如何提高立定跳远成绩

一、立定跳远的技术划分 立定跳远可分为准备姿势、蹬地、腾空和着地四个阶段,其中蹬地动作是关键。 （一）准备姿势 立定跳远的准备动作,是两臂预先上举和提踵,然后下蹲（髋膝关节屈,踝关节伸）,两臂用力后摆,身体总重心下降。 （二）蹬地 起跳时,当身体向前倾的一瞬间,两侧髋关节和膝关节迅速蹬伸,两臂前摆,最后通过有力的足迹屈踝关节蹬离地面。 （三）腾空 两前上摆,胸部向前上方挺,提腰,成展体挺身姿势。 （四）着地 准备落地时,两腿屈膝高抬,上体前倾,在脚触沙坑前,两腿尽量向前伸直,此时上体不应过分前倾。两臂由…     

立定跳远技术动作分析

一、立定跳远的技术动作描述两脚自然分开与肩同宽,站在起跳线后边,然后两臂自然前后预摆1~2次,两腿随着屈伸,当两臂从后向前上方做有力摆动时,两脚用前脚掌迅速蹬地,膝关节充分蹬直同时展髋向前跳起,身体尽量前送,在空间成直线,至最高点后屈膝、收腹、小腿前伸,两臂自上向下向后摆,落地时脚跟先着地,落地后屈膝缓冲,上体前倾。二、立定跳远动作完整的立定跳远技术动作由预摆、起跳、腾空、落地四个部分组成。     

立定跳远练习中的易犯错误及对策

立定跳远是发展腿部爆发力和全身协调能力的有效手段。正确的技术动作为:屈膝,双臂后摆;随着双腿蹬地,双臂用力向前上方摆出;腾空后积极收腹举腿;落地时双臂后摆,小腿前伸,尽可能向远处落地。完整的立定跳远技术过程如附图。     

立定跳远的“蹲”与“蹬”

在多年的教学实践中，笔者发现影响小学低年级学生立定跳远技术掌握与成绩的因素有两点：“蹲”与“蹬”。 　　一、蹲 　　“蹲”就是屈膝。在小学新生当中有很大一部分学生在练习立定跳远时的屈膝动作不好，表现为： 1起跳前的屈膝不够深； 2预摆中屈膝动作不协调，很缰硬； 3腾空时空中收腹屈腿动作不充分； 4落地屈膝缓冲不够。以上几种情形都很大程度上影响了动作的质量与效果。针对这种情况，经过反复摸索与实践，笔者归纳出以下有针对性的、相对能够较好掌握立定跳远动作、提高立定跳远成绩的教学方法： 　　1由半蹲开始的…     

立定跳远正确摆臂动作

立定跳远是发展腿部力量和爆发力,培养两腿快速蹬地起跳的练习,也是跳远落地的辅助动作。立定跳远时的正确摆臂动作至关重要。笔者在多年的教学实践中,发现有不少学生在立定跳远时有的臂基本不摆,起跳与摆臂的动作脱节,或是腾空时臂的摆动动作不对,或落地前的一瞬间...     

立定跳远的专门练习方法简

一、立定跳远的规范动作 全身放松,两脚开立与肩同宽,预备摆臂,身体半蹲,两臂上摆,脚尖蹬离地面,腾空展体,收腹,伸腿,落地,两臂积极前伸。     

立定跳远要加强起跳和腾空展体的练习

立定跳远是由预备、起跳、腾空和落地四个部分构成的,影响立定跳远成绩的主要因素主要有技术动作、学生个体身体素质、心理素质等方面的因素。立定跳远动作中的起跳和腾空展体阶段是相对较难掌握的阶段,教学中可以采用强化训练来改善和提高起跳和腾空的动作质量,最终提高学生的练习成绩。     

郑重提醒广大读者：旧投稿平台的稿件请尽决自行处理

笔者尝试以立定跳远为例进行具体分析教学重点与难点。一、从立定跳远技术本身剖析完整的立定跳远技术动作由预摆、起跳、腾空、落地四部分组成。1．预摆动作。教学重点是上下肢动作协调配合,教学难点是摆动时一伸二屈降重心的用力顺序。     

小学二年级教室内立定跳远辅助教学的实践探索

<正>本课设计了小学二年级立定跳远教学单元中的腾空技术动作教学。立定跳远包括预摆、起跳、腾空、落地4个环节,而腾空技术属于瞬间发生的连续性动作。水平一阶段的学生在学习立定跳远中,对腾空技术动作概念的认识比较模糊,不能较好地体会腾空时的收腹举腿动作。据此,笔者整合教室内场地和桌椅,在学生基本     

优秀青少年游泳运动员蹲踞式与抓台式游泳出发技术的对比分析

目的:基于青少年的生理特点,通过对比青少年游泳运动员采用蹲踞式和抓台式2种游泳出发技术时的运动学和动力学数据,以期为青少年游泳运动员的运动训练与比赛提供参考。方法:使用Kistler测力台和高速摄像机记录从青少年游泳运动员从准备姿势到入水的整个过程,通过对2种游泳出发技术参数的统计对比分析,总结这2种游泳出发技术的特点。结果:从游泳出发技术上来看,男性采用蹲踞式的加速蹬伸时间、地面反作用力峰值、腾空时间、腾空距离、平均水平腾空速度、出发总时间大于抓台式,而入水角度较小;女性采用蹲踞式的加速蹬伸时间、地面反作用力峰值、腾空距离、平均水平腾空速度大于抓台式,而腾空时间、入水角度、出发总时间较小。从性别角度看,男性采用蹲踞式的加速蹬伸时间、平均水平腾空速度、入水角度小于女性,而地面反作用力峰值、腾空时间、腾空距离、出发总时间较大;男性采用抓台式的加速蹬伸时间、平均水平腾空速度、入水角度小于女性,而地面反作用力峰值、腾空时间、腾空距离、出发总时间较大。结论:从游泳出发技术上来看,蹲踞式在滞台阶段加速蹬伸时间较长,但地面反作用力较大,且获得了更大的平均水平腾空速度,弥补了其滞台时间较长的缺点;在腾空阶段,在腾空时间无显著差异的情况下,蹲踞式具有明显较大的腾空距离,则蹲踞式在该阶段更具优势。从性别上来看,男性的加速蹬伸时间较小,且地面反作用力较大,但平均水平腾空速度较小,减小了男性在滞台阶段的优势;在腾空阶段,男性的腾空时间明显大于女性,但其腾空距离也较大。     

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.