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).

Tool to assess the groundstroke technique of preadolescent tennis players.

Objective: In this study, we develop a tool that can be used by tennis coaches to evaluate the groundstroke (forehand and backhand) technique of preadolescent tennis players. Methods: The participants of the study were 60 children (30 males and 30 females) aged 10-12 years, with at least two years of training in tennis. The Groundstroke Correction Checklist (GCC) was translated into Turkish by using a blind procedure. The Turkish translation was then evaluated by 15 coaches of the Turkish Tennis Federation who had at least a level-3 coaching license and more than five years of coaching experience. The technical components related to technique in the checklist were labeled as unimportant, important, and very important. Following this, the GCC was converted into a Groundstroke Technique Assessment Test Tool (GTATT) by a selection committee consisting of three experts, and its reliability and validity were assessed by using it in the field. Spearman's correlation was used to analyze the correlation (test-r test) between the technical evaluation scores assigned to the players by the tennis coaches based on the GTATT in the first and second weeks. Intra- and inter-rater reliability was used to analyze the overall scores of technical evaluations in the first and second weeks to assess the reliability of the scale used. We determined each player's number of years of playing experience (TPY), technical evaluation (TE), international tennis-level test score (ITN), I-cord classification order (ICCO), and the number of games won (GW) in a tournament organized among themselves and evaluated the correlations among these parameters by using Spearman's correlation analysis. Conclusion: A statistically high and significant correlation was observed between the technical evaluations of the players' forehand and backhand groundstrokes by the tennis coaches by using the GTATT in the first and second weeks (r > .90, p < .01). The analysis of the intra- and inter-rater reliability of the GTATT yielded excellent agreement between the technical observations of the three coaches of the players' forehand and backhand strokes in the first and second weeks.

Epidemiology of Musculoskeletal Injuries in Tennis Players During the French Open Grand Slam Tournament From 2011 to 2022.

Background: The epidemiology of musculoskeletal injuries at the Australian Open, Wimbledon, and US Open tennis tournaments has been investigated in recent studies; however, there is no published literature on the incidence of musculoskeletal injuries at the French Open. Purpose: To describe the incidence, location, and type of musculoskeletal injuries in tennis players during the French Open tournament from 2011 to 2022. Study Design: Descriptive epidemiology study. Methods: A review was performed of all injuries documented by a multidisciplinary medical team during the French Open from 2011 to 2022. All musculoskeletal injuries that occurred during the main draw of the female and male singles or doubles matches were included. Descriptive statistics were used to summarize the data. Injury locations were grouped into regions as well as into upper limb, trunk, and lower limb. Results: In total, there were 750 injuries in 687 tennis players, resulting in a mean of 62.5 injuries per tournament; however, there were no obvious trends in injury incidence over the time frame evaluated. The number of injuries in female and male players was similar (392 vs 358, respectively). The most common injury regions were the thigh/hip/pelvis (n = 156), ankle/foot (n = 114), and spine (n = 103). The most common injury types were muscle-related (n = 244), tendon-related (n = 207), and joint-related (n = 163), and the most affected muscles were the adductors (n = 45), rectus abdominis (n = 38), and lumbar muscles (n = 25). Conclusion: Over the 12-year period from 2011 to 2022 female and male players experienced similar numbers of musculoskeletal injuries, with most injuries occurring in the lower limbs compared with the upper limbs and trunk.

Defining tennis elbow characteristics - The assessment of magnetic resonance imaging defined tendon pathology in an asymptomatic population.

Background: This radiological study aims to assess the prevalence of lateral elbow pathology in an asymptomatic population using 3.0T magnetic resonance imaging (MRI). Methods: Bilateral elbow MRI was undertaken in 30 asymptomatic volunteers. Exclusion criteria included elbow pain within 3 months, elbow trauma or previous diagnosis of lateral epicondylar tendinopathy. Baseline patient-reported outcome measures were recorded along with age and body mass index (BMI). Two musculoskeletal radiologists independently graded the degree of abnormality at the common extensor tendon. Results: Thirty volunteers were categorised according to age; 35-44 (n = 10), 45-54 (n = 11), and 55-65 (n = 9) with a 1:1 male-to-female ratio. Radiological evidence of tendon abnormality was found in 37% of volunteers. The proportion with abnormal findings increased with age; 35-44 (10%), 45-54 (36%), 55-65 (67%) and BMI; 18-24.9 (23%), 25-29.9 (43%), > 30 (67%). Changes were generally 'mild' or 'moderate', with a single volunteer showing 'severe' pathology. Kappa for the radiographic agreement was 0.91 (0.83-0.98). Discussion: This study has demonstrated MRI findings suggestive of pathology at the common extensor tendon to be prevalent in an asymptomatic population, increasing with age and BMI. This draws into question the diagnostic and prognostic value of MRI imaging in lateral epicondylar tendinopathy, especially in older patients.

Table tennis experience enhances motor control in older adults: Insights into sensorimotor-related cortical connectivity.

Background: Motor control declines with age and requires effective connectivity between the sensorimotor cortex and the primary motor cortex (M1). Despite research indicating that physical exercise can improve motor control in older individuals the effect of physical exercise on neural connectivity in older adults remains to be elucidated. Methods: Older adults with experience in table tennis and fit aerobics and individuals without such experience for comparison were recruited for the study. Differences in motor control were assessed using the stop-signal task. The impact of exercise experience on DLPFC-M1 and pre-SMA-M1 neural connectivity was assessed with transcranial magnetic stimulation. Varied time intervals (short and long term) and stimulus intensities (subthreshold and suprathreshold) were used to explore neural connectivity across pathways. Results: The present study showed that behavioral iexpression of the table tennis group was significantly better than the other two groups;The facilitatory regulation of preSMA-M1 in all groups is negatively correlated with SSRT. Regulatory efficiency was highest in the table tennis group. Only the neural network regulatory ability of the Table Tennis group showed a negative correlation with SSRT; Inhibitory regulation of DLPFC-M1 was positively correlated with SSRT; this effect was most robust in the table tennis group. Conclusion: The preliminary findings of this study suggest that table tennis exercise may enhance the motor system regulated by neural networks and stabilize inhibitory regulation of DLPFC-M1, thereby affecting motor control in older adults.

Long-term table tennis training alters dynamic functional connectivity and white matter microstructure in large scale brain regions.

Table tennis training has been employed as an exercise treatment to enhance cognitive brain functioning in patients with mental illnesses. However, research on its underlying mechanisms remains limited. In this study, we investigated functional and structural changes in large-scale brain regions between 20 table tennis players (TTPs) and 21 healthy controls (HCs) using 7-Tesla magnetic resonance imaging (MRI) techniques. Compared with those of HCs, TTPs exhibited significantly greater anisotropy fraction (FA) and axial diffusivity (AD) values in multiple fiber tracts. We used the locations with the most significant structural changes in white matter as the seed areas and then compared static and dynamic functional connectivity (sFC and dFC). Brodmann 11, located in the orbitofrontal cortex, showed altered dFC values to large-scale brain regions, such as the occipital lobe, thalamus, and cerebellar hemispheres, in TTPs. Brodmann 48, located in the temporal lobe, showed altered dFC to the parietal lobe, frontal lobe, cerebellum, and occipital lobe. Furthermore, the AD values of the forceps minor (Fmi) and right anterior thalamic radiations (ATRs) were negatively correlated with useful field of view (UFOV) test scores in TTPs. Our results suggest that table tennis players exhibit a unique pattern of dynamic neural activity; this provides evidence for potential mechanisms through which table tennis interventions can enhance attention and other cognitive functions.

Reliability and Usefulness of YouTube as a Source of Informative Media for Arthroscopic Tennis Elbow Surgery: A Systematic Review of the Published Videos.

Aims and Objectives: Over the last decade, YouTube has been extensively used as a learning tool for both physicians and patients, but the reliability of this information remains questionable. The purpose of this study was to look for the reliability and quality of videos on tennis elbow arthroscopy on YouTube. Materials and Methods: We used three search terms on YouTube "tennis elbow arthroscopic surgery," "Arthroscopic ECRB release," and "Arthroscopic debridement for tennis elbow," and screened the first 50 videos according to popularity. The videos were included from 2009 to date. Only videos in the English language were included. Repeated videos and videos without sound were excluded. A total of 74 videos were selected for this study and reliability was checked with DISCERN and journal of the American medical association (JAMA) scores. The quality was assessed with the Global Quality Score Criteria (GQSC) score and TEARS (a novel score). Popularity was tested with the video power index (VPI). A pilot study was conducted using 20 videos to validate the TEARS score. Results: In the pilot study, TEARS showed results in accordance with other scores used. The average number of views was 41,644.97, and the average duration was 5.03 ± 3.39 years. The mean value of DISCERN and JAMA was found to be 21.47 ± 6.28 and 1.05 ± 0.92, respectively. GQSC, TEARS, and VPI were found to be 1.70 ± 0.82, 4.17 ± 2.62, and 769,936.9 ± 6,538,851.37. Conclusion: Most of the videos were educational and physicians were targeted. The USA was the major contributor to such videos. The reliability and quality of these videos were found to be of poor quality. The video popularity was however found to be relatively high. The inter-observer reliability was good. Based on the findings, we conclude that the videos are not reliable and could not be used for learning.

Changes in Body Composition and Physical Performance after a Six-Week International Tour in Young Chilean Female Tennis Players.

Junior tennis players travel a lot to play tennis tournaments; this causes them to spend a lot of time away from their homes and disrupts their training, which could reduce their performance and increase the risk of injury. The purpose of this study was to analyze the changes in physical performance and body composition after a six-week international tour in young Chilean female tennis players. Thirty young female tennis players (15.4 ± 0.6) participated in this study. Body weight, skinfolds, and perimeters were measured. Body fat percentage (BFP) and skeletal muscle mass (SMM) were calculated. For physical performance, 5 m sprint, the 505 with stationary start test (505 test), the pro-agility test, countermovement jump (CMJ), and medicine ball throw (MBT) were evaluated. The results show a significant increase in BFP and decrease in SMM (p < 0.01; d = -0.18 and 0.19, respectively). In terms of physical performance, 5 m sprint, the 505 test (p < 0.01; d = -0.95 and -0.95, respectively), CMJ, MBT, and HJ significantly decreased post-tour (p < 0.05; d = 0.96, 0.89 and 0.47, respectively). We conclude that, after a six-week international tour, there were changes in body composition and a significant decrease in 5 m sprint, the 505 test, CMJ, and MBT.

Does Playing Tennis with a Low-Compression Ball Effect Psychophysiological Responses and Match Characteristics in Recreational Adult Players?

This study aimed to compare the effects of playing tennis using low-compression balls (Lc-Balls) and standard balls (St-Balls) on psychophysiological responses and match characteristics among recreational adult tennis players. Participants (N = 24; age: 20.5 ± 1.3 years) were randomly matched to play two singles matches over three sets: one match was played with a Lc-Ball and one match was played with a St-Ball, resulting in twenty-four matches. Heart-rate responses and match characteristics were assessed during each match. Post-match measures included retrospective assessments of perceived exertion, ratings of enjoyment towards physical activity, and ratings of mental effort and mood. Results showed higher psychophysiological responses and more intensive play during the game when playing with the Lc-Ball (p ≤ 0.05, d values ranging from 0.24 to 1.93 [small to very large effect]). Further, playing with a Lc-Ball related to reporting a lower rating of perceived exertion (p = 0.00, d = 0.90 [moderate effect]) and greater physical enjoyment (p = 0.00, d = 1.73 [large effect]). Playing with the St-Ball was associated with higher unpleasant mood responses including depression, tension, anger, and fatigue. In conclusion, the results suggest that using the Lc-Ball may lead to better match performance with higher enjoyment in the tennis match-play in recreational adult tennis players.

Does Motor Imagery Training Improve Service Performance in Tennis Players? A Systematic Review and Meta-Analysis.

Motor imagery training is a common mental strategy used by tennis players and coaches to improve learning and performance; however, the effect of motor imagery training on service performance in tennis players is questionable. This review aims to consolidate existing research regarding the effects of motor imagery training on the service performance of tennis players. A systematic search was conducted following the PRISMA guidelines, using PubMed, Web of Science, SCOPUS, and SPORTDiscus to identify articles published until December 2023. Eligible studies comprised controlled trials that investigated the impact of motor imagery on service performance outcomes in tennis players. The methodological quality of individual studies was assessed using the Cochrane RoB-2 and ROBINS-I tools. GRADE was applied to assess the certainty of the evidence. Nine trials including 548 participants met the inclusion criteria. The results indicated that motor imagery training improved service accuracy and technique but did not affect service speed or return accuracy in tennis players. In conclusion, the certainty of the evidence that motor imagery training may be effective in improving service accuracy and technique in tennis players is low to very low. However, more experimental work is needed to obtain stronger conclusions.

Mechanisms of Action Anticipation in Table Tennis Players: A Multivoxel Pattern Analysis Study.

An exceptional ability to accurately anticipate an opponent's action is paramount for competitive athletes and highlights their experiential mastery. Despite conventional associations of action observation with specific brain regions, neuroimaging discrepancies persist. To explore the brain regions and neural mechanisms undergirding action anticipation, we compared distinct brain activation patterns involved in table tennis serve anticipation of expert table tennis athletes vs. non-experts by using both univariate analysis and multivoxel pattern analysis (MVPA). We collected functional magnetic resonance imaging data from 29 table tennis experts and 34 non-experts as they pressed a button to predict the trajectory of a ball in a table tennis serve video truncated at the moment of racket-ball contact vs. pressing any button while viewing a static image of the first video frame. MVPA was applied to assess whether it could accurately differentiate experts from non-experts. MVPA results indicated moderate accuracy (90.48%) for differentiating experts from non-experts. Brain regions contributing most to the differentiation included the left cerebellum, the vermis, the right middle temporal pole, the inferior parietal cortex, the bilateral paracentral lobule, and the left supplementary motor area. The findings suggest that brain regions associated with cognitive conflict monitoring and motor cognition contribute to the action anticipation ability of expert table tennis players.

Evaluation of the efficiency of an ultrasound-supported infiltration technique in patients with tennis elbow applying the ITEC medical device: a multicenter study.

Background: The treatment of lateral epicondylitis remains unsatisfactory in certain cases. The aim of this study is to investigate the efficiency of an ultrasound-guided infiltration combined with fenestration of the extensor tendon postulating a 50% reduction in pain on exertion within 6 months. Methods: In a prospective, nonrandomized, multicenter study design, 68 patients with chronic lateral epicondylitis and symptoms lasted for at least 6 weeks were included. Each hospital has been assigned for Traumeel (A), autologous whole blood (B), or dextrose (C) in advance. Preinterventional, 6 weeks, 12 weeks, 6 and 12 months after infiltration, patient-related outcome parameter, and dorsal wrist extension strength were documented. Preinterventional (obligate) and after 6 months (optional) radiological evaluation (magnetic resonance imaging) was performed. Results: The Visual Analog Scale showed a significant reduction after 6 months in all groups (A. 4.8-2.5, B. 6.2-2.3, C. 5.8-2.4). Similar results could be observed with Subjective elbow value, Disabilities of Arm, Shoulder, and Hand Score, Mayo Elbow Performance Score, and Patient Rated Tennis Elbow Evaluation. The loss of strength could be completely compensated after about 6 months. Magnetic resonance imaging did not fully reflect clinical convalescence. Re-infiltrations were sometimes necessary for final reduction of symptoms (A = 11, B = 8, C = 4). Switching to surgical intervention was most frequently observed in group C (A = 2, B = 1, C = 5). In 14.5% of the cases, no improvement of the symptoms could be achieved with this method. Conclusion: The primary hypothesis of a significant long-term pain reduction of at least 50% could be achieved regardless of the medication chosen.

A Novel Surgical Technique for the Reconstruction of Chronic Tennis Leg Injury.

Tennis leg, a rupture of the medial head of the gastrocnemius muscle at the musculotendinous junction (MTJ), is common, particularly among middle-aged sports enthusiasts. While acute cases usually resolve with conservative care, optimal surgical strategies for the treatment of chronic injuries remain undefined. This study reviews the current literature and details the successful operative treatment of a 37-year-old male with a 12-month history of tennis leg, employing a novel reverse flap technique from the MTJ's aponeurosis and augmented by a facia lata allograft.

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.

Exploring the feasibility and acceptance of an optimised physiotherapy approach for lateral elbow tendinopathy: a qualitative investigation within the OPTimisE trial.

OBJECTIVES: To explore the acceptability of an optimised physiotherapy (OPTimisE) intervention for people with lateral elbow tendinopathy (LET) and feasibility of comparing it to usual care in a randomised controlled trial. DESIGN: Semistructured interviews, analysed using thematic analysis and mapped onto the COM-B model of behaviour change. SETTING: Conducted as part of the OPTimisE Pilot & Feasibility randomised controlled trial within physiotherapy departments in the United Kingdom National Health Service. PARTICIPANTS: 17 patients with LET (purposively sampled to provide representativeness based on age, sex, ethnicity, deprivation index and treatment allocation) and all 8 physiotherapists involved as treating clinicians or site principal investigators. RESULTS: Four themes were identified. First, participants reported the OPTimisE intervention as acceptable. Second, differences between the OPTimisE intervention and usual care were identified, including the use of an orthosis, holistic advice/education including modifiable risk factors, forearm stretches, general upper body strengthening and a more prescriptive exercise-dosing regimen. Third, participants provided feedback related to the trial resources, which were viewed positively, but identified language translation as a need. Fourth, feedback related to trial processes identified the need for changes to outcome collection and reduction of administrative burden. From the perspective of adopting the OPTimisE intervention, we found evidence that participants were able to change their behaviour. Considering the findings through the lens of the COM-B model, the intervention is likely to be deliverable in practice and the trial can be delivered at scale with some additional support for physiotherapists. CONCLUSIONS: Overall, the OPTimisE intervention was found to be different to usual care and acceptable to patients and physiotherapists. The study highlighted the need to refine trial processes and resources prior to a full-scale trial, to reduce administrative burden, increase support for physiotherapists, improve return rate of outcome questionnaires and provide language translation. TRIAL REGISTRATION NUMBER: ISRCTN database 19 July 2021. https://www.isrctn.com/ISRCTN64444585.

Characteristics of Resting-State Electroencephalogram Network in α-Band of Table Tennis Athletes.

BACKGROUND: Table tennis athletes have been extensively studied for their cognitive processing advantages and brain plasticity. However, limited research has focused on the resting-state function of their brains. This study aims to investigate the network characteristics of the resting-state electroencephalogram in table tennis athletes and identify specific brain network biomarkers. METHODS: A total of 48 healthy right-handed college students participated in this study, including 24 table tennis athletes and 24 controls with no exercise experience. Electroencephalogram data were collected using a 64-conductive active electrode system during eyes-closed resting conditions. The analysis involved examining the average power spectral density and constructing brain functional networks using the weighted phase-lag index. Network topological characteristics were then calculated. RESULTS: The results revealed that table tennis athletes exhibited significantly higher average power spectral density in the α band compared to the control group. Moreover, athletes not only demonstrated stronger functional connections, but they also exhibited enhanced transmission efficiency in the brain network, particularly at the local level. Additionally, a lateralization effect was observed, with more potent interconnected hubs identified in the left hemisphere of the athletes' brain. CONCLUSIONS: Our findings imply that the α band may be uniquely associated with table tennis athletes and their motor skills. The brain network characteristics of athletes during the resting state are worth further attention to gain a better understanding of adaptability of and changes in their brains during training and competition.

Effect of conscious conflict on the subliminal perception of table tennis players: from the electrophysiological evidence of ERP.

Table tennis athletes possess a strong ability to identify subliminal stimuli and perform better (faster response time and lower error rate) than non-athletes in the subliminal priming experiment when the prime is congruent with the target stimulus. However, whether athletes perform equally well in the presence of interference stimuli around the target stimulus remains unknown. Effect of conflicts triggered by consciously perceived flanker stimuli on the subliminal perception were assessed using an experimental paradigm featuring flankers and a masked prime. Both the athlete and non-athlete groups exhibited a significant priming effect when target and flanker were congruent. The athlete group also showed a considerable priming effect under an incongruent condition, although the priming effect size was reduced. However, the priming effect of the non-athlete group disappeared with incongruent flankers. Event-related potentials revealed that the interaction between subliminal processing and suprathreshold conflict could be displayed in the early stage of perceptual and attention processing (P1 event-related potential component). Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-022-09883-2.

Table tennis players use superior saccadic eye movements to track moving visual targets.

Introduction: Table tennis players perform visually guided visuomotor responses countlessly. The exposure of the visual system to frequent and long-term motion stimulation has been known to improve perceptual motion detection and discrimination abilities as a learning effect specific to that stimulus, so may also improve visuo-oculomotor performance. We hypothesized and verified that table tennis players have good spatial accuracy of saccades to moving targets. Methods: University table tennis players (TT group) and control participants with no striking-sports experience (Control group) wore a virtual reality headset and performed two ball-tracking tasks to track moving and stationary targets in virtual reality. The ball moved from a predetermined position on the opponent's court toward the participant's court. A total of 54 conditions were examined for the moving targets in combinations of three ball trajectories (familiar parabolic, unfamiliar descent, and unfamiliar horizontal), three courses (left, right, and center), and six speeds. Results and discussion: All participants primarily used catch-up saccades to track the moving ball. The TT group had lower mean and inter-trial variability in saccade endpoint error compared to the Control group, showing higher spatial accuracy and precision, respectively. It suggests their improvement of the ability to analyze the direction and speed of the ball's movement and predict its trajectory and future destination. The superiority of the spatial accuracy in the TT group was seen in both the right and the left courses for all trajectories but that of precision was for familiar parabolic only. The trajectory dependence of improved saccade precision in the TT group implies the possibility that the motion vision system is trained by the visual stimuli frequently encountered in table tennis. There was no difference between the two groups in the onset time or spatial accuracy of saccades for stationary targets appearing at various positions on the ping-pong table. Conclusion: Table tennis players can obtain high performance (spatial accuracy and precision) of saccades to track moving targets as a result of motion vision ability improved through a vast amount of visual and visuo-ocular experience in their play.

Inter-arm bone mass and size asymmetries in children tennis players are maturity status specific: a 9-month study on the effects of training time across pubertal change and somatic growth.

PURPOSE: Bone growth with exercise is best assessed by tennis-induced inter-arm asymmetries. Yet, the effects of training and maturation across puberty were unclear. This study explored arm bone growth across 9 months of training in 46 tennis players 7-14 years (25 boys, 21 girls). METHODS: Bone mineral content (BMC) and bone area (BA) were measured from DXA scans. Pubertal status was assessed by Tanner stage (TS) and somatic growth by maturity offset (MO). Children were grouped as pre- (TS I-I), early (TS I-II), and mid/late pubertal (TS II-III). RESULTS: Training time (TT) change in the three groups was 160-170, 190-230, and 200-220 h, respectively. Bone asymmetries were large in all groups (d > 0.8, P < 0.001): 5-18 g (9-21%) and 9-17 g (17-23%) in girls and boys, respectively, for BMC, and 5-15 cm2 (6-13%) and 9-15 cm2 (12-15%) in girls and boys (10-13%), respectively, for BA. BMC and BA change asymmetry peaked at pre-puberty in girls (56%, 46%) and at early puberty in boys (57%, 43%). Asymmetry gains varied with baseline asymmetry (41%) and change in TT (38%) and TS (17%) in BMC, and with baseline asymmetry (58%) and change in MO (17%) and TS (12%) in BA. CONCLUSION: All bone asymmetries were substantial. Tennis-induced bone gains were higher at pre- to early puberty in girls and at early to mid/late puberty in boys. Training enhanced mostly bone mass and maturity status enhanced mostly bone size; sex was not bone-change modeling impactful. Implications are discussed considering certain limitations.

Effects of Proprioceptive Insoles and Specific Core Training on Postural Stability for Preventing Injuries in Tennis.

Tennis is a complex sport based on unpredictability that requires adequate physical and psychological preparation to prevent injuries. The aim of this study was to investigate the effects of 8-week specific core stability training on postural stability in competitive adolescent tennis players, aged between 14 and 19 years old. Sixty-one participants were randomly allocated into two groups: experimental (n = 32) and control (n = 29) groups. The first group wore proprioceptive insoles 8 h a day and performed a detailed training 3 times a week for 8 weeks; the second group only received proprioceptive insoles to wear 8 h a day for 8 weeks. The postural stability parameters (center-of-pressure length, center-of-pressure velocity, and 95% confidence ellipse sway area) included three assessment times: baseline (T0), intermediate test (T1), post-test (T2), and retention test (T3). Data analysis showed a significant improvement in the experimental group compared with the control group, indicating a large effect size in center-of-pressure length, ellipse sway area, and center-of-pressure velocity at T2 and T3 (p < 0.05). In conclusion, our results suggest that a specific and detailed core stability training plays a significant role in improving balance and postural stability in young tennis players, especially in terms of preventing the risk of injury.