Determinant Physical Factors of Tennis Serve Velocity: A Brief Review

Structural and Functional Changes of the Heart in Young Adult Tennis Players

ABSTRACT

This cross-sectional observational study investigated undetermined cardiac remodeling and functional adaptation in young tennis players. Fourteen males with regular tennis training (at least three times a week, mean playing age 8.3 ± 3.8 years, tennis group, tennis) and 12 males without any racket sports engagement (the control group, [CTL]) underwent comprehensive cardiac measurements using real-time three-dimensional echocardiography, recording of baseline characteristics, blood tests, and estimation of VO 2 max by 12-min running. Data were analyzed to compare the two groups. Two groups were of similar age (mean age, CTL 20.9 ± 2.4 vs. tennis 22.5 ± 4.4 years, P = 0.235) and with similar body size. Compared with the CTL, Tennis group had slower pulse rate (70.9 ± 7.0/min vs. CTL 85.5 ± 9.6/min, P < 0.001), greater VO 2 max (43.4 ± 3.8 mL/Kg/min vs. CTL 33.1 ± 4.8 mL/Kg/min, P < 0.001), but similar blood levels of hematocrit, NT-pro-brain natriuretic peptide, and creatinine phosphokinase. The tennis group had greater left ventricle posterior wall thickness (0.90 ± 0.06 cm vs. CTL 0.81 ± 0.10 cm, P < 0.001), greater right ventricle (RV) volume index (77.8 ± 9.6 mL vs. CTL 64.9 ± 10.1 mL, P = 0.003), and greater left atrial volume index (26.9 ± 5.5 mL/m 2 vs. CTL 21.9 ± 2.7 mL/m 2 , P = 0.006). The tennis group had significantly increased RV strain (free wall strain, -26.5 ± 3.7% vs. CTL -23.3 ±2.8%, P = 0.025). However, the global longitudinal strains in the left atrium and left ventricle were similar between the two groups. Cardiac remodeling in young tennis players includes right ventricular dilatation with enhanced dynamic function, an enlarged left atrium with well-preserved function, and a predominant posterior wall thickening of the left ventricle.

Changes in shoulder range of motion and muscle strength, and upper limb performance immediately after participation in throwing and racket sports: A systematic review and meta-analysis

Objective

To systematically review studies investigating alterations in shoulder range of motion (ROM), muscle strength, and upper limb performance immediately following participation in throwing or racket sports.

Methods

The search was conducted in MEDLINE via Ovid, EMBASE, CINAHL, SPORTDiscus, Cochrane Central Register for Controlled Trials (CENTRAL), Web of Science, and Scopus databases. Studies assessing changes in shoulder ROM, muscle strength, and upper limb performance immediately after exposure to throwing or racket sports were selected. The Quality Assessment Tool for Before-After Studies (NIH) was used to quantify the risk of bias. Meta-analyses were conducted to verify clinical changes in the selected outcomes.

Results

A total of 9149 records were identified, and 27 were included in the meta-analysis. There was a decrease in internal rotation (IR) ROM of the shoulder (SMD: 0.50; 95% confidence interval [CI]: 0.22, 0.79) and throwing speed (SMD: 0.42; 95% CI: 0.15, 0.70) immediately after participation in throwing sports, while no significant changes were observed in racket sports.

Conclusion

Exposure to real or simulated matches reduced IR ROM and ball speed in throwers but not in racket sports athletes. These results will assist clinicians in planning strategies to mitigate the decreases in sports performance in these athletes between matches.

Single-session upper limb plyometric training is as effective as two sessions for improving muscle strength, power, and serve velocity in male youth tennis players: a randomized parallel controlled study

Introduction

Providing a balanced training stimulus that promotes positive adaptations without excessively increasing training volume-and thereby avoiding disruptions to the training process-is a challenging task for strength and conditioning coaches. This study aimed to compare the effects of one vs. two weekly sessions of upper limb plyometric training (ULPT) on muscle strength, power, and serve velocity in male youth tennis players.

Methods

We conducted a randomized controlled study with two ULPT groups: one receiving one session weekly (ULPT1w) and the other two sessions (ULPT2w), alongside a control group maintaining regular tennis training. The intervention lasted 8 weeks. A total of 47 male youth tennis players (15.6 ± 0.9 years), competing at the trained/developmental level, participated in the study. Evaluations were conducted twice-once before the intervention and once after-assessing isometric shoulder rotation strength (internal [ISRT] and external [ESRT]) with a dynamometer, the medicine ball chest throw (MBCT), seated shot-put test (SST), and serve velocity using a radar gun.

Results

In the post-intervention, significant differences were observed between groups for the variables of ISRT (p = 0.010;η p 2  = 0.189), ESRT (p = 0.004;η p 2  = 0.226), MBCT (p = 0.012;η p 2  = 0.181), SST (p = 0.019;η p 2  = 0.164), and tennis serve velocity (p = 0.004;η p 2  = 0.226).

Conclusion

The study found that ULPT significantly improves upper limb muscle strength, power, and serve velocity in young male tennis players, with both once and twice weekly training yielding similar benefits. As practical implications coaches can effectively incorporate ULPT once a week to enhance physical performance in young male tennis players.

The effects of strength and conditioning interventions on serve speed in tennis players: a systematic review and meta-analysis

Background

Tennis performance is highly influenced by serve speed. This review aimed to evaluate and quantitatively compare the efficacy of popular strength and conditioning (S&C) training methods in enhancing the speed of the ball in the serves of tennis players.

Methods

Following PRISMA guidelines, a systematic search was conducted in the Scopus, Web of Science, SportsDiscuss, and PubMed databases without date constraints, up to July 2024. Studies included in this meta-analysis met PICOS criteria: a) randomized controlled trials with healthy tennis players, b) isolated or combined S&C training programs, c) evaluation of tennis serve speed, and d) adequate data to compute effect sizes (ESs). The PEDro scale was used to assess methodological quality.

Results

Out of 271 identified papers, 16 studies of moderate to high quality were included in the meta-analysis. Resistance training demonstrated a small but significant effect on serve speed (ES = 0.53; p < 0.001), while multimodal training exhibited a moderate and significant effect (ES = 0.79; p = 0.001). However, core training did not have a significant effect on serve speed (ES = 0.32, p = 0.231).

Conclusion

The findings suggested that S&C interventions, including resistance and multimodal training, were beneficial for increasing serve speed in tennis players. Further high-quality research is recommended to confirm this conclusion.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_ record.php?RecordID=519790, identifier CRD42024519790.

Reliability of an Inertial Measurement System Applied to the Technical Assessment of Forehand and Serve in Amateur Tennis Players

Traditional methods for evaluating tennis technique, such as visual observation and video analysis, are often subjective and time consuming. On the other hand, a quick and accurate assessment can provide immediate feedback to players and contribute to technical development, particularly in less experienced athletes. This study aims to validate the use of a single inertial measurement system to assess some relevant technical parameters of amateur players. Among other things, we attempt to search for significant correlations between the flexion extension and torsion of the torso and the lateral distance of the ball from the body at the instant of impact. This research involved a group of amateur players who performed a series of standardized gestures (forehands and serves) wearing a sensorized chest strap fitted with a wireless inertial unit. The collected data were processed to extract performance metrics. The percentage coefficient of variation for repeated measurements, Wilcoxon signed-rank test, and Spearman's correlation were used to determine the system's reliability. High reliability was found between sets of measurements in all of the investigated parameters. The statistical analysis showed moderate and strong correlations, suggesting possible applications in assessing and optimizing specific aspects of the technique, like the player's distance to the ball in the forehand or the toss in the serve. The significant variations in technical execution among the subjects emphasized the need for tailored interventions through personalized feedback. Furthermore, the system allows for the highlighting of specific areas where intervention can be achieved in order to improve gesture execution. These results prompt us to consider this system's effectiveness in developing an on-court mobile application.

Analysing tie-break performance of professional tennis players at Grand Slam matches

A tiebreak in tennis is one of the critical moments where players are expected to excel under mental pressure and maintain high level of performance. Despite the importance of tiebreak points, research exploring the performance of male and female players during such match phrase remains limited. This study aimed to investigate i) the overall tiebreak performance of male and female players in relation to the outcome, ii) to examine their point-level performance by considering different contextual variables. A total of 535 tiebreaks comprising 6380 points from the 2016-2021 US Open men's and women's singles matches were collected. The difference in match performance between winning and losing players within the entire tiebreak game was explored. A subsequent decision tree analysis was then used to analyse the effect of the contextual and performance variables on tiebreak point-by-point outcome. The results showed that male and female Winning players outperformed the Losing players in 1st Serve, Serve Width and Net approach performance. The analysis of point-level performance showed that Net point, Score scene, and Point server substantially impacted tennis players' tiebreak outcome. These findings provide valuable insight for coaches and players, informing tiebreak tactics tailoring and training in relevance to different match status.

Epidemiology and Factors Influencing Davis Cup Retirements Over the Past Twenty Years

Background

The demands of professional tennis, including physical and psychological aspects, contribute to the frequency of retirements at elite levels of the sport.

Purpose

The aim of this study was to explore the frequency of injuries and the factors that influence the retirements of professional tennis players competing in the Davis Cup over the last two decades.

Study Design

Retrospective cohort study.

Methods

The data set includes data from 6,060 men's singles matches that included 1,814,141 games from Davis Cup ties played between 2000 to 2019. Factors that might influence the retirements were studied by means of generalized linear models using Poisson distribution. Incidence rates by 1000 games and incidence rate ratios of retirements are provided as association measures.

Results

The retirement incidence was 1.05 per 1000 games [95% CI: 0.90, 1.21]. The main risk factors associated with retirements were matches played on hard courts (IRR: 2.52 [95% CI: 1.32, 4.83]) and matches played in the final two matches of the tie and in a best-of-5-set format (IRR: 2.63 [95% CI: 1.69, 4.09] and IRR: 5.52 [95% CI: 3.50, 8.69], respectively). The most common injuries that led to retirements were those affecting the lower extremities, specifically involving muscular or tendinous tissues.

Conclusion

This study provides valuable insights for coaches, players, support teams, and epidemiologists regarding retirements and their associated risk factors in Davis Cup tournaments. These findings may guide future research and inform strategies aimed at managing player health and performance in professional tennis.

Level of evidence

Level 2b.

Kinematic differences between female national and provincial athletes in the tennis serve

Background

Tennis, the second-largest ball game in the world, has a particularly wide audience. To date, little research has been conducted on the biomechanics of female serves.

Purpose

The purpose of this study was to capture the key moments by using 1,000 frames/s high-speed video analysis, to analyze the kinematics of the serving techniques of national athletes and provincial athletes, to determine the differences between the two levels of athletes, and to provide theoretical references for the improvement of scientific training level.

Methods

Ten female athletes were selected as participants for this study, five of whom are national athletes, and the other are provincial athletes. Three-dimensional filming techniques were employed to capture videos of the first and second serve techniques. Simi Motion was applied to obtain the 3D kinematic data. Statistical analyses were performed using IBM SPSS Statistics 27.0, and Mann-Whitney U tests were conducted to determine differences between groups.

Results

Significant differences in kinematics were found between national and provincial athletes. At the moment of the left knee's minimum flexion (T2), in the first serve, national athletes had a smaller shoulder-hip vertical plane angle (-18.281 ± 6.142° vs. -25.631 ± 3.497°; p = 0.047) and a larger hip vertical plane rotation angle (-9.378 ± 4.263° vs. -0.470 ± 4.724°; p = 0.047). In the second serve, national athletes had a smaller hip horizontal plane rotation angle (-1.720 ± 4.683° vs. 24.146 ± 24.014°; p = 0.047) but a larger hip vertical plane rotation angle (-11.553 ± 1.949° vs. -0.422 ± 4.958°; p = 0.009). At the moment of impact (T4), in the second serve, national athletes' batting position (0.296 ± 0.088 m vs. 0.446 ± 0.094 m; p = 0.047) was further back. Additionally, in the second serve, national athletes consistently had their body center of gravity further back at T2 (-0.106 ± 0.052 m vs. -0.018 ± 0.048 m; p = 0.028), T3 (0.002 ± 0.038 m vs. 0.132 ± 0.039 m; p = 0.009), and T4 (0.073 ± 0.050 m vs. 0.217 ± 0.034 m; p = 0.009).

Conclusions

The results of this study indicated several significant kinematic differences between national and provincial athletes, these variations were noted in the shoulder, hip, and body center of gravity. In summary, for the overall first and second serves, it is recommended that national athletes increase the horizontal plane angle of the shoulders and hips at T2, whereas provincial athletes decrease the horizontal plane angle of the shoulder-hip. In addition, provincial athletes need to increase the vertical plane angle of the hip joint, so that the top of the hip can be increased more, and provincial athletes need to be careful not to have the center of gravity too far in front of the body at T2, T3, and T4, so that it can hit the ball at a higher position to increase the swing speed.

The Influence of Kinematics on Tennis Serve Speed: An In-Depth Analysis Using Xsens MVN Biomech Link Technology

An inertial measurement system, using a combination of accelerometers, gyroscopes and magnetometers, is of great interest to capture tennis movements. We have assessed the key biomechanical moments of the serve phases and events, as well as the kinematic metrics during the serve, to analyze their influence on serve speed. Eighteen male competitive tennis players, equipped with the inertial measurement units, performed a prolonged serve game consisting of 12 simulated points. Participants were divided into groups A and B in accordance with their positioning above or below the sample average serve speed. Group A (compared with their counterparts) presented with lower back hip adduction and knee flexion, and a higher leftward thoracic tilt during the impact event (-14.9 ± 6.9 vs. 13.8 ± 6.4, 2.8 ± 5.9 vs. 14.3 ± 13.0 and -28.9 ± 6.3 vs. 28.0 ± 7.3°). In addition, group A exhibited higher maximal angular velocities in the wrist and thorax, as well as a lower maximal angular velocity in the back hip than group B (427.0 ± 99.8 vs. 205.4 ± 9.7, 162.4 ± 81.7 vs. 193.5 ± 43.8, 205.4 ± 9.7 vs. 308.3 ± 111.7, 193.5 ± 43.8 vs. 81.1 ± 49.7°/s). The relevant biomechanical differences during the serve were identified, highlighting the changes in joint angles and angular velocities between the groups, providing meaningful information for coaches and players to improve their serve proficiency.

Relationships Between Force-Time Curve Variables and Tennis Serve Performance in Competitive Tennis Players

ABSTRACT

Fourel, L, Touzard, P, Fadier, M, Arles, L, Deghaies, K, Ozan, S, and Martin, C. Relationships between force-time curve variables and tennis serve performance in competitive tennis players. J Strength Cond Res 38(9): 1667-1674, 2024-Practitioners consider the role of the legs in the game of tennis as fundamental to achieve high performance. But, the exact link between leg actions and high-speed and accurate serves still lacks understanding. Here, we investigate the correlation between force-time curve variables during serve leg drive and serve performance indicators. Thirty-six competitive players performed fast serves, on 2 force plates, to measure ground reaction forces (GRF). Correlation coefficients describe the relationships between maximal racket head velocity, impact height, and force-time curve variables. Among all the variables tested, the elapsed time between the instants of maximal vertical and maximal anteroposterior GRF ( r = -0.519, p < 0.001) and the elapsed time between the instant of maximal anteroposterior GRF and ball impact ( r = -0.522, p < 0.001) are the best predictors of maximal racket velocity. Maximal racket head velocity did not significantly correlate with the mean or maximal vertical GRF or with the mean or maximum rate of vertical force development. The best predictor for impact height is the relative net vertical impulse during the concentric phase ( r = 0.772, p < 0.001). This work contributes to a better understanding of the mechanical demands of tennis serve motion and gives guidelines to improve players preparation and performance. Trainers should encourage their players to better synchronize their upward and forward pushing action during the serve to increase maximal racket head velocity. Players should also aim to improve their relative net vertical impulse to increase impact height through strength training and technical instructions.

Kinematics of the Tennis Serve Using an Optoelectronic Motion Capture System: Are There Correlations between Joint Angles and Racket Velocity?

The serve is the most important stroke in tennis. It is a complex gesture consisting of numerous rotations with a wide amplitude, which are important to manage for performance. The aim of this study was to investigate whether correlations exist between joint kinematic parameters and racket velocity. A quantitative kinematics analysis of four ranked players (two boys and two girls) was carried out using an optoelectronic system composed of 10 cameras (150 Hz). Five flat serves per player were analyzed. Eighty-two markers were located across the 15 body segments and on the racket. A descriptive statistical analysis including a correlation analysis was carried out between joint angles and racket kinematic parameters (vertical position, velocity, and acceleration) during the cocking and acceleration phases. Ten very high (0.7 < r < 0.9) and three almost perfect (r > 0.9) correlations were found. Shoulder and hip axial rotations, knee flexion, and trunk extension were correlated linearly with racket vertical position and velocity during the cocking phase. For the acceleration phase, elbow flexion, trunk flexion/extension, and trunk axial rotation were linked to racket kinematics. Some of these parameters showed differences between slow and fast serves. These parameters, which are involved in transmitting ball velocity, are important to consider for tennis players and coaches in training programs, education, and performance enhancement.

Effects of left-hand contraction on tennis serve performance

Introduction

The tennis serve is commonly executed in high-pressure scenarios, often leading to performance decline; a condition commonly referred to as choking under pressure. One suggested effective method to avert choking involves contracting the left hand. We examined the effects of left-hand contraction on tennis serve performance using a wearable grasping material (polyurethane foam) which can be incorporated into sportswear.

Materials and methods

We assigned 40 right-handed skilled tennis players to either the contraction group (n = 20) or the no-contraction group (n = 20). They were instructed to perform a second-serve task during the pre-test and pressure test. The participants in the contraction group squeezed the grasping material for 20 s before executing the task in the pressure test. We measured performance, including total scores, the number of maximum score achievements, landing positions, and kinematic indices (i.e., ball speed, racket speed, and impact height).

Results

Although neither group demonstrated deteriorated performance on the pressure test, the contraction group experienced an increased number of maximum score achievements under the pressure situation compared with the pre-test (p = 0.021).

Discussion

Our results suggest that when under pressure, left-hand contraction may improve performance during tennis serves.

Neuromuscular Fitness Is Associated with Serve Speed in Young Female Tennis Players

In tennis, the serve plays a key role in determining the success of a player. The speed of a serve is influenced by a multitude of interconnected skills and abilities. The objective of this study was to establish the correlation between the explosive strength of the throwing type, the grip strength and flexibility of the arms, and the shoulder girdle with the serve speed in young female tennis players. Additionally, the study aimed to develop a regression model that accurately predicts the serve speed by analyzing the interplay among these variables. The study was carried out on a group of 20 tennis players, who had an average age of 13.10 ± 0.74 years. Additionally, their height was recorded as 165.70 ± 4.90 cm, and their body mass was measured at 51.45 ± 5.84 kg. To assess the motor abilities of the upper extremities, four tests were used that aimed to measure the explosive strength of the throwing type; one test was for the strength of the hand and forearm muscles, and one test was for the flexibility of the arms and shoulder girdle. Of all the variables examined, the medicine ball throw shot put (MBTSP) (r = 0.75), overhead medicine ball throw (OMBT) (r = 0.70), and grip strength (GS) (r = 0.71) displayed a notable correlation with serve speed (p < 0.05). The results obtained from the multiple regression analysis indicate that the combination of selected predictors (MBTSP-medicine ball throw shot put, OMBT-overhead medicine ball throw and GS-grip strength) explained 75% of the variability in serve speed. Significantly, MBTSP surfaced as the predominant predictor, autonomously elucidating 51% of the variability in serve speed. The importance of improving the analyzed motor skills of young female tennis players to enhance their serve in terms of speed is emphasized by the findings of this research.

Biophysical characterization of the tennis serve: A systematic scoping review with evidence gap map

OBJECTIVES

We aimed to assess the available evidence on the biophysics of the tennis serve, mapping the populations, interventions, contexts and other relevant information to highlight what is already known and to identify gaps in the literature.

DESIGN

Systematic scoping review with evidence gap map.

METHODS

The protocol was designed according to PRISMA 2020, Prisma-ScR guidelines and the Cochrane Handbook. The searches were conducted on July 20, 2022 and updated on April 1, 2023, in PubMed, Scopus and Web of Science (core collection). The risk of bias assessment was performed using the Cochranes method for nonrandomized studies (RoBANS) and a narrative synthesis of the main findings was performed and supplemented with an evidence gap map.

RESULTS

Most trials were found on serve kinematics and kinetics (95 %), analyzing only flat serves (84 and 72 %, respectively). Few trials focused on physiology (20 %; e.g. biomarkers), under-19, left or both-handed, female and intermediate beginner or starter players (29, 17, 8 and 7 %, respectively). We found a preponderance of low and unclear risk of bias (63 and 31 %, respectively) and only 7 % high, particularly, on the assessment of confounding variables.

CONCLUSIONS

The current scoping review reveals a few trials on physiological rather than biomechanical variables, as well as the absence of the kick and slice serve, foot-back and foot-up serve, and left-handed, female, and young player analyses. We did not find systematic mistakes or limitations in the design, conduct, or analysis that would distort the results, since only 7 % presented a high risk of bias.

Is isokinetic shoulder strength a determinant of serve ball velocity in tennis?

The tennis serve is closely related to the quality of the tennis match. However, the isokinetic parameters associated with the tennis serve are still unclear. The aim of this study was to investigate the relationships between ball velocity and isokinetic shoulder strength in tennis serve and to determine isokinetic strength parameters that can predict tennis serve velocity. A total of 13 elite male athletes (16.8 ± 1.5 years) voluntarily participated in the study. The athletes' shoulder internal-external rotation, extension-flexion and abduction-adduction strengths were measured with 5-5-15 repetitions at 60°/s, 180°/s, 240°/s angular velocities. Later, the athletes' 1st, 2nd, and average serve ball speeds were determined using a handheld radar gun. Significant correlations were found between ball speed and isokinetic tennis serve strength (r = 0.556-0.819; p < 0.05). The correlations between ball speed and isokinetic strength performance were higher at 180°/s and 240°/s angular velocities. Extension (240°/s; r = 0.819), flexion (180°/s; r = 0.755), abduction (240°/s; r = 0.733), adduction (240°/s; r = 0.684) and internal rotation (180°/s; r = 0.803) were highly correlated with ball velocity. These findings suggest that strength training to increase the ball speed of the tennis serve should be performed fast at high angular velocities and planning should focus on the strength of extension, flexion, abduction, adduction and internal rotation.

Multidimensional and Longitudinal Approaches in Talent Identification and Development in Racket Sports: A Systematic Review

BACKGROUND

Better methods to support talent identification and development processes may contribute to more effective and efficient athlete development programs in racket sports. Both researchers and practitioners recommend multidimensional and longitudinal approaches to better understand the nature of talent (development). However, the added value of these 'innovative' approaches has not yet been clarified for racket sports. This systematic review intends to gain further insight into the outcomes of multidimensional and longitudinal approaches for talent identification and development in racket sports and to provide directions for future talent research.

METHODS

Electronic searches were conducted in PubMed, Scopus, SPORTDiscus, and Web of Science (January 2000-August 2022). Search terms covered the areas of racket sports and talent in sports. Studies using multidimensional and/or longitudinal talent approaches were included and analyzed regarding the methodology, included performance characteristics (i.e., anthropometrical, physiological, technical, tactical, psychological), and study findings.

RESULTS

A total of thirty-two studies were included using multidimensional (n = 15), unidimensional longitudinal (n = 3) or multidimensional longitudinal designs (n = 14). Most research covered physiological characteristics (n = 28), while fewer articles investigated anthropometrics (n = 21) and technical characteristics (n = 16). Only limited research investigated psychological (n = 4) and tactical characteristics (n = 1). Almost all studies measured physiological characteristics in combination with other characteristics. There was moderate to strong evidence that physiological and technical characteristics have value for athlete development programs in racket sports. Positive but limited evidence was found for psychological and tactical characteristics. Anthropometrical assessments were generally used as controlling variables for maturation. Study designs varied, and many studies used unidimensional statistical models and analyses within multidimensional study designs and datasets.

CONCLUSIONS

This review provides an overview of talent research using multidimensional and/or longitudinal approaches within racket sports and gives guidance on what characteristics to include in decision-making and monitoring processes. However, it remains difficult to draw conclusions about the added values of these approaches due to their variety in methodology. Future talent research should include more consistent study designs and conduct multidimensional and longitudinal studies using multivariate statistical approaches that benefit from the data's multidimensionality.

Comparison of the activation and mechanical properties of scapulothoracic muscles in young tennis players with and without scapular dyskinesis: an observational comparative study

BACKGROUND

In tennis athletes with scapular dyskinesis, the activation of the scapulothoracic muscles during serve is not known. Also, the mechanical properties (tone, elasticity, and stiffness) of the scapulothoracic muscles of the tennis athletes with scapular dyskinesis are likely to change. The study aimed to evaluate the activation of the scapulothoracic muscles while performing tennis serve and to determine the changes in the mechanical properties of the same muscles in young tennis athletes with scapular dyskinesis.

METHODS

Seventeen tennis athletes with scapular dyskinesis aged between 11 and 18 years (the scapular dyskinesis group) and age- and gender-matched 17 asymptomatic tennis athletes (the control group) were included in the study. Activation of scapulothoracic muscles (descending-transverse-ascending trapezius and serratus anterior) in the 3 phases (preparation, acceleration, and follow-through) of the serve was evaluated using surface electromyography, and the mechanical properties of the same muscles were measured at rest by myotonometry.

RESULTS

Ascending trapezius activation in the follow-through phase was lower in the scapular dyskinesis group compared with the control group (mean difference 95% confidence interval: -22.8 [-41.2 to -4.5]) (P = .017). The tone and stiffness of the transverse trapezius (P = .043 and P = .017, respectively) were higher, whereas the same parameters of the ascending trapezius were lower (P = .008 and P = .010, respectively) in the scapular dyskinesis group compared with the control group.

CONCLUSIONS

Activation of the ascending trapezius and the tone and stiffness of the transverse-ascending trapezius were altered in tennis athletes with scapular dyskinesis. Implementations to improve these changes can be included in the rehabilitation or training programs of young tennis athletes with scapular dyskinesis.

Six-Week Joint-Specific Isometric Strength Training Improves Serve Velocity in Young Tennis Players

PURPOSE

Evaluate the effects of 6 weeks of specific-joint isometric strength training on serve velocity (SV), serve accuracy (SA), and force-time curve variables.

METHODS

Sixteen young competition tennis players were divided into an intervention (n = 10) or control group (n = 6). SV, SA, maximal voluntary isometric contraction, peak rate of force development, rate of force development, and impulse (IMP) at different time frames while performing a shoulder internal rotation (SHIR) or flexion were tested at weeks 0, 3, and 6.

RESULTS

The intervention group showed significant increases in SV from pretest to posttest (7.0%, effect size [ES] = 0.87) and no variations in SA. Moreover, the intervention group showed significant increases from pretest to posttest in shoulder-flexion rate of force development at 150 (30.4%, ES = 2.44), 200 (36.5%, ES = 1.26), and 250 ms (43.7%, ES = 1.67) and in SHIR IMP at 150 (35.7%, ES = 1.18), 200 (33.4%, ES = 1.19), and 250 ms (35.6%, ES = 1.08). Furthermore, significant increases were found in shoulder-flexion rate of force development from intertest to posttest at 150 ms (24.5%, ES = 1.07) and in SHIR IMP at 150 (13.5%, ES = 0.90), 200 (19.1%, ES = 0.98), and 250 ms (27.2%, ES = 1.16). SHIR IMP changes from pretest to intertest were found at 150 ms (25.6%, ES = 1.04). The control group did not show changes in any of the tested variables.

CONCLUSIONS

Six weeks of upper-limb specific-joint isometric strength training alongside habitual technical-tactical workouts results in significant increases in SV without SA detriment in young tennis players.

EFFECTS OF FUNCTIONAL TRAINING ON THE HITTING QUALITY OF TENNIS PLAYERS

ABSTRACT Introduction: Functional training values the athletes’ physical activity and the integral exercise proper of the practiced sport. Tennis frequently integrates this exercise into regular training, aiming to enrich teaching. Objective: Compare the effects of functional training in daily exercise on the tennis players’ strokes based on the athletes’ performance. Methods: A research sample of 18 young male tennis players in tennis clubs were used. The volunteers were randomly divided into two groups, control and experimental. The control group received traditional physical training methods in their daily training. The experimental group had functional physical training added to their daily training. Before and after training, the ITN and functional movement screening methods were used to study the hitting quality of the tennis players. Finally, a mathematical and statistical analysis of the results ascertained in the tests was performed. Results: After 12 weeks, the mean level and accuracy of the experimental group were significantly higher (P<0.05). The control group showed a slight improvement in the mean level and ball accuracy but without statistical significance (P>0.05). Conclusion: Functional training associated with regular training positively improved the quality of hitting in tennis players. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion and serve performance in competitive young tennis players

Introduction

Intensive tennis practice is known to generate sport-specific adaptations at the shoulder region and influence the sagittal spinal curvature. However, increased thoracic kyphosis decreases the shoulder functional capacity, which could limit tennis performance. Therefore, the aim of this study was to investigate the effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion, and serve performance in competitive young tennis players.

Methods

Eighteen male and four female players (age: 16.0 ± 2.4 years, height: 170.7 ± 11.0 cm; mass: 62.1 ± 11.5 kg; International Tennis Number: 3-4) performed their regular training during 8 weeks, which was used as a reference period, and implemented a multimodal program including stretching, strengthening, and myofascial release exercises, four times per week during 8 additional weeks, which corresponded to the intervention period. The thoracic curvature angle and mobility, the biacromial and interscapular distances, the glenohumeral range of motion and the tennis serve performance were assessed three times, i.e., before and after the regular training and after the 8-week multimodal program.

Results

The results showed that the 8-week regular training had no significant effects on thoracic curvature angle [effect size (ES) = 0.02-0.36, p = 0.06-0.46] and mobility (ES = 0.05-0.26, p = 0.13-0.42), biacromial (ES = 0.05, p = 0.18) and interscapular distances (ES = 0.03, p = 0.45), ranges of motion in glenohumeral internal (ES = 0.04, p = 0.43) and external rotation (ES = 0.43, p = 0.06), and tennis serve accuracy (ES = 0.33, p = 0.07) and velocity (ES = 0.09, p = 0.35). The 8-week multimodal program increased moderately the thoracic mobility (ES = 0.55, p = 0.01), moderately to strongly the serve accuracy and velocity (ES = 0.65, p = 0.003, for both), strongly decreased the interscapular distance (ES = 1.02, p < 0.001), and strongly increased the range of motion in glenohumeral internal (ES = 0.90, p < 0.001) and external rotation (ES = 1.49, p < 0.001).

Discussion

These findings indicated that an 8-week multimodal program, including spine and glenohumeral mobility and shoulder girdle strength exercises, performed four times per week during 8 weeks, is moderately relevant to rectify the sagittal thoracic curvature in competitive tennis players, while such a program may help regain the range of motion in glenohumeral rotation without tennis serve performance impairment.