共查询到20条相似文献，搜索用时 31 毫秒
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.
This paper compares the free-throw performance of men and women in the National Collegiate Athletic Association (NCAA), taking into account differences in ball size, ball stiffness, and release height. Although some claim that men are more athletic, based on the assumption that athleticism correlates with physical traits, the average free-throw percentages in NCAA Division 1 basketball have been close for decades and across gender. The larger men’s basketball could create a disadvantage for men. On the other hand, the stiffer women’s basketball could create a disadvantage for women. In addition, women typically launch the ball from a lower height above the floor than men do. Therefore, the question of which gender is more consistent was unanswered. To answer this question, we turned to simulations of basketball trajectories. We patched together closed-form trajectory events that terminate at the front rim, back rim, backboard, and a fictitious plane below the ring. This produced what we call speed lines. Using the speed lines and NCAA average free-throw percentages, the consistencies of men- and women-free throws were determined. Examination of the speed lines reveals that they exhibit fractal-like behavior. We analyzed sensitivities with respect to ball size, ball bounce, and release height. We found that the most influential factor in determining free-throw success is the average release height of a gender. Under the stipulated assumptions, this paper found that women are about 3% more consistent than men are. 相似文献
3.
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
4.
A rationale and geometric parameters for optimal basketball shooting are provided. The premise is that shots requiring the
least energy are the easiest to control and thus have the greatest probability of success. The kinematics of the ball movement
are modelled and simulated for the free throw, for the direct shot, and for the bank shot off the backboard (the ‘layup’).
For the layup, the analysis includes the effects of friction, ball inertia, ball spin and impact restitution. The results
provide a means for shot planning and for coaching to improve shooting technique. The advantage of the layup for close-in
shooting is demonstrated. Results of numerical parameter studies are also presented, demonstrating the ranges of allowable
shooting error for the various shots, and thus also identifying the shots with highest probability of success. 相似文献
5.
Victor H.A. Okazaki André L.F. Rodacki Miriam N. Satern 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):190-205
The ability to shoot an effective jump shot in the sport of basketball is critical to a player's success. In an attempt to better understand the aspects related to expert performance, researchers have investigated successful free throws and jump shots of various basketball players and identified movement variables that contribute to their success. The purpose of this study was to complete a systematic review of the scientific literature on the basketball free throw and jump shot for the purpose of revealing the critical components of shooting that coaches, teachers, and players should focus on when teaching, learning, practising, and performing a jump shot. The results of this review are presented in three sections: (a) variables that affect ball trajectory, (b) phases of the jump shot, and (c) additional variables that influence shooting. 相似文献
6.
Pedro T. Esteves Pedro Silva Luís Vilar Bruno Travassos Ricardo Duarte Jorge Arede 《Journal of sports sciences》2016,34(16):1557-1563
This study aimed to analyse how youth basketball players explored numerical overloads during shot attempts by measuring their space occupation across specific court areas. Four process-tracing variables measured how the number of attackers (NA), number of defenders (ND), interpersonal distance between attacker and the closest defender (ID) and distance between attacker and the basket (DBkt) impacted on the performance outcome (converted shot; missed shot; ball possession lost). Ten competitive games involving 13 U14 teams were video recorded and players’ displacements were digitised. The associations between performance outcomes and the process-tracing measures were assessed using standardised mean differences and a cross-correlation function. A multinomial logistic regression was used to calculate the odds ratio (OR) for each of the three possible outcomes. Results revealed that when shot attempts occurred at larger ID and at smaller DBkt, the possibilities to obtain a converted shot increased. The numerical overload of defenders near the scoring target was predominantly associated with offensive success. Also, the possibility of attackers to lead the spatial relation of movements with the defenders, near the scoring target, appeared as a prominent strategy to succeed. In sum, basketball teams that exhibit potential to adapt their collective behaviours to local changes in the environment might be closer to achieving successful outcomes. 相似文献
7.
Abstract The purpose of this study was to determine: (a) if preperformance behaviors display a consistent rhythm across disparate activities; and (b) the relationship of periodicity for such preperformance routines to successful performance. Seven male volunteers were subjects for this study. Each subject had an established ritual for golf putt, basketball free throw, and tennis serve. Data were collected with a motion-analysis system and video camera while the subjects performed each activity. Dependent measures were types of preperformance behaviors, absolute timing of behaviors, relative timing of behaviors, differences in relative times across activities, and successful performance, and mechanical variables related to performance. Analysis of variance (Subject x Activity) indicated significant main effects and interactions for absolute and relative timing of behaviors. Significant correlations were determined to exist between relative time and success, and differences were found between relative times across activity and successful performance. It was concluded that rituals result from endogenous rhythms and that stable periodicity of behaviors across activities promotes successful performance. 相似文献
8.
Christopher Ring Maria Kavussanu Ali Al-Yaaribi Gershon Tenenbaum Nicholas Stanger 《Journal of sports sciences》2019,37(8):871-877
Sledging, which is verbal antisocial behaviour in sport, aims to impair an opponent’s performance. Previously, variations in performance have been attributed to changes in emotion and cognition. To improve our understanding of sledging, the current experiment examined the effects of verbal antisocial behaviour on anger, attention and performance. Participants performed a competitive basketball free-throw shooting task under insult (verbal behaviour designed to offend and upset the performer), distraction (verbal behaviour designed to draw attention away from the task), or control (neutral verbal behaviour) conditions. Performance was assessed by the number of successful baskets and a points-based scoring system, while anger and attention were measured post-task. The insult condition provoked more anger than the control and distraction conditions, whereas the insult and distraction conditions increased distraction and reduced self-focus compared to the control condition. Although verbal antisocial behaviour had no overall direct effect on performance, mediation analysis showed that anger indirectly impaired performance via distraction. Implications for the antisocial behaviour-performance relationship are discussed. 相似文献
9.
球的后旋对中远距离投篮作用的探讨 总被引：4，自引：0，他引：4
章运用力学原理，针对球的后旋在中远距离投篮中出现的各种情况进行分析，旨在阐述球的后旋在中远距离投篮中的重要性，以引起有关人士的重视，为在投篮教学和训练中注重球的后旋问题提供理论依据。 相似文献
10.
Rita Ferraz de Oliveira Raôul R. D. Oudejans Peter J. Beek 《Journal of sports sciences》2013,31(9):933-940
Abstract In this study we examined the timing of optical information pick-up in basketball jump shooting using an intermittent viewing technique. We expected shooters to prefer to look at the basket as late as possible under the shooting style used. Seven experts with a high shooting style and five experts with a low shooting style took 50 jump shots while wearing liquid-crystal glasses that opened and closed at pre-set intervals. In principle, under this constraint, the participants could control when they saw the basket by actively modulating the timing of their movements. Analyses of the phasing of the movements relative to the events defined on the glasses revealed that low-style shooters preferred to see the basket just before the ball passed their line of sight, whereas high-style shooters tended to view the basket from underneath the ball after it passed their line of sight. Thus, most shooters preferred to pick up optical information as late as possible given the adopted shooting style. We conclude that, in dynamic far aiming tasks such as basketball jump shooting, late pick-up of optical information is critical for the successful guidance of movements. 相似文献
11.
In this study we examined the timing of optical information pick-up in basketball jump shooting using an intermittent viewing technique. We expected shooters to prefer to look at the basket as late as possible under the shooting style used. Seven experts with a high shooting style and five experts with a low shooting style took 50 jump shots while wearing liquid-crystal glasses that opened and closed at pre-set intervals. In principle, under this constraint, the participants could control when they saw the basket by actively modulating the timing of their movements. Analyses of the phasing of the movements relative to the events defined on the glasses revealed that low-style shooters preferred to see the basket just before the ball passed their line of sight, whereas high-style shooters tended to view the basket from underneath the ball after it passed their line of sight. Thus, most shooters preferred to pick up optical information as late as possible given the adopted shooting style. We conclude that, in dynamic far aiming tasks such as basketball jump shooting, late pick-up of optical information is critical for the successful guidance of movements. 相似文献
12.
Psychometric properties of the Intrinsic Motivation Inventory in a competitive sport setting: a confirmatory factor analysis 总被引：7，自引：0，他引：7
The present study was designed to assess selected psychometric properties of the Intrinsic Motivation Inventory (IMI) (Ryan, 1982), a multidimensional measure of subjects' experience with regard to experimental tasks. Subjects (N = 116) competed in a basketball free-throw shooting game, following which they completed the IMI. The LISREL VI computer program was employed to conduct a confirmatory factor analysis to assess the tenability of a five factor hierarchical model representing four first-order factors or dimensions and a second-order general factor representing intrinsic motivation. Indices of model acceptability tentatively suggest that the sport data adequately fit the hypothesized five factor hierarchical model. Alternative models were tested but did not result in significant improvements in the goodness-of-fit indices, suggesting the proposed model to be the most accurate of the models tested. Coefficient alphas for the four dimensions and the overall scale indicated adequate reliability. The results are discussed with regard to the importance of accurate assessment of psychological constructs and the use of linear structural equations in confirming the factor structures of measures. 相似文献
13.
运用文献资料法、录像观察法、特尔菲法、数理统计法等,对中国男篮与世界强队组织后卫的进攻能力进行比较研究,结果表明：我国组织后卫在得分和投篮次数以及投篮命中率上与对方存在显著性差异,在发动快攻次数以及发动快攻的成功率上与对方具有较大的差距;在个人前场控球次数、控球时间和个人持球进攻次数上高于对方．且无效控球次数和控球时间高于对方;助攻、支配球能力与对方存在明显差距,且失误次数多;组织配合能力差,具体表现在个人持球进攻次数太多,而通过全队配合进攻次数太少;在有球活动区域与对方具有较大的差异。尤其在近区和远区组织配合的成功率上．与对方差距巨大。 相似文献
14.
Steven N. Blair Aaron Blair Henry G. Howe Russell Pate Morton Rosenberg Gwynne M. Parker 《Research quarterly for exercise and sport》2013,84(4):718-723
In this study, the dual-task paradigm was used to determine peak attentional demand during the free-throw process. Thirty participants completed 40 free-throw trials. The free throw was the primary task, but participants also verbally responded to a tone administered at one of four probe positions (PP). Repeated measures analysis of variance showed no significant difference in free-throw performance across PPs, indicating participants were able to keep the free throw as the primary task. Repeated measures analysis of response time (RT) showed significant differences, with RT at PP1 (preshot routine) and PP2 (first upward motion of the ball) significantly higher than baseline RT. These results suggest that PP1 requires the greatest attentional demand, followed by PP2. 相似文献
15.
Three‐dimensional video techniques (50 Hz) were used to obtain images of basketball jump shots from one of three distances ‐ short range (group 1, n = 5); medium range (group 2, n = 5); long range (group 3, n = 5) ‐ from the basket, as performed by members of the men's quarter‐finalist teams at the games of the XVI Universiade in Sheffield in 1991. Fifteen sequences were digitized, beginning 20 frames prior to take‐off to 10 frames after release. To facilitate analysis, the sequences were rotated about the ball position in the final frame so that the shot direction was parallel to one of the pre‐defined orthogonal axes. Mean (+1 s.d.) ball release speed was found to increase with distance from the basket (group 1 = 3.04±0.65 m s‐1, group 2 = 4.71+0.74 m s‐1, group 3 = 6.24 + 0.80 m s‘1), while mean release angles were similar for all groups (group 1=48.8 + 10.1°, group 2 = 47.8 + 5.8°, group 3 = 51.9 + 5.5°). The increased impulse necessary for the ball to reach the basket at increased shooting distances was derived from both an increase in angular velocity of the elbow joint of the shooting arm and an increased velocity of the centre of mass in the direction of the basket at release. Centre of mass speed at take‐off was found to be influenced to a greater extent by the angular velocity of the ankle joint than that of the knee or hip joints. Rotation of the hip and shoulder axes, facilitated by the forward placement of the foot on the side of the shooting arm (antero‐posterior separation values: group 1 = 0.17 + 0.11 m, group 2 = 0.10 + 0.14 m, group 3 = 0.09 + 0.09 m) was utilized by all except one subject. All subjects also used an amount of medio‐lateral foot separation which, along with antero‐posterior separation, promoted stability. All the subjects released the ball while airborne. Both the maximum jump height and the height of the jump at release tended to decrease as shooting distance increased. For short‐range shots, release occurred after the peak of the jump, but increasingly prior to the peak as shooting distance increased. 相似文献
16.
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
17.
普通高校篮球组合技术教学探析 总被引：2，自引：0，他引：2
通过文献资料法、访谈法、实验对照法和数理统计法,对篮球组合技术的教学实验研究表明,以投篮为中心,运球、传接球为基础,对抗练习为手段的教学模式可以提高学生学习积极性和教学效果. 相似文献
18.
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
19.
David R. Hopkins 《Research quarterly for exercise and sport》2013,84(3):535-540
Abstract The purpose of this study was to investigate the factor structure of the sports skill domain of basketball and to identify test items to measure in this skill domain. A theoretical model of the hypothesized dimensions of basketball playing ability was developed based on a review of literature concerning basketball skill testing from 1906 to the present day. These dimensions were: (a) shooting, (b) passing, (c) jumping, (d) movement without the ball and (e) movement with the ball. Twenty-one items, including the nine items in the AAHPER basketball skill test for boys, were selected to sample these hypothesized dimensions. The tests were administered to 70 male junior high and high school students enrolled in the University of Minnesota, Duluth basketball camp during the summer of 1975. The hypothesized dimensions were analyzed by use of the following: (a) alpha factor analysis; (b) canonical factor analysis; (c) image analysis; and (d) principal components analysis. Both oblique and orthogonal rotations were performed with each of the four analyses. The hypothesized model was partially substantiated in that the results confirmed three of the factors: (a) shooting, (b) passing and (c) jumping with the only difference being that the factors of movement with the ball and movement without the ball combined into one. Since the following test items best represented the dimensions, it appeared that a battery comprised of these items would provide a quick and objective measure of basketball skill: (a) jump and reach, (b) dribble, (c) speed pass, and (d) front shot. 相似文献
20.
依据篮球新规则的精神实质及国际篮联发布的相关文件对“24秒”规则和该规则对篮球竞赛影响进行探析，并结合实例得出了“当24秒装置信号发出时，控球队员没有投篮或投篮后球没有触及篮圈才是24秒违例”的结论，以期对今后篮球运动的发展起到良好的推动作用。 相似文献