Movement speed is considered essential for success in elite tennis. The aim of the present study was to develop a model of movement speed components and quantify their ageand gender-related relevance for tennis performance. Physical testing data obtained from 1,434 nationally ranked junior squad tennis players were divided according to the age at peak height velocity (YPHV) into two age groups (pre-PHV: n=103 girls, 11.7 ± 0.6 yrs.; n=466 boys, 12.7 ± 1.0 yrs.; post-PHV: n=524 girls, 14.2 ± 1.4 yrs.; n=344 boys, 15.3 ± 1.2 yrs.). After assessing anthropometrics and maturity status, all players passed a series of standardized physical tests on an indoor hard court. All data were z-standardized, filtered and sorted by gender, maturity level, and ranking position. The structuring of the speedrelated performance parameters resulted in four factors ("Elementary Speed", "Jumping Power", "Linear Speed", and "COD Speed"), which were then confirmed by factor analysis. The correlation of these factors to the national ranking position was mostly significant but rather low, with "Linear Speed" reaching the lowest (r=0.10-0.18) and "COD Speed" the highest correlation (r=0.22-0.34). Path analytic models revealed "COD Speed" as the most important factor, which is strongly influenced by "Jumping Power" and "Linear Speed," with medium effect sizes, while "Elementary Speed" affects this factor only slightly. It can be concluded that the relationship between movement speed and junior players' tennis ranking is lower than expected. The development of "COD Speed" should be prioritized during testing, training, and talent identification, independent of age group and gender. Highlights. Performance parameters for 1,434 junior players with national rankings were analyzed and assigned to four superior factors. . The impact of the factors on the ranking position, as well as the internal causal relationships, were investigated via path analysis. . "COD Speed" was the most impactful factor for tennis performance and was strongly influenced by "Linear Speed" and "Jumping Power."

Purpose According to the official rules of the International Tennis Federation, players have to serve alternately from two different positions: the deuce (right, D) and the ad court (left, AD) side. This study aimed to compare body and ball kinematics of flat serves from both service sides. Methods In a controlled, semi-court laboratory setting, 14 elite male junior players served eight flat first serves to a target field directed to the receiver’s body from both service positions in a matched and counterbalanced order. An 8-camera-Vicon-System was used to capture the 3D-landmark trajectories. Results The mean service velocity was found to be similar on both sides (D: 151.4 ± 19.8 vs. AD: 150.5 ± 19.4 km/h), while multiple characteristics of the serve and ball kinematics differed significantly (p < .05). At starting, the front-foot angle relative to the baseline (D: 39.7±17.6° vs. AD: 31.1±17.4°) and lateral distance between the feet (D: 16.3 ± 12.9 cm vs. AD: 26.2 ± 11.9 cm) were significantly different. During the service, upper torso range of motion from maximum clockwise rotation until impact was significantly greater on the deuce court (D: 130.5 ± 19.8° vs. AD: 126.7 ± 21.1°). This was especially pronounced in foot-back technique players. Further, differences in the lateral ball impact location (D: 30.0 ± 24.1 cm vs. AD: 10.3 ± 23.3 cm) were observed. Conclusions Changing the service side affects the serve and ball kinematics in elite junior tennis players. Our results underline biomechanical differences regarding the starting position (feet and upper torso) as well as the movement and ball kinematics which could be relevant for skill acquisition, injury prevention and performance enhancement.

The ability for quick multidirectional accelerations is crucial for athletic performance in team and racquet sports. So far, there has been little research dedicated to different initial step patterns usually applied by players. Therefore, the present study investigated the kinematic characteristics and effectiveness of the following step patterns: Jab Step (JS), Pivot Step (PS), Gravity Step (GS) and Counter Step (CS). Twenty-two male competitive team and racquet sport athletes completed maximum lateral accelerations utilizing the step patterns. Following familiarization with each step pattern, three 5 m sprints (5 m STs) into both directions (left & right) were completed. Sprint times, the translation of the center of mass (CoM) and joint angles were obtained using three-dimensional motion analysis. 5 m STs of the CS were faster compared to the GS and PS for both directions. A detailed distance-time analysis revealed that for shorter distances only the JS was faster than the GS. Regarding the sequence in which the maximum angular velocities (max. w → $\vec{w}$ ) in the hip, the knee, and the ankle were reached during the push off, there was a proximal-to-distal sequence for the JS and the CS, but a distal-to proximal sequence for the GS and the PS. The results reveal that the JS and the CS are superior for accelerations towards the lateral direction. Specifically, they indicate that the JS is more suitable for covering very short distances and the CS is superior for covering further distances. In addition, the distal-to-proximal sequence of max. w → $\vec{w}$ during the push-off in the GS and the PS might indicate lower kinematic efficiency.

PurposeThis study aimed to correlate sprint mechanical parameters (SMP) of a linear sprint (LS) and a tennis specific modified 505 (Tm505) change of direction (CoD) test obtained with a motorized resistance device (MRD) to the current tennis ranking position (RP).Methods107 male and 86 female elite junior tennis players nationally ranked in the German Tennis Federation between 10 and 18 years participated in the study. According to their age at peak height velocity (PHV), players were divided into pre-PHV, circa-PHV, and post-PHV groups. SMP were derived from instantaneous time-velocity data of two 20 m all-out LS measured with 333 Hz. Further, mean values from two Tm505 trials with constant 3 kg loading over acceleration-deceleration (1a) and reacceleration (1b) phases were measured with an MRD. SMP of LS and CoD measurements were partially correlated with the current RP in the overall national ranking by controlling for biological maturation.ResultsLow to moderate correlations (rs = −0.1 to −0.3) were found between SMP and the RP in all male and female age groups. Correlations of the CoD measurements were overall more pronounced, particularly in girls (rs = −0.44). All linear SMP, like maximal theoretical force (F0; N/kg), and maximal theoretical velocity (v0; m/s), maximal power (Pmax; W/kg), improved over maturation for both genders with Pmax being most important for sprint performance. Further, Pmax was shown to correlate with the girls ranking position (rs = −0.31). During the Tm505, matured players achieved significantly faster overall total and CoD times. Positioning of CoM before CoD enlarged over maturation and was found to correlate to the RP in both sexes. In addition, nearly all SMP significantly correlated to the primary performance outcomes in the Tm505 test in both genders (r = −0.3 to −0.6).ConclusionCoD performance has a moderate and higher impact on tennis performance compared to LS. CoD performance as well as Pmax achieved a higher relevance for the ranking position predominantly in girls compared to boys. Hence, particularly Pmax as well as the transfer to on-court CoD motor skills should be a central training goal in elite junior tennis players besides technical skills and should depend on maturation status and gender.

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This study examined the effects of combined change of direction (CoD) and plyometric training on sand in basketball players’ jump, sprint, and CoD performances. In total, twenty-five male professional basketball players (age, 24.1 ± 4.2 years; height, 192.5 ± 8.0 cm; body mass, 92.6 ± 11.6 kg) participated in a pre-season intervention study over seven weeks, where two teams completed an identical speed training protocol, either on sand or on a hard surface, while a third team served as the control. All participants followed their regular pre-season training, while the intervention groups additionally performed the training protocol twice weekly. A repeated-measures ANOVA (rANOVA) showed significant interaction effects on the countermovement jump (F = 14.90, p < 0.001), pivot–step–jump test (F = 8.09, p = 0.002), 10 m sprint time (ST) (F = 4.18, p = 0.050), and 20 m ST (F = 8.49, p = 0.002). Moreover, an rANOVA showed significant interaction effects for the CoD performance regarding total time (F = 5.70, p = 0.010) and average velocity prior to the CoD (F = 8.40, p = 0.002) and after the CoD (F = 3.89, p = 0.036). As such, the findings suggest that sand-based training elicits kinematic adaptations, increased muscle activation, and a shift towards concentric force development that all contribute to enhanced athletic capabilities.