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1.
运用文献资料法、专家访谈法、录像观察统计法和乒乓球技战术三段分析等方法,对世界优秀乒乓球运动员波尔处理关键球技术使用习惯和战术运用模式、效果进行了分析和研究。结果表明:波尔关键球发抢段主要是以发中路偏反手逆旋转侧下旋短球为主,结合发强烈逆侧下长球至两角后抢冲或抢拉;接抢段则以正手摆近网短球为主,结合搓两角长球,第4板抢拉或抢冲至对方正、反手大角;相持段主要依赖于正手相持和反手相持得分,与常规球比较看,到了关键球波尔主动侧身相持得分能力明显下降,而反手被动相持得分能力则有显著提高。  相似文献   

2.
Abstract

The main aim of this study was to identify and compare ball speed and hitting accuracy of forehand and backhand groundstrokes between ATP professionals (elite) and high-performance youth players when shots were played cross-court and down the line to a target square. Six elite and seven high-performance tennis players volunteered to participate in the study. A Doppler-radar device and a digital video camera, operating at 120 frames per second, were used to measure ball speed and accuracy of forehand and backhand groundstrokes in the respective situation (cross-court and down the line). The results of 1040 measured groundstrokes indicate that the ball speed of the forehand and the backhand ground stroke was higher in the elite group when analysing (1) all valid shots, (2) the six fastest shots, and (3) the six most accurate shots (all P < 0.05). In addition, all players achieved a higher forehand speed compared with their backhand when balls were directed cross-court (P < 0.01). The participants demonstrated similar ability when considering accuracy of their groundstrokes (P > 0.05). However, a group difference for accuracy was identified when considering the six fastest forehand shots (P<0.05), and the forehand cross-court stroke was played more accurately than the backhand cross-court stroke by both groups (valid shots and six most accurate shots, P<0.05). Moreover, there was no evidence that players who impacted the ball faster were any less accurate than those who impacted the ball more slowly. Analyses for participants actually revealed a negative correlation between ball speed and mean radial error (accuracy) for the backhand down the line (r= ? 0.77, P<0.01). According to the results of this study, ball speed seems to be the determining factor that separates elite from sub-elite tennis players.  相似文献   

3.
Abstract

Variable practice has been shown to be an effective strategy to improve open motor skills. However, the usefulness of this procedure in closed motor skills remains controversial. The following study has the objective of analysing the effects of variability practice in the improvement of a closed skill. The skill studied has been the tennis serve. Thirty young tennis players (13 ± 1.52 years), divided in two groups, took part in this study. One group practiced in variable conditions and the other group in consistency conditions. Both groups performed 12 training sessions (60 serves/session). The variable practice group improved their accuracy significantly compared with the consistency group (F3.25 = 3.078; P = 0.035). The velocity of serve increased after training in both groups (F3.25 = 15.890; P = 0.001). The practice in variable conditions seems to be effective in improving the performance of the tennis serve.  相似文献   

4.
Shots are an essential part of the language of tennis yet little is known about the distinct types of shots in the professional game. In this study, we build a taxonomy of shots for elite tennis players using tracking data from multiple years of men’s and women’s matches at the Australian Open. Our taxonomy is constructed using model-based multi-stage functional data clustering, an unsupervised machine learning approach. Among 270,023 men’s and 178,136 women’s shots, we found 13 distinct types of serves to both the Ad and Deuce court for male players and 17 and 15 types to the Ad and Deuce for female players. More variety was found among serve returns and rally shots compared to the serve; with less variety on the backhand than forehand. There was also more overlap in the physical characteristics of groundstroke shots between male and female players than on serve. Shot type was strongly associated with winning points and shots in the highest speed and lowest net clearance categories tended to be the most effective. This data-driven dictionary of shots provides a framework for analysis of elite player performance, characterizing playing style, and designing more representative practice.  相似文献   

5.
目前,普通高校大学生的网球教学效果不尽人意,尤其是网球的正反手技术的掌握和运用极其不平衡,这直接影响了学生网球技术水平的提高和发展.针对这一现象,打破传统的网球正反手教学顺序(先学习正手抽球技术后学习双手反手抽球技术),提出"先学习双手反手抽球技术后学习正手抽球技术"的教学方法,意欲通过改变网球正反手的教学顺序达到提高...  相似文献   

6.
直拍横打主要解决直拍打法反手位相持能力弱,反手进攻能力差的缺点。王皓是直拍横打的代表人物,在第28届和29届奥运会乒乓球男单决赛中,王皓分别输给了同为直拍单面攻代表人物柳承敏、马琳。对这两场比赛的技战术特点进行了系统分析与研究,探索直拍横打在比赛中的合理运用,对直拍横打的技战术特点进行了探讨,为进一步提高我国直拍横打的技战术水平提供参考。  相似文献   

7.
Elite tennis is characterised by repeated bouts of up to 5-set match play, yet little is known about the technical requirements of shots played. This study therefore investigated technical performance changes over consecutive days of prolonged, simulated tennis match play. A total of 7 well-trained men tennis players performed 4 consecutive days of competitive 4-h match play. Matches were notated to determine between-day changes in groundstroke and serve performance, as well as point and match durations. Changes ≥75% likely to exceed the smallest important effect size (0.2) were considered meaningful and represented as effect size ± 90% confidence interval. Effective playing time reduced on days 3 and 4, alongside likely increases in “stretch” groundstrokes over the 4 days (mean effect size ± 90% confidence interval; 0.57 ± 0.38) and “stretch” backhand returns on days 2 and 3 (0.39 ± 0.54 and 0.67 ± 0.55). Relative unforced errors increased on day 4 (vs. day 2; 0.36 ± 0.22) and second-serve winning percentage reduced after day 1 (?0.47 ± 0.50). Further, a likely increase in emotional outbursts characterised day 3 (vs. day 2; 0.73 ± 0.57). Consecutive-day match play impairs hitting accuracy, stroke positioning and emotional responses; an understanding of which prepares players for elite-standard tennis tournament play.  相似文献   

8.
ABSTRACT

Little is known about the optimal frequency to observe a skilled model, yet this is potentially an important learning variable, and thus was examined in the context of self-controlled learning conditions. Participants chose the schedule in which they interspersed both physical and observational trials of a dance skill. The participants’ choice, however, was governed by an imposed observation frequency (OF) of either 25%, 50%, or 75%. Participants were in one of these OF groups, in addition to another group in which no constraint was put on OF. This last group was predicted to choose an OF of 10%, however, it was determined that they chose a 50% schedule. Consequently, a 10% OF group was added to the experimental protocol. All participants completed a pre-test, followed by an acquisition phase, and then a 24-hr post-test. Physical performance (F(1, 55) = 143.77, p< .001) and cognitive representation (F(1, 55) = 77.68, p< .001) scores both revealed a significant main effect of Test; scores at post-test were higher than those at pre-test. Thus, learning was demonstrated for both measures. No main effect of Group emerged. Consequently, OF varying from 10% to 75%, under self-controlled conditions, were equally beneficial for learning the dance skill.  相似文献   

9.
The Lawn Tennis Association’s mini tennis (MT) is a modified version of tennis consisting of progressive stages; however, there have been few attempts to evaluate how MT might shape performance behaviours. Here, we examine effects of playing MT on the emergence of children’s match-play behaviours in 48 junior tennis players. Performance in 1010 match-play points were filmed and coded across 4 tennis stages (MT Red, MT Orange, MT Green and Full Ball), using a notational analysis system. Recorded performance variables included rally length, first serve percentage and shot type, for the purpose of analysing inter-stage comparisons. Results showed a series of specific adaptations to playing characteristics across the stages, including rally length, shot variety and serve success. MT Red rallies (7.36 ± 6.06) were longer than Full Ball rallies (3.83 ± 2.40), and a higher percentage of forehands were played at MT Red (66.40 ± 8.49%) than at Full Ball stage (45.96 ± 6.47%). Findings suggested that MT stages can afford children more opportunities to develop their skills and elicit different match-play characteristics than Full Ball task constraints. Coaches, therefore, should consider the nature of emergent adaptations when designing practice environments to facilitate learning in young tennis players.  相似文献   

10.
The purpose of this study was to investigate the temporal phases of the archery shot cycle that distinguish the arrows distance from centre, in an attempt to understand critical factors that affect performance. Fifteen archers of varying ability each performed 30 shots at 18 m. Fourteen potential predictor variables were measured for statistical modelling by stepwise multiple linear regression. The results show that pre-shot time (pre-performance routine), follow-through time (post-performance routine), aiming time, speed of the arrow and the %variation in clicker-release time, account for 7.7% of the variation in predicting shot performance. The results have implications for practice demonstrating factors that coaches should focus on to develop their athletes. Further work on pre-, but more importantly, post-performance routines are needed generally within sport research as they are lacking and have been shown to be important contributing factors in a number of sports.  相似文献   

11.
Shooting in biathlon competitions substantially influences final rankings, but the predictability of hits and misses is unknown. The aims of the current study were A) to explore factors influencing biathlon shooting performance and B) to predict future hits and misses. We explored data from 118,300 shots from 4 seasons and trained various machine learning models before predicting 34,340 future shots (in the subsequent season). A) Lower hit rates were discovered in the sprint and pursuit disciplines compared to individual and mass start (P < 0.01, h = 0.14), in standing compared to prone shooting (P < 0.01, h = 0.15) and in the 1st prone and 5th standing shot (P < 0.01, h = 0.08 and P < 0.05, h = 0.05). B) A tree-based boosting model predicted future shots with an area under the ROC curve of 0.62, 95% CI [0.60, 0.63], slightly outperforming a simple logistic regression model and an artificial neural network (P < 0.01). The dominant predictor was an athlete’s preceding mode-specific hit rate, but a high degree of randomness persisted, which complex models could not substantially reduce. Athletes should focus on overall mode-specific hit rates which epitomise shooting skill, while other influences seem minor.  相似文献   

12.
ABSTRACT

Table tennis requires rapid and extreme movements that may result in shoulder adaptations, such as glenohumeral internal rotation deficit, which is a risk factor for several injuries. This study compared range of motion of internal and external rotation and total rotation motion of glenohumeral joint between dominant and non-dominant shoulders of table tennis players. This is a cross-sectional observational study. Twenty healthy male table tennis players that were enrolled in an official table tennis league took part in this study (mean age: 22.9 ± 12.9 years, time of sports practice: 6.2 ± 7.12 years). Measurements of passive glenohumeral external rotation and internal rotation were taken with the individuals in the supine and sidelying positions. Total rotation motion was calculated by summing external and internal rotations. The dominant side showed decreased internal rotation when compared to non-dominant side in both supine (mean difference: 14.9°, p = 0.02) and sidelying positions (mean difference: 16.3°, p = 0.01). No significant difference (p > 0.05) was found for external rotation and total rotation motion between dominant and non-dominant shoulders. The findings indicate that table tennis players exhibit glenohumeral internal rotation deficit of dominant shoulder.  相似文献   

13.
Abstract

A tennis skill test for use in quantifying achievement in the forehand and backhand drive strokes was developed and then validated using 76 college women enrolled in beginning tennis classes. The test consisted of returning balls pitched by a pneumatic ball machine into target areas drawn in chalk on a regulation tennis court. Speed of the subjects' shots was assessed by measuring accumulated time in flight for rounds of 10 trials using a stopwatch. A time factor was then employed to correct the target value total for the trials to adjust for ball speed, thus rewarding the more skilled player who could stroke the ball more firmly while still retaining control. The test-retest reliability of the test was found to be .84, while the validity of the test, using judges' ratings as a criterion, was .83. It was concluded that the test was a valid and reliable test of skill which was closely related to the actual game situation. Percentile norms were developed on a limited number of subjects.  相似文献   

14.
Abstract

Previous research on laterality in sport suggests an over-representation of left-handers in interactive sports such as tennis and cricket. These findings potentially reflect left-handers' advantage over their right-handed competitors in those sports. Although considered crucial for successful performance, the tactical component of their superiority has yet to be analysed. Two studies were conducted to test for a side bias in tennis players' tactical preferences. In the first study, 108 right- and left-handed players of varying skill watched rallies on a computer screen and had to indicate where they would place the ball in the opposing half. The results showed the tactical preference of players to place more balls on a left-handed opponent's mostly stronger forehand side compared with when faced with a right-hander. In the second study, 54 professional tennis matches involving right- and left-handers were analysed with respect to ball placement frequencies on the opponent's backhand side. Significantly fewer balls were hit to the backhand side of a left-handed opponent, thus replicating the findings of Study 1 in on-court situations. Both studies indicate players' preference to place shots to their right irrespective of their opponent's handedness. Findings support the assumption that left-handers might enjoy a strategic advantage in tennis.  相似文献   

15.
Research has revealed that individual soccer goalkeepers respond differently to penalty shots, depending on their specific perceptual and motor capabilities. However, it remains unclear whether analogous differences exist between individual penalty takers, and if specialising in penalty taking affects the occurrence of differences between individuals. The present study examined individual differences in penalty shot speed and accuracy for specialists in penalty taking versus non-specialists. Expert specialist field hockey drag flickers and equivalently skilled non-specialists performed drag flicks towards predetermined targets placed in the face of a standard field hockey goal. Comparisons in shot speed and accuracy were made at a group level (specialists vs. non-specialists) as well as between individuals. Results revealed differences in both speed and accuracy between specialists, but only differences in speed between non-specialists. Specialists generated significantly greater shot speed than non-specialists (P < .001) and were more accurate to some, but not all, targets (top left, P < .006, bottom left P < .001). In addition, it was found that in specialists increasing practice correlated with decreasing accuracy. This may indicate that excessive practice could potentially reduce a specialist’s accuracy in shooting towards specific targets.  相似文献   

16.
部分优秀网球运动员反手切削球技战术研究   总被引：1，自引：0，他引：1  
梁丹  乐仁油 《体育科技》2007,28(4):36-40
采用文献法、观察与分析法、访谈法等多种研究方法,对网球反手切削球技术、战术进行比较全面系统的探讨,总结分析国内、外优秀网球运动员运用反手切削技术、战术的特点及规律,为进一步提高我国网球运动水平提供参考依据。  相似文献   

17.
In golf, unlike most other sports, individual performance is not the result of direct interactions between players. Instead decision-making and performance is influenced by numerous constraining factors affecting each shot. This study looked at the performance of PGA TOUR golfers in 2011 in terms of stability and variability on a shot-by-shot basis. Stability and variability were assessed using Recurrence Quantification Analysis (RQA) and standard deviation, respectively. About 10% of all shots comprised short stable phases of performance (3.7 ± 1.1 shots per stable phase). Stable phases tended to consist of shots of typical performance, rather than poor or exceptional shots; this finding was consistent for all shot categories. Overall, stability measures were not correlated with tournament performance. Variability across all shots was not related to tournament performance; however, variability in tee shots and short approach shots was higher than for other shot categories. Furthermore, tee shot variability was related to tournament standing: decreased variability was associated with better tournament ranking. The findings in this study showed that PGA TOUR golf performance is chaotic. Further research on amateur golf performance is required to determine whether the structure of amateur golf performance is universal.  相似文献   

18.
Abstract

The effectiveness of pre-performance routines on skilled performance in a self-paced skill has yet to be verified. In this study, we examine the importance of temporal and behavioural consistency in these routines. The duration and specific pattern of behaviours exhibited before each free throw (n = 284) were observed during 14 National Basketball Association play-off games. An intra-individual standardized score was calculated for each shot's duration. Each player's dominant behavioural routine was identified and each shot was classified as “sequence followed” or “sequence not followed”. No difference was observed in the success rates of shots associated with brief, long, and regular duration routines (P > 0.05). However, players were more successful when they followed their dominant behavioural sequence (83.77% success) than when they deviated from their specific behavioural pattern (71.43% success) (P < 0.05). The findings are interpreted in light of relevant theory and implications for practice are discussed.  相似文献   

19.
The purpose of this study was to investigate the effect of the racket mass and the rate of strokes on the kinematics and kinetics of the trunk and the racket arm in the table tennis topspin backhand. Eight male Division I collegiate table tennis players hit topspin backhands against topspin balls projected at 75 balls · min?1 and 35 balls · min?1 using three rackets varying in mass of 153.5, 176 and 201.5 g. A motion capture system was used to obtain trunk and racket arm motion data. The joint torques of the racket arm were determined using inverse dynamics. The racket mass did not significantly affect all the trunk and racket arm kinematics and kinetics examined except for the wrist dorsiflexion torque, which was significantly larger for the large mass racket than for the small mass racket. The racket speed at impact was significantly lower for the high ball frequency than for the low ball frequency. This was probably because pelvis and upper trunk axial rotations tended to be more restricted for the high ball frequency. The result highlights one of the advantages of playing close to the table and making the rally speed fast.  相似文献   

20.
The purpose of this study was to create a valid and reliable assessment scale for the evaluation of three basic tennis strokes (forehand, backhand, serve) for 6–12-year-old tennis players, named the Tennis Rating Score for Children (TRSC). Altogether 60 players (21: forehand, 22: backhand, 17: serve) were video recorded (30 frames per second) while performing three main tennis strokes and later evaluated using the TRSC by five tennis trainers at Day 1 and Day 7. Agreement between days and raters was examined using the intraclass correlation coefficients (ICC). A Pearson’s correlation was calculated to determine convergent validity (score related to participant’s level of experience). The reliability between raters was very high for all three main strokes (ICCFOREHAND = 0.874; ICCBACKHAND = 0.877; ICCSERVE = 0.877). The intra-rater test-retests ICCs were also very high (ICCFOREHAND = 0.885; ICCBACKHAND = 0.891; ICCSERVE = 0.887). A large (rFOREHAND = 0.660) and very large (rBACKHAND = 0.730; rSERVE = 0.772) Pearson’s correlations were found between all the ratings and the level of experience. The TRSC is shown to be highly reliable and valid when assessing technical skills in novice players, when compared to actual assessment from coaching experts; this tool may be helpful for tennis coaches to make a more objective diagnostic of the technical level of young tennis players.  相似文献   

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