The performance preconditions of Czech world junior tennis champions, 14 years and under, girls

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1 The performance preconditions of Czech world junior tennis champions, 14 years and under, girls Jiri Zhanel 1, Frantisek Vaverka 1, Frantisek Zlesak 1 and Piotr Unierzyski 2 1 Faculty of Physical Culture, Palacky University, Olomouc, Czech Republic 2 University School of Physical Education, Tennis Department, Poznan, Poland The report summarizes the results of a three-year longitudinal study of two prominent Czech female junior players: world junior champions in the 14 and under age group. The levels of somatic, conditioning, and coordination performance preconditions were examined using the TENDIAG1 test battery. The intra and inter-individual appraisal of results among individual players over time using mathematical-statistical methods has shown that successful tennis players typically reach an above average level in both total test battery results and in individual tests. The players studied surpass other players, notably in coordination factors (hand reaction speed, and especially leg reaction speed, as well as body flexibility), and partly in shoulder joint flexibility; members of the Czech tennis team also exhibited a high, above average level of action speed. INTRODUCTION The following report deals with the evaluation of the somatic, conditioning, and coordination performance precondition levels of two Czech girls world junior champions in the 14 and under age group from the year 2001, and points toward the possibility of practical applications of the longitudinal test results. The regular tracking of athletes performance precondition levels is an integral part of the training process. Without the continuous diagnosis, evaluation, and interpretation of results, and without the application of these results in the sport training process, it is difficult to realize the optimal and effective direction and regulation of the athlete s training program. Diversified diagnostic methods, encompassing individual factors of athletic performance in tennis, enable the formulation, when possible, of a complex model of the level of tracked performance preconditions. Diagnostic tools frequently used are motor tests and test batteries, which enable the management of conditioning, coordination capabilities, and somatic precondition levels. In previous reports (Zhanel, Vaverka, & Cernosek, 2000; Zhanel & Kadlcikova, 2001; Zhanel, Balas, Trcka & Shejbal, 2000) we presented a summary of test batteries used for performance precondition diagnostics in tennis, at home and abroad. At the same time, we drew attention to the application of the principles of so-called sport-specific tests, which were consistently derived from the analysis of athletic performance in tennis. Athletic performance factors can be divided into factors limiting performance and factors influencing performance (Tennis-Lehrplan, 1996). The limiting factors are considered to be very important, and difficult to compensate; if their level is low, the tennis player is faced with a difficult performance barrier to overcome. On the other hand, performance influencing factors are likewise important, but to a certain degree can be compensated by other strengths. Coordination and several fitness capabilities (action speed, explosive strength) are considered to be factors limiting athletic performance in tennis; physical factors (for example, height and weight) are, like several conditioning factors (endurance and strength), considered to be performance influencing factors. In the context of world tennis development, heading constantly in the direction of tennis that is more aggressive,

2 powerful, faster, and demands higher level of overall physical conditioning, arises the significance of regular and long term (longitudinal) tracking of the level of conditioning-coordination performance preconditions. The use of mathematic-statistical methods over time enables the tracking of trend development within the performance preconditions followed, and the analysis of the strengths and weaknesses of individual players. With the goal of assessing the structures of athletic performance in tennis, this analysis indicates the significance of individual factors. Within the framework of the project Czech Tennis Into The Next Millennium there is, with the support of the Czech Tennis Association, a regular analysis of the performance preconditions of members of representation teams and tennis centers using the TENDIAG1 test battery, which analyzes the somatic, conditioning, and coordination preconditions (Table 1). TEST BATTERY TENDIAG1 I. PHYSICAL PRECONDITION FIELD Body height (cm) Body weight (kg) Shoulder joint flexibility (index) II. CONDITIONING FIELD Racket hand grip strength (kp) Speed - running speed with direction change(sec.) Endurance - shuttle run short term endurance(sec.) III. COORDINATION FIELD Hand reaction speed - to visual stimulus (sec.) Leg reaction speed - to visual stimulus (sec.) Body flexibility (num.) Table 1. Test battery for the diagnosis of performance preconditions in tennis (TENDIAG1) In a subsequent part of this report we will present the results of a longitudinal study of two prominent Czech female junior players, with the goal of comparing the levels of individual performance preconditions among these players, as well as with the average values of a group of similar age Czech female tennis players (CFTP). METHOD Starting in the year 1998, using the test battery TENDIAG1 for the analysis of performance preconditions in tennis (Zhanel, Balas, Trcka & Schejbal, 2000), approximately 250 male and 300 female tennis players of various ages (9 to 24) and various performance levels (club players, members of representation teams) were tested. A tri-level performance norm enables the performance evaluation of the tested individuals using an individual test profile in graphic and numerical form (using the TENPROG computer program). In addition to actual information concerning the performance levels of individual players, it is possible, with regular and repeated testing, to follow their long term (longitudinal) development.

3 The test battery outputs are: 1. An individual test profile of the athlete enabling the evaluation of results of individual tests on the tri-level scale using the values below-average, average, above-average in numerical and graphic forms. The total test battery result is the compilation of points from the individual test evaluations. 2. The longitudinal evaluation of the performance precondition levels of the athletes in the form of a time schedule showing information about the development of trends of the individual factors. Characteristics of Czech female juniors players in the 14 and under age group at the 2001 World Championships: LS (born in 1987, team player #1): #1 player in the Czech rankings u.14 in 2001, member of team which took second place at the European Championships, 14 years and under, member of team which won the World Championships, 14 years and under; third place in doubles at the European Championships, 14 years and under; member of team that took second place at 2000 European and World Championships, 14 years and under; runner-up in doubles at European Championships, 14 years and under; member of team that won 1999 European Championships, 14 years and under. RK (born in 1987, #2 team player): 3 rd place in 2001 Czech rankings u.14, member of team that took second place at European Championships, 14 years and under, member of team that won World Championships, 14 years and under; runner-up in doubles at European Championships, 14 years and under. The testing of LS and RK was performed in the course of the years in six terms, six months apart. Both players were regularly tested in nearly identical ages between 11 and 14 (Table 1). In the interest of eliminating the intra-individual variation of results and to highlight trend developments we used the method of sliding average in eight cases in order to smooth out the time sequences. RESULTS AND DISCUSSION An intra and inter-individual comparison, one that compares both an individual s various test results over time and compares the results of a number of players to each other, with a control group of players (n=250), is presented in graphic form in pictures 1,2, and 3. The results of the long-term tracking of players LS and RK using the TENDIAG1 test battery is summarized in table 2. The test result analysis of the somatic, conditioning, and coordination performance preconditions led us to the following evaluations: Somatic indicators The longitudinal tracking of somatic indicators (fig. 1) showed, in both players, relatively small deviations in body height and weight in relation to the test group: player LS was at first slightly below average body height, from the age of 13 she was subsequently slightly above average body height. During the entire test period her body weight was below the test group average. During the entire test period player RK was slightly below the test group average in both body height and weight. In the indicator shoulder joint flexibility player LS achieved a highly above average level; in the second half of the test period the flexibility levels of the two players became equal and was mostly significantly above average (with the exception of the apparently random drop during test #4).

4 TENDIAG1 Tests Name Age (years) LS RK Height (cm) LS ,5 169,5 RK ,5 163 Weight (kg) LS , RK ,5 Shoulder joint flexibility LS RK Grip strength** (kp) LS RK Speed (sec.) LS RK Endurance (sec.) LS RK Hand reaction speed (sec.) LS RK Leg reaction speed (sec.) LS RK Body flexibility (num.) LS RK Test battery score LS RK Table 2. TENDIAG1 test battery entries and individual values of tested players Legend: * test not performed; racket hand Conditioning indicators The analysis of the conditioning indicator levels (fig. 2) show that the results of the racket-hand grip strength in both players were near the test group average (player RK showed a slightly stronger grip); player LS showed a highly above average speed, while player RK showed speed indicator values around average for the test period. Both players showed a long-term, above average endurance level (player RK with a sliding trend, both players falling slightly at the end of the test period); RK showed a better over-all endurance level during the test period. The total falling trend of the endurance level corresponds with that in the normal population and is even confirmed, somewhat surprisingly, in the case of world class athletes.

5 sec. Sec. kp sec. Index cm kg 175 BODY HEIGHT BODY WEIGHT SHOULDER JOINT FLEXIBILITY Figure 1. Somatic indicators Legend: CFTP LS RK RACKET HAND GRIP STRENGTH ENDURANCE Figure 2. Conditioning indicators SPEED Legend: CFTP LS RK RK (trend)

6 num. sec. sec. Coordination indicators The tracking of coordination indicator levels (fig. 3) shows that the results of player LS in all three indicators were the entire time above the test group average and predominantly above the levels of player RK. The results of both players in the hand reaction speed tests were above the levels of the test group for the long term (significantly at the beginning); while player RK showed continual improvement in this test, player LS showed, from the beginning, stabilized high-level results. Likewise, both players showed long term, above average results in the test for leg reaction speed, which player LS maintained for the entire test period; player RK showed significant improvement in the final two tests. In the test for body mobility player LS achieved long term above average results; player RK showed results around the test group average HAND REACTION SPEED LEG REACTION SPEED 55 BODY FLEXIBILITY Legend: CFTP LS RK LS (trend) RK (trend) 30 CONCLUSION Figure 3. Coordination indicators The total points earned by the players in the test battery (last two rows in table 1) signal stabile and high conditioning-coordination performance precondition levels in player LS, while player RK exhibits fluctuations in her total performance precondition levels. With regard to player LS s higher level of tennis performance it is possible to state, on the basis of the comparisons, that her notable strengths are action speed, hand reaction speed, and especially leg reaction speed and body flexibility. Regarding the achievement of the maximum possible total points in the test battery (12 points), the totals of both players typically run high above the average level (6 points). This indicates that the players followed in this study are above average in their conditioning and coordination preparation, and that this is an indispensable basis for reaching a high level of tennis performance.

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