Physical fitness and stroke performance in healthy tennis players with different competition levels: A systematic review and meta-analysis

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.

Analyzing game statistics and career trajectories of female elite junior tennis players: A machine learning approach

Tennis is a popular and complex sport influenced by various factors. Early training increases the risk of career dropout before peak performance. This study analyzed game statistics of World Junior Tennis Final participants (2012-2016), their career paths and it examined how game statistics impact rankings of top 300 female players, aiming to develop an accurate model using percentage-based variables. Descriptive and inferential statistics, including neural networks, were employed. Four machine learning models with categorical predictors and one response were created. Seven models with up to 18 variables and one ordinal (WTA rank) were also developed. Tournament rankings could be predicted using categorical data, but not subsequent professional rankings. Although effects on rankings among top 300 female players were identified, a reliable predictive model using only percentage-based data was not achieved. AI models provided insights into rankings and performance indicators, revealing a lower dropout rate than reported. Participation in elite junior tournaments is crucial for career development and designing training plans in tennis. Further research should explore game statistics, dropout rates, additional variables, and fine-tuning of AI models to improve predictions and understanding of the sport.

Measuring and assessing motor skills of selected Croatian U12, U14 and U16 tennis players

Purpose: The aim of this research is to analyse and to determine the differences between tennis players in younger age categories (U12, U and U16) in certain motor skills. Methods: A total of 60 tennis players ranked in the rankings of the Croatian Tennis Federation were measured by using 10 tests for assessing explosive strength in jump, speed, agility, and trunk strength. The tennis players were divided into three groups of 20 respondents, depending on the age category in which they compete. Statistically significant differences (p < 0.05) between all age categories were found in indicators of frontal and lateral agility, running speed in the 20-m shuttle run test, and explosive strength in jump and repetitive trunk strength. Results: The results of the conducted tests indicate a linear development trend for the mentioned skills in relation with the increase of chronological age of the tennis players. Statistically significantly better results were shown between test subjects under 14 years compared to test subjects under 12 years in tests for the assessment of agility (SST,A9-3-6-3-9), in the 20 m sprint test, in tests of explosive strength of lower extremities (CMJ, CMJmax,SJ) and in the test of repetitive trunk strength (TF). Subjects under 16 years achieved significantly better results compared to subjects under 14 years in tests for assessing agility (SST, A9-3-6-3-9), speed (SRT5m, SRT10m, SRT20m) and explosiveness (CMJ, CMJmax, SJ). Players under 16 years recorded significantly better results in all tests for assessing agility (SST,A9-3-6-3-9), speed (SRT5m, SRT10m, SRT20m), explosiveness of the lower extremities (CMJ, CMJmax, SJ) and in the test for assessing repetitive trunk strength (TF). Statistically significant differences were not detected in tests of running speed in the 5-m and 10-m shuttle run tests among U12 and U14 tennis players, nor between U14 and U16 tennis players in the 60-s trunk flexion test. The highest heterogeneity of results in a single age category was determined in the test for assessing isometric trunk strength, and thus tennis players of different age categories do not differ significantly in this skill. Conclusion: The results of this research point to the development of specific motor skills in accordance with the increase of game demands and chronological age, however, also refer to the problem of muscle imbalance between front and back trunk musculature. Physical conditioning of young tennis players should be multilaterally directed in order to enable injury prevention and adjustment of tennis players to competitive demands.

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.

Effects of plyometric training on technical skill performance among athletes: A systematic review and meta-analysis

BACKGROUND

The literature has proven that plyometric training (PT) improves various physical performance outcomes in sports. Even though PT is one of the most often employed strength training methods, a thorough analysis of PT and how it affects technical skill performance in sports needs to be improved.

METHODS

This study aimed to compile and synthesize the existing studies on the effects of PT on healthy athletes' technical skill performance. A comprehensive search of SCOPUS, PubMed, Web of Science Core Collection, and SPORTDiscus databases was performed on 3rd May 2023. PICOS was employed to establish the inclusion criteria: 1) healthy athletes; 2) a PT program; 3) compared a plyometric intervention to an active control group; 4) tested at least one measure of athletes' technical skill performance; and 5) randomized control designs. The methodological quality of each individual study was evaluated using the PEDro scale. The random-effects model was used to compute the meta-analyses. Subgroup analyses were performed (participant age, gender, PT length, session duration, frequency, and number of sessions). Certainty or confidence in the body of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE).

RESULTS

Thirty-two moderate-high-quality studies involving 1078 athletes aged 10-40 years met the inclusion criteria. The PT intervention lasted for 4 to 16 weeks, with one to three exercise sessions per week. Small-to-moderate effect sizes were found for performance of throwing velocity (i.e., handball, baseball, water polo) (ES = 0.78; p < 0.001), kicking velocity and distance (i.e., soccer) (ES = 0.37-0.44; all p < 0.005), and speed dribbling (i.e., handball, basketball, soccer) (ES = 0.85; p = 0.014), while no significant effects on stride rate (i.e., running) were noted (ES = 0.32; p = 0.137). Sub-analyses of moderator factors included 16 data sets. Only training length significantly modulated PT effects on throwing velocity (> 7 weeks, ES = 1.05; ≤ 7 weeks, ES = 0.29; p = 0.011). The level of certainty of the evidence for the meta-analyzed outcomes ranged from low to moderate.

CONCLUSION

Our findings have shown that PT can be effective in enhancing technical skills measures in youth and adult athletes. Sub-group analyses suggest that PT longer (> 7 weeks) lengths appear to be more effective for improving throwing velocity. However, to fully determine the effectiveness of PT in improving sport-specific technical skill outcomes and ultimately enhancing competition performance, further high-quality research covering a wider range of sports is required.

Plantar pressure is changed to increase post-impact ball speed during longline forehand and backhand groundstroke in elite female tennis players

Introduction

Achieving high ball speed during the execution of groundstrokes represents a performance-relevant factor in tennis. However, it is unclear how plantar pressure data undergo change during the execution of groundstrokes by tennis players to achieve high postimpact ball speed. Thus, the objective of the present study is to determine how tennis players change the plantar pressure in each foot when they execute longline forehand and backhand groundstrokes in order to increase postimpact ball speed.

Methods

Seventeen healthy nationally ranked female tennis players (mean age: 21.7 ± 7.7 years) participated in this study. The players performed longline forehand and backhand groundstrokes (topspin) at four postimpact ball speed levels, i.e., at 80 km/h, 90 km/h, 100 km/h, and v_max. Plantar pressure was measured in each foot [i.e., dominant (equals the stroke arm) and non-dominant] using flexible instrumented insoles.

Results

Irrespective of the stroke technique, the repeated measures ANOVA procedure showed significant ball speed × foot dominance interactions. For the forehand stroke, post hoc analyses revealed significantly increased (dominant foot) and decreased (non-dominant foot) pressure values when the postimpact ball speed increased from 100 km/h to v_max. For the backhand stroke, the post hoc analyses yielded significantly decreased (dominant and non-dominant foot) plantar pressure values when the postimpact ball speed increased from 100 km/h to v_max. There were no further significant differences between the other ball speed levels.

Discussion

The significantly varying plantar pressure changes depending on the stroke technique and foot dominance to increase postimpact ball speed suggest that specific physical exercises related to the foot (dominant vs. non-dominant foot) and groundstroke (forehand vs. backhand) seem to be necessary for plantar pressure optimization.

Effect of stroke direction on plantar pressure in each foot during the forehand and backhand stroke among healthy adult tennis players of different performance levels

BACKGROUND

In tennis, previous studies have shown differences in plantar pressure depending on tennis-specific movements (i.e., baseline play, serve & volley play, change of direction), playing surface (e.g., hard, grass, or clay), and serve type (e.g., slice, topspin or flat). However, the influence of stroke direction on plantar pressure in tennis players with diverging skill level is unknown. Thus, the purpose of this study was to determine the effect of stroke direction on plantar pressure in each foot during the forehand and backhand stroke among players of different performance levels.

METHODS

Thirty-nine female and male healthy adult tennis players (mean ± SD age: 23.5 ± 6.4 years) representing athletes from three performance levels (recreational, intermediate, advanced) participated in this study. The players performed longline/cross forehand and backhand groundstrokes (topspin) on a clay court while plantar pressure distribution was measured in each foot using flexible instrumented insoles.

RESULTS

The three-way ANOVA (performance level × stroke direction × foot dominance) showed (a) no significant differences in plantar pressure data between cross and longline strokes in almost all cases, (b) in part, significantly larger pressure values in advanced compared to intermediate and recreational players, and (c) significantly larger pressure data for the dominant compared to the non-dominant foot in nearly all comparisons.

CONCLUSION

Regarding an appropriate plantar pressure distribution, our results suggest that during training of especially recreational and intermediate players attention should be paid to the feet rather than to stroke direction.

Effects of athletic training on physical fitness and stroke velocity in healthy youth and adult tennis players: A systematic review and meta-analysis

Better physical fitness and stroke velocity in healthy elite compared to sub-elite tennis players have been shown in previous studies. However, evidence-based knowledge regarding the effectiveness of athletic training on physical fitness and stroke velocity is currently lacking. Thus, the objective of this systematic review with meta-analysis was to characterize, aggregate, and quantify athletic training effects on measures of physical fitness and stroke velocity in healthy youth and adult tennis players. A computerized systematic literature search was performed in the databases PubMed, Web of Science, and SportDiscus from their inception date to August 2022. Studies were included, among others, if the intervention period lasted a minimum of four weeks and if at least one parameter of physical fitness (i.e., speed, agility, lower-extremity muscle power, upper-extremity muscle power/strength, endurance, balance, flexibility) or stroke performance (i.e., stroke velocity) was tested. Initially, 11,511 articles were identified, after removing duplicates and assessing abstracts and full texts, 24 articles were used to calculate weighted standardized mean differences (SMD). For measures of physical fitness, athletic training resulted in small (speed: SMD = 0.44), moderate (endurance: SMD = 0.61, upper-extremity muscle power: SMD = 0.72; flexibility: SMD = 0.63), and large (agility: SMD = 0.93, lower-extremity muscle power: SMD = 0.88; upper-extremity muscle strength: SMD = 0.90; balance: SMD = 0.88) effects. Further, a large effect (SMD = 0.90) on stroke velocity was detected. The additionally performed sub-analyses showed differences in the effectiveness of athletic training on variables of physical fitness and stroke speed when considering players' age (i.e., youth players: <18 years; adult players: ≥18 years). Precisely, there was a high potential for training-related adaptations in adult players with respect to lower-extremity muscle power, upper-extremity muscle strength, and stroke velocity and in youth players with respect to endurance. Interventions to promote physical fitness and stroke velocity in healthy tennis players revealed varying levels of effectiveness ranging from small to large and these were additionally affected by players' age. Therefore, future studies should investigate modalities to increase training efficacy in youth and adult tennis players, especially for fitness components that showed small- to moderate-sized changes.

Effects of plyometric training on skill and physical performance in healthy tennis players: A systematic review and meta-analysis

Background: Plyometric training (PT) has been researched extensively in athletic populations. However, the effects of PT on tennis players are less clear. Methods: We aim to consolidate the existing research on the effects of PT on healthy tennis players' skill and physical performance. On 30th May 2022, a comprehensive search of SCOPUS, PubMed, Web of Science, and SPORTDiscus (via EBSCOhost) databases was performed. PICOS was employed to define the inclusion criteria: 1) healthy tennis players; 2) a PT program; 3) compared a plyometric intervention to a control group or another exercise group, and single-group trials; 4) tested at least one measures of tennis skill or physical performance; and 5) non-randomized study trials and randomized control designs. Individual studies' methodological quality was evaluated by using the Cochrane RoB-2 and ROBINS-I instruments. Using Grading of Recommendations Assessment, Development, and Evaluation (GRADE), the certainty of the body of evidence for each outcome was assessed, and Comprehensive Meta-Analysis software was employed for the meta-analysis. Results: Twelve studies comprising 443 tennis players aged 12.5-25 years were eligible for inclusion. The PT lasted from 3 to 9 weeks. Eight studies provided data to allow for the pooling of results in a meta-analysis. A moderate positive effect was detected for PT programs on maximal serve velocity (ES = 0.75; p < 0.0001). In terms of measures of physical performance, small to moderate (ES = 0.43-0.88; p = 0.046 to < 0.001) effects were noted for sprint speed, lower extremity muscle power, and agility. While no significant and small effect was noted for lower extremity muscle strength (ES = 0.30; p = 0.115). We found no definitive evidence that PT changed other parameters (i.e., serve accuracy, upper extremity power and strength, reaction time, and aerobic endurance). Based on GRADE, the certainty of evidence across the included studies varied from very low to moderate. Conclusion: PT may improve maximal serve velocity and physical performance components (sprint speed, lower extremity muscular power, and agility) for healthy tennis players; however, more high-quality evidence about the effects of PT on the skill and physical performance of tennis players merits further investigation. Systematic Review Registration: [https://inplasy.com/], identifier [INPLASY202250146].