Energy Expenditure of Elite Male and Female Professional Tennis Players During Habitual Training

Understanding the daily energy expenditure of athletes during training is important to support recovery, adaptation, and the maintenance of performance. The aim of the current research was to assess the total daily energy expenditure (TDEE) and the acute energy expenditure (EE) of tennis training sessions during habitual training of elite tennis players. Using a cohort study design, 27 (n = 10, male; age; 22.3 ± 3.2 years and n = 17, female; age: 23.8 ± 3.5 years) elite singles tennis players were assessed for TDEE and tennis training EE. Using Actiheart activity monitors during a 2- to 5-day training period, male players were analyzed for 26 days and 33 (1.3 ± 0.5 sessions/day) tennis training sessions, and female players for 43 days and 58 (1.2 ± 0.4 sessions/day) tennis training sessions. Male TDEE (4,708 ± 583 kcal/day) was significantly higher than female (3,639 ± 305 kcal/day). Male absolute and relative tennis training EEs (10.2 ± 2.3 kcal/min and 7.9 ± 1.4 kcal·hr-1·kg-1) were significantly higher than those of females (7.6 ± 1.0 kcal/min and 6.8 ± 0.9 kcal·hr-1·kg-1). The resting metabolic rate was assessed via indirect calorimetry. The physical activity level for both groups was 2.3 AU. The TDEE of male and female players during habitual training now highlights the continual cycle of high energy demands experienced by the elite tennis player. The broad ranges of TDEE and EE reported here suggest individual assessment and nutritional planning be prioritized, with a particular focus on carbohydrate requirements.

Development of Upper-Extremity Morphological Asymmetries in Male and Female Elite Youth Tennis Players: A Longitudinal Study

PURPOSE

This 2-year longitudinal study examined the development of upper-extremity bone mineral density (BMD), bone mineral content (BMC), and lean mass (LM) asymmetry magnitudes in male and female youth tennis players.

METHODS

Dominant and nondominant upper-extremity BMD, BMC, and LM values of 49 male and 31 female players were measured yearly using dual X-ray absorptiometry. From these values, asymmetry magnitudes were calculated and expressed as a percentage. Maturity offset was estimated using anthropometric measurements. Linear mixed effect models examined the development of BMD, BMC, and LM asymmetry magnitudes according to players' maturity offset, sex, and training volume.

RESULTS

Adjusted for sex and training volume, a 1-year increment in maturity offset was associated with a significant increase in BMD (1.3% [2.2%]; P < .001) and BMC (0.6% [2.4%]; P = .011) asymmetry magnitudes. Male players displayed significantly higher LM asymmetry magnitudes (Δ3.2% [8.4%]; P = .002) compared with their female counterparts. Training volume was not significantly associated with asymmetry magnitude development.

CONCLUSION

In contrast to LM, male and female youth tennis players' upper-extremity bones are still responsive to mechanical loading with a significant increase in BMD and BMC asymmetry magnitudes according to maturity offset.

Effect of table tennis balls with different materials and structures on the hardness and elasticity

The new material introduced by the ITTF in 2014 for table tennis balls has attracted significant attention from players and coaches. Changes in both material selection and production procedures are likely to have affected the static performance of the ball. However, the raw data regarding the elasticity and hardness of these new material balls, encompassing various brands and structures, often lacks practical information crucial for players' rapid adaptation and daily training. The static properties tested in this study were provided by the ITTF, covering both hardness and elasticity. Based on computed variables, this study revealed that the hardness of seam balls at the equator was not consistently higher than that at the pole. Additionally, the study confirmed that the hardness and bounce height of new material balls exceeded those of celluloid. Furthermore, correlation analysis was conducted to examine the relationship between these two properties, revealing a significant correlation between the hardness of seamless balls and their elasticity. This study provides an analysis of the static performance of various types of new material balls, aiding players and coaches in better understanding official event balls and offering a theoretical foundation for the formulation of diverse training and game strategies.

Reliability of Accuracy and Precision Tests for Elite Para Table Tennis Players

The primary purpose of this study was to adapt selected accuracy and precision tests in table tennis to the specific skills of elite table tennis players with impairment. The study included a sample of 23 Para table tennis players with an average age of 31.8 ± 12.22 years (including 30.4% females) who belonged to the senior Polish Para table tennis team. A battery of six tests evaluating stroke accuracy and serve precision was assessed. The analysis of the reliability of these tests confirmed the legitimacy of using this battery of accuracy and precision tests to assess the skills of Para table tennis players in all three integrated sport classes: players in wheelchairs, in a standing position, and with intellectual impairment. Analysis of the data obtained from the tests could provide coaches with relevant information regarding elite Para table tennis players' level of performance and examine selected accuracy and precision elements of their individual technique.

Musculoskeletal Injuries in Table Tennis during Competition: A Systematic Review

The study aimed to investigate the incidence of musculoskeletal injuries among table tennis players and identify their associated risk factors. We conducted a literature search in online databases using relevant search terms related to "table tennis" and "injury". To compare the rate of injuries according to player-related variables, we extracted information on sex, level of games, circumstances of injury, and duration of sport absence after injury. Furthermore, we calculated the odds ratios based on the number of injuries according to variables. Eight articles included 873 professional table tennis players, revealing an overall musculoskeletal injury rate of 3.6% (31 musculoskeletal injuries). The incidence was 10.0 injuries per 1,000 playing hours (range, 0-27.0). The rate of musculoskeletal injuries for female and male players were 3.2% and 3.8%, respectively, and those for Summer Olympic Games, Asian Games, and domestic national games was 4.8%, 15.4%, and 0%, respectively. More than half (52%) of injuries occurred during training, and most injuries (64%) were of a nature that did not cause time loss. This review provides valuable information about the incidence of musculoskeletal injuries in table tennis competitions. However, owing to the limitations of this study in identifying injury-related risk factors, future studies analyzing comprehensive variables are required.

Mass Participation and Tournament Event Management for the Team Physician: A Consensus Statement (2022 Update)

ABSTRACT

Mass participation events include endurance events (e.g., marathon, triathlon) and/or competitive tournaments (e.g., baseball, tennis, football (soccer) tournaments). Event management requires medical administrative and participant care planning. Medical management provides safety advice and care at the event that accounts for large numbers of participants, anticipated injury and illness, variable environment, repeated games or matches, and mixed age groups of varying athletic ability. This document does not pertain to the care of the spectator.

Elbow, wrist kinematics and shock transmission of backhand stroke in wheelchair tennis players

The aim was to compare the differences in kinematics of elbow and wrist and shock transmission of the upper extremity in wheelchair tennis players and able-bodied players (in standing and sitting position) during backhand strokes. Fifteen wheelchair tennis and 15 able-bodied tennis players enrolled. Electromagnetic system and trial-axial accelerometers were used to measure the difference in the kinematic parameters of the upper extremity and the impact vibration transferred across the wrist joint. The results indicated that wheelchair players demonstrated unique elbow and wrist kinematics, especially shorter total swing time, greater elbow flexion at preparation, lower wrist extension acceleration before impact, and smaller racket vibration at impact. Comparing to able-bodied players in standing, wheelchair players and players in sitting demonstrated significantly greater elbow joint flexion/extension angle, angular velocity, angular acceleration during extension, and wrist joint flexion angle. Wheelchair players also differ significantly with the players in sitting regarding elbow joint angular velocity and acceleration, and wrist joint flexion velocity. These adaptations and adjustments can be attributed to the missing lower extremity function and deficient trunk kinetic chain. The differences between wheelchair tennis players and able-bodied players in sitting could represent the progress as the wheelchair players moving from novices to experts.

Mass Participation and Tournament Event Management for the Team Physician: A Consensus Statement (2022 Update)

ABSTRACT

Mass participation events include endurance events (e.g., marathon, triathlon) and/or competitive tournaments (e.g., baseball, tennis, football (soccer) tournaments). Event management requires medical administrative and participant care planning. Medical management provides safety advice and care at the event that accounts for large numbers of participants, anticipated injury and illness, variable environment, repeated games or matches, and mixed age groups of varying athletic ability. This document does not pertain to the care of the spectator.

Plantar load distribution with centers of gravity balance and rearfoot posture in daily lives of Taiwanese college elite table tennis players: a cross-sectional study

Background

Table tennis is an asymmetric sport involving the powerful forward swing of the upper limbs depends on the solid support of the lower limbs. The foot drive really affects the weight balance and stroke accuracy even though the distance and momentum of the lower limb displacement are limited within a limited range. Given that previous research on table tennis has typically focused on the footwork and stroke performance of professional players, the study aimed to investigate the daily static and dynamic plantar load distribution as well as the centers of gravity balance and rearfoot posture among Taiwanese college elite table tennis players.

Methods

This is a cross-sectional study of 70 elite male table tennis players (age: 20.0 ± 0.9 years; height: 173.4 ± 5.1 cm, weight: 67.6 ± 5.3 kg, experience: 10.0 ± 1.6 years) and 77 amateur table tennis players of the same gender (age: 20.1 ± 0.8 years, height: 167.4 ± 4.4 cm, weight: 64.3 ± 4.0 kg, experience: 4.4 ± 1.2 years) from Taiwanese universities. The JC Mat optical plantar pressure analyzer was applied to determine the plantar load distribution along with arch index (AI) and centers of gravity balance. Assessment of rearfoot postural alignment was mainly used to contrast the performance of the centers of gravity balance.

Results

The static arch indices of both feet in the elite group were symmetrical and considered normal arches (AI: 0.22 ± 0.07) during their non-training and non-competition daily lives. Their static plantar loads were symmetrically concentrated on the bipedal lateral metatarsals (P < 0.05) as well as shifted to the medial and lateral heels (P < 0.05) and the lateral metatarsals (P < 0.05) during the walking midstance phase. Additionally, the plantar loads were mainly applied to the bipedal medial (P < 0.01) and lateral heels (P < 0.05) during the transitional changes between both states. Elite athletes had symmetrical and evenly distributed centers of gravity on both feet (left: 50.03 ± 4.47%; right: 49.97 ± 4.47%) when standing statically, along with symmetrical rearfoot angles and neutral position of the subtalar joint (left: 2.73 ± 2.30°; right: 2.70 ± 2.32°) even though they were statistically lower than those of the amateur athletes (P < 0.05).

Conclusions

The daily static and dynamic foot patterns of Taiwanese college elite table tennis players were characterized by plantar load distribution on the lateral metatarsals and the entire calcaneus along with balanced centers of gravity and normal rearfoot posture. This foot and posture layout outlines the excellent athletic performance of the foot and ankle in professional athletes. Portions of this text were previously published as part of a preprint (https://doi.org/10.21203/rs.3.rs-2993403/v1).

The relative age effect and its influence on athletic performance in Chinese junior female' tennis players

The relative age effect (RAE) has been the focus of numerous studies; however, there are still fewer studies in women's sports than in men's sports. In this study, all female players (N = 2,255) who participated in Chinese junior tennis competitions (U12, U14, U16, and the National Junior Team) from 2014 to 2019 were investigated in terms of competitors' birth dates and year-end rankings. For the purposes of the analysis, the birth dates were also separated into quarters and half years. The study's objectives were to analyze the prevalence of the RAE among young Chinese female tennis players and to further examine how the RAE affects athletic performance. Differences between the observed and expected distributions of birth dates were tested using the chi-square statistic, and subsequent calculations were tested using odds ratios. The RAE was discovered to be present in every group of Chinese junior female tennis players (p < 0.001), with the proportions of those born in the first half of the year being 56.4% (U12), 53.1% (U14), and 57.0% (U16), respectively. The RAE for athletes selected for the National Women's Junior Tennis Team was even more significant, with the percentage of birth dates in the first half of the year at 61.2%. Finally, we observed a tendency for the effect of the RAE on the athletic performance of adolescent female tennis players to diminish with age.

The interaction between wheelchair configuration and wheeling performance in wheelchair tennis: a narrative review

The number of wheelchair tennis players is rising internationally, yet from a scientific perspective little is known about wheelchair tennis performance. Wheelchair tennis is more complex compared to other wheelchair court sports, due to the wheelchair/racket interaction. The purpose of this narrative review was to gain insight into the influence of wheelchair configuration, i.e., the individual set-up of a wheelchair, on wheelchair tennis performance, more specifically on wheelchair mobility performance and propulsion technique. Wheelchair propulsion while holding a racket has had little attention in both the wheelchair mobility performance and wheelchair propulsion technique area. It is shown that the propulsion technique and wheelchair mobility performance are negatively affected by the racket. Based on the current literature, the influence of wheelchair configuration on wheeling performance in wheelchair tennis can mainly be described from a broader wheelchair court sport perspective, due to the lack of specific publications about wheelchair tennis. In the future more research should be conducted on wheeling performance and wheelchair configuration in wheelchair tennis, to attain a more proper scientific foundation for optimising wheelchair tennis performance.

Navigating the Court: A Comparison of Distance Demands between Sexes in Grand Slam Tennis

This study analysed critical movement demands of tennis match-play to better inform contemporary approaches to athlete preparation and training. HawkEye data from matches during the 2021 and 2022 Australian Open were utilised. Distance was aggregated for movement cycles, points, games, sets, and matches, alongside total shots played. Data was collated for males (best-of-five sets) and females (best-of-three sets) allowing comparisons both within and between sexes. Overall, no differences within sexes were evident for total distance, however males traversed further per match than females (MDE = 809 ± 139m, ES = 0.86). Female players travelled further in their deciding (third) sets compared to set 1 (ES = 0.28) and while this effect wasn't as discernible for males, the deciding (fifth) set showed some evidence of elevated distance requirements and variability. Between sexes, only female set 3 was different to male set 3 (ES = 0.29). Female and male tiebreak games (i.e. game 13) required players travel further distance compared to other games (ES = ~1.45). Between sex differences were observed for tiebreak games compared to games 1 to 12 (female ES = 1.36 and male ES = 1.53). Players from both sexes generally covered similar distances during points and movement cycles, with between-shot distances of 4.2m-4.5m, notably longer than previous reports. Further, total shots and total match distance (r > 0.97; p < 0.01) shared similar linear relationships. These results highlight that the between shot or movement cycle demands of professional hard court tennis are substantially higher than described in the literature (Roetert et al., 2003). The findings also reveal competitiveness as a key influence on set level distance demands during professional tennis match-play, a consideration in player preparation programs.

Common Wrist-Extensor Tendon and Pectoralis Muscle Stiffness in Healthy Recreational Tennis Players

CONTEXT

Imbalances in upper-extremity soft tissue stiffness may play a role in the development of shoulder and elbow musculoskeletal injuries in tennis players. Ultrasound shear wave elastography provides quantifiable and specific data regarding muscle stiffness. The purpose of this study was to compare tendon and muscle stiffness in healthy tennis players to nontennis players.

DESIGN

Cross-sectional study.

METHODS

The shear wave modulus, measured in kilopascals, was obtained for the dominant pectoralis major, pectoralis minor, and common wrist-extensor tendon using 2-dimensional shear wave elastography ultrasound imaging (GE Logiq S8, L9 linear transducer). Independent t test was run to compare age, body mass index, and the activity index score between both groups. Within-day intrarater reliability was assessed using a within-examiner intraclass correlation coefficients (ICC [3, 1]) with 95% confidence intervals. A multivariate general linear model was run to compare the mean differences between the tennis and nontennis players for each of the soft tissues.

RESULTS

Twenty-six individuals (13 tennis players and 13 nontennis players) were recruited. Within-day ICCs were very good (ICC > .78 for the pectoralis musculature) and excellent (ICC > .94 for the common wrist extensor). Common extensor tendon stiffness was significantly higher in tennis players compared to nontennis players (mean difference = 114.8 [61.8], confidence interval, -22.8 to 252.5 kPa for the dominant arm [P = .039]). Mean pectoralis major and minor stiffness differences were not significant (P > .214).

CONCLUSIONS

Common wrist-extensor stiffness in healthy recreational tennis players is higher than those who do not play tennis. Therefore, clinicians may need to facilitate a greater soft tissue stiffness response with resistance training when rehabilitating recreational tennis players as compared to those not playing tennis. Additional normative data on a larger sample of recreational tennis players should be collected.

Mental Fatigue Impairs Second Serve Accuracy in Tennis Players

Purpose: The aim of this 2-week randomized, counterbalance and crossover study was to investigate the effect of acute mental fatigue (MF) on tennis serve performance and accuracy in tennis players. Methods: Ten male tennis players (18 ± 4 years, 1.80 ± 0.08 m; 71 ± 13 kg) were randomized to either the MF group (N = 5) that underwent an acute MF protocol or to a control (CON) group (N = 5). The MF condition consisted in a 30-min modified Stroop color word task performed before on-court serve speed test. A visual analogue scale (VAS) was used to assess the perceptions of MF and motivation toward the upcoming technical tests. Results: Reduction over baseline score of Stroop test was noted in accuracy (N < .001), but not in reaction time (N = .968) in the MF group. Increments in perceived workload were detected (N < .001) in MF group compared to CON. No differences for first and second serve speed from deuce and advantage side were observed. Increment of percentage of failed second serves from the deuce side (N = .043) in MF were detected. Conclusions: An acute MF protocol reduced tennis serve accuracy from deuce side in male tennis players. Players should avoid cognitive efforts before training sessions and matches to prevent negative effects of their technical performance.

The Divergent Effects of Resilience Qualities and Resilience Support in Predicting Pre-Competition Anxiety and Championship Performance

Purpose: Psychological resilience is vital to the development of sport talents. Qualitative research has consistently demonstrated that sport resilience encapsulates a mixed package of resilience qualities (reflecting positive traits and characteristics) and resilience support (reflecting perceived support and related resources). Ironically, sport resilience research adopting quantitative methods has been assessing resilience as a unidimensional construct, with little attention to the multi-facet nature of resilience and its effects on performance. In the present research, we tested a novel proposition that resilience qualities predict reduced pre-competition cognitive anxiety and contribute to performance more than resilience support. Methods & Results: Across two samples of competitive table tennis players (Study 1: N = 196 competing at province level; Study 2: N = 106 competing at national level), we consistently found resilience qualities, rather than resilience support, predicted lower levels of pre-competition cognitive anxiety and superior performance at a national championship. Results also suggest that pre-competition cognitive anxiety mediated the relationship between resilience qualities and performance. Conclusion: The findings provide the first evidence supporting the divergent effects of resilience qualities and resilience support in predicting pre- competition anxiety and championship performance and call for the consideration of such a distinction when designing and delivering resilience programs.

Quantifying Change of Direction Movement Demands in Professional Tennis Matchplay: An Analysis From the Australian Open Grand Slam

ABSTRACT

Giles, B, Peeling, P, and Reid, M. Quantifying change of direction movement demands in professional tennis matchplay: An analysis from the Australian Open Grand Slam. J Strength Cond Res 38(3): 517-525, 2024-Change of direction (COD) contributes significantly to the movement repertoire of professional tennis players, yet the time-motion and degree demands of these changes are poorly understood. This study examines the velocity, acceleration, and angular displacement profiles of COD movements in modern professional tennis. One hundred eighty-two singles matches of Hawk-Eye player tracking data collected from the Australian Open Grand Slam were used for analysis. A novel COD classification algorithm was used to identify >120,000 medium and high-intensity CODs for analysis. Descriptive characteristics of the COD performance were calculated using player coordinate and time variables. Sex comparisons were analyzed using 2 mixed-effects models assessed for differences via likelihood ratios. Players performed 1.6 CODs per point. Both sexes executed, on average, 1.3-1.4 shots and covered 4.8 m per COD, with men performing changes every 2.7 seconds and women every 3.1 seconds. Medium-intensity COD comprised 88-94% of all identified changes. Approximately 2 in 3 CODs involved a degree of change >105°, whereas cutting maneuvers (<45°) were most commonly high-intensity COD. This study is the first to quantify the COD characteristics of professional tennis matchplay. Both sexes performed the same average number of CODs per point, however, men executed high-intensity changes twice as frequently as women, at an average of 1 every 5 points. These novel findings will help to improve the specificity of training interventions in elite tennis conditioning.

Using simulations to compare the current Davis Cup ranking system to Elo

The Davis Cup is the premier men's team event in tennis, run by the International Tennis Federation and in which over 130 nations compete. It uses a merit-based ranking system that allows nations to gain a pre-determined number of points when they win. The rankings are integral to the competition structure and used in the draws of every round. Therefore, it is essential that the ranking method performs well with respect to required performance criteria of the International Tennis Federation. The Elo rating method is a commonly used method of rating and ranking participants in a competitive exercise and is used by FIFA for the ranking of male and female national teams. The performance of the current Davis Cup ranking method and Elo rating were compared using a simulation of the Davis Cup competition structure. Four criteria were used for the comparison: Finishing Order Correlation, Skill Level Correlation, Responsiveness, and Protection. Such a comparison has not previously been published. The two methods were comparable across three of the criteria, with the Davis cup easily outperforming Elo in responsiveness. Indeed, the Elo method had such poor responsiveness that improved performance may not be fully recognised within a player's career. An alternative method of optimising the Elo K-factor parameter was developed and this improved the performance of Elo to match the current Davis Cup method. In conclusion, the current Davis Cup ranking method is performing at a standard that cannot be matched by typically optimised Elo but can be matched when an alternative optimisation method is used. Therefore, no evidence was found to suggest that the current Davis Cup ranking method could be improved upon by using Elo. However, alternative K-factor optimisation methods should be considered when applying Elo to a competition.

Table tennis motion recognition based on the bat trajectory using varying-length-input convolution neural networks

Action recognition has been applied in fields such as smart homes, gaming, traffic management, and security monitoring. Motion recognition is helpful for biomechanical analysis, auxiliary training systems, table tennis robots, motion-sensing games, virtual reality and other fields. In our study, we collected data on table tennis skill motion, created the TTMD6 dataset, and analyzed the characteristics of table tennis paddle trajectories. We propose a motion recognition algorithm to recognize paddle trajectories. Other research has used multijoint data to identify actions, while we use only the paddle trajectory to recognize table tennis skill motions, accelerating the speed of motion recognition. Therefore, it is feasible to use paddle trajectories to recognize table tennis skill motions.

Effects of high-intensity interval training on strength, speed, and endurance performance among racket sports players: A systematic review

This study aims to present a critical review of the existing literature on the effects of High-Intensity Interval Training (HIIT) on strength, speed, and endurance performance among racket sports athletes. This study conducted a systematic literature review by PRISMA guidelines. Various well-known academic and scientific databases were used for research collection, including PubMed, EBSCOhost, Scopus, Web of Science, and Google Scholar. Out of 27 relevant studies, 10 were selected for inclusion in this systematic review, all meeting the required inclusion criteria. The quality of each study was assessed using the PEDro scale, with scores ranging from 3 to 5 for the selected studies. HIIT was found to improve racket players' VO2 max (maximum oxygen uptake), running and repetitive sprint performance, jumping performance, and hitting speed during play. Current findings indicate that HIIT can significantly benefit athletic performance. Long-term HIIT allows athletes to enhance their power while improving crucial variables related to both aerobic and anaerobic endurance. This anaerobic endurance and explosive power type is particularly vital for racket sports players. For example, athletes in table tennis and badminton must exert maximum effort during high-intensity middle and back-court play. Racket athletes also need to maintain a stable state while preserving ball speed and positioning, and must quickly recover to prepare for the next rally. This training mechanism can assist athletes in honing their skills and achieving more efficient hitting quality. Therefore, this paper recommends that racket sports athletes incorporate HIIT into their regular training routines. The suggested frequency is three times per week, with each training session lasting 30-40 minutes, and a total duration of six to eight weeks. Trial registration. Systematic Review Registration: [https://inplasy.com/], identififier[INPLASY20230080].

Quantifying motor adaptation in a sport-specific table tennis setting

Studies on motor adaptation aim to better understand the remarkable, largely implicit capacity of humans to adjust to changing environmental conditions. So far, this phenomenon has mainly been investigated in highly controlled laboratory setting, allowing only limited conclusions and consequences for everyday life scenarios. Natural movement tasks performed under externally valid conditions would provide important support on the transferability of recent laboratory findings. Therefore, one major goal of the current study was to create and assess a new table tennis paradigm mapping motor adaptation in a more natural and sport-specific setting. High-speed cinematographic measurements were used to determine target accuracy in a motor adaptation table tennis paradigm in 30 right-handed participants. In addition, we investigated if motor adaptation was affected by temporal order of perturbations (serial vs. random practice). In summary, we were able to confirm and reproduce typical motor adaptation effects in a sport-specific setting. We found, according to previous findings, an increase in target errors with perturbation onset that decreased during motor adaptation. Furthermore, we observed an increase in target errors with perturbation offset (after-effect) that decrease subsequently during washout phase. More importantly, this motor adaptation phenomenon did not differ when comparing serial vs. random perturbation conditions.

Attentional focus strategies in racket sports: A systematic review

The body of evidence has shown that the external focus of attention (EF) rather than the internal focus of attention (IF) enhances motor skill learning and performance. Within racket sports which require a high level of motor control, anticipation skills, and mental preparedness, effectively directing attention is essential to elicit improvements in athletic performance. The present review aimed to evaluate the scientific evidence concerning the effects of attentional focus instructions on motor learning and performance in racket sports. We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The study was registered with the Open Science Framework (osf.io/m4zat). Four electronic databases (Web of Science, Scopus, MEDLINE, and SPORTDiscus) were searched for original research publications. Inclusion criteria were: peer-reviewed journals; healthy and free from injury participants; attentional focus literature specific to the external or internal focus; attentional focus related to motor learning or motor performance; studies included at least one comparator (e.g., different attentional focus group, or control groups with neutral or no specific instruction); publications in which task(s) or skill(s) related to one of the racket sports (tennis, table tennis, badminton, squash, or padel). The initial search yielded 2005 studies. Finally, 9 studies were included in the quantitative analysis. Overall, the results indicated that EF benefits the learning and performance of racket sport skills, compared to IF and over control conditions. The findings suggest that coaches and practitioners should consider the adoption of EF to optimize racket skills performance, particularly in novice or low-skilled athletes.

Characteristics of physical activity during beginner-level group tennis lessons and the effect daily activity

Tennis is a popular leisure sport, and studies have indicated that playing tennis regularly provides many health benefits. We aimed to clarify the characteristics of physical activity during beginner-level group tennis lessons and daily physical activity of the participants. Physical activity was measured using an accelerometer sensor device for four weeks, including the 80-min duration tennis lessons held twice a week. Valid data were categorized for tennis and non-tennis days. The mean physical activity intensity during the tennis lesson was 3.37 METs. The mean ratio of short-bout rest periods to the tennis lesson time in 90 and 120 s was 7% and 4%, respectively. The mean physical activity intensity was significantly higher (p < 0.0001) and the duration of vigorous-intensity physical activity (VPA) was increased in 76% of participants on days with tennis lessons compared to without tennis lessons. Beginner-level tennis lesson has characteristics of less short-bout rest physical activity than previously reported competitive tennis match and increased the duration of VPA in daily activity compared to without tennis lessons, suggesting that beginner-level tennis lessons contribute physical activity of health benefits.

Comprehensive secondary prevention of lateral epicondylitis in young tennis players

The research aims to increase the efficiency of the training process for young tennis players old based on lateral epicondylitis secondary prevention methods. Tennis players with apparent residual effects of lateral epicondylitis were selected for the study and divided into experimental (18 boys and 14 girls) and control groups (18 boys and 13 girls). The experimental group was trained according to the developed technique, and the control group as per standard one. The results of goniometry in the experimental group showed the normalization of the motion amplitude in extension and supination. The motor density of the training session applying the complex technique for the secondary prevention of lateral epicondylitis in the experimental group increased on average from 66.6% to 82.2% in boys and from 65.7% to 80.0% in girls.

Prenatal androgenization (2D:4D) predictions of tennis match-play success in junior players: A search for physiological explanations

AIM

This study aims to investigate the possible association between digit ratio (2D:4D) and match-play success (MPS) in junior tennis players. In addition, we consider the possible explanatory pathways of these associations in relation to psychological, strength, power, and hormonal parameters.

METHODS

We performed a cross-sectional study, with a sample comprised of 64 male junior tennis players (11-18 years old). Digit ratio was calculated from direct finger measurements. In addition, we measured the ratio of wins by number of matches played in 5 years of official competition (MPS), handgrip strength (HGS), standing long jump (SLJ), training (in weekly hours), and expertise (number of years in official competition). Salivary testosterone and cortisol levels were measured before and after physical "challenge" tests.

RESULTS

The 2D:4D correlated negatively with HGS and SLJ. MPS was also negatively associated with 2D:4D, but was positively correlated to HGS, expertise, training, and self-confidence (SC). Multiple linear regression showed 2D:4D and expertise were associated with MPS (43%-54%). None of the physical, or hormonal variables tested explained the links between 2D:4D and MPS.

CONCLUSION

Therefore, the specific fitness components influenced by prenatal androgenization that moderate sports success remain unknown. Future studies should explore the interaction of 2D:4D, with tennis exercises as a challenge to induce hormonal change, the effect of pubertal stage, and the influence of aerobic endurance in determining MPS.

Early absorption sources of caffeine can be a useful strategy for improving female table tennis players-specific performance

BACKGROUND

The consumption of fast absorption sources containing caffeine, such as caffeinated gum and coffee mouth rinsing, has been considered a practical nutritional strategy among athletes. Therefore, this study aimed to determine the effect of early absorption sources containing caffeine on the performance of female table tennis players.

METHOD

Eighteen female table tennis players randomly participated in this randomized, double-blind, and crossover designed study. Before starting the test, the participants attended a familiarization session. In each test session, participants were randomly assigned to one of three conditions including chewing caffeinated gum (CG, n = 6), coffee mouth rinsing (CMR, n = 6) and placebo capsule (PLA, n = 6). All participants consumed caffeine with an average dose of ∼3 to 4.5 mg·kg-1. The one-week interval was considered a washout period for each condition. Each test session included measurement of functional, skill and cognitive tests. Skill tests included serve, forehand drive, backhand push and counter tests. The Cognitive function measured by color recognition test, and functional tests included agility, hand movement speed, the explosive power of the upper body and lower body, hand-eye coordination and hand grip strength tests. The collected data were analyzed (with SPSS Windows software) by repeated measure ANOVA analysis and Bonferroni post hoc test at P ≤ 0.05 level.

RESULTS

The findings of the present study illustrated that CG and CMR increased significantly agility and reduced the amounts of errors in the cognitive test compared to PLA (p < 0.05), While there was no significant difference between CG and CMR (p > 0.05). Also, CG and CMR compared to PLA and CMR compared to CG rose significantly hand movement speed and movement speed (p < 0.05), and CMR compared to PLA increased significantly hand-eye coordination, isometric hand strength, service accuracy and forehand drive (p < 0.05). However, CG compared to PLA and CMR had no significant effect on hand-eye coordination, isometric hand strength, service accuracy and forehand drive (p > 0.05). In addition, CG and CMR enhanced significantly the explosive power of the lower body compared to PLA (p < 0.05), While there was no significant difference between CG and CMR (p > 0.05). Also, CG and CMR compared to PLA and CG compared to CMR had no significant effect on the explosive power of the upper body, backhand, and counter skills (p > 0.05). Furthermore, CG increased significantly accuracy in the service test compared to PLA (p < 0.05).

CONCLUSION

According to the results, it seems that early absorption sources of caffeine (CMR and CG) are efficient strategies for improving the specific performance of female table tennis players. However, allegedly CMR and CG have a better effect on functional and cognitive tests compared to skill tests.

Development of upper and lower extremity functional asymmetries in male and female elite youth tennis players: a longitudinal study

BACKGROUND

This longitudinal study aimed to examine the development of both upper and lower extremity functional performances, together with asymmetry magnitudes and directionality in youth tennis players.

METHODS

Dominant and non-dominant physical performance values of 90 players (53 males, 37 females) were determined yearly (with monitoring up to 3 years) using unilateral strength, power, speed and agility tests from which asymmetry magnitude percentages were calculated. Linear mixed effect models examined the development of performance values according to youth players' maturity offset, performance dominance, sex and training volume. Similarly, the development of functional asymmetry magnitudes was examined according to players' maturity offset, sex and training volume. Kappa coefficients (k) examined the consistency in directionality across test occasions.

RESULTS

Regardless of sex, the dominant and non-dominant physical performance values of every test significantly (P<0.05) improved with increasing maturity offset. No sex differences were apparent except for strength and power related tests where male players performed significantly better. Functional asymmetry magnitudes (ranging from 2.0 to 15.9%) did not significantly change with increasing maturity offset (range=-0.3-0.4% per year). Training volume was not significantly associated with the performance values and asymmetry magnitudes. The dominant upper extremity (which holds the tennis racket) consistently displayed the dominant performance value (k value: 1.00) across test occasions, which was not the case at lower extremity level (k value range: -0.28-0.31).

CONCLUSIONS

The functional asymmetry magnitudes did not change significantly with youth tennis players' maturity offset over a 3-year period.

A table tennis serve versus rally hit elicits differential hemispheric electrocortical power fluctuations

Human visuomotor control requires coordinated interhemispheric interactions to exploit the brain's functional lateralization. In right-handed individuals, the left hemisphere (right arm) is better for dynamic control and the right hemisphere (left arm) is better for impedance control. Table tennis is a game that requires precise movements of the paddle, whole body coordination, and cognitive engagement, providing an ecologically valid way to study visuomotor integration. The sport has many different types of strokes (e.g., serve, return, and rally shots), which should provide unique cortical dynamics given differences in the sensorimotor demands. The goal of this study was to determine the hemispheric specialization of table tennis serving - a sequential, self-paced, bimanual maneuver. We used time-frequency analysis, event-related potentials, and functional connectivity measures of source-localized electrocortical clusters and compared serves with other types of shots, which varied in the types of movement required, attentional focus, and other task demands. We found greater alpha (8-12 Hz) and beta (13-30 Hz) power in the right sensorimotor cortex than in the left sensorimotor cortex, and we found a greater magnitude of spectral power fluctuations in the right sensorimotor cortex for serve hits than return or rally hits, in all right-handed participants. Surprisingly, we did not find a difference in interhemispheric functional connectivity between a table tennis serve and return or rally hits, even though a serve could arguably be a more complex maneuver. Studying real-world brain dynamics of table tennis provides insight into bilateral sensorimotor integration.NEW & NOTEWORTHY We found different spectral power fluctuations in the left and right sensorimotor cortices during table tennis serves, returns, and rallies. Our findings contribute to the basic science understanding of hemispheric specialization in a real-world context.

Technical and Tactical Actions of the World's Leading Male Table Tennis Players Between 1970 and 2021

This research aimed to determine the quantitative and qualitative structure of winning systems of the world's leading male table tennis players between 1970 and 2021. The study used the Wu game analysis method, modified by the authors, which consists of observing the game from playback, identifying the winning actions of a given player, and sorting and counting the actions, depending on the accuracy of the observation. The project identified all World Championships and Olympic Games medallists, resulting in 244 men's matches being analyzed. Three time periods were considered based on the ball used, including the 38 mm celluloid ball, 40 mm celluloid ball, and 40 mm plastic ball. Differences in the level structure, depending on the observation period, were assessed using the chi-squared test of independence. The Pearson contingency coefficient was calculated, and multiple comparisons were made. The research showed that the use of combinations changed slightly with changes in ball size and material. The first three strokes were very important in all periods. However, the importance of serves as direct scoring strokes decreased. These findings may be related to changes in the size and material used for ball production. The most winning serves in the game of the top men were side-spin forehand serves, which were also used most often during 3rd-ball-attack winning combinations. The number of actions won directly with a return, and in the return-counterattack combination, accounted for, and still constitute, about 30%, with an increasing number of backhand flicks. The research also showed an increase in the use of backhand strokes compared to forehand strokes. These findings should be considered when creating basic goals in table tennis training plans.

Comparative effects of Bowen therapy and tennis ball technique on pain and functional disability in patients with thoracic myofascial pain syndrome

BACKGROUND

Thoracic myofascial pain syndrome is a clinical problem arising from the muscles and soft tissues of thoracic region, which include the mid and upper back area. Risk factors associated with myofascial pain syndrome are muscle overuse and repetitive strain, poor posture, trauma or injury, emotional and psychological stresses. The management of myofascial pain syndrome (MPS) typically involves a multidimensional approach that focuses on relieving pain, reducing muscle tension, and improving muscle function. Bowen therapy and tennis ball technique are also recommended for treating myofascial pain syndrome.

OBJECTIVE

The objective of this study was to compare the effects of Bowen therapy and tennis ball technique on pain and functional disability in patients with thoracic myofascial pain syndrome.

METHODS

It was a randomized clinical trial conducted on thirty patients. It was carried out in physiotherapy outpatient department of D.H.Q Hospital, Kasur. Non-probability convenience sampling technique was used. Data collection was done from the patients of thoracic myofascial pain syndrome by using Numeric Pain Rating Scale (NPRS) for pain and Pain Disability Questionnaire (PDQ) for functional disability. Participants were randomly allocated into two groups using computer generated random number method. Group A received Bowen therapy, and group B received tennis ball technique. Outcome measures were measured at baseline, after second week treatment session and after fourth week with three sessions in a week on alternate days. Data analysis was done by using Statistical Package for the Social Sciences (SPSS) version 26.

RESULTS

There was significant difference between the mean values of NPRS and PDQ in both groups at baseline, second week and fourth week with p value < 0.05. The results indicated that both treatments were significant but Bowen therapy is more effective treatment than tennis ball technique. Within-group difference calculated with repeated-measure ANOVA indicated that there was significant difference from pre- to post-values of both groups.

CONCLUSION

This study concluded that Bowen therapy produced statistically significant and clinically relavant results for all the outcome measures.

TRIAL REGISTRATION

(IRCT20190717044238N7).

The role of increased post-impact ball speed on plantar pressure during topspin and slice longline forehand groundstrokes in female tennis players

OBJECTIVE

Performing groundstrokes is a fundamental skill for tennis players. However, little is known about changes in plantar pressure when post-impact ball speed is increased during topspin and slice groundstrokes. The objective of the present study was to examine how elite (International Tennis Number ≤ 2) female tennis players (N = 15, mean age: 22.7 ± 7.8 years) change their plantar pressure in the dominant (equals the stroke arm) and non-dominant foot when executing topspin and slice longline forehand groundstrokes in order to increase post-impact ball speed (i.e., 80 km/h, 90 km/h, 100 km/h, vmax).

RESULTS

The repeated measures analysis of variance revealed a significant ball speed × foot dominance interaction. Post-hoc analyses showed larger mean forces during topspin compared to slice groundstrokes for the dominant foot (p ≤ .026, d ≥ 0.34) but lower values for the non-dominant foot (p ≤ .050, d ≥ 0.28). Further, with increasing post-impact ball speed, increases in mean forces in both feet during topspin could be observed but only in the dominant foot during slice groundstrokes. Varying mean forces depending on the stroke type and foot dominance imply that specific physical exercises related to these two factors are necessary to optimise plantar pressure distribution.

Development of youth tennis players: A study based on the ranking history of top ATP/WTA players worldwide and China

BACKGROUND

The top 100 ATP/WTA ranking points are a crucial indicator of entry into the high-level world of tennis players, and the number of players from a nation in this ranking reflects the overall level of their tennis. However, the growth time series characteristics of elite tennis athletes are unclear.

OBJECTIVE

This study aims to examine the historical career ranking changes of elite players and provide valuable insights for aspiring young players looking to achieve success in the sport. At the same time, it is of great significance for the efficient and sustainable cultivation of Chinese tennis players.

METHODS

Data on the rankings of 202 players were analyzed, Spearman and Pearson correlations were employed to investigate the association between ranking and time-use patterns. The variance test was utilized to compare disparities in time characteristics of the ranking, with a statistical significance level of p<0.05.

RESULTS

There was a significant correlation between the time of entering the professional tournament ranking system and the ranking, top 100 time, top 100 age, and age of starting tennis. Top 50 ATP players are earlier than those ranked 51-100. There was a significant difference between the age of starting tennis and the time to top 10 among the ATP and WTA players. Chinese female players showed no significant differences compared to their global Top 10 counterparts in terms of time-to-success characteristics.

CONCLUSION

The elite tennis players who achieve success typically start playing and competing in the sport at a young age, with professional competition often commencing around 18 years of age. Notably, these players frequently attain high rankings before reaching the age of 20. Furthermore, top 10 ATP male players tend to start tennis at an earlier age and require a shorter time to achieve a top 10 ranking compared with WTA female players.

The relative age effect among Chinese junior men's tennis players and its impact on sports performance

The relative age effect (RAE) has been the subject of many studies, but no relevant literature has discussed the phenomenon of RAE in Chinese tennis. Numerous studies have demonstrated that RAE significantly contributes to brain drain and other occurrences that create inequity. This paper analyzes the birth dates and year-end rankings of all male players (N = 2697) who participated in China's junior tennis tournaments (U12, U14, U16) between 2014 and 2019 and who were selected for China's National Junior Team in 2019 and 2020; the paper classifies the birth dates into quarters and semesters. One of the research objectives of this study is to analyze whether RAE exists in Chinese junior men's tennis and whether RAE exerts an effect on athletes' performance. Differences between the observed and expected birthdate distributions were tested using chi-square statistics, and subsequent calculations were tested using odds ratios. The study found that RAE was present in all Chinese junior male tennis sports groups (p<0.001). The percentages of athletes born in the first half of the year were 56.4% (U12), 60.4% (U14), and 60.4% (U16), and the percentages of those born in the first quarter were 34.1% (U12), 36.4% (U14), and 37.1% (U16). Athletes with birth dates closer to the beginning of the year had a higher probability of achieving excellent athletic performance as a result of RAE, whereas those who were born near the end of the year had a more difficult time achieving strong athletic performance.

The expert eye? An inter-rater comparison of elite tennis serve kinematics and performance

This study examined the reliability of expert tennis coaches/biomechanists to qualitatively assess selected features of the serve with the aid of two-dimensional (2D) video replays. Two expert high-performance coaches rated the serves of 150 male and 150 female players across three different age groups from two different camera viewing angles. Serve performance was rated across 13 variables that represented commonly investigated and coached (serve) mechanics using a 1-7 Likert rating scale. A total of 7800 ratings were performed. The reliability of the experts' ratings was assessed using a Krippendorffs alpha. Strong agreement was shown across all age groups and genders when the experts rated the overall serve score (0.727-0.924), power or speed of the serve (0.720-0.907), rhythm (0.744-0.944), quality of the trunk action (0.775-1.000), leg drive (0.731-0.959) and the likelihood of back injury (0.703-0.934). They encountered greater difficulty in consistently rating shoulder internal rotation speed (0.688-0.717). In high-performance settings, the desire for highly precise measurement and large data sets powered by new technologies, is commonplace but this study revealed that tennis experts, through the use of 2D video, can reliably rate important mechanical features of the game's most important shot, the serve.

Stroboscopic Eyewear Applied During Warm-Up Does Not Provide Additional Benefits to the Sport-Specific Reaction Speed in Highly Trained Table Tennis Athletes

PURPOSE

While long-term training with stroboscopic eyewear suggests performance-enhancing effects on visuomotor abilities, it remains unclear whether a short-term application, for example, during a warm-up, results in immediate performance gains. This study evaluated potential performance-enhancing effects of stroboscopic eyewear applied during warm-up on reaction speed that may provide athletes an edge in visuomotor-demanding sports.

METHODS

Twenty-eight international-level table tennis athletes participated in this study. Participants performed their individual 10-minute table-tennis-specific warm-up under normal visual conditions and with stroboscopic eyewear. Prior to and after the warm-up, visuomotor reaction time was assessed in a sport-specific reaction test where athletes had to return 30 table tennis balls played by a ball machine at high speed to their backhand side. Reaction time was determined as the interval between ball output and movement onset as triggered by a mechanical switch. Furthermore, the time between ball-table contact and ball-racket contact (hit time) was analyzed as an indicator of how early the athletes intercepted the ball.

RESULTS

Reaction time significantly improved following the warm-up (P < .001, ηp2=.393). However, there was no additional benefit of the stroboscopic eyewear (P = .338, ηp2=.034). No changes after the warm-up were observed for hit time (P = .246, ηp2=.055).

CONCLUSIONS

The results indicate that warm-up facilitated visuomotor reaction speed; however, stroboscopic eyewear did not provide additional positive effects when compared to a warm-up under normal visual conditions. While shutter glasses may be useful for training over longer periods, short-term positive effects were not supported in this study.

Effects of 4 Weeks of Variability Training on Forehand Approach Precision and Velocity in Recreational Tennis Players

This study aims to analyze the effects of a training program based on practice variability on the speed and accuracy of the tennis forehand approach to the net shot. The study sample consisted of 35 players of both genders, 22 men and 13 women (age 44 ± 10.9 years, height 1.73 ± 0.8 cm, and weight 74.7 ± 8.4 kg). Players were randomly distributed into two groups (control group = 18 and experimental group = 17). Both training groups worked a total volume of 4 weeks, seven sessions, and 15 min per session of forehand approach shot. Control group performed traditional training while experimental group trained with variability using wristband weights. The data obtained showed a large Group × Time interaction in the accuracy of the forehand approach shot, F(1, 16) = 28.034, p < .001, η2 = .637. Only the experimental group increased significantly in the accuracy after the program (51.4%, effect size = 1.3, p < .001), while no changes were achieved regarding hitting speed (1.2%, effect size = 0.12, p = .62). The control group did not improve in any of the tested variables. These results indicate that variability of training using wrist weights is a valid option to improve forehand approach shot accuracy in recreational-level players. Although stroke speed was not increased, this type of training may be interesting as accuracy and technical control is commonly the main goal of training at this level.

Change-of-Direction Speed Assessments and Testing Procedures in Tennis: A Systematic Review

ABSTRACT

Schneider, C, Rothschild, J, and Uthoff, A. Change-of-direction speed assessments and testing procedures in tennis: a systematic review. J Strength Cond Res 37(9): 1888-1895, 2023-Change-of-direction speed (CODS) plays an essential role in tennis match play, and CODS performance is, therefore, commonly assessed and monitored in tennis players. Thus, the aim of this systematic review was to describe test characteristics, performance metrics, test-retest reliability, construct validity, and test outcomes of tests that are used to assess CODS in tennis players. A literature search conducted on PubMed and SPORTDiscus yielded 563 results. After applying the eligibility criteria, a total of 27 studies were included in the present review. Ten unique CODS tests were identified. 505 test variations were most frequently used across all studies, and total time required to complete the test was the predominant performance metric investigated. Intrasession test-retest reliability ranged from "moderate" to "excellent." Intersession test-retest reliability as well as the effects of tennis performance, sex, and age on CODS performance were unclear given the subject demographics and the limited number of studies that investigated these aspects. In conclusion, most studies included CODS tests that exhibit longer COD entry and total distances but similar COD angles to those seen during tennis match play. All CODS tests have at least "moderate" intrasession test-retest reliability. However, to improve CODS assessment methods and to increase our current understanding of CODS performance in tennis players, there is a need to conduct more research on the intersession test-retest reliability, construct validity, and the effects of sex, age, and tennis performance and to investigate other performance metrics that might provide additional insights into CODS (e.g., phase-specific performance variables).

Effects of Yoga Training Applied with Telerehabilitation on Core Stabilization and Physical Fitness in Junior Tennis Players: A Randomized Controlled Trial

INTRODUCTION

This study aimed to investigate the effects of yoga training applied with telerehabilitation on core stability, and strength, balance, flexibility, upper extremity stability, body awareness, and quality of life in tennis players aged 6-18 years.

METHODS

Forty tennis players were randomly divided into two groups to participate in this study. The control group (n = 20) continued tennis training and was informed about the importance of the core region. The yoga group (n = 20) received yoga training with telerehabilitation 2 days a week for 8 weeks. Athletes were evaluated with sport-specific core muscle strength and stability tests, the back scratch test, the sit and reach test, the flamingo balance test, the y-balance test (lower quarter), the upper extremity closed kinetic chain stability test, the SF-36, and body awareness questionnaires. Measurements have been done in the tennis club before and after the 8 weeks of training.

RESULTS

A significant increase was determined in core strength and stability, sit and reach, back scratch test, upper extremity stability, and body awareness questionnaire in the yoga group (p < 0.001). Flamingo and Y balance test results were significant (p < 0.002). Positive improvements were found in SF-36s energy-fatigue level, mental well-being, social function (p < 0.042), pain (p < 0.005), and general health (p < 0.001). A significant increase was observed in the core strength measurement mean score in the control group (p < 0.018). Sit and reach test, flamingo test, and body awareness questionnaire were found to be significant after the intervention (p < 0.001). Significant improvements were found in the pain (p < 0.042), and mental well-being (p < 0.001) sub-parameters of the SF-36.

CONCLUSION

In the study, it was concluded that yoga training applied with telerehabilitation in tennis players aged 6-18 has a positive effect on core strength, and stabilization, physical fitness parameters, quality of life, and body awareness.

Einleitung

Mit dieser Studie sollten die Auswirkungen von Yogatraining in Verbindung mit Telerehabilitation auf Rumpfstabilität, Kraft, Gleichgewicht, Flexibilität, Stabilität der oberen Extremität, Körperwahrnehmung und Lebensqualität bei Tennisspielern im Alter von 6 bis 18 Jahren untersucht werden.

Methoden

Vierzig Tennisspieler wurden randomisiert in zwei Gruppen aufgeteilt und nahmen an der Studie teil. Die Kontrollgruppe (n = 20) führte das Tennistraining fort und wurde über die Bedeutung der Rumpfregion aufgeklärt. Die Yoga-Gruppe (n = 20) erhielt an 2 Tagen pro Woche über 8 Wochen ein Yogatraining mittels Telerehabilitation. Die Sportler wurden mittels sportartspezifischer Tests zur Kraft und Stabilität der Rumpfmuskulatur, dem Back-Scratch-Test, dem Sit-and-Reach-Test, dem Flamingo-Balance-Test, dem Y-Balance-Test (unteres Viertel), dem Closed Kinetic Chain Upper Extremity Stability Test sowie dem SF-36 und dem Fragebogen zur Körperwahrnehmung beurteilt. Die Messungen wurden im Tennisclub vor und nach dem 8-wöchigen Training durchgeführt.

Ergebnisse

In der Yoga-Gruppe wurde ein signifikanter Anstieg der Rumpfkraft und -stabilität sowie im Sit-and-Reach-Test, Back-Scratch-Test, der Stabilität der oberen Extremität und beim Fragebogen zur Körperwahrnehmung festgestellt (p < 0,001). Die Ergebnisse des Flamingo-Balance-Tests und des Y-Balance-Tests fielen signifikant aus (p < 0,002). Verbesserungen zeigten sich beim SF-36-Score für Energieverlust und Erschöpfung, psychisches Wohlbefinden, soziale Funktion (p < 0,042), Schmerzen (p < 0,005) und allgemeine Gesundheit (p < 0,001). In der Kontrollgruppe war ein signifikanter Anstieg des mittleren Scores der Rumpfkraftmessung zu beobachten (p < 0,018). Der Sit-and-Reach-Test, der Flamingo-Test und der Fragebogen zur Körperwahrnehmung fielen nach der Intervention signifikant aus (p < 0,001). Bei den Unterparametern Schmerz und psychisches Wohlbefinden des SF-36 wurden signifikante Verbesserungen festgestellt (p < 0,042 bzw. p < 0,001).

Diskussion/Schlussfolgerung

Die Studie kam zu der Schlussfolgerung, dass Yoga-Training bei Anwendung mittels Telerehabilitation bei Tennisspielern im Alter von 6 bis 18 Jahren einen positiven Effekt auf die Rumpfkraft und -stabilisierung, die Parameter der körperlichen Fitness, die Lebensqualität und die Körperwahrnehmung hat.

Cold-water immersion and whole-body cryotherapy attenuate muscle soreness during 3 days of match-like tennis protocol

PURPOSE

This study aimed to investigate the effect of whole-body cryotherapy (WBC), cold-water immersion (CWI) and passive recovery (PAS) on tennis recovery.

METHODS

Thirteen competitive male tennis players completed three consecutive match-like tennis protocols, followed by recovery (WBC, CWI, PAS) in a crossover design. Five tennis drills and serves were performed using a ball machine to standardize the fatiguing protocol. Maximal voluntary contraction (MVC) peak torque, creatine kinase activity (CK), muscle soreness, ball accuracy and velocity together with voluntary activation, low- and high-frequency torque and EMG activity were recorded before each protocol and 24 h following the third protocol.

RESULTS

MVC peak torque (- 7.7 ± 11.3%; p = 0.001) and the high- to low-frequency torque ratio (- 10.0 ± 25.8%; p < 0.05) decreased on Day 1 but returned to baseline on Day 2, Day 3 and Day 4 (p = 0.052, all p > 0.06). The CK activity slightly increased from 161.0 ± 100.2 to 226.0 ± 106.7 UA L-1 on Day 1 (p = 0.001) and stayed at this level (p = 0.016) across days with no differences between recovery interventions. Muscle soreness increased across days with PAS recovery (p = 0.005), while no main effect of time was neither observed with WBC nor CWI (all p > 0.292). The technical performance was maintained across protocols with WBC and PAS, while it increased for CWI on Day 3 vs Day 1 (p = 0.017).

CONCLUSION

Our 1.5-h tennis protocol led to mild muscle damage, though neither the neuromuscular function nor the tennis performance was altered due to accumulated workload induced by consecutive tennis protocols. The muscle soreness resulting from tennis protocols was similarly alleviated by both CWI and WBC.

TRIAL REGISTRATION

IRB No. 2017-A02255-48, 12/05/2017.

Biomechanical analyses of different serve and groundstroke techniques in tennis: A systematic scoping review

This systematic scoping review aims to summarize findings regarding kinetic, kinematic, and electromyographic analyses of different characteristics (i.e., type/direction and stance style) of the tennis serve and groundstroke. A systematic search of the literature was performed on the databases PubMed, Web of Science, and SportDiscus from their inception date till May 2023. A descriptive analysis of results was conducted. The literature search identified a total of N = 899 records, 23 of which met the inclusion criteria and were analysed in this review. A total of 229 participants aged 18 to 62 years participated in the studies. The studies revealed varying results, ranging from significantly lower/higher values to no significant differences between serve/groundstroke characteristics. These inconsistent results may most likely be attributed to discrepancies in the methodological approach such as players' age (18-62 years), sex (i.e., men only or both sexes), and performance level (i.e., recreational, intermediate, or advanced) as well as the applied measurement devices (i.e., force plate or pressure-detecting insoles; motion capture system, high-speed video recordings, or IMU sensors) and used outcomes (i.e., measured or estimated force etc.). Future research is needed to provide a comprehensive biomechanical analysis of different serve/groundstroke characteristics. Specifically, it is recommended to compare different tennis serve and groundstroke types/directions and stance styles in female and male age-matched players with diverging performance levels (i.e., recreational, intermediate, advanced) using combined (i.e., kinetic, kinematic, and electromyographic) biomechanical analysis.

Ankle proprioception in table tennis players: Expertise and sport-specific dual task effects

OBJECTIVES

To compare ankle proprioception between professional adolescent table tennis players at national and regional levels and age-matched non-athletes, and, in a nominally upper-limb sport, to explore the relationships between single- and dual-task ankle proprioception, years of training and sport-specific performance.

DESIGN

Cross-sectional observational study.

METHODS

Fifty-five participants (29 professional adolescent table tennis players and 26 non-athletic peers) volunteered. Ankle proprioception was first assessed using the active movement extent discrimination apparatus (AMEDA-single) for all; yet only the players were then re-assessed while executing a secondary ball-hitting task (AMEDA-dual). The mean Area Under the Receiver Operating Characteristic Curve was calculated as the proprioceptive score, and years of training and hitting rate were recorded.

RESULTS

National-level players had significantly better ankle proprioception as shown by higher AMEDA-single scores than the other groups (all p < 0.05). Ankle proprioceptive performance was significantly impaired while ball-hitting (F1,28 = 58.89, p ≤ 0.001, ηp2 = 0.69). National-level players outperformed the regional-level significantly on the AMEDA-dual task (F1,27 = 21.4, p ≤ 0.001, ηp2 = 0.44). Further, ankle proprioceptive performance was related to expertise, in that both AMEDA-single and AMEDA-dual proprioceptive scores were correlated with years of training and ball-hitting rate (r from 0.40 to 0.54, all p < 0.05).

CONCLUSIONS

Ankle proprioception is a promising measure that may be used to identify different ability levels among adolescent table tennis players. Superior ankle proprioception may arise from rigorous training and contribute to stroke accuracy. Dual-task proprioceptive assessment suggests how elite table tennis players perform differently from lower-ranked players in complex and changeable sports circumstances.

Correlation of Glenohumeral Internal Rotation Deficit With Shoulder Pain in Elite Table Tennis Players

OBJECTIVES

The aims of the study were (1) to investigate glenohumeral internal rotation deficit (a difference in internal rotation of 15.6 degrees or more between dominant and nondominant shoulders) and its correlation with self-reported shoulder pain in table tennis players and (2) to find the optimal cutoff point for the difference in the internal rotation range of motion between dominant and nondominant shoulders of self-reported shoulder pain.

DESIGN

The internal rotation range of motion of both shoulders of 46 table tennis players was measured in the supine and side-lying positions, and the external rotation range of motion was measured in the supine position.

RESULTS

Significant differences existed in internal rotation range of motion between the two sides in the supine ( z = 6.53, P < 0.001) and side-lying positions ( z = 5.67, P < 0.001). Self-reported shoulder pain was associated with glenohumeral internal rotation deficit (odds ratio = 6.86, 95% confidence interval = 1.752-26.832, P = 0.006). The cutoff points for the difference in internal rotation range of motion between the sides of self-reported shoulder pain were 17.9 degrees in the supine position and 11.1 degrees in the side-lying position.

CONCLUSIONS

Table tennis players exhibited glenohumeral internal rotation deficit. There was a correlation between glenohumeral internal rotation deficit and self-reported shoulder pain in the past year; therefore, glenohumeral internal rotation deficit may be a risk factor for shoulder pain in table tennis players.

Elite male table tennis matches diagnosis using SHAP and a hybrid LSTM-BPNN algorithm

This study adopts a new approach, SHapley Additive exPlanation (SHAP), to diagnose the table tennis matches based on a hybrid algorithm, namely Long Short-Term Memory-Back Propagation Neural Network (LSTM-BPNN). 100 male singles competitions (8535 rallies) from 2019 to 2022 are analyzed by a hybrid technical-tactical analysis theory, which hybridizes the double three-phase and four-phase evaluation theories. A k-means cluster analysis is conducted to classify 59 players' winning rates into three levels (high, medium, and low). The results show that LSTM-BPNN has excellent performance (MSE = 0.000355, MAE = 0.014237, RMSE = 0.018853, and [Formula: see text] = 0.988311) compared with six typical artificial intelligence algorithms. Using LSTM-BPNN to calculate the SHAP value of each feature, the global results find that the receive-attack and serve-attack phases of the ending match have essential impacts on the mutual winning probabilities. Finally, case applications show that the SHAP can directly obtain each feature importance on one or more matches, which is more objective and reliable than the traditional simulation method. This research explores an innovative way to understand and analyze matches, and these results have implications for the performance analysis of table tennis and related racket sports.

Perceived self-efficacy by Under-10 tennis players when scaling the equipment and play area

The modification of child-sports aims to develop an optimal learning environment that facilitates the emergence of desirable psychological outcomes (e.g., self-efficacy). The aim of the study was to assess the effect of reducing net height and court size on self-efficacy and shot-efficacy of U-10 tennis players in a real-game context. Twenty U-10 tennis players (M = 9.46, SD = 0.66 years of age; M = 3.65, SD = 1.53 years of tennis experience) played two round-robin tournaments one week apart in the same order and schedule. The first tournament was played under the International Tennis Federation's Tennis 10s regulation at green stage (GT). Afterwards, the modified tournament (MT) was played with the same regulation GT, however, net height (0.91 m-0.80 m) and court size (23.77 m × 8.23 m-18.00 m × 8.23 m) were reduced. Results accomplished using Bayesian and Frequentist inferences showed an increase in players' self-efficacy when serving in MT than GT (BF10 = 4.796; δ = -0.576; and p = .011). This is increase may be due to a reduction in their serving faults in MT (BF10 = 6.169; δ = -0.591; and p = .010). Therefore, reducing net height and court size enhances the serve performance and self-efficacy and thus promotes positive tennis experiences.

Influence of Visual and Haptic Cues on Motor Learning: Insights from Tennis Skill Acquisition in Children

Underdevelopment of cognitive abilities in children, such as memory and attention, may make the use of verbal instructions difficult for learning new motor skills. The objective of this study was to evaluate whether visual and haptic cues which emphasize certain instructions facilitate skill acquisition in young tennis players. Twenty children were distributed in 2 groups: experimental (EXP) and control (CON). EXP received a racket with visual and haptic cues while CON trained with a classic racket. The task consisted of playing 30 consecutive forehands during a pretest and 16 weeks post-intervention. EXP displayed a larger improvement both in their technique (better ready position, more balls hit in front and to the side of the body) and in their performance (more points scored), highlighting the positive impact of visual and haptic cues during the early stage of motor learning.

Influence of Successive Wheelchair Tennis Matches on Handgrip Strength in High-Level Male Players

The purpose of this study was to examine the effects on upper strength in high-level male players playing four successive wheelchair tennis (WT) matches. Eight international WT players took part in a competition, playing one match per day over four consecutive tournament days. Before and after the match, the maximal isometric handgrip strength was measured on the dominant and non-dominant hand. Additionally, each player was equipped with one radiofrequency and IMU device on their wheelchair to control his activity profile (distance). The results showed significant differences between successive matches, with decreasing dominant handgrip strength (p = 0.02, η² = 0.043), and there was a significant interaction between successive matches and the accumulated distance (p = 0.013, η² = 0.049). The pre- and post-match strength values of the dominant hand decreased throughout the matches over a number of days, and post hoc analysis showed differences between the first and fourth matches only in pre-match strength (49.06 ± 6.96 vs. 45.94 ± 7.1; p = 0.045; ES: 1.04) but not in the non-dominant hand. Successive matches caused a decrease in the strength values of the WT players, mainly in the dominant hand. These results should be taken into account in the recovery and prevention of injuries in competitions with successive matches.