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Abstract The purpose of this study was to examine the mechanics of hitting a baseball to the same and opposite fields. Twenty male subjects were assigned to one of two groups according to their baseball hitting abilities. Each subject performed as many trials as were necessary to successfully hit a pitched ball three times to both the same and opposite fields. Each trial was filmed from above. No significant interactions (p < 0.05) were found between subject groups and field hits with selected temporal and kinematic parameters entered as dependent variables. Significant differences (p < 0.05) were found between body landmark and segment component displacements and velocities at the instant prior to ball contact. The maximum resultant linear and angular speed of the examined body and bat landmarks were found to occur prior to ball contact. Based on the results of the study it was concluded that no interactions exist between hitting ability and hitting technique when hitting to defined field areas and that differences in the mechanics of hitting to defined areas are due in part to: (1) differences in the angular displacements of the left wrist and left elbow joints and (2) differences in the temporal characteristics of the swings. 相似文献
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郭炎林 《山西师大体育学院学报》2010,25(6):120-122
在棒垒球运动中慢速垒球简化了规则,降低了技术难度,是一种适合大众开展的健身性运动休闲项目。通过调查发现高校学生掌握棒垒球知识很少,但是通过简单易学的慢速垒球运动,可以尽快地使学生体验到棒垒球运动的魅力,了解到棒垒球运动的文化内涵。同时,从高校目前场地建设与教师队伍的实际出发,慢速垒球更加适合推广与发展。另外,慢速垒球适合在高校开展竞赛活动,通过竞赛的杠杆作用可促进棒垒球运动在高校的普及与提高。 相似文献
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Rainer Martens Francine Rivkin Linda A. Bump 《Research quarterly for exercise and sport》2013,84(4):351-355
Abstract Nine- to 10-year-old children have difficulty playing baseball using adult rules because pitchers lack the ability to throw the ball over the plate with consistency and batters lack ability to hit erratically thrown balls. Thus a natural field experiment investigated a modification of adult baseball for 9- to 10-year-old children. Instead of one of the players on the opposing team pitching, the coach of the offensive team pitched to the batters. Teams in a league who played baseball by adult rules (traditional league) were compared with teams in a league who played the modified game (nontraditional league), and both these leagues were compared with 11- to 12-year-old teams (older league). Various offensive and defensive activities were recorded by two observers and satisfaction scores were obtained from the players after the games. More offensive and defensive activity occurred in the nontraditional league games than in the traditional and older league games. 相似文献
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Karen E. French John H. Spurgeon Michael E. Nevett 《Research quarterly for exercise and sport》2013,84(3):179-188
Abstract The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight of the twelve teams participating in the 1995 Dixie Youth World Series. Normative data for the United States (NCHS) were used as comparative data. Two trained anthropometrists measured standing height, sitting height, lower limb height, upper limb length, arm girth, calf girth, tricep skinfold, and abdomen skinfold on all participants. In both samples, pitchers, short stops, and first basemen were a more highly skilled group and exhibited larger body size (greater standing height, sitting height, lower limb height, upper limb length) than children who played at other positions. The standing height of local little league players was similar to the median of reference data at ages 7, 8, and 9 years. The standing height and weight of skilled players in both samples approximated the 75th percentile for standing height and weight at ages 10, 11, 12, and 13 years. The results suggest that baseball players exhibit larger body size than the normal population at young ages. Body size may be an important criterion used by coaches to select and assign young players to certain positions. 相似文献
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Alexander V. Melnikov Robert N. Singer 《Research quarterly for exercise and sport》2013,84(4):400-405
Abstract The purpose of this study was to examine how one secondary physical education teacher understood gender at her school and how that understanding developed. Theoretical perspectives on feminism and the nature of teachers' knowledge guided the inquiry. Data were collected through 20 teacher observations and 60 interviews over 4 months and analyzed using constant comparison with frequent member checks to facilitate accuracy. Three main findings emerged. First, this teacher identified two aspects of the broader school culture, which she believed sent students, particularly girls, gendered and patriarchal messages of social positions. Second, she described a number of practices in the traditional physical education program, which she believed contributed further to girls' disempowerment. Finally, this teachers' stance in the political structure of the school both constrained and enhanced the development of her understanding of gender. Findings are discussed in relation to feminist theoretical stances and feminist teacher knowledge development. 相似文献
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This article explores the growth of Chinese baseball since the early 1970s. The sport was very popular in the 1940s and 1950s as the semi-official pastime of the People's Liberation Army, but it disappeared from the country in the 1960s due to economic woes stemming from the Great Leap Forward and the anti-western fervour of the Cultural Revolution. Richard Nixon's historic meeting with Chairman Mao in 1972 ushered in a thaw in Sino–American relations that enabled veterans of 1950s competitions to take up baseball once again and teach the game to a new generation. Over the 1970s, baseball began to slowly grow in China with some modest Japanese encouragement and China began competing internationally the following decade. Over the past decade, Major League Baseball has made such a large investment in China that baseball has become the fastest growing sport in the country. At present, the country's only professional league is currently in the early stages of its development, but American talent evaluators believe that the skill of Chinese players is steadily improving and that it is not impossible to foresee a day when China produces baseball's Yao Ming from a massive pool of millions of internationally competitive athletes. 相似文献
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影响我国高校棒球运动开展的因素与对策分析 总被引：5，自引：0，他引：5
运用文献资料、专家访谈、比较分析等研究方法，对我国高校开展棒球运动的现状进行分析。研究发现：正在开展棒球运动的高校在全国各地区分布不均衡，大部分集中在沿海和中部地区；而且各个高校开展棒球运动目的、组织形式等也不相同；导致这种现象的主要原因是全国大部分高校开展棒球运动的资金匮乏、全国性棒球比赛少而且缺乏影响力等；针对这些问题，提出了几点建议，以便促进我国棒球运动的开展与普及。 相似文献
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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