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1.
中国棒球运动员的挥击技术水平急待提高，改进的途径是改变传统的挥击技术理论与方法，采用新的挥棒发力机制，在技术上强调上臂运端环节肌肉的主动用力，以准确统一速度。在具体打法上为运动员在来球距本垒板前３．４ｍ左右时开始下棒；挥棒时间小于０．１２ｓ，身体重心垂直位移近似零，屈臂状态下击中球；中球瞬间，腕关节未呈翻腕状态。 相似文献
2.
棒球挥击动作技术的核心是快速有力和准确这两个因素。而过去的几十年里,人们一直把快速有力放在第一位。同时,挥击技术上主要采用田径投掷项目的技术原理。笔者在教学和训练中认为以上两点在理论和技术上都较为不妥。笔者通过实验,改进上肢动作,改变发力结构,以寻求更快,更准的挥击效果,为探索一种新的挥击动作而提供理论依据。 相似文献
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本文通过对我国部分优秀棒球选手的挥击动作运动学和动力学的分析，力图描述出我国棒球选手目前挥击动作中髋、肩、腕等关节的运动状态和它们与甜点之间协调制约的关系，以及挥击技术动作中上述有关环节及时制动的生物力学原理及其应用价值。 相似文献
4.
本研究力图将理论研究与实践运用相结合起来,走从理论到实践运用再上升理论的研究思路。为此,我们在运用高技术手段对高水平运动是进行综合研究之后,分别将这些成果应用于专业队与非专业队的训练,在实践修正的基础上,对挥击技术的动作外形、技术参数,击打意识与技术概念进行了总结,力求使技术成果真正可操作,易理解和简单实用 相似文献
5.
过去，我国对两个高速相向运动的球棒和球瞬间外碰撞粘滞时间的定量近似值没有进行科学研究．揭示这个粘滞时问的定量近似值，能给击球远而有力有所启示．首次在我国采用先进的美国ＫＯＤＡＫＥＫＴＡＰＲＯ１０００帧／ｓ高速录相分析系统进行５００帧／ｓ的水平和垂直同步拍摄击球全过程．解析得出粘滞时间４ｍｓ（毫秒）定量近似值．为提高中国挥击能力须对实验依据不足的挥速理论予以纠正． 相似文献
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棒球运动中挥棒击球时球与棒接触点的选择是打击中心原理的一个应用实例。这里挥击技术要求回答的问题有两个:一是让球触在何处才能使握棒的手不受振动和刺痛;二是让球触在何处才能使所用的力量充分“贯注”到球上。一般力学和物理学书籍中 相似文献
8.
击响脚过肩是构成竞技武术套c组难度动作的重要一环。文章运用对比分析法、理论分析法、运动生物力学测试法对324c＋1难度动作进行研究,结果表明：击响的时间是影响324c＋1完成转体度数主要因素之一;起跳角、击响时刻膝角、髋角大小影响击响脚过肩;起跳脚大不利于减小完成击响时间;击响时刻膝角、髋角小不利于脚过肩;击响时刻最佳的躯干角、髋角是击响脚过肩且腿不高踢的保证。 相似文献
9.
通过观察上海女子垒球队的训练以及全国垒球联赛,再结合自身的经验,在挥击直线快球和变化球的下肢及转体动作,有许多相同点也有它们之间的区别。下面我们就具体进行分析它们的共同点与区别以及容易出现的错误动作。1、挥击内角直线快球的下肢及转体动作在挥击内角直线快球的动作中,主要强调的是一个＂快＂字。是指腰部及下肢的蹬地转体动作要快。 相似文献
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11.
Rob Gray 《Research quarterly for exercise and sport》2013,84(3):491-501
Bat/ball contact produces visual (the ball leaving the bat), auditory ( the “crack” of the bat), and tactile (bat vibration) feedback about the success of the swing. We used a batting simulation to investigate how college baseball players use visual, tactile, and auditory feedback. In Experiment 1, swing accuracy (i.e., the lateral separation between the point of contact and “sweet spot”) was compared for no feedback (N), visual alone, auditory alone, and tactile alone. Swings were more accurate for all single-modality combinations as compared to no feedback, and visual produced the greatest accuracy. In Experiment 2, the congruency between visual, tactile, and auditory was varied so that in some trials, the different modalities indicated that the simulated ball contacted the bat at different points. Results indicated that batters combined information but gave more weight to visual. Batting training manuals, which typically only discuss visual cues, should emphasize the importance of auditory and tactile feedback in baseball batting. 相似文献
12.
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent,
the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis
on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege
baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets,
balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured
speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical
axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical
model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of
the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation
axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest
the importance of additional degrees of freedom in determining swing speed. 相似文献
13.
This study addressed the question, what should baseball players focus their attention on while batting? Less-skilled and highly skilled (college) baseball players participated in four dual-task conditions in a baseball batting simulation: two that directed attention to skill execution (skill/internal [movement of the hands] and skill/external [movement of the bat]) and two that directed attention to the environment (environmental/irrelevant [auditory tones] and environmental/external [the ball leaving the bat]). Batting performance for highly skilled players was best in the environmental/external condition and worst in the skill/internal condition. Performance of less-skilled batters was significantly better in the two skill conditions than in either of the two environmental conditions. We conclude that the optimal focus of attention for highly skilled batters is one that does not disrupt proceduralized knowledge and permits attention to the perceptual effect of the action, whereas the optimal focus of attention for less-skilled batters is one that allows attention to the step-by-step execution of the swing. 相似文献
14.
棒球运动是以击球跑垒、跑垒得分的进攻行为与投球、接传球的防守行为相对抗为特点的运动项目.在棒球比赛中,投手的球投得好,就能控制击球员的击球,全面控制对方的进攻.因此投手投球的技术战术和心理战术起着十分关键的作用,决定了全局的比赛.通过结合近年来国内、外学者对棒球投手的运动生物力学研究成果,探讨投手投球技术战术及技术战术... 相似文献
15.
NORIYUKI TABUCHI TOMOYUKI MATSUO KEN HASHIZUME 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):17-30
The aims of this study were to examine whether batters hit stationary balls at the time of peak speed of the bat head and whether the impact occurs at the lowest point of the bat trajectory. Eight university baseball players hit three balls, each hung with a string; each ball was made of a different material and was different in weight. Bat movement was captured by four 240-Hz infrared cameras and analysed three-dimensionally. Time for peak speed of the bat head varied according to the conditions. When stationary balls of standard weight were used, the bat head was at maximum speed at impact with the ball; then, it decelerated drastically owing to the impact. In contrast, maximum speed was obtained after impact when lightweight stationary balls were used. The time–speed profile of the bat head before impact in the lightweight ball condition was identical with that in the standard weight ball condition. Regardless of conditions, the timing of the lowest point of the bat head was nearly identical for each batter and most participants hit the stationary balls at about the lowest point of the bat trajectory 相似文献
16.
Tabuchi N Matsuo T Hashizume K 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(1):17-30
The aims of this study were to examine whether batters hit stationary balls at the time of peak speed of the bat head and whether the impact occurs at the lowest point of the bat trajectory. Eight university baseball players hit three balls, each hung with a string; each ball was made of a different material and was different in weight. Bat movement was captured by four 240-Hz infrared cameras and analysed three-dimensionally. Time for peak speed of the bat head varied according to the conditions. When stationary balls of standard weight were used, the bat head was at maximum speed at impact with the ball; then, it decelerated drastically owing to the impact. In contrast, maximum speed was obtained after impact when lightweight stationary balls were used. The time-speed profile of the bat head before impact in the lightweight ball condition was identical with that in the standard weight ball condition. Regardless of conditions, the timing of the lowest point of the bat head was nearly identical for each batter and most participants hit the stationary balls at about the lowest point of the bat trajectory. 相似文献
17.
Brittany Dowling Glenn S. Fleisig 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(3):255-269
Determining and understanding baseball batting mechanics at various competition levels may help players and coaches identify key kinematics crucial to being a successful hitter. The purpose of this study was to compare batting kinematics across competition levels. Kinematic and temporal data were analysed for 170 male batters (youth n = 33; high school n = 69; college n = 22; professional n = 46) using 3D motion capture (480 Hz). The results showed differences in angular positions between competition levels during the five phases of the swing, with the greatest differences seen between the youth and professional batters. At the instant of ball contact, professional batters held the bat farther away from their body, with greater back shoulder abduction (35°) and less back elbow flexion (78°) compared to youth (27° and 89°, respectively). These differences were associated with greater back elbow extension velocity for professionals (1539°/s) compared to youth (1174°/s). Additionally, higher level batters had higher bat angular and linear velocities compared to the youth batters. As batters progress through their career, they should focus on their back arm by keeping their elbow up and their arm extended in front of them. 相似文献
18.
Hitting a major league fastball, with approximately half a second to react, poses one of the greatest challenges in sports.
The ability to hit the ball derives from the dynamics of the bat swing which can be measured using video motion capture. However,
doing so necessitates swinging the bat within the confines of a motion capture laboratory, often with considerable time and
expense. This paper introduces an inexpensive and highly portable measurement method for use right on the field of play to
support player training, coaching, rehabilitation, and player-bat fitting. The method employs a highly miniaturized, wireless
MEMS inertial measurement unit (IMU) affixed to the knob of the bat. The IMU incorporates three-axis sensing of bat acceleration
and angular velocity with a low-power RF transceiver to transmit this data to a host computer. Analysis of this data yields
a near-instantaneous and highly resolved summary of three-dimensional bat dynamics. This paper describes this novel technology
for use in baseball and softball, presents example results, and reveals new features of bat motion overlooked in previous
studies. 相似文献
19.
Walter A. Laughlin Kyle T. Aune Alek Z. Diffendaffer 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(1):36-47
Swing trajectory and ground reaction forces (GRF) of 30 collegiate baseball batters hitting a pitched ball were compared between a standard bat, a bat with extra weight about its barrel, and a bat with extra weight in its handle. It was hypothesised that when compared to a standard bat, only a handle-weighted bat would produce equivalent bat kinematics. It was also hypothesised that hitters would not produce equivalent GRFs for each weighted bat, but would maintain equivalent timing when compared to a standard bat. Data were collected utilising a 500 Hz motion capture system and 1,000 Hz force plate system. Data between bats were considered equivalent when the 95% confidence interval of the difference was contained entirely within ±5% of the standard bat mean value. The handle-weighted bat had equivalent kinematics, whereas the barrel-weighted bat did not. Both weighted bats had equivalent peak GRF variables. Neither weighted bat maintained equivalence in the timing of bat kinematics and some peak GRFs. The ability to maintain swing kinematics with a handle-weighted bat may have implications for swing training and warm-up. However, altered timings of kinematics and kinetics require further research to understand the implications on returning to a conventionally weighted bat. 相似文献
20.
Clayton T. Shay 《Research quarterly for exercise and sport》2013,84(3):433-437
Abstract Reaction time of the batter in Softball is important because of short pitching distance and the speed of the pitcher. Nine pitchers were tested for speed and had an average velocity of 59.95 mph and a mean reaction time of .215 sec. was found for 258 students tested. With these averages, the ball would be 29.33 ft. from home plate before 116 of these students began their swing and in 41 cases the ball would be less than 20 ft from the plate. Pitchers with greater velocity would decrease the success of the batter if the reaction time remains the same. 相似文献