登陆作战步兵体能训练的思考

步兵在未来登陆作战中最终起着关键性作用。战场环境的特殊性、战场情况的复杂性、战争过程的残酷性，对登陆作战步兵的体能提出了严峻的挑战。从体能面临的新问题入手，就影响步兵体能的专项素质和训练方法进行了分析和探讨，对于解决当前部队训练遇到的问题，提高部队战斗力有很强的参考价值。     

创新驱动视域下国家应用数学中心建设机制研究

通过实地调研与深入访谈,从环境营造、人才引进、科研评价、企业投入等因素深入分析应用数学中心发展建设中存在的瓶颈问题,并提出建立有效沟通与合作机制、探索稳定与多元化投入机制、实行由应用数学家领衔的团队管理机制,以及建立激励应用数学研究落地的评价机制等制度构建与建议.     

自由式滑雪空中技巧运动员不同姿势落地缓冲的生物力学机制研究

自由式滑雪空中技巧项目的落地所受冲击力较大,危险性较高。为减少运动员落地时造成损伤,提高动作的落地稳定性,采用瑞士KISTLER测力台和2台美国TROUBLESHOOTER高速摄像机,同步对6名国家自由式滑雪空中技巧男子运动员在50cm高度下以正常姿势落地和全脚掌落地缓冲实验,分析缓冲时间、标准力值、力值变化梯度、压力中心、人体倾斜角以及下肢关节角度等变化情况。结果表明,50cm高度下最大冲击力全脚掌为正常落地的1.44倍,极有可能造成人体损伤;压力中心前后方向上较小;人体倾斜角较大,说明产生的翻转力矩较小,故稳定性方面较好。     

Do ankle braces provide similar effects on ankle biomechanical variables in subjects with and without chronic ankle instability during landing?

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?.     

竞技蹦床落网缓冲与蹬伸压网阶段矛盾体的力学分析

采用文献资料法、观察法及力学分析法,运用机械能守恒、运动学原理和冲量定理,分析了运动员落网缓冲与蹬伸展体过程。结果发现,入网缓冲前身体姿势的固定,对落网缓冲阶段和蹬伸压网阶段网下降的深度有不同的影响。因而寻求最佳的入网姿势,使落网缓冲和蹬伸压网阶段网下降的深度达到最大值是最追求绝对高度必须解决的一个问题。     

竞技太极拳中32系列难度动作单脚支撑落地稳定性训练探析

基于运动人体科学与运动训练学的相关理论，采用文献分析法、参与观察法、专家访谈法、问卷调查法等研究方法，对竞技太极拳中32系列难度动作落地单脚支撑技术特征进行理论分析和规律探讨。旨在从整体上系统地理解竞技太极拳中32系列难度动作各阶段间的关系，进而准确把握此类动作训练方法设计的理论基础，从而设计科学合理的训练方法，以提高运动员32系列难度动作落地单脚支撑的稳定性。研究得出，可通过SWISS球上俯卧转体等训练提高核心肌群的协调控制能力，BOSU球上单双腿直立或半蹲等练习增强髋关节肌群的离心收缩能力和协调控制能力，仰卧屈膝足跟夹SWISS球、手法松解等方式增强膝关节不同肌群的等长收缩、向心收缩、神经协调控制能力；通过踝关节PNF拉伸、跖趾关节PNF拉伸等增强足底非固有肌离心收缩能力和柔韧性，提高足底固有肌的神经协调能力。     

全国第八届冬运会自由式滑雪空中技巧比赛着陆稳定性浅析

通过对全国第八届冬运会自由式滑雪空中技巧参赛的男女运动员着陆的得分、成功率、稳定性的统计和分析，说明了着陆技术的重要性．在不断提高动作难度的同时应加强着陆稳定性的训练。     

田径教科书中关于短跑途中跑存在问题商榷

在短跑途中跑中，脚着地后髋关节并未弯曲，而是继续伸展：踝、膝关节是被动弯曲，而不是主动弯曲。此刻主动支撑会缩短制动时间，有利于制动冲量的减小。着地缓冲动作的细致划分，对全面正确地认识跑的原理是必要的，着地缓冲阶段应包括前蹬和后蹬的前一部分(垂直部位至最大缓冲)。摆动腿下压动作的作用有重要意义，应引起足够重视，在跑的划分中应有明确的界定。     

基层电大开放教育接轨农村、服务农民的和谐理念

致力于中国农民素质教育是电大系统实施网络教育必须担负的历史使命,基层电大接轨农村、服务农民是开放教育可持续发展的必然趋势。当今农村地区发展的不平衡现状和农民个体活动呈现的独立性、选择性、多变性等形态,决定了各地基层电大在向农村和农民实施开放教育的过程中,必须于教育观念、教育技术以及教育中远期目标上紧紧把持和谐的理念。     

Blocking landing techniques in volleyball and the possible association with anterior cruciate ligament injury

The number and type of landings performed after blocking during volleyball matches has been related to the potential risk of ACL injury. The aim of the present study was to determine whether gender affects the frequency of specific blocking landing techniques with potential risk of ACL injury from the perspective of foot contact and subsequent movement after the block used by volleyball players during competitive matches. Three matches involving four female volleyball teams (fourteen sets) and three matches involving four male volleyball teams (thirteen sets) in the Czech Republic were analyzed for this study. A Pearson chi-square test of independence was used to detect the relationship between gender and different blocking techniques. The results of the present study showed that gender affected single-leg landings with subsequent movement in lateral direction and double-leg landings. Although the total number of landings was lower for male athletes than for female athletes, a larger portion of male athletes demonstrated single leg landings with a subsequent movement than female athletes. Single leg landings with a subsequent movement have a higher potential risk of ACL injury.