Background: The purpose of the study was to examine whether neuromuscular fitness contributes significantly to the success of eAlite junior tennis players of differing ages and sexes. Methods: The 160 participants, who were elite Hungarian junior tennis players (aged 11–17), were separated into four groups within this study, and 10 different types of field tests were used. Results: A moderate significant correlation was found between the results of the 5 m run (r = −0.42; r = −0.45), standing long jump (r = 0.39; r = 0.56), overhand ball throw (r = 0.44; r = 0.53), serve (r = 0.39; r = 0.64), amount of push-ups in 30 seconds (r = 0.32; r = 0.48), 10 × 5 m run in a shuttle run (r = −0.34; r = −0.45), the spider run (r = −0.34; r = −0.52), and competitive tennis success among U14 and U18 girls. A significant correlation between the overhead medicine ball throw test value (r = 0.47) and the current competitive performance was found only among U18 elite female tennis players. In contrast, no correlation was found between the values of the U14 and U18 male tennis players and their current competitive performance. Conclusions: Additional studies are needed to identify interventions that can increase sport-specific neuromuscular fitness with the ultimate goal of achieving better performance.

The aim of the present research was to test the hypothesis that rate of force development (RFD) during a handgrip task of the dominant arm in three different positions is associated with maximal post-impact ball speed of flat serve (PIBS). Altogether 23 elite junior boys (aged 14.84 ± 2.47 years; weight 59.51 ± 13.83 kg; height 170.47 ± 16.34 cm) tennis players participated in the study. To assess the maximal voluntary contraction (MVC) and RFD during the task, four handgrip tests and a serve test were applied to estimate PIBS. Spearman’s rank correlation showed a significant positive correlation between RFD of dominant arm in each three position and PIBS (r = 0.82–0.86; p < 0.001). A very large, significantly positive correlation was also found between MVC of the dominant arm and PIBS (r = 0.88; p < 0.01). The result of the present study indicated that rapid force generation of muscles in the forearm and wrist may probably play a role in the formation of a stable contact point, and it is in connection with PIBS. It is in contrast to the slow maximal force exertion that much rather characterizes the general strength state of players. Therefore, measurement of the RFD during a handgrip task is suggested in the testing session of the flat serve of junior tennis players.

Introduction: Coaches should be able to estimate successfully different physical attributes of junior tennis player’s performance such as power, in order to monitor players’ progress and to design the most appropriate training program. However, this process requires reliable and valid field tests. Objective: Aim of this study was to examine absolute and relative reliability of overhand ball throw (OBT) test within testing session and to investigate its validity. Methods: 257 Hungarian junior boy and girl tennis players (aged 11-17) separated into four groups, performed OBT and serve speed (SS) tests of standardised protocol. Results: Dependent sample t-test revealed no significant (p= 0.31-57>0.05) difference between test and retest sample means within testing session and magnitude of effect size (dz=0.1-0.5) were trivial for all groups. Furthermore, all groups had low typical percentage error (CV= 3-4 %), and standard error of measurement values was consistently low (SEM= 0.12-0.18). Within test-retest consistency illustrated strong relative reliability (ICC= 0.98-0.99). Moreover, significantly large to very large positive correlations were found between OBT and SS (r= 0.57-0.81; p˂0.01) tests. The coefficient of determination indicated that OBT explained 32-65% of the SS for groups. Conclusions: These findings suggest that absolute and relative reliability of OBT test is high within testing session and validity of OBT test is acceptable for measuring power ability of flat serve execution in junior tennis players.

Introduction: Extremely complex factors lie behind sport performance in tennis. In order to evaluate the importance and weight of these factors, it is important to examine them each by each. Objective: The aim of the research was to examine the performance-structures lying behind the physical performance of elite junior boy tennis players and to analyse the relationship between the calendar year and physical variables. Method: Altogether 80 elite junior boy tennis players participated in the research. Their average age was 14.30+2.22 years. Eleven different field tests were applied. Results: Correlations were found between the calendar year age and all the physical variables, the 5-meter linear run and the agility, the explosive strength of the leg, the 5-meter sprint and the agility. The speed of serve showed correlation with the dominant-side upper limb, the upper body and the explosive strength of the leg. Furthermore, there was a correlation between the shoulder flexibility and the flexibility of the lower limb, the flexibility of the lower leg, the explosive strength of the leg and the agility, the flexibility of the shoulder and the speed of serve. Conclusions: A differentiation in the conditioning training of elite junior boy tennis players is recommended based on their age, from the age of 11, together with the joint developmental trainings of explosive strength and flexibility, agility and explosive strength of the leg, the improving of explosive strength in the lower and upper limbs, and the use of 5 meter linear run and the athletic throws as a means of training.

The aim of our pilot study was to investigate the effects of offensive and defensive strategy conditions on external and internal training load factors in male tennis players. This study included six elite junior male tennis players (chronological age: 15.7 ± 1.0; body height: 180.7 ± 6.5 cm; body mass: 71.0 ± 10.8 kg) who had to play two simulated matches. Among the external training load variables, running activities were measured with a GPS sensor operating at 10 Hz and a 100 Hz tri-axial piezoelectric linear accelerometer integrated into it; furthermore, tennis shot activities were measured with a tennis racket-mounted smart sensor. Internal training load was measured subjectively using the RPE method. The results show that players scored significantly higher on the PlayerLoad (p = 0.031; r = 0.90) and IMA CoD low right (p = 0.031; r = 0.90) running variables and on the forehand spin (p = 0.031; r = 0.90) and backhand spin (p = 0.031; r = 0.90) when using a defensive strategy. There were no significant differences between the two strategy conditions in all other external and internal training load parameters. The defensive strategy has more acceleration in all three planes of motion, suggesting that conditioning training should be placed in the intermittent endurance capacities for players who predominantly use this strategy.

Introduction: The more precise observation of tennis players is essential to reach the best competitive performance in junior level as well. Objective: The aim of the research was to test the hypothesis that the majority of elite junior tennis players are right-handed and most of them use the two-handed backhand stroke and modern forehand and backhand grips. Furthermore the technical characteristics of the rackets used well reflect the differences in gender. Method: 40 elite male (15.92 age) and 40 elite female (16.34 age) tennis players participated in our research. Testing was carried out with calibrated means and equipment based on standard protocols. Results: 92.5% of the males and 95% of the females are right-handed. 65% of the females and 72.5% of the males use the modern semi-western forehand grip. As far as backhand groundstrokes are concerned, the frequency of the two-handed backhand stroke is 95% for females and 80% for males. 40% of the males and females used the modern two-handed backhand grip. The males used a significantly longer and heavier racket of greater swing weight than the females (p<0.05). On the other hand, females tennis players used a significantly bigger head size with a stiffer and wider frame racket than the males (p<0.05). Conclusions: The results draw attention to that the dominant arm, grips, backhand type and used rackets’ characteristic give useful information for the trends in the preparation of the elite junior tennis players.