优秀速滑运动员弯道滑跑与陆上模拟肌电特征及其对训练的启示

目的:通过对优秀速滑运动员冰上弯道滑跑和陆上模拟训练肌肉用力特征的对比研究,为提高陆上训练的专项性提供科技支撑。方法:以奥运冠军张虹为研究对象,采用视频与肌电同步技术采集冰上与陆上肌电参数,从做功的主要肌群、肌肉激活强度和肌肉激活顺序3个方面,对弯道滑跑肌肉用力特征及陆上模拟训练的专项性进行分析。结果:张虹胫骨前肌和股前肌群是冰上支撑阶段的主要做功肌群;胫骨前肌自收腿起至着冰止,处于持续发力状态,蹬冰时灭活;股前肌群着冰前处于激活状态,收腿阶段灭活;胫骨前肌激活程度屈过程大于伸过程,股前肌群激活程度伸过程大于屈过程;陆上模拟肌肉用力特征与专项有一定差异,但对股前肌群有较好的训练作用。结论:冰陆间肌电的差异是由于支撑条件与方式不同引起的,根据专项技术的特殊需求,对训练器材进行适当改造和对训练细节进行完善,可进一步加强训练的专项化程度,提高训练效益。     

我国部分优秀男子跳远运动员起跳环节肌肉用力特征

通过表面肌电遥测和高速摄影同步测试,揭示优秀跳远运动员起跳环节肌肉用力特征.结果显示:在起跳环节中,股外侧肌、股内侧肌、股二头肌、比目鱼肌、腓肠肌是起跳腿的主要用力肌肉;在起跳腿即将着地前,所测肌肉均有较明显的预激活现象;着地后,肌肉用力的激活顺序依次为胫骨前肌、股二头肌与股内侧肌、股外侧肌、比目鱼肌、腓肠肌内侧头、股直肌、臀大肌;肌肉用力的失活顺序依次为胫骨前肌、股直肌、股内侧肌、股外侧肌、臀大肌、腓肠肌、股二头肌、比目鱼肌;肌肉用力持续时间长短依次为股二头肌、比目鱼肌、股外侧肌、腓肠肌内侧头和股内侧肌、臀大肌、股直肌、胫骨前肌.起跳腿拮抗肌共同收缩的特征为:缓冲阶段踝关节拮抗肌共同收缩最强烈,而在蹬伸阶段膝关节拮抗肌共同收缩最强烈.     

我国女子速度滑冰运动员冰陆专项力量练习主要工作肌肉特点的比较研究

利用肌电图测试技术测试分析我国两名优秀女子短距离速滑运动员冰上过程中以及主要陆上专项力量练习动作下肢主要肌肉的用力规律,通过对比分析确定我国两名女子重点运动员速滑过程和陆上专项力量练习的肌肉发力特点,指出陆上专项力量练习与实际速滑过程中肌肉用力特点的差异,进而对陆上专项力量训练提出相关建议,旨在为教练员和运动员提高专项力量训练质量提供参考。     

我国优秀双人滑男运动员落冰及模仿训练肌电特征研究

目的：探讨花样滑冰跳跃动作落冰过程中肌肉的工作特征及相关陆地模仿的训练效果。方法：以我国优秀双人滑男运动员张某为研究对象,利用 Mega ME6000肌电测试仪对其完成后外点冰两周跳、陆地两周跳、凳上跃起动作落地过程支撑腿落地后0.8 s内双侧胫骨前肌、腓肠肌外侧头、股直肌、股二头肌、臀大肌、竖脊肌、腹外斜肌和腹直肌的表面肌电信号进行采集,通过MegaWin2.4对原始数据进行处理分析。结果：完成专项动作时积分面积较大的8块肌肉依次为右侧股二头肌、右侧股直肌、右侧腓肠肌外侧头、左侧股二头肌、右侧胫骨前肌、右侧臀大肌、左侧臀大肌和右侧竖脊肌,多数工作肌的积分肌电峰值出现在落冰后的0.4 s左右;完成专项动作各肌肉积分面积与凳上跃起动作具有较高相关性（r=0.578,P=0.019）,与 陆地两周跳动作不相关;肌肉贡献度较大的肌肉中,专项动作与两种陆地模仿动作相比,支撑腿股二头肌、股直肌和腓肠肌外侧头的平均积分肌电 值明显偏高,积分肌电峰值出现时间不同。结论：完成后外点冰两周跳落冰动作的主要工作肌为支撑腿各肌群、同侧竖脊肌及摆动腿的股二头肌、臀大肌;凳上跃起和陆地两周跳两种陆地模仿练习的肌肉工作特征与专项动作有一定差异,可作为辅助训练手段,但不宜过多采用。     

我国优秀速度滑冰运动员途中滑跑腿部肌肉肌电特征研究

运用表面肌电和高速摄影同步技术,结合功能解剖学,分析王北星途中滑跑单步周期腿部肌电特征,进行技术诊断。结果表明：（1）王北星左腿力量大于右腿符合速滑项目特征,但左腿支撑时重心高于右腿,说明左腿仍属弱势腿;（2）王北星胫骨前肌是踝关节运动主要用力肌肉,是单步周期主要用力肌肉之一,摆动期出现多余放电;（3）王北星蹬冰期股四头肌和股后肌群肌电振幅呈双峰现象,股内肌、股外肌、股二头肌和半腱肌是主要用力肌肉;（4）王北星左右腿蹬冰期蹬冰肌群肌肉用力方式不一致。教练组应根据王北星腿部肌电特征,有针对性的设计训练方法。     

优秀速滑运动员于静直线等速蹬伸肌力特征及sEMG研究

目的:探讨支撑方式、支撑条件、动作速度和动作过程对下肢最大肌力和做功能力的影响,为专项力量练习手段的选择和设计提供理论参考.方法:采用视频、表面肌电和直线等速运动同步对于静蹬伸过程中的力学和肌电参数进行研究.结果:1)支撑条件和支撑方式对下肢力和做功有非常显著性影响.有冰刀支撑时最大肌力和做功小于无冰刀支撑,单腿支撑力与功小于双腿支撑,两单腿支撑力与功的和大于双腿支撑;2)速度和动作过程对下肢力和做功有非常显著性影响.离心蹬伸时,速度大则力量与做功都大,而向心时速度大则力量与做功都小;同一速度下,等速离心收缩的最大力和做功能力大于等速向心收缩;3)左、右腿力量的平衡性因速度和支持方式的不同而表现不同趋势;4)支撑条件、动作速度和支撑方式对下肢各肌群肌电有非常显著性影响.     

我国优秀短距离速滑运动员直道滑冰腿部肌肉肌电特征研究

运用表面肌电和高速摄影同步技术,结合功能解剖学,分析短距离运动员直道滑冰单步周期腿部肌电特征。结果：（1）左腿振幅峰值前4的肌肉依次是股内肌、股外肌、胫骨前肌和腓肠肌,右腿振幅峰值前4的肌肉依次是股内肌、胫骨前肌、股外肌和腓肠肌,左、右腿振幅峰值最小的都是臀大肌;（2）单步周期腿部肌肉有效放电时间最长的都是胫骨前肌,最短的都是臀大肌;（3）单步周期腿部肌肉贡献度最大的肌肉依次是股内肌、胫骨前肌和股外肌。结论：（1）单步周期腿部肌肉振幅峰值都出现在蹬冰期,股四头肌和股后肌群在重心转移和蹬冰2个阶段都出现近似的振幅峰值,两者处于共激活状态,因此在训练实践中也要同步发展股后肌群力量;（2）单步周期中,股内肌、胫骨前肌和股外肌在腿部肌肉中有效放电时间最长、做功 最大,在完成单步周期动作时作用最大,臀大肌有效放电时间最短,做功最小,在完成单步周期动作时作用最小,但在训练实践中,胫骨前肌的作用被 低估,臀大肌的作用被高估;（3）运动员左、右腿单步周期动作模式一致,但摆动期左腿更主动,蹬冰期腿部肌肉的具体协调模式不同,在实践训练中设计练习方式时要注意左、右腿的差异。     

篮球弹跳练习15例

弹跳力是指通过下肢蹬地和全身协调用力,使人体迅速弹起腾空的能力。它是运动员的一项重要的身体素质,是各种运动项目的基础。一个人弹跳素质的好坏受多种因素的影响,如下肢和腰腹的肌肉力量,速度、灵敏和协调性;神经过程的灵活性,更主要的是练习方法。发展弹跳力的关键是在肌肉用力时做到爆发用力,使肢体,特别是下肢充分用力蹬地伸展后,又能做瞬间的充分放松、跳跃是由伸膝、髋、身干肌群和屈足肌群爆发性收缩完成的,它的用力性质属于速度力量,也称爆发力。在发展下肢力量时应以伸膝肌、伸踝肌(踝屈肌)为主,注意提高腿后肌群的力量和伸展性…     

优秀速滑选手于静实地滑冰和陆上模拟滑冰肌电特征比较研究

运用表面肌电遥测和高速摄影同步测试方法,结合功能解剖学知识,对于静实地滑冰和陆地模拟滑冰动作结构和肌电特征对比分析,探讨两者差异。结果显示:陆地模拟滑冰单步周期各动作阶段用时明显长于实地滑冰;实地滑冰和陆地模拟滑冰单步周期技术动作构成不一致;两者单步周期各阶段腿部肌肉放电强度存在差异,从单步周期总体来看,实地滑冰腿部各肌肉放电强度明显强于陆地模拟滑冰;实地滑冰腿部各肌肉最大用力程度均大于陆地模拟滑冰,主要用力肌肉股四头肌和股后肌群尤为明显。表明:陆上模拟滑冰作为陆上训练期保持滑跑感觉、体验滑跑技术细节和模拟滑冰全过程力量训练的方式不合理,长期坚持练习对改进滑冰技术动作细节有负面影响。     

普通高校速滑教学采用陆地模仿动作练习和实践的研究

普通高校速滑教学时数少,需采用有效方法提高教学质量。速滑教学采用陆地诱导和模仿动作的练习与轮滑模仿滑冰的练习,能有效地发展学生下肢肌肉力量和专项素质,有助于身体的平衡、协调能力的提高。陆地诱导和模仿练习的优点是条件简单,利于学生集中精力进行模仿练习,缺点是缺乏冰上动作的实感;冰上练习优点是具有冰上动作的实感,缺点是练习难度大,易分散学生的注意力。因此,采用轮滑模仿滑冰的练习,显示出速滑教学的优势。用轮滑模仿     

Carbohydrate ingestion improves endurance performance during a 1h simulated cycling time trial

This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue.     

Science and medicine of rowing: A review

The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae.     

我国体育市场管理法规研究

采用调查法和比较法对全国体育市场立法和管理现状进行调查,对部分较早出台并有一定代表性的省市的体育市场管理法规的立法和管理情况进行了研究,提出了体育市场管理立法和管理的原则、基本程序、措施及其一般模式,为规范全国体育市场管理提供参考依据。     

重新认识体育的社会关联

体育与政治之间存在一个悖论，体育的发展与经济实力之间没有直线相关，体育与教育部分重叠，体育与宗教最为近缘，体育可借用科学手段，体育的艺术禀性日益明显，体育与养生反映着两种人生观。     

上海社区体育竞赛参与者的特点探析

本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。     

对全面把握游泳训练环节的探讨

从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。     

我国优秀游泳运动员出发技术辅助训练的研究

为改进我国优秀游泳运动员的出发技术,采用观测和实验方法,通过拍摄运动员陆上和水下出发技术录像以及出发计时,对出发技术进行运动生物力学诊断和分析。在此基础上,根据运动员自身特点和不同泳姿提出相应的入水启动方式,并研制出发训练辅助器材,对出发预备姿势、腾起角度以及飞行远度和入水角进行控制。实践证明:这是一种快捷、有效的出发技术辅助训练方法。     

运动性呼吸肌疲劳与耐力性项目的运动能力

影响和限制耐力性运动项目的成绩的生理因素是复杂的和多方面的,取决于训练的强度和运动成绩.大强度持续性运动可导致呼吸肌疲劳.运动性呼吸疲劳可能在决定运动耐量方面起到关键的作用：一方面通过直接影响运动肌力量的生成（外周疲劳）,另一方面,通过肢体用力自感不安反馈引起工作肌运动单位输出功率下降（中枢疲劳）.对呼吸肌进行训练,可能有助于提高耐力性项目的运动成绩.     

青少年业余足球运动员运动倾向性5因素结构模型初探

根据Scanlan等人最新提出的运动倾向性理论模型,结合我国实际情况建立了青少年足球运动员运动倾向性5因素结构模型。运动倾向性被定义为:渴望和决心继续参加足球运动的心理状态。所建立的5因素结构模型认为,运动倾向性是由运动乐趣、参与选择、个人投入、社会约束及参与机会5个因素决定。经确定5个决定因素和运动倾向性的操作定义,编制了相应调查问卷,通过对北京市252名青少年足球运动员实测结果,建立运动倾向性及其影响因素的协方差结构模型,用Lisre 18分析的结果表明:该运动倾向性模型比较符合北京青少年足球运动员。其中运动乐趣、个人投入、参与机会和参与选择4因素对运动倾向性有影响;社会约束对运动倾向性影响不大。     

Effect of 6 weeks of endurance training on the lactate minimum speed

The aim of this study was to assess the sensitivity of the lactate minimum speed test to changes in endurance fitness resulting from a 6 week training intervention. Sixteen participants (mean +/- s :age 23 +/- 4 years;body mass 69.7 +/- 9.1 kg) completed 6 weeks of endurance training. Another eight participants (age 23 +/- 4 years; body mass 72.7 +/-12.5 kg) acted as non-training controls. Before and after the training intervention, all participants completed: (1) a standard multi-stage treadmill test for the assessment of VO 2max , running speed at the lactate threshold and running speed at a reference blood lactate concentration of 3 mmol.l -1 ; and (2) the lactate minimum speed test, which involved two supramaximal exercise bouts and an 8 min walking recovery period to increase blood lactate concentration before the completion of an incremental treadmill test. Additionally, a subgroup of eight participants from the training intervention completed a series of constant-speed runs for determination of running speed at the maximal lactate steady state. The test protocols were identical before and after the 6 week intervention. The control group showed no significant changes in VO 2max , running speed at the lactate threshold, running speed at a blood lactate concentration of 3 mmol.l -1 or the lactate minimum speed.In the training group, there was a significant increase in VO 2max (from 47.9 +/- 8.4 to 52.2 +/- 2.7 ml.kg -1 .min -1 ), running speed at the maximal lactate steady state (from 13.3 +/- 1.7 to 13.9 +/- 1.6 km.h -1 ), running speed at the lactate threshold (from 11.2 +/- 1.8 to 11.9 +/- 1.8 km.h -1 ) and running speed at a blood lactate concentration of 3 mmol.l -1 (from 12.5 +/- 2.2 to 13.2 +/- 2.1 km.h -1 ) (all P ? 0.05). Despite these clear improvements in aerobic fitness, there was no significant difference in lactate minimum speed after the training intervention (from 11.0 +/- 0.7 to 10.9 +/- 1.7 km.h -1 ). The results demonstrate that the lactate minimum speed,when assessed using the same exercise protocol before and after 6 weeks of aerobic exercise training, is not sensitive to changes in endurance capacity.