排序方式： 共有15条查询结果，搜索用时 31 毫秒
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我国北方具有宝贵资源与先天的气候优势,开展各类冰雪运动的条件充足。冬季的群众性运动数不胜数,撑橇源自于北方民间历史悠久、覆盖地域广阔的“冰爬犁”,是极具民族特色的民间传统体育活动,是我国北方一种特有的民族体育资源,为我国北方民众传承和享用,承载着我国北方民众悠远深厚的冰雪运动文化。农村地广人稀,江河颇多,一到冬季江河结成冰就可以作为撑橇运动的场地,场地充裕,而且撑橇是由黑龙江省体育局批准在黑龙江省率先推广新兴冰上橇类运动,填补了我国世界橇类运动空缺的项目。经调查和研究表明,农村群众性撑橇运动的推广存在着很多制约因素,根据这些制约因素给出相应的解决方案,为更好地推广撑橇运动提供借鉴。 相似文献
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Songning Zhang Michael Wortley Julia Freedman Silvernail Daniel Carson Maxime R. Paquette 《运动与健康科学(英文)》2012,1(2):114-120
PurposeThe purpose of this study was to examine effects of a sport version of a semi-rigid ankle brace (Element?) and a soft ankle brace (ASO) on ankle biomechanics and ground reaction forces (GRFs) during a drop landing activity in subjects with chronic ankle instability (CAI) compared to healthy subjects with no history of CAI.MethodsTen healthy subjects and 10 subjects who had multiple ankle sprains participated in the study as the control and unstable subjects, respectively. The CAI subjects were age, body mass index and gender matched with the control subjects. The arch index and ankle functions of the subjects were measured in a subject screening session. During the biomechanical test session, participants performed five trials of drop landing from 0.6 m, wearing no brace (NB), Element? brace and ASO brace. Simultaneous recording of three-dimensional kinematic (240 Hz) and GRF (1200 Hz) data were performed.ResultsThe CAI subjects had lower ankle functional survey scores. The arch index and deformity results showed greater arch deformity of Element? against a static load than in NB and ASO due to greater initial arch position held by the brace. CAI participants had greater eversion velocity than healthy controls. The ASO brace reduced the first peak vertical GRF whereas Element? increased 2nd peak vertical GRF. Element? brace reduced eversion range of motion (ROM) and peak eversion velocity compared to NB and ASO. In addition, Element? reduced dorsiflexion ROM and increased peak plantarflexion moment compared to NB and ASO.ConclusionResults of static arch measurements and dynamic ankle motion suggest that the restrictions offered by both braces are in part due to more dorsiflexed ankle positions at contact, and higher initial arch position and stiffer ankle for Element?. 相似文献
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在钢琴教学中,强调固定基本手型的同时,随着钢琴作品难度的增加和各种弹奏技术的需要,还应教会学生不断调节手型的开合和屈伸,使他们的两只手从“自然“走向“规范“,最终达到得心应手. 相似文献
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抗震支架可在地震中对建筑机电工程设施给予有效保护,降低震后二次灾害的破环。为探究吊杆对抗震支架抗震性能的影响程度,基于螺杆式抗震支架模型,运用ANSYS Workbench与高性能计算（HPC）技术进行模态分析及反应谱分析。通过研究吊杆直径、吊杆安装长度、吊杆有无紧固C槽钢及紧固C槽钢的安装尺寸4个因素,探究悬吊部分对抗震支架抗震性能的影响程度。研究发现吊杆直径与吊杆安装长度对螺杆式抗震支架悬吊部分性能有较大影响,吊杆处增加紧固C型槽钢可提高吊杆的抗震性能。运用HPC技术进行抗震仿真运算,为ANSYS Workbench与HPC技术在抗震工程中的应用提供范例,也为螺杆式抗震支架的实践应用提供了理论依据。 相似文献
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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
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对于曲柄摇杆机构,在给定行程速比系数K,摇杆摆角ψ的条件下,另外在曲柄长度a、连杆长度b、摇杆长度c、或机架长度d中给定其中两个条件,均可用一个辅助圆简单明了的确定铰链A、B、C、D的位置,从而求出其余构件长度. 相似文献
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