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2.
In this study, we evaluated the effect of the use of tennis racket string vibration dampers on racket handle vibrations, and perceptions of hand and arm discomfort experienced by tennis players owing to stationary racket impacts. Twenty tennis players (10 males, 10 females) aged 18-29 years volunteered for the study. Two different racket models were impacted at the geometric centre of the racket face and 100 mm distal to the centre both with and without string vibration dampers in place. The participants could neither see nor hear the impacts, and they indicated their discomfort immediately after each impact using a visual analogue scale. An analysis of variance (2 x 2 x 2 factorial) was performed on the scaled discomfort ratings with the factors damping condition, racket type and impact location. No significant differences in discomfort ratings between damped and undamped impacts or between the two racket types were found. Also, central impacts were found to be more comfortable than impacts 100 mm distal to the centre (P< 0.05). There were no significant interaction effects. Vibration traces from an accelerometer mounted on the racket handle revealed that string vibration dampers quickly absorbed high-frequency string vibration without attenuating the lower-frequency frame vibration. In conclusion, we found no evidence to support the contention that string vibration dampers reduce hand and arm impact discomfort. 相似文献
3.
随机选取武汉体育学院10名网球专项学生实施六项专项身体素质测试与功能性动作测试,利用费尔曼等级相关系数对体育院校学生以上两项测试进行系统分析,以此降低网球专项学生因不适宜的日常训练所造成的损伤概率,为我国大众网球的开展储备优秀的师资力量。结果表明,在测试过程中很明显可以观测到运动员肩部和核心区肌群完成功能性动作质量不高;根据斯皮尔曼等级相关分析可以得知,专业体育院校男子网球运动员FMS测试与专项身体素质之间有部分显著性相关,而专业体育院校男子网球运动员FMS测试总分与专项身体素质之间无显著性相关。因此,功能性动作筛查测试只能简易的识别个体的功能限制和不对称发展,而对于预测运动员现有的竞技水平和运动员潜在的竞技能力缺乏一定的效度和准确度。 相似文献
4.
运用文献资料法、数理统计法和比较法,对我国网球女单选手在2006年澳网女单比赛中的技战术指标进行统计分析。结果表明:我国网球女单选手与世界高水平网球女单选手在一发得分率、二发得分率、接发球得分率、破发成功率和非受破坏性失误等技、战术指标上存在明显的差距。 相似文献
5.
The relationship between domestic professional tournament structure in women's tennis and the subsequent professional ranking success of a nation's female players is examined. The 2003 women's professional tennis tournament calendar provided the distribution of events in 33 countries. Criteria used to classify nations' success in women's professional tennis were as follows: number of players with Women's Tennis Association (WTA) points, number of players with Top 200 rankings, and the combined WTA ranking of a nation's Top 5 female players. Pearson product - moment correlations were performed between the number of tournaments and the three criteria. Considerable variation was observed in the number of events organized between nations (USA, n = 56; Thailand, n = 3). All countries had internationally ranked female players, and 24 nations had players ranked in the Top 200. Results revealed relationships between a nation's number of women's professional events and both that nation's number of professionally ranked players (r = 0.60; P < 0.01) and Top 200 players (r = 0.60; P < 0.01), as well as the combined ranking of their Top 5 players (r = -0.52; P < 0.01). While a similar association was found between the number of professional events and players ranked in the men's game, there was no significant correlation between events held and the combined standing of nations' best five ranked players. Governing bodies and national associations in tennis should consider the provision of professional, domestic competition as key to the development of female tennis players. 相似文献
6.
AbstractSuccess in professional tennis is measured, at least in part, by rankings. However, there is little quantitative evidence to inform stakeholders regarding what represents the typical ranking progress of top-ranked players. The objective of this study was therefore to compare the ranking trajectories of male players whom achieved peak professional rankings in the Top 250, 175, 100, 50, 20 and 10. The 11,396 birthdates and weekly professional rankings of all players between 27 August 1973 and 31 October 2011 were collated. The peak ranks for each athlete according to their both chronological age and number of years on tour were identified and athletes were categorised into one of six career–peak ranking bands. One-way analysis of variance tests confirmed distinctive ranking trajectories, which were most pronounced among Top 10 players. The rankings of these players were statistically distinguishable following players’ second year on tour or by 17 years of age. The ranking signature of all Top 100 players emerged as significantly different to players that failed to enter the Top 100 by their fourth year on the tour. Indeed, the representation of ranking as a function of years on tour should be considered for use by tennis policy-makers in the future. 相似文献
7.
运用录像观察、数理统计等方法,对中国女网在2008年澳网单打比赛中的技、战术指标进行统计与分析。结果表明:与国外选手相比,中国女网选手在身体形态、发球速度、一发得分率等方面存在明显差距;中国选手比赛的攻击性与技术稳定性尚待进一步提高。比赛名次与技术指标的相关分析表明:二发平均速度、二发得分率等指标对比赛名次的影响程度较大。 相似文献
8.
Comfort has been shown to be the most desired football boot feature by players. Previous studies have shown discomfort to be related to increased plantar pressures for running shoes which, in some foot regions, has been suggested to be a causative factor in overuse injuries. This study examined the correlation between subjective comfort data and objective plantar pressure for football boots during football-specific drills. Eight male university football players were tested. Plantar pressure data were collected during four football-specific movements for each of three different football boots. The global and local peak pressures based on a nine-sectioned foot map were compared to subjective comfort measures recorded using a visual analogue scale for global discomfort and a discomfort foot map for local discomfort. A weak ( rs = ?0.126) yet significant ( P < 0.05) correlation was shown between the peak plantar pressure experienced and the visual analogue scale rated comfort. The model only significantly predicted ( P > 0.001) the outcome for two (medial and lateral forefoot) of the nine foot regions. Subjective comfort data is therefore not a reliable measure of increased plantar pressures for any foot region. The use of plantar pressure measures is therefore needed to optimise injury prevention when designing studded footwear. 相似文献
9.
文章通过对我国优秀女子网球单打选手与世界优秀女子网球单打选手的比赛录像分析,进一步诊断与评价我国优秀女子网球单打选手的技战术运用特征。结果表明,我国优秀女子网球单打选手的一发成功率较高,得分率较差,发球的攻击性不足;非受迫性失误较高,接发球得分率和破发点较差。发球抢攻技术、接发球抢攻技术以及上网技术的使用率比较低。得分方式有17.8%是靠主动得分,45.3%是靠对手的非受迫性失误得分,36.9%是靠对手的受迫性失误得分;失分的主要方式为非受迫性失误。 相似文献
10.
This research reported here draws on self-organization theories and dynamical system models to investigate the collective behaviour of tennis players. In tennis, the unceasing to-and-fro displacements of a player about a "home" reference position, located in the middle of the baseline, are akin to those of an oscillator, and the reciprocal attending of both players establishes an informational linkage. Thus, theoretically, the displacement of the two players can be analysed as a system formed by two coupled non-linear oscillators. In such a system, relative phase has been shown to be an adept measure of the temporal synchronization between the oscillators. We hypothesized that relative phase is a relevant collective variable to characterize the relative motion of tennis players. Four players were videotaped and their displacements analysed. The results revealed just two stable patterns of synchronization, in-phase and anti-phase, as the players moved in the same or opposite directions, respectively. Moreover, relative phase showed two types of evolution within trials: either it remained stable at in-phase or anti-phase, or it exhibited transitions between these two modes. In accordance with our hypothesis, the results identified relative phase as a pertinent collective variable to represent both invariance and change in the relative displacements of tennis players. Such a finding opens new avenues for investigating dual sports. 相似文献
11.
This research reported here draws on self-organization theories and dynamical system models to investigate the collective behaviour of tennis players. In tennis, the unceasing to-and-fro displacements of a player about a “home” reference position, located in the middle of the baseline, are akin to those of an oscillator, and the reciprocal attending of both players establishes an informational linkage. Thus, theoretically, the displacement of the two players can be analysed as a system formed by two coupled non-linear oscillators. In such a system, relative phase has been shown to be an adept measure of the temporal synchronization between the oscillators. We hypothesized that relative phase is a relevant collective variable to characterize the relative motion of tennis players. Four players were videotaped and their displacements analysed. The results revealed just two stable patterns of synchronization, in-phase and anti-phase, as the players moved in the same or opposite directions, respectively. Moreover, relative phase showed two types of evolution within trials: either it remained stable at in-phase or anti-phase, or it exhibited transitions between these two modes. In accordance with our hypothesis, the results identified relative phase as a pertinent collective variable to represent both invariance and change in the relative displacements of tennis players. Such a finding opens new avenues for investigating dual sports. 相似文献
12.
Purpose: The net height in tennis (0.91 m) is approximately 50% of a professional tennis player’s height. Children are also expected to play with this net height, even though it is approximately 70% of the average 10-year-old’s height. This study examined the immediate effect of lowering net height on the performance characteristics of skilled junior tennis players aged 10 years and younger. Method: Sixteen players were matched in 8 pairs of even tennis ability and same sex. Each pair played 25-min singles matches in 4 conditions that varied in net height (0.91 m, 0.78 m, 0.65 m, and 0.52 m). Match-play characteristics were analyzed via video replay. Results: Results showed that lowering the net height to 0.65 m and 0.52 m led to players adopting a more attacking style of play, as evidenced by a significant increase in the number of winners without a commensurate increase in errors and more shots struck inside the baseline. Lower nets also led to a greater percentage of successful first serves. The lowest net (0.52 m), however, reduced rally length significantly and therefore decreased hitting opportunities. Conclusion: These results offer support for equipment scaling to enhance match-play performance for skilled junior tennis players. We propose that current net height recommendations for junior tennis should be revised. 相似文献
13.
Eighteen elite male tennis players were tested to determine their ability to identify string tension differences between rackets
strung from 210 N (47 lb) to 285 N (64 lb). Each player impacted four tennis balls projected from a ball machine before changing
rackets and repeating the test. Eleven participants (61%) could not correctly detect a 75 N (17 lb) difference between rackets.
Only two participants (11%) could correctly detect a 25 N (6 lb) difference. To establish whether varying string tensions
affected ball rebound dynamics, the ball’s rebound speed and landing position were analysed. The mean rebound ball speed was
117 km h −1, with only the trials from the 210 N racket producing significantly lower ( P < 0.05) rebound speeds than the 235 N and 260 N rackets. This is contrary to previous laboratory-based tests where higher
rebound speeds are typically associated with low-string tensions. The anomaly may be attributable to lower swing speeds from
participants as they were not familiar with such a low string tension. Ball placement did not appear related to string tension,
with the exception of more long errors for the 235 N racket and fewer long errors for the 285 N racket. It was concluded that
elite male tennis players display limited ability to detect changes in string tension, impact the ball approximately 6% faster
than advanced recreational tennis players during a typical rallying stroke, and that ball placement is predominantly unrelated
to string tension for elite performers. 相似文献
14.
Abstract The purpose of this study was to investigate differences between the oversized racquet and the standard-sized racquet in (1) a tennis shot accuracy test on four basic strokes (ground strokes, volley, return of serve, and serve), and (2) a measure of players' subjective evaluation of playability (control, accuracy, power, and feel). Research participants (n = 57) were undergraduate students separated into two skill levels, intermediate (n = 29) and beginners (n = 28). Data were analyzed using a two-factor ANOVA with repeated measures on one factor. Result from the skills tests indicated that both beginning and intermediate groups scores significantly higher when using the oversized racquet. The scores received when using the oversized racquet tended to reflect a general increase in all four components of the skill test, particularly the return of serve. Data indicated that the subjective evaluation of the playing characteristic of each racquet was influenced by the player's skill level. Beginning players favored the oversized racquet, yet intermediate players rated the two racquet types about equal. The investigation suggests that beginning and intermediate tennis players, educators, and tennis teaching professionals should consider using and encouraging the use of oversized racquets. 相似文献
15.
The aim of this study was to determine the match activity and physiological demands of women's tennis during a 3-day clay-court tennis tournament. The activity profile of eight players was determined by filming each competitive match with video cameras. Metabolic-perceptual measurements--blood samples and individual ratings of perceived exertion (RPE)--were taken while the players were sitting during permitted changeover breaks in play. The activity profile of the players was as follows: strokes per rally, 2.5 +/- 1.6; rally duration, 7.2 +/- 5.2 s; rest time between rallies, 15.5 +/- 7.3 s; effective playing time, 21.6 +/- 6.1%; work-to-rest ratio, 1:2.1. Blood lactate concentration [2.2 +/- 0.9 mmol x l(-1) (n = 50) vs. 2.2 +/- 0.7 mmol x l(-1) (n = 48)] and RPE values [12.2 +/- 2.4 (n = 57) vs. 12 +/- 2.3 (n = 57)] were not significantly different (P = 0.65-0.78) between service and return games. The results highlight the importance of taking these factors (i.e. activity patterns and physiological profile) into account when planning training strategies for competitive females players. As such, tennis training regimes should be adapted to the specific demands imposed by match-play in female players on a clay-court surface. 相似文献
16.
运用文献资料、录像观察、数理统计等研究方法对场地类型与网球运动员竞技能力发展的关系进行探讨。由于研究对象中以草地球场为主导训练环境的球员样本极少,本研究主要考察以硬地、红土场以及硬地和红土结合三种球场类型为主导训练场地类型的职业网球运动员在排名上是否存在差异。以1997—2005年ITF(国际网联)青年赛年度前10名运动员共87名男子职业球员的ATP排名进行方差分析。预分析发现,职业网球运动员获取最高职业排名的平均年限为5.8年,因此对本文研究对象ATP排名的数据获取底线为2009年。结果表明:红土场地训练环境成长的球员排名与另外两种场地环境下成才的球员最高职业排名具有显著性差异(P〈0.05,红土场球员排名平均数为121,标准差为131)。查阅国内外文献资料,从逻辑上分析了多年红土训练可能存在的额外训练效应,并提示场地因素可能成为预测职业网球运动员最高排名的指标之一。 相似文献
17.
This study was conducted to validate and evaluate the "Hit & Turn Tennis Test", an acoustically progressive on-court endurance test for tennis players. Ninety-eight competitive tennis players (53 males, 45 females) of different age groups participated in the study. For validation, the adult male players completed three Hit & Turn tests, one on a clay court and two on a carpet surface, a tennis-specific ball machine test and an incremental treadmill run in a randomized order. A stronger correlation between maximal performance (r = 0.81, P < 0.01) and maximal oxygen uptake (r = 0.96, P < 0.01) was observed between the Hit & Turn test and the ball machine test, than between the Hit & Turn test and the treadmill test. For test-retest, we found a significant correlation between maximal performance on the same (r = 0.83, P < 0.01) and on different surfaces (r = 0.74, P < 0.01). During test evaluation, maximal performance was higher in males than in females (P < 0.01) and increased by consecutive age group in boys (P < 0.01) but not in girls (P = 0.97). In conclusion, Hit & Turn maximum test performance can be recommended as a valid and reliable indicator for tennis-specific endurance. 相似文献
18.
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 (ICC FOREHAND = 0.874; ICC BACKHAND = 0.877; ICC SERVE = 0.877). The intra-rater test-retests ICCs were also very high (ICC FOREHAND = 0.885; ICC BACKHAND = 0.891; ICC SERVE = 0.887). A large (r FOREHAND = 0.660) and very large (r BACKHAND = 0.730; r SERVE = 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
19.
The objective was to systematically review the literature on risk factors and prevention programs for musculoskeletal injuries among tennis players. PubmedMedline, Embase, CINAHL, Cochrane, SportDiscus were searched up to February 2017. Experts in clinical and epidemiological medicine were contacted to obtain additional studies. For risk factors, prospective cohort studies (n > 20) with a statistical analysis for injured and non-injured players were included and studies with a RCT design for prevention programs. Downs&Black checklist was assessed for risk of bias for risk factors. From a total of 4067 articles, five articles met our inclusion criteria for risk factors. No studies on effectiveness of prevention programs were identified. Quality of studies included varied from fair to excellent. Best evidence synthesis revealed moderate evidence for previous injury regardless of body location in general and fewer years of tennis experience for the occurrence of upper extremity injuries. Moderate evidence was found for lower back injuries, a previous back injury, playing >6hours/week and low lateral flexion of the neck for risk factors. Limited evidence was found for male gender as a risk factor. The risk factors identified can assist clinicians in developing prevention-strategies. Further studies should focus on risk factor evaluation in recreational adult tennis players. 相似文献
20.
In this study, we examined the relationship between upper limb joint movements and horizontal racket head velocity to clarify joint movements for developing racket head speed during tennis serving. Sixty-six male tennis players were videotaped at 200 Hz using two high-speed video cameras while hitting high-speed serves. The contributions of each joint rotation to horizontal racket velocity were calculated using vector cross-products between the angular velocity vectors of each joint movement and relative position vectors from each joint to the racket head. Major contributors to horizontal racket head velocity at ball impact were shoulder internal rotation (41.1%) and wrist palmar flexion (31.7%). The contribution of internal rotation showed a significant positive correlation with horizontal racket head velocity at impact (r = 0.490, P < 0.001), while the contribution of palmar flexion showed a significant negative correlation (r = - 0.431, P < 0.001). The joint movement producing the difference in horizontal racket head velocity between fast and slow servers was shoulder internal rotation, and angular velocity of shoulder internal rotation must be developed to produce a high racket speed. 相似文献
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