竞技武术套路中腾空摆莲B 和C 级跳跃落地稳定性的研究 杨乃

竞技武术套路中腾空摆莲B和C级跳跃落地接马步是长拳、南拳武术项目的两个难度动作.通过对该组动作落地技术的动力学及相关稳定性因素的分析,提出合理的落地技术和训练中需解决的问题.采用录像观察与试验分析相结合的方法,针对男女运动员的腾空与落地的特点,提出相应的解决办法和训练理论.     

运动疲劳对大鼠海马CAI 区神经元电活动的影响

目的：通过神经电生理学的方法,揭示运动性中枢疲劳的神经生物学机制。方法：30只健康雄性sD大鼠,随机分为安静对照组（CG）、有氧运动组（AG）和运动疲劳组（FG）。采用微电极技术在体观察运动训练后大鼠海马CAI区神经元自发及诱发电活动的变化规律,并通过被动回避行为条件反射的方法观察大鼠的学习记忆能力。结果：FG组大鼠海马神经元的自发和诱发电活动均显著低于CG组和AG组（P〈0.05）。FG组学习记忆能力显著低于CG和AG（P〈0.05,P〈0.01）。结论：运动疲劳可抑制大鼠海马神经元的兴奋性,并降低其学习记忆能力。提示：海马神经元自发放电频率与学习记忆能力有密切关系,运动疲劳导致海马神经元电活动的变化可能是其学习记忆能力降低的机制之一。     

我国优秀男子射箭运动员体能评价

通过专家访谈法、现场测试法、数理统计法,对我国当前现役优秀男子射箭运动员体能现状评价。研究认为,我国优秀男子射箭运动员的体能测试指标为：卧推、转肩、拉弓停时、负重快速连续下蹲、杠铃前平举、背起、引体向上、跳绳、手指俯卧撑、两头起、12min跑;建立了优秀男子射箭运动员体能模型。结论：影响我国优秀男子射箭运动员的体能成绩主要因素及其程度依次为：X3为胸部力量因子,X1为腰背柔韧性与手指力量因子,X2为肩背力量因子,X4为耐力因子;我国优秀男子射箭运动员需要加强的是肩背部力量、肌肉耐力、核心力量、腿部力量以及肩部柔韧性。     

江苏省农村居民体质健康水平的比较研究

目的：了解江苏省不同地区农村居民的体质健康现状,把握2000年到2005年农村居民体质水平的变化趋势。方法：采用卡方检验,比较不同年份和地区的体质等级水平情况,使用方差分析、t检验比较年份、地区的体质总分改变情况。结论：苏南地区农村居民体质水平变动不大,苏中有明显改善,但不合格率仍处于较高水平,苏北的体质水平整体有所下降。为加快社会主义新农村建设,应加强农村居民体育锻炼,做好农村居民体质水平宣教工作,全面提高农民素质。     

体育课运动技能获得的教学实验——加速运动技能获得的新方法简介

本实验利用人为强化本体感受反馈的原理探讨一种新的加速运动技能获得的方法？实验参加青在电脑屏幕前用鼠标追踪电脑屏幕上一个移动的光点,移动光点按预定的程序作曲线运动另一子程序按每秒一百次的频率自动扫描移动光点与追踪鼠标点之间的距离,每轮追踪结束后自动计算出该轮扫描误差的标准差,移动光点与追踪鼠标点之间的距离越小,追踪误差越小随着练习次数及练习天数的增加,追踪误差会越来越小。我们发现,在保证运动连续性的条件下最大限度地增强与运动相关的主动肌、对抗肌、协同肌及支持肌自身紧张度可以加速运动技能的获得。     

全球化语境下东西方体育文化的阐释

任何一个民族的体育文化既不可能完全是本民族的文化,也不可能全部是外来文化。体育文化通过现代传播媒介、竞争意识、交往需要、人的本质属性、文化帝国主义以及体育文化本身的通约性演绎着全球化。民族体育文化的独特性、历史性和差异性既确保民族体育文化的特色,同时也制约着民族体育文化的开放程度。     

奥运会承办国家的国际环境分析

通过对奥运会承办国家含义及奥组委特征的描述,分析了奥运会承办国家的国际环境,包括政治、经济、安全、文化等多方面。并对这些环境做了利弊的分析,提出了奥运承办国家对待国际环境的态度与对策。     

Pedometer reliability, validity and daily activity targets among 10- to 15-year-old boys

The aims of this study were to: (1) determine whether the number of pedometer counts recorded by adolescents differs according to the adiposity of the participant or location on the body; (2) assess the accuracy and reliability of pedometers during field activity; and (3) set adolescent pedometer-based physical activity targets. Seventy-eight 11- to 15-year-old Boy Scouts completed three types of activity: walking, fast walking and running. Each type was performed twice. Participants wore three pedometers and one activity monitor during all activities. Participants were divided into groups of normal weight (BMI < 85th percentile) and at risk of being overweight (BMI > or = 85th percentile). Intra-class correlations across the three activities indicated reliability (r = 0.51 - 0.92, P < 0.001). This conclusion was supported by narrow limits of agreement that were within a pre-set range that was practically meaningful. Multivariate analysis of covariance indicated adiposity group differences, but this difference was a function of the increased stature among the larger participants (P < 0.001). Ordinary least-squares regression models and multi-level regression models showed positive associations between the number of pedometer and activity monitor counts recorded by the three groups of participants during all activities (all P < 0.001). The mean number of counts recorded for all participants during the fast walk was 127 counts per minute. In conclusion, the pedometers provided an accurate assessment of adolescent physical activity, and a conservative estimate of 8000 pedometer counts in 60 min is equivalent to 60 min of moderate to vigorous physical activity.     

The energetics and benefit of an arm swing in submaximal and maximal vertical jump performance

The aims of this study were to investigate the energy build-up and dissipation mechanisms associated with using an arm swing in submaximal and maximal vertical jumping and to establish the energy benefit of this arm swing. Twenty adult males were asked to perform a series of submaximal and maximal vertical jumps while using an arm swing. Force, motion and electromyographic data were recorded during each performance and used to compute a range of kinematic and kinetic variables, including ankle, knee, hip, shoulder and elbow joint powers and work done. It was found that the energy benefit of using an arm swing appears to be closely related to the maximum kinetic energy of the arms during their downswing, and increases as jump height increases. As jump height increases, energy in the arms is built up by a greater range of motion at the shoulder and greater effort of the shoulder and elbow muscles but, as jump height approaches maximum, these sources are supplemented by energy supplied by the trunk due to its earlier extension in the movement. The kinetic energy developed by the arms is used to increase their potential energy at take-off but also to store and return energy from the lower limbs and to "pull" on the rest of the body. These latter two mechanisms become more important as jump height increases with the pull being the more important of the two. We conclude that an arm swing contributes to jump performance in submaximal as well as maximal jumping but the energy generation and dissipation sources change as performance approaches maximum.     

Acknowledgements

Acknowledgement

Acknowledgements