共查询到19条相似文献，搜索用时 140 毫秒
1.
射箭运动技术诊断是该项目科学化训练的难点和要点,研究结果发现,通过超高速影像和三维红外线运动学分析的方法,以及高精度的时间、速度、位移等系列运动学指标的测量和射箭运动力学原理的综合运用,能够有效地监控射箭运动员的专项技术状态;高水平射箭运动员专项技术动作具有撒放时间短、声动反应快、箭速高、动作稳定性和一致性高的特点;另外,从功能原理与专项技术规律角度深入分析了反向动作与动作效率、动作稳定性等要素的因果关系,提出了优化撒放方式、减小反向动作幅度、增强动作控制能力是提高射箭技术水平的重要途径。 相似文献
2.
随着国内外射击运动成绩提高．比赛日趋紧张激烈。对运动员技术水平及自我控制能力提出了更高的需求。在技术水平接近的情况下．胜负往往决定于射手对外界干扰的自我调节能力与注意力集中动作过程的能力．射击运动对注意力集中能力的需求很高。 相似文献
3.
为探求优秀散打运动员的体重差异与鞭腿技术动作特征是否对击打速度产生影响。方法：运用VICON Nexus 3D运动捕捉系统,对小、中、大三个级别15名运动员运用鞭腿技术动作快速击打目标物时的运动轨迹进行采集。依据鞭打动作特点和下肢关节运动特征,将技术动作划分为四个时刻、三个时段,并对四个时刻下肢关节的角度以及三个时段的动作位移、时间、速度、角速度等运用VICON Polygon分析软件进行计算。结果表明：启动时段（P1）小级别运动员的躯干和支撑腿各关节运动幅度呈"上大下小"状态,大级别运动员呈"上小下大"状态;三个级别运动员作用腿下肢关节的运动方向相同,运动幅度却出现差异,小级别运动员启动时段的动作速度相对较快。击打时段（P2）三个级别运动员支撑腿的髋、踝关节回旋运动方向出现差异;作用腿下肢关节运动方向相同,中级别运动员膝关节屈曲角度相对较大、转动半径相对较小,击打时段的动作速度也相对较快。回收阶段（P3）三个级别运动员支撑腿髋关节屈伸、回旋运动方向出现差异;作用腿下肢关节运动方向相同,小级别运动员作用腿下肢关节转动半径相对较小,回收时段的动作速度也相对较快。不同级别运动员鞭腿技术动作特征对击打速度存在显著性差异,相同级别散打运动员减轻体重、改善下肢关节的运动方向和运动幅度,才是提高击打速度的重要途径。 相似文献
4.
竞走作为一项流行运动与人类其他行走方式有着根本的区别。本研究的目的是描述竞走过程中的动力学和运动学指标与正常走各指标的差异,探讨受限于竞走规则的动作是否会造成对竞走运动员的潜在伤害。研究选取14名优秀竞走运动员作为测试对象,使用Rs-SCaB测力板和3台SONY摄像机采集竞走和正常走的动力学和运动学指标,采用配对T检验的统计学方法来比较两种行走方式的指标差异。在竞走中,足跟外侧（H1）和足跟内侧（Hm）压力峰值、地面反作用力第一、第二压力峰值和谷值大小、压力中心曲线在前后方向和左右方向的位移等指标都显著大于正常走。支撑腿着地时伸直的膝关节引起了足跟外侧（H1）和足跟内侧（Hm）压强峰值的增大;竞走中较大的水平速度、较大的水平冲力和较快的踝关节背伸速度分别造成了地面反作用力第一、第二峰值和谷值的增大;更多的大脚趾肌肉用力和较大的髋关节内收动作造成了竞走时足底压力中心曲线在前后方向和内外方向的位移增大。竞走时较大的足跟部位压力峰值和较大的踝关节外翻角度以及大脚趾肌群的过度利用可能是由竞走规则导致的潜在伤病因素。 相似文献
5.
许翀 《武汉体育学院学报》2017,51(10):93-100
短跑起跑阶段需要对外部信号集中注意并快速反应，以产生最佳运动表现。因此，本研究假设：狭窄外部注意焦点导向会对短跑选手的起跑表现产生有益影响。研究基于短跑起跑的三个动力学阶段（实际反应时阶段，蹬起跑器反应动作时阶段和加速跑阶段），测试新手和精英短跑选手在一段10M的短跑起跑中，在3种注意焦点导向条件下（狭窄外部注意导向、狭窄内部注意导向、中性指导语）的起跑表现。研究结果显示：在狭窄外部注意导向条件中，实际反应时、反应动作时和起跑加速时均显著短于狭窄内部注意焦点导向条件中的时间。研究结果证实：（1）根据信号而启动的短距离快速移动项目中，狭窄外部注意焦点导向会产生有益影响。（2）不同的注意焦点导向会影响动作表现。 相似文献
6.
通过对自行车运动员和普通健康者的血液流变的测试及分析得出：（１）自行车运动员的最大吸氧量与运动后血细胞压积呈负相关；（２）自行车运动员和普通受试者运动后血乳酸同运动前后的某些血液流变性指标呈正相关。表明：血液流变性与最大有氧能力、运动后乳酸之间有一定关系。 相似文献
7.
8.
目的：探求8周舒尔特方格练习法对射箭运动员注意力及成绩的影响,以期为射箭运动员的注意力训练提供参考。研究方法：选取山西大学射箭队队员28名,随机分为实验组(8周传统训练并接受舒尔特方格练习)及对照组(8周传统训练)各14名;经8周训练后,比较两组注意力量表统计结果和传统弓排位赛成绩变化情况。研究结果：(1)在8周训练后,实验组运动员注意力集中能力、转移能力均得到显著提高(P<0.05),对照组运动员注意力指标和实验前无显著性差异。(2)实验组与对照组比赛成绩均明显提高,且实验组射箭运动员比赛成绩的提升幅度显著高于对照组(P<0.05)。结论：舒尔特方格练习法能够有效提高射箭运动员注意力,从而提高射箭运动员的项目成绩,相比于传统训练方法,提高效果更加明显。 相似文献
9.
目的：探讨优秀女子举重运动员抓举动作的动力学特点。方法：采用比利时产Footscan足底压力测试系统对四名优秀女子举重运动员的四次成功抓举动作进行分析。结果：（1）四人在抓举整个过程中,身体压力中心的左右波动幅度均大于前后波动幅度。其中发力阶段左右和前后波动最大,而下蹲支撑阶段和提铃阶段波动较小;（2）与其他阶段相比,下蹲支撑阶段的压力中心运动轨迹最小;（3）在抓举整个过程中,身体稳定性顺序为下蹲支撑阶段〉提铃阶段〉上举阶段〉发力阶段,阶段总压力差表现为发力阶段〉下蹲支撑阶段〉上举阶段〉提铃阶段。结论：四人在抓举过程中符合＂近、快、低＂、和下蹲＂低、稳＂的要求。付小娟需加强提铃和上举阶段身体的稳定性,郭晴和张茜需加强发力阶段的稳定性。 相似文献
10.
目的:检测太极拳蹬腿动作支撑腿和动作腿的协调活动,揭示中枢双重命令下的下肢运动控制的特征.方法:太极拳运动员和初学者各10人,分两组.记录太极蹬腿动作时下肢肌肌电图、双下肢关节的角运动、足底中心压力的移位.每次试验8 s完成,重复5次.统计处理后,做肌电、运动和平衡分析.鲒果:两组间支撑腿的EMG、关节活动和COP位移出现了在形态上和幅度上的差别,但是在动作腿多表现在幅度上的差别.运动员支撑腿的平均EMG都高于初学者,只有股直肌有显著差异;运动员膝和髋关节的平均最大运动角度小于初学者,踝关节的平均最大运动角度稍稍比初学者大,只有髋关节的平均最大运动角度较为显著.运动员动作腿的平均EMG只有股直肌和胫骨前肌显著地高于初学者,而臀中肌显著地低于初学者;所有关节的平均最大运动角度都是运动员的显著大于初学者.平均足底中心压力的侧方和前后方位移都是运动员的显著大于初学者.运动员动作腿的起始运动约250～350ms,滞后于支撑腿起始运动的延迟时间.结论:运动员和初学者都可以用踝-髋策略来调节单腿直立的姿势平衡,但是运动员能够启动一个根据任务需要的前馈控制技术,通过下肢肌的积极活动,预先形成一个对抗蹬腿反作用力干扰的姿势稳定.因此,训练太极拳可以获得这个前馈控制技术.持续降低重心时,初学者的蹬腿和支撑两任务间出现了相互冲突. 相似文献
11.
The study investigated the coordination and variability of posture and pistol motion for skilled pistol shooters and novices in a pistol-aiming task. The participants stood on a force platform and held a pistol with the preferred arm to aim for accuracy to a target on 30 s trials. The results revealed that the amount of the centre of pressure (COP) and pistol motion was lower for the expert than novice group. The time–varying structure of COP as indexed by multiscale entropy (MSE) and detrended fluctuation analysis (DFA) was also lower for the expert than the novice group. The relative phase between the COP in the anterior–posterior (AP) and pistol in the AP and between the COP in the medial–lateral (ML) and pistol in AP was close to inphase for the both groups. However, for the novice group the coordination patterns of posture and pistol motion were more variable with the pistol motion leading the posture motion while it was lagging in the skilled group. The findings show different qualitative and quantitative dynamics in pistol-aiming as a function of skill level with postural control foundational to supporting the reduced dispersion and complexity of the skilled arm-pistol motion. 相似文献
12.
Adam C. Knight Megan E. Holmes Harish Chander Amari Kimble Joshua Ty Stewart 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(2):169-179
Track and field events place different demands on athletes and may have an effect on balance. This study investigated the effects of event specialty, gender, and leg dominance on balance among adolescent track and field athletes. Forty healthy adolescent track and field athletes (male = 23, female = 17) categorised into three different groups (sprinter = 20, distance runners = 13, throwers = 7) had their single leg static balance measured with the eyes open and the eyes closed using an AMTI force platform. Dependent variables included average displacement (cm) of the centre of pressure (COP) in the anterior/posterior direction and medial/lateral directions, the average velocity of the COP (cm/s) and the 95% ellipse area (cm2). Variables were analysed using a 3 (event specialty) × 2 (gender) × 2 (leg) ANOVA with repeated measures on the leg variable (p < 0.05). There was a significant difference (p < 0.05) in the average displacement of the COP in the medial/lateral direction for both the eyes open and closed condition, with the non-dominant leg demonstrating greater displacement than the dominant leg. This might increase the risk of injury for the non-dominant leg, but additional data should be collected and analysed on both dynamic balance and performance. 相似文献
13.
目的通过观察不同运动等级散打运动员在使用鞭腿技术动作时,支撑腿踝关节运动学特征所出现的差异,探求运动学特征与外侧副韧带急性损伤风险的关系。方法运用VICON Nexus 3D红外运动捕捉系统和Kistler地面测力系统,对23名不同运动等级男子散打运动员在使用鞭腿技术时支撑腿踝关节的动作轨迹进行采集,依据运动链原理将运动轨迹划分为启动、击打、回收3个时段,利用VICON Polygon分析软件对每个时段踝关节的角度、角速度、位移、时间、速度等特征进行分析。结果在击打过程中,不同运动等级运动员踝关节的运动方向一致,踝关节的活动度却出现了差异,启动和回收时段的内翻角度存在显著性(P<0.05);一般运动员踝关节的动作时间、位移均大于优秀运动员,启动时段的动作时间、上下位移、动作速度存在显著性(P<0.05)。结论不同运动等级散打运动员支撑腿踝关节的运动学特征存在显著性差异,优秀运动员踝关节运动轨迹的稳定性整体上好于一般运动员;运动学特征与引发外侧副韧带急性损伤风险存有关联,一般运动员因踝关节活动度相对较大,引发外侧副韧带急性损伤的风险也相对较高;启动时段是引发踝关节外侧副韧带急性损伤风险的最大时段。 相似文献
14.
目的:探讨不同踝关节稳定程度对侧跳落地缓冲时姿势稳定策略与神经肌肉控制的影响。方法:36名男性大学高水平运动员为受试者,按照踝关节不稳定程度分为12人健康组(CON)、12人隐患组(LAT)和12人不稳定组(CAI),以随机顺序执行4次单足连续侧跳动作,涉及外侧侧向跳动作(SHL)与内侧侧向跳动作(SHM)。使用VICON三维动作捕捉系统、KISTLER测力板与DELSYS无线表面肌电收集下肢生物力学参数;使用独立样本单因子方差分析(one-way ANOVA)比较各组在起跳后落地5个阶段的下肢关节运动学参数、动力学参数及肌肉激活水平。结果:1)下肢矢状面肌群激活程度与踝关节肌肉共同收缩率,对CAI组的动态姿势稳定扮演重要角色,以SHL落地的踝关节外翻动作能降低踝关节内翻扭伤风险;2)在SHL落地模式下,CAI组髋关节内收动作可能会引起踝关节内翻动作,侧跳落地的踝关节内翻角速度出现较早且快速的特征是CAI组反复扭伤的关键;3)踝关节策略主要影响压力中心(COP)参数,髋关节策略则能改变质量中心(COM);CON组侧跳的落地缓冲与姿势控制能力不及CAI稳定;SHM落地模式是踝关节内翻扭伤的高风险动作。结论:CAI组运动员即便在扭伤康复后,仍存在再次扭伤的可能,可针对踝关节活动范围与神经肌肉控制进行强化与训练,避免反复损伤。 相似文献
15.
运用三维运动学分析方法,对参加国际田联竞走挑战赛女子20km比赛前8名运动员后半程中一个复步进行解析。结果表明,我国运动员在后半程中,运用的是步长较短,步频较快的技术风格;腾空时间总体上处于犯规时限的下限,膝关节从着地瞬间直至垂直支撑面保持了可见的伸直状态,但在最后冲刺阶段,膝角出现了模糊伸直过程;身体重心垂直位移、头顶位置上下起伏均高于世界优秀运动员平均水平,这既与踝关节后蹬伸展离地时机偏早、用力动作不充分有关,也与着地瞬间摆动腿前摆后的前伸着地动作不够积极有关。在注意后蹬动作的同时,还应强化摆动腿积极的前摆着地动作。躯干倾角基本处于正常范围之内,但左、右腿蹬伸用力不均衡造成身体重心左、右偏差较大的情况容易导致动作外观不稳定而被判罚技术犯规。我国运动员肩髋扭转角度较小是导致步长相对较短的一个重要成因。 相似文献
16.
Yasuharu Nagano Hirofumi Ida Masami Akai Toru Fukubayashi 《Journal of sports sciences》2013,31(14):1525-1534
Abstract Female athletes are considered to exhibit knee and trunk motion that is characteristic of anterior cruciate ligament (ACL) injury. The aim of this study was to examine the in vivo motion of the trunk and knee during a cutting manoeuvre and determine the relationship between them. All participants (10 male and 10 female college athletes) performed a shuttle run cutting task with the left limb. Trunk inclination (forward and lateral) and knee joint angles (flexion/extension, abduction/adduction, and internal/external tibial rotation) were calculated. Differences between the sexes and associations between knee motion and trunk inclination were examined. An increase in trunk forward inclination was strongly correlated with an increase in knee flexion angle and moderately correlated with a decrease in the excursion of internal tibial rotation. An increase in right trunk lateral inclination was moderately correlated with an increase in excursion of internal tibial rotation. The results also showed differences between the sexes in trunk forward inclination, lateral inclination, and knee flexion angle, but no such differences in knee abduction or internal tibial rotation. Trunk inclination is related to knee flexion and excursion of internal tibial rotation. Female athletes demonstrate a low trunk forward inclination and knee flexion angle, a posture that resembles that of ACL injury. 相似文献
17.
Timothy A. Exell Marianne J.R. Gittoes Gareth Irwin David G. Kerwin 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):532-541
The aims of this study were to evaluate the accuracy of centre of pressure (COP) data obtained during transition of load across the boundary between two force plates, and secondly to examine the effect of such COP data on joint kinetics during sprint running performances. COP data were collected from two piezoelectric force plates as a trolley wheel was rolled across the boundary between the plates. Position data for the trolley were collected using an opto-electronic motion analysis system for comparison with COP data. Mean COP errors during transition across the plate boundary were 0.003 ± 0.002 m relative to a control point. Kinematic and kinetic data were also collected from eight athletes during sprint running trials to demonstrate the sensitivity of the inverse dynamics analysis to COP error for the ground contact phase of the dynamic movement trials. Kinetic sensitivity to the COP error was assessed during the entire stance phase for the ankle, knee, and hip joints and was less than 5% and 3% for joint moment and power data, respectively. Based on the small COP error during transition across plate boundaries, it is recommended that foot contacts overlapping two force plates may be included in inverse dynamics analyses. 相似文献
18.
When developing motor skills there are several outcomes available to an athlete depending on their skill status and needs. Whereas the skill acquisition and performance literature is abundant, an under-researched outcome relates to the refinement of already acquired and well-established skills. Contrary to current recommendations for athletes to employ an external focus of attention and a representative practice design, Carson and Collins' (2011) [Refining and regaining skills in fixation/diversification stage performers: The Five-A Model. International Review of Sport and Exercise Psychology, 4, 146–167. doi:10.1080/1750984x.2011.613682] Five-A Model requires an initial narrowed internal focus on the technical aspect needing refinement: the implication being that environments which limit external sources of information would be beneficial to achieving this task. Therefore, the purpose of this paper was to (1) provide a literature-based explanation for why techniques counter to current recommendations may be (temporarily) appropriate within the skill refinement process and (2) provide empirical evidence for such efficacy. Kinematic data and self-perception reports are provided from high-level golfers attempting to consciously initiate technical refinements while executing shots onto a driving range and into a close proximity net (i.e. with limited knowledge of results). It was hypothesised that greater control over intended refinements would occur when environmental stimuli were reduced in the most unrepresentative practice condition (i.e. hitting into a net). Results confirmed this, as evidenced by reduced intra-individual movement variability for all participants’ individual refinements, despite little or no difference in mental effort reported. This research offers coaches guidance when working with performers who may find conscious recall difficult during the skill refinement process. 相似文献
19.
Female athletes are considered to exhibit knee and trunk motion that is characteristic of anterior cruciate ligament (ACL) injury. The aim of this study was to examine the in vivo motion of the trunk and knee during a cutting manoeuvre and determine the relationship between them. All participants (10 male and 10 female college athletes) performed a shuttle run cutting task with the left limb. Trunk inclination (forward and lateral) and knee joint angles (flexion/extension, abduction/adduction, and internal/external tibial rotation) were calculated. Differences between the sexes and associations between knee motion and trunk inclination were examined. An increase in trunk forward inclination was strongly correlated with an increase in knee flexion angle and moderately correlated with a decrease in the excursion of internal tibial rotation. An increase in right trunk lateral inclination was moderately correlated with an increase in excursion of internal tibial rotation. The results also showed differences between the sexes in trunk forward inclination, lateral inclination, and knee flexion angle, but no such differences in knee abduction or internal tibial rotation. Trunk inclination is related to knee flexion and excursion of internal tibial rotation. Female athletes demonstrate a low trunk forward inclination and knee flexion angle, a posture that resembles that of ACL injury. 相似文献