网球初学者易犯错误及纠正方法

网球运动是—项技术性很强，动作要求很高的运动。初学者由于缺乏专业人士的指导常出现—些错误动作，如何在打球过程中找出自己技术动作的毛病，并通过有效的练习方法进行改正，这是网球爱好者的热门话题。本文就网球初学者常出现的一些错误动作进行分析，并介绍一些纠正错误动作的练习方法，供网球爱好者参考。     

形象思维在体操动作教学中运用

传统的体操动作教学，一般都是采用示范讲解、组织练习、观察指导、纠正错误的形式进行。通过示范使学生在头脑中形成动作表象，通过讲解使学生建立起动作概念，通过组织练习、指导、纠正错误使学生体会动作方法进而完成动作。在学生的头脑中形成动作表象和建立动作概念是学生学习动作技术的先决条件，在此基础上的反复练习则是学生掌握动作技术的必要过程。如何使学生尽快地形成动作表象，建立正确的动作概念，在练习中以合理的动作技术去完成符合规格要求的动作，一直是体操动作教学中的核心问题。在多年的教学实践中我们体会到，在示范、…     

浅谈蛙泳的“翻脚”

初学蛙泳，脚部动作的掌握是重点，而腿部动作中的翻脚技术是关键。我们在多年的蛙泳初学班的教学实践中，针对翻脚技术，采取了以下的教学方法。 一、讲解、示范中重点强调翻脚技术，以引起学员的重视。 二、陆上练习中重点练习，熟练后再进行水中练习。 三、经过一段时间的水中持“手板”腿部动作的练习，一部分水感好的学员，腿部动作基本正确，掌握了翻脚技术，这时，要把掌握翻脚技术的学员和未掌握翻脚技术的学员分开进行练习。掌握翻脚技术的学员，在这个阶段要多进行水中持“手板”腿部动作的练习，教练员则在水中重点提示或“扳”…     

支撑跳跃教学方法改革新尝试

在支撑跳跃教学中，我们改革传统的教学方法，以全新教法进行尝试，取得较好效果。在教学中去掉踏板，降低跳马高度，教师提出几个简单的过马动作方法，自己不做示范指导学生去尝试。例如：跳上成跪撑跳下、跳上成蹲撑跳下、双手支撑侧跨过等，对于这些动作没有规定性要求，学生可以任意完成。在简单练习的基础上，教师可以引导学生用自己的语言共同探究一些新的过马动作方法进行练习。在练习时，教师要根据学生身体素质的差异性，因人而异地引导学生进行与之相适合的动作练习。同时为了提高学生练习的兴趣，调动学生练习的积极性，教师也可…     

巧用墙壁提高体育教学有效性

一、利用墙壁的反弹功能 在各种球类基础动作练习中,利用墙壁使球反弹回来,能有效提高练习密度和动作反应速度,通过不断地强化训练,缩短技术动作定型时间,有效提高课堂教学效率. 1.单人练习 强调练习的稳定性.通过自己反复对墙练习,逐步体会击球点、落点、手指、手腕、手臂动作不同感觉,不断积累经验达到技术动作自动化.如乒乓球对墙打,排球传、垫、扣、发球练习,篮球传接球练习(单球、双球),羽毛球对墙打、网球、壁球练习等等.在练习过程中,注意技术动作练习的准确性,避免出现错误的动作习得. 2.双人、多人反练习 强调练习的随机性.通过多人参与同一练习,使练习环境不稳定(二人接打一只乒乓球).通过设置不同目标的比赛,来提高练习者接、打球的难度,激发运动兴趣.接近实战,有效的促进学生运动技能的掌握.     

体育教学中内心演练教法的初步研究

内心演练教学法要求学生在开始练习之前，停止运动技术动作练习，在头脑里反复重现已学过的技术动作的形象，在脑中形象化、动作结构完整化和系统化，从而使技能达到熟练程度，形成技巧。     

侧踹腿技术的教学与应用

侧踹是散打练习中的主要技术动作之一，教学中必须抓住要点，对学生进行相关教学，才能达到预期的教学效果。一、正确示范正确的示范不仅可使学生通过直观的感性认识来获得正确的动作概貌，并能通过对比分析自身动作的不足，取长补短，不断完善侧踹腿的动作技术。二、加强辅助性动作的练习1.劈叉、横叉、竖叉。通过练习提高身体的柔韧性。2. 踢腿、外摆、里合。行进间进行左腿外摆、右腿里合加转体练习，结合跳起里合拍击掌练习。着重提高摆腿速度，增加髋关节灵活性。三、侧踹腿技术的分类1. 进攻性侧踹腿在散打练习中。双方都处于严密的…     

原地高抬腿跑易出现的错误动作及纠正方法

原地高抬腿跑是中小学体育课中常用的练习，它简单、易行、有效，常出现在体育课的准备活动部分和基本部分跑的辅助练习和专项训练内容中，学好、用好这一技术动作，对学生学习、改进途中跑的技术动作，提高跑的速度都有很大的帮助。如果动作不对、练习不当就会事倍功半，甚至破坏跑的技术动     

男子跳马前手翻直体前空翻转体900°动作的运动学分析

运用文献资料法、观察法和运动学研究方法，对男子跳马前手翻直体前空翻转体900°动作进行运动学分析，找出该动作的技术特征和技术要领，提出素质练习、在弹网上练习、小弹网或三到五岁上板做扶马的练习、负重练习、完善关键性技术的练习、弹网上进行前屈两周转体900°动作的练习等辅助练习手段。     

动作示错在体育教学中的运用

动作示错是对错误技术动作进行模仿示范。在体育技术教学过程中，如何预防和纠正学生在练习中的错误动作，加快对正确技术动作的学习和掌握，是体育教学工作者应认真研究的课题之一。在长期的教学实践中，笔者采用动作示错这种直观教学方法，预防和纠正学生在练习中出现的各种错误动作，促使正确技能的动作形成，收到了良好的教学效果。     

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.