppor- Social program tunities to strengthen our players and popularize tennis. In improving players and preventing injuries, medical and Tennis playing, followed by welcome reception scientific support is crucial. So this is an opportune time for the Date: 6.00-8.00 pm, Thursday October 2 10th World Congress of the Society for Tennis Medicine and Venue: Takanawa tennis center Science to be held in Tokyo. The Japan Tennis Association offers Price: included in registration fee its warmest appreciation for those participating in this congress, which is being held in Asia for the first time. Gala dinner Autumn in Japan is a truly beautiful and breathtaking season. I Date: Friday evening, October 3 hope that along with the meetings and the AIG Japan Open, you Venue: Sheraton Miyako Hotel Tokyo will have a chance to experience some of the beauty of Japan and Price: 10.000 Yen/12.000 Yen the depth of its traditional culture. * Gala dinner is limited to 100 persons by order of application

I look forward to your participation. AIG Japan Open Tennis Date: Saturday afternoon, October 4 Masaaki Morita, President, Japan Tennis Association Venu: Ariake Colosseum Price: included in registration fee Organizing committee * Tickets are limited to 100 persons

The Organizing Committee for the 10th World Congress of STMS Hotel Accommodations Congress Organizer: Moroe Beppu Vice Congress Organizer: Kaoru Umebayashi, Yoshihiro Muraki JTB Global Marketing and Travel Inc. ( JTB GMT) has reserved Secretary-General: Takayuki Sukegawa, Shoji Ishii rooms at the following hotels for Congress participants at special Treasurer: Shigemichi Kyuno discount rates. Those persons who wish to apply for hotel res- ervation are requested to complete the application form no later Key information than September 5th, 2008 by Online. Hotel assignment will be made on a first-come, first-served basis. Deadline for abstract submission June 30, 2008 Abstract notification information July 31, 2008 Sheraton Miyako Hotel Tokyo – Adjacent to the venue Deadline for hotel accommodation August 31, 2008 Grand Prince Hotel Takawana – 10 min by taxi Deadline for early registration August 31, 2008 Hotel Princess Garden - 5 min. by free shuttle bus from Meguro Station Chair Scientific program Moroe BEPPU, MD Congress Organizer Friday, October 3 Chairman & Professor Morning Instructional lecture Department of Orthopedic Surgery Symposium: injuries of the wrist St. Marianna University School of Medicine Symposium: Injuries of the elbow Kawasaki, Japan Workshop: ultrasonography of the elbow Workshop: ultrasonography of the shoulder Congress Secretariat c/o His Brains, Inc., 1013 Otokikiyama, Tempaku-ku, Nagoya 468-0063, JAPAN Tel: +81-52-836-3511 Fax: +81-52-836-3510 E-mail:[email protected] 40