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81.
我国优秀棒球投手上肢运动的检测分析 总被引：2，自引：0，他引：2
目的:以探讨棒球投手肩关节旋转运动特征.方法:通过应用一种超声波动力学测量仪和等速仪器分别对25名棒球投手和25名自愿者肩关节内、外旋活动范围(range of motion,ROM)、内外旋肌力进行测量.结果:棒球投手优势臂的外旋活动范围明显大于非优势臂,而其优势臂的内旋活动范围则显著小于非优势臂,优势臂的整个旋转活动范围也明显比非优势臂小;对照组的优势臂和非优势臂旋转活动范围差异无显著性,棒球投手肩关节存在内、外旋肌力不平衡,实验组优势臂内旋IR(210°/s)、IR(300°/s)相对峰力矩明显大于非优势臂(P＜0.001),优势臂外旋ER(210°/s)、ER(300°/s)峰力矩与非优势臂相比,无明显差异(P＞0.05),实验组优势臂外旋/内旋峰力矩比值(ER/IR)明显小于非优势臂. 相似文献
82.
人格特征对棒球运动员运动损伤的影响 总被引：10，自引：1，他引：9
以应激—运动损伤理论(Williams&Andersen,1998)为依据,以棒球运动员为研究对象,以艾森克人格问卷为人格测量工具,以经过翻译并修订的《运动员生活事件量表》为应激经历的测量工具,采用二项logistic回归分析(后退法)法,考察了人格特征对运动员运动损伤的影响效应。结果显示:内外向、消极事件、消极事件与内外向的交互作用3个变量的OR值分别为5.020(P<0.05)、3.035(P<0.05)、0.925(P<0.05)。这表明运动员越趋外向、承受的消极生活应激量越大,则发生急性运动损伤的可能性就越大;运动员在内外向上的特质与所承受的消极生活应激量对急性运动损伤的发生产生了交互作用。 相似文献
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我国高校开展棒垒球运动的可行性分析及其对策研究 总被引：1，自引：0，他引：1
采用文献资料法、逻辑分析法，以2008年北京奥运会和高校全面推进素质教育为契机，提出普及和提高棒垒球运动应该以高校为切入点，对我国高校开展棒垒球运动的可行性从项目和学生特点、学校体育教育改革、设施、师资方面进行分析，并提出相应发展对策。 相似文献
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Amber L. Griffioen 《体育哲学杂志》2013,40(3):327-348
In 2010, pitcher Armando Galarraga was denied a perfect game when umpire Jim Joyce called Jason Donald safe at first with two outs in the bottom of the 9th. In the numerous media discussions that followed, Joyce’s ‘blown’ call was commonly referred to as ‘mistaken’, ‘wrong’, or otherwise erroneous. However, this use of language makes some not uncontroversial ontological assumptions. It claims that the fact that a runner is safe or out has nothing to do with the ruling of the umpire himself, but rather with some state of the universe that does not depend on the umpire for its existence (e.g. the runner’s reaching the base before the ball or not). In this paper, I recast the problem as a version of Plato’s Euthyphro Dilemma and argue that the view implied by the above assertions is actually misguided. Instead, I hope to show that an alternative view – what I call ‘restricted umpire voluntarism’ – is actually more in line with the spirit of the game of baseball and is not as counterintuitive as it may appear at first glance. 相似文献
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Hillary Plummer 《Journal of sports sciences》2013,31(10):1108-1116
Abstract The catcher has the most demanding position in the games of baseball and softball with no regulations on how many throws they make during game. It was the purpose of this study to describe the kinematics and kinetics of the throwing motion in catchers when throwing down to second base. It was hypothesised that younger and older catchers would display significantly different throwing kinematics and kinetics. Thirty-eight baseball and softball catchers volunteered to participate. Twenty participants were considered younger (aged 9–14, 10.95 ± 1.76 years, 151.11 ± 15.64 cm, 47.94 ± 18.84 kg) and 18 were deemed the older group (aged 15–23, 18.11 ± 2.61 years, 170.91 ± 8.67 cm, 74.88 ± 10.74 kg). Participants received a pitch and completed five accurate throws to second base in full catching gear. The average ball speed of the older catchers was 21 ± 3.58 meters per second (47 ± 8.02 mph) while the younger catchers averaged 17.2 ± 4.0 meters per second (38.6 ± 8.96 mph). Older catchers had greater shoulder elevation at ball release and significantly greater shoulder external rotation at foot contact and shoulder maximum external rotation than younger catchers. It is clear that chronological age plays a role in the throwing mechanics observed in catchers throwing down to second base, however the effects of these differences are not fully understood (i.e., skeletal maturity, experience, strength). 相似文献
86.
多年以来,运动史学家都在争论,何以棒球能在曾为大英帝国殖民属地的美国取得凌驾于板球的发展。板球在美国的迅速式微,无论对于棒球或板球研究来说,都堪称最令人困惑的问题之一。及至今日,棒球与板球关系背后仍然存在许多难解的问题。既有文献指出,板球在美国的发展不仅可以上溯至17世纪,直到1860年代,板球也仍为美国非常普及的运动;但吊诡的是,就在内战之后,当美国社会进入"镀金时代"之后,板球却逐渐式微,甚至沦为美国边缘运动。透过检视美国棒球与板球发展的历史,本文企图指出主流理论的问题,尝试针对美国棒球与板球发展消长的关系提供不同的解释。 相似文献
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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
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Professional baseball players have attempted to illegally modify baseball bats in the hopes of increasing bat speed and thus
the distance travelled by batted balls. To date, no low-cost, non-invasive, real-time solution exists to this problem. Previously
proposed solutions to this problem that involved using radar to measure the scatter signature of a scanned baseball bat were
found to be extremely expensive. Ultrasound technology offers the ability to provide equivalent scatter signature measurements
as compared to radar technology at a much lower cost and level of complexity while still operating in real time. We therefore
present an ultrasound-based implementation of a prototype for a hand-held scanner unit designed to detect illegally modified
baseball bats. A detailed discussion of the performance enhancements resulting from illegally modifying a baseball bat will
be provided and an analysis of the attenuative properties of wood will be presented to determine appropriate sample rates
for the ultrasound unit. Data acquisition issues encountered in prototyping the scanner will be examined and measurement data
for both solid wood bats and modified bats will be evaluated to determine the effectiveness of the ultrasound-based data acquisition
unit and the prototype’s ability to distinguish between both types of scatter signatures. 相似文献