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1.
The purpose of this study was to determine the nature and effect of certain highly patterned behaviours utilized prior to free-throw shooting in basketball. Ten female basketball players comprising the varsity squad of Texas Christian University, Fort Worth, Texas, USA served as subjects for this study. Subjects were filmed with a high-speed camera and monitored for heart rate during the performance of 10 free throws in each of two conditions: ritual and non-ritual. For the ritual condition, subjects were given unlimited time and freedom of movement prior to each free-throw attempt. For the non-ritual condition, subjects were not restricted by time, but were instructed to shoot the ball without utilizing any movements other than those required to project the ball to the goal. Dependent measures were characteristics of behaviours, physiological changes measured by heart rates, mechanical data (speed, height and angle of release), and number of successful attempts. Condition x trials analyses of variance and low standard deviation concerning characteristics of behaviours indicated that the idiosyncratic behaviours prior to free-throw shooting were rituals of the auto-communicative type. Results indicated no significant difference between conditions for free-throw success. However, partial correlation between dependent measures and successful free-throw attempts indicated that duration of behaviours was most crucial to free-throw shooting success. 相似文献
2.
The purpose of this study was to determine the optimum release conditions for the free throw in men's basketball. The study used hundreds of thousands of three-dimensional simulations of basketball trajectories. Five release variables were studied: release height, release speed, launch angle, side angle, and back spin. The free throw shooter was assumed to shoot at 70% and to release the ball 2.134 m (7 ft) above the ground. We found that the shooter should place up to 3 Hz of back spin on the ball, should aim the ball towards the back of the ring, and should launch the ball at 52 degrees to the horizontal. We also found that it is desirable to release the ball as high above the ground as possible, as long as this does not adversely affect the player's launch consistency. 相似文献
3.
Chau M. Tran 《Journal of sports sciences》2013,31(11):1147-1155
Abstract The purpose of this study was to determine the optimum release conditions for the free throw in men's basketball. The study used hundreds of thousands of three-dimensional simulations of basketball trajectories. Five release variables were studied: release height, release speed, launch angle, side angle, and back spin. The free throw shooter was assumed to shoot at 70% and to release the ball 2.134 m (7 ft) above the ground. We found that the shooter should place up to 3 Hz of back spin on the ball, should aim the ball towards the back of the ring, and should launch the ball at 52° to the horizontal. We also found that it is desirable to release the ball as high above the ground as possible, as long as this does not adversely affect the player's launch consistency. 相似文献
4.
A completely general three-dimensional dynamic model is presented for the motion of basketball shots that may contact the rim, the backboard, the bridge between the rim and board, and possibly the board and the bridge simultaneously. Non-linear ordinary differential equations with six degrees of freedom describe the ball angular velocity and ball centre position. The model includes radial ball compliance and damping and contains five sub-models: purely gravitational flight, and ball-rim, ball-bridge, ball-board, and ball-bridge-board contact. Each contact sub-model has both slipping and non-slipping motions. Switching between the sub-models depends on the reaction force at, and velocity of, the contact point. Although the model can be used to study shots from any point on the court, we here use it to study the sets of free throw release angle, velocity, angular velocity, and lateral deviation angle that result in success (capture), as well as underhand free throws and those using an under-inflated ball. Free throw shots with larger backspin, lower inflation pressures, and underhand release conditions are shown to result in larger capture percentages. 相似文献
5.
Abstract A completely general three-dimensional dynamic model is presented for the motion of basketball shots that may contact the rim, the backboard, the bridge between the rim and board, and possibly the board and the bridge simultaneously. Non-linear ordinary differential equations with six degrees of freedom describe the ball angular velocity and ball centre position. The model includes radial ball compliance and damping and contains five sub-models: purely gravitational flight, and ball – rim, ball – bridge, ball – board, and ball – bridge – board contact. Each contact sub-model has both slipping and non-slipping motions. Switching between the sub-models depends on the reaction force at, and velocity of, the contact point. Although the model can be used to study shots from any point on the court, we here use it to study the sets of free throw release angle, velocity, angular velocity, and lateral deviation angle that result in success (capture), as well as underhand free throws and those using an under-inflated ball. Free throw shots with larger backspin, lower inflation pressures, and underhand release conditions are shown to result in larger capture percentages. 相似文献
6.
Abstract Magnitudes and timings of kinematic variables have often been used to investigate technique. Where large inter-participant differences exist, as in basketball, analysis of intra-participant variability may provide an alternative indicator of good technique. The aim of the present study was to investigate the joint kinematics and coordination-variability between missed and successful (swishes) free throw attempts. Collegiate level basketball players performed 20 free throws, during which ball release parameters and player kinematics were recorded. For each participant, three misses and three swishes were randomly selected and analysed. Margins of error were calculated based on the optimal-minimum-speed principle. Differences in outcome were distinguished by ball release speeds statistically lower than the optimal speed (misses ?0.12 ± 0.10m · s?1; swishes ?0.02 ± 0.07m · s?1; P < 0.05). No differences in wrist linear velocity were detected, but as the elbow influences the wrist through velocity-dependent-torques, elbow–wrist angle–angle coordination-variability was quantified using vector-coding and found to increase in misses during the last 0.016s before ball release (P < 0.05). As the margin of error on release parameters is small, the coordination-variability is small, but the increased coordination-variability just before ball release for misses is proposed to arise from players perceiving the technique to be inappropriate and trying to correct the shot. The synergy or coupling relationship between the elbow and wrist angles to generate the appropriate ball speed is proposed as the mechanism determining success of free-throw shots in experienced players. 相似文献
7.
Button C MacLeod M Sanders R Coleman S 《Research quarterly for exercise and sport》2003,74(3):257-269
The analysis of variability both within and between performers can reveal important information about how athletes satisfy situational constraints. Transitory changes in the basketball free-throw shot were examined across different stages in skill development. Six female basketball players were selected, representing a range of playing expertise (pretest: 0-90% baskets scored). Each participant was video recorded performing 30 shots. Contrary to predictions, there was not a clear pattern of a reduction in trajectory variability with increasing skill level. However, improvements in skill level were associated with an increasing amount of intertrial movement consistency from the elbow and wrist joints. It is suggested that the angular motions of the elbow and wrist joints were compensated for each other toward the end of each throw to adapt to subtle changes in release parameters of the ball. 相似文献
8.
运用数理统计等方法对中国男篮在伦敦奥运会上的攻防技术统计进行统计分析,研究表明:中国男篮身高优于对手,但队员年龄结构不合理,体重和克托莱指数仍处于劣势;在进攻方面,中国男篮存在投篮次数的不足的问题,特别是3分球投篮数与对手差距较大,助攻能力上与对手的差距也较大;在防守方面,中国男篮在盖帽、抢断技术上与对手差距不显著,而篮板球总数上具有显著性差距。并对中国男篮存在的问题提出针对性建议,旨在为中国篮球竞技能力的提高提供参考。 相似文献
9.
中国国家男子篮球队技术指标与比赛成绩的相关分析 总被引：3，自引：0，他引：3
通过文献调研、数理统计等方法计算第15届世界男子篮球锦标赛8强球队比赛名次和各项技术统计的相关系数,各指标对比赛名次影响的重要程度依次是:场均罚球次数、罚球得分、抢断、失误、犯规、2分球命中率、场均得分、3分球命中率、3分得分、2分球投篮次数,2分占总分比例、3分占总分比例;中国队的优势指标:罚球命中率、盖帽、罚球得分、场均得分,但这些指标与比赛名次呈低度相关。中国队的劣势指标:抢断、失误、犯规,这些指标对比赛名次呈高度相关,是制约中国队走向世界强队的关键因素。 相似文献
10.
Raôul R. D. Oudejans Sjoerd Heubers Jean-René J. A. C. Ruitenbeek Thomas W. J. Janssen 《Research quarterly for exercise and sport》2013,84(3):464-469
We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible. Participants drove under a large screen that initially blocked the basket. As soon as they saw the basket they shot. When training with the screen, shooting percentages increased. We conclude that visual control training is an effective method to improve wheelchair basketball shooting. The findings support the idea that perceptualmotor learning can be enhanced by manipulating relevant constraints in the training environment, even for expert athletes. 相似文献
11.
通过对世界首届洲际杯篮球邀请赛的分析和比较,揭示出世界强队在身体和比赛技术统计等方面的一些基本特征和规律。与之相比,中国男篮的身高已经进入了世界先进行列,比赛中也显示出了内线的较强实力以及在防守方面所取得的显著进步。但外围3分球攻击的低效率和篮板球的差距成为中国男篮发展的最大障碍。 相似文献
12.
The precise influence of serve type and serve ball speed on beach volleyball performance is unclear. We examined the relationship between serve type and speed and their effectiveness during the 2008 Men's and Women's Open World Tour Tournament. Three hundred and seventy-eight and 375 serves performed by men and women respectively from the main draw tournament were analysed. Serve speed was recorded using a radar gun. Two expert observers recorded serve speed, serve mode, serve effectiveness and rally outcome. There was no relationship between serve speed and its effectiveness for men (r = -0.047, P > 0.05) and for women (r = -0.048, P > 0.05). However, there was a relationship between serve ball speed and its effectiveness both for men and women, when speed was categorised into three groups. There was a better balance between negative and positive outcomes at medium speeds for men and at low and high speeds for women. There was a relationship between ranking and serve ball speed only for women and between ranking and type of serve for both genders. There was no relationship between rally outcome and serve effectiveness. The combination of high ball speed and jump serve is characteristic of high ranking women but not of men. 相似文献
13.
运用文献资料、录像观察、逻辑分析等方法,对中国男篮在"无姚时代"伦敦奥运会篮球小组赛的防守技术分析研究。研究结果表明:伦敦奥运会上中国男篮的整体防守技术落后其他5支球队。比赛中场均防守篮板球和抢断上与对手有着显著的差距,场均盖帽数在小组赛中处于优势,并且失误与犯规方面也存在着不足。 相似文献
14.
A dynamic model for motion of a basketball on the rim is derived. The model is used to investigate shot success sensitivity
to initial conditions and to search for initial conditions that lead to long rim contact times. Nonlinear ordinary differential
equations describe three components of ball angular velocity and contact point position on the toroidal rim. The model includes
radial ball compliance and dissipation and contains three sub-models describing slipping contact, nonslipping contact and
purely gravitational flight. Switching between the three sub-models depends on contact point velocity and friction forces.
Equivalent radial stiffness and damping constants are estimated using experimental ball force-deflection hysteresis data.
General initial conditions almost always involve slip of the ball on the rim. Bouncing on the rim can also occur. After contact
it is possible for the ball to enter the rim with its centre passing significantly below the rim plane before rising and ultimately
escaping. Exotic quasi-equilibrium periodic circular trajectories exist inside but below the rim plane, relying for their
existence on a combination of centripetal force, friction and gyroscopic precession of radial spin about the contact point.
Trajectories, and consequent ball capture or escape, are extremely sensitive to initial conditions, especially rim contact
position and backspin angular velocity. Backspin aids capture on longrolling trajectories. 相似文献
15.
The main aim of this study was to identify significant relationships between selected anthropometric and kinematic variables and ball release speed. Nine collegiate fast-medium bowlers (mean +/- s: age 21.0 +/- 0.9 years, body mass 77.2 +/- 8.1 kg, height 1.83 +/- 0.1 m) were filmed and reconstructed three-dimensionally. Ball release speeds were measured by a previously validated Speedchek Personal Sports Radar (Tribar Industries, Canada). Relationships between selected anthropometric variables and ball release speed and between kinematic variables and ball release speed were investigated using Pearson's product-moment correlation coefficients (r). A significant relationship was found between the horizontal velocity during the pre-delivery stride (r = 0.728, P < 0.05) and ball release speed (31.5 +/- 1.9 m(-1) s(-1)). We believe that the high correlation was due to the bowlers using techniques that allowed them to contribute more of the horizontal velocity created during the run-up to ball release speed. We also found that the angular velocity (40.6 +/- 3.4 rad x s(-1)) of the right humerus had a low correlation (r = 0.358, P > 0.05) with ball release speed. Although the action of the wrist was not analysed because of an inadequate frame rate, we found high correlations between ball release speed and shoulder-wrist length (661 +/- 31 mm; r = 0.626, P < 0.05) and ball release speed and total arm length (860 +/- 36 mm; r = 0.583, P < 0.05). We conclude that the variance in release speed within this group may be accounted for by the difference in radial length between the axis of rotation at the glenohumeral joint and the release point. 相似文献
16.
对第28届奥运会中国女篮和参赛队中锋的进攻技术能力进行比较研究，结果表明，中国女篮中锋在进攻技术能力上与国外强队之间的差距主要表现在抢位接球能力、个人攻击手段以及近距离个人攻击效果等方面，建议中国女篮应提倡更先进的篮球训练理念，增加更多的国际大赛经验，选拔和培养更优秀的教练员。 相似文献
17.
通过搜集CUBA与NCAA相关的视频、文献,运用调查法、比较法和文献资料法将CUBA与NCAA篮球一级联赛进行对比研究分析,了解我国CUBA篮球水平的现状,深入分析我国篮球运动在人才培养中存在的问题。研究结果表明:由于中美文化存在着差异,中美篮球运动员在身体素质、培育模式上各有不同。因此,CUBA应在借鉴美国NCAA篮球一级联赛成功经验的基础上,加强管理,探索出适合自身发展的培育模式,争取成为我国培育篮球运动后备人才的基地。 相似文献
18.
徐泽 《山东体育学院学报》2008,24(11)
通过文献资料和逻辑分析等方法，从篮球文化构成的三个层面上对NCAA和CUBA进行比较分析，认为现阶段“CUBA成不了中国的NCAA”。CUBA在文化迁移中有自身的局限性：精神文化层面，文化背景的迥异导致对篮球的精神、风格、价值和理念等认识上出现差异；行为制度文化层面，体制的不同造成文化迁移有心无力。随着经济的全球化和中国的发展，NCAA在物质文化层面有更多的东西可以被CUBA移植和借鉴，制约CUBA篮球文化迁移的物质因素逐步消除，篮球运动在中国大学的开展将呈现出前所未有的喜人前景。 相似文献
19.
采用文献资料法对第14届女篮世界锦标赛参赛队伍,特别是中国队的得分情况进行分析.结果显示,世界强队在三分球和罚球命中率上占有绝对优势.用数理统计法对第5届CUBA女篮优秀队伍的得分状况进行分析.结果显示,CUBA女篮优秀队伍在三分球和罚球命中率方面处于相对弱势,就此分析并提出改进对策. 相似文献
20.
Paul S. Glazier Giorgos P. Paradisis Stephen-Mark Cooper 《Journal of sports sciences》2013,31(12):1013-1021
The main aim of this study was to identify significant relationships between selected anthropometric and kinematic variables and ball release speed. Nine collegiate fast-medium bowlers (mean - s : age 21.0 - 0.9 years, body mass 77.2 - 8.1 kg, height 1.83 - 0.1 m) were filmed and reconstructed three-dimensionally. Ball release speeds were measured by a previously validated Speedchek? Personal Sports Radar (Tribar Industries, Canada). Relationships between selected anthropometric variablesand ball release speed and between kinematic variables and ball release speed were investigated using Pearson's product-moment correlation coefficients ( r ). A significant relationship was found between the horizontal velocity during the pre-delivery stride ( r = 0.728, P ? 0.05) and ball release speed (31.5 - 1.9 m·s -1 ). We believe that the high correlation was due to the bowlers using techniques that allowed them to contribute more of the horizontal velocity created during the run-up to ball release speed. We also found that the angular velocity (40.6 - 3.4 rad·s -1 ) of the right humerus had a low correlation ( r = 0.358, P > 0.05) with ball release speed. Although the action of the wrist was not analysed because of an inadequate frame rate, we found high correlations between ball release speed and shoulder-wrist length (661 - 31 mm; r = 0.626, P ? 0.05) and ball release speed and total arm length (860 - 36 mm; r = 0.583, P ? 0.05). We conclude that the variance in release speed within this group may be accounted for by the difference in radial length between the axis of rotation at the glenohumeral joint and the release point. 相似文献