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1.
采用自主研发的摔跤滚桥测力系统结合定点摄像技术和表面肌电采集技术,对10名男子古典式摔跤一级运动员滚桥技术的动力学、运动学、表面肌电特征进行分析。结果显示:①滚桥技术的力量峰值出现在69°,运动员的滚桥技术峰值扭矩可达自身体质量的(2.11±0.64)倍。②右腹外斜肌和右臀大肌的肌肉激活持续时间最长,分别达5.83 s和5.94 s。③右股直肌、右腹外斜肌、右臀大肌分别在0~90°、0~120°、0~180°范围内做功水平显著高于对侧,左背阔肌在0~30°和120~180°范围内做功水平高于对侧。提示:①在滚桥技术初期,假人滚动的力量主要由双腿蹬伸迅速过渡到右腿侧向蹬伸用力、躯干右旋体位下左旋用力、左臂随躯干左旋方向提拉假人用力构成。②30°后,假人滚动的力量主要由右腿髋、膝关节伸展肌群和躯干左旋肌群收缩用力构成,在约69°时呈现滚桥技术峰值力量体位,此后滚桥力量持续减小。③120°后,假人滚动的力量主要由左肩伸展的拉动假人动作和右髋伸展的挺髋动作用力构成。  相似文献   

2.
目的:探讨青年男子排球运动员强攻扣球技术动作的关键;方法:使用两台高速摄像机和表面肌电仪对7名青年男子排球运动员强攻扣球手臂挥摆动作进行运动学和表面肌电学同步分析;结果:运动员在引臂后拉期主要由三角肌前束和三角肌后束完成,在甩臂击打期和击打作用期,肱三头肌、背阔肌、前臂屈腕的这些主动肌的电活动明显增强,起拮抗作用的肱二头肌和前臂伸腕肌群的电活动也非常强烈,而且,在各个阶段每对主动肌/拮抗肌表现为较好的协调性;背弓角为130.2°±4.7°、挥臂角为113.2°±6.1°、最后出手球速为23.5±0.7 m/s;背弓角,挥臂角与最后出手球速的相关系数r分别为-0.512(P<0.05)和0.484(P<0.05);结论:在强攻扣球手臂挥摆过程中,扣球臂的拮抗肌发挥着重要作用,起跳后挥臂的背弓角和挥臂角是影响最后出手球速的主要因素。  相似文献   

3.
目的：分析竞走运动员核心肌群的功能性特征,探讨核心肌群功能性特征对竞走技术的影响。方法：对我国6 名优秀20 km 竞走运动员主要核心肌群进行表面肌电测试和等动肌力测试。结果：（1）左右侧同名肌的MPF 和AEMG 存在显著性差异（P<0.05）。BF 和RF 协调性随运动速度的提高而下降;导致支撑腿着地时膝角减小5.5°、摆动时膝角增大15.4°。（2）核心肌群等动肌力不平衡。躯干左右侧旋转和屈伸相对峰力矩之比分别为8.7%和37%。髋膝关节屈伸肌力的总不平衡比为分别为34.3%±45.7%和18.8%±5.9%。肌力的不平衡导致支撑阶段两侧髋关节角位移差达到19.4°±9.9°,膝关为2.2°±1.6°。结论：核心肌群的上述特征将导致运动中身体稳定性的下降。建议运动员加强核心肌群的协调性与力量的平衡性训练。  相似文献   

4.
目的:旨在建立肌电与足底压力同步模型,从身体内部工作状态的角度探讨速度滑冰的一般规律。方法:同步测量速滑运动肌电与足底压力以及视频信号,建立速度滑冰直道蹬冰单周期模型,揭示运动员身体内、外参数的变化规律。结果:建立了速滑蹬冰单周期模型,提出膝角120°位置处的爆发力为速滑的主要用力特征,将速滑蹬冰单周期细分为6个阶段。结论:肌电与足底压力同步测量、同步肌电分析方法的结合能有效地获取速滑运动身体信息和揭示运动规律,是一种有力的体育科学研究方法。  相似文献   

5.
通过解剖学动作分析、表面肌电测试法,对古典式摔跤运动员使用提抱技术时的表面肌电进行实验测试,分析古典式摔跤运动员使用提抱技术的腰背肌肉协同变化过程.结果显示,在使用跪撑提抱技术时腰背肌肉中背阔肌做功百分比最高,平均为35%;主动肌的激活顺序为竖脊肌、背阔肌和肩胛提肌;在提抱技术中拮抗肌发挥着重要作用,且高水平运动员在提抱技术发力阶段,拮抗肌放电量与主动肌放电量有同步明显上升趋势.运动员应加强主动肌与拮抗肌的快速力量、反应力量和力量耐力训练,特别是针对性地进行专项力量训练.  相似文献   

6.
通过解剖学动作分析、表面肌电测试法,对古典式摔跤运动员使用提抱技术时的表面肌电进行实验测试,分析古典式摔跤运动员使用提抱技术的腰背肌肉协同变化过程。结果显示：1）在使用跪撑提抱技术时腰背肌肉中背阔肌做功百分比最高,平均为350k;2）主动肌的激活顺序为竖脊肌、背阔肌,肩胛提肌;3）在提抱技术中拮抗肌发挥着重要作用,且高水平运动员在提抱技术发力阶段;拮抗肌放电量与主动肌放电量有同步明显上升趋势;4）运动员应加强主动肌与拮抗肌的快速力量、反应力量和力量耐力训练,特别是针对性地进行专项力量训练。  相似文献   

7.
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   

8.
方法：利用CONTREX等速肌力测试与训练系统,以180°／s、120°／s、60°／s3种角速度对苏州市自行车训练队26名运动员右腿膝关节进行等速向心屈伸测试。目的：分析自行车运动员不同角速度下等速向心收缩与膝关节肌肌力的关系及肌力特征。结果：1、屈伸肌峰力矩随速度的增加呈减小趋势。2、到达峰力矩的时间随测试速度的增加而缩短。且男女运动员在180°／s与120°／s组间均无显著差异。3、膝关节相对平均功率伸肌均大于屈肌,120°／ts时,屈伸肌的相对平均功率最大。4、屈伸肌比在64．8％～70．6％内,有随速度增加而增加的趋势。结论：以60°／s的角速度训练肌肉最大力量效果更明显;爆发力在120°／s时训练效果最佳;屈／伸肌比值（H／Q）在正常范围内,但低于优秀运动员（优秀运动员可达80％以上）。  相似文献   

9.
等速向心运动中膝关节屈伸肌群的sEMG研究   总被引：1，自引：0，他引：1  
本文对女子柔道运动员等速向心运动过程膝关节屈伸肌群的表面肌电与运动速度以及峰力矩之间的关系进行了探讨,以期为进一步的研究以及力量测试、训练和评价提供参考。  相似文献   

10.
试验对象为2名国家健将级速滑运动员,用CYBEX NORM测髋、膝、踝三关节屈伸肌群的力矩.一组试验由8个角速度的试验组成.实验时,角速度间休息20s,组间休息半小时.每个人做3组试验.各人试验数据按关节角(间隔5°)、角速度组成样本后,做各关节角的不同速度的伸屈髋、膝、踝肌群的参数曲线族.试验发现:伸髋肌群在100°～145°之间时为较适宜发力区.而屈髋肌群在125°～165°之间为较适宜发力区.从最大力矩发生角度看,伸髋在115°～120°之间,屈髋在150°～155°之间.伸膝的适宜发力区在105°～145°之间,最大力矩值均发生在110°～120°之间.而屈膝适宜发力区在110°～155°之间,最大力矩值均发生在135°～145°之间.踝关节肌群无论是适宜发力区还是最大肌力的发生角度都随角速度的增加有所变化.  相似文献   

11.
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。  相似文献   

12.
ABSTRACT

A possible link between soccer-specific injuries, such as groin pain and the action of hip adductor muscles has been suggested. This study aimed to investigate neuromuscular activation of the adductor magnus (AM) and longus (AL) muscles during instep and side-foot soccer kicks. Eight university soccer players performed the two types of kick at 50%, 75% and 100% of the maximal ball speed. Surface electromyography (EMG) was recorded from the AM, AL, vastus lateralis (VL) and biceps femoris (BF) muscles of both kicking and supporting legs and the kicking motions were three-dimensionally captured. In the kicking leg, an increase in surface EMG with an increase in ball speed during instep kicking was noted in the AM muscle (p < 0.016), but not in AL, VL or BF muscles (p > 0.016). In the supporting leg, surface EMG of both AM and AL muscles was significantly increased with an increase in the ball speed before ball impact during both instep and side-foot kicks (p < 0.016). These results suggest that hip adductor muscles markedly contribute to either the kicking or supporting leg to emphasise the action of soccer kicks.  相似文献   

13.
The aim of this study was to describe and compare the EMG patterns of select lower limb muscles throughout the golf swing, performed with three different clubs, in non-elite middle-aged players. Fourteen golfers performed eight swings each using, in random order, a pitching wedge, 7-iron and 4-iron. Surface electromyography (EMG) was recorded bilaterally from lower limb muscles: tibialis anterior, peroneus longus, gastrocnemius medialis, gastrocnemius lateralis, biceps femoris, semitendinosus, gluteus maximus, vastus medialis, rectus femoris and vastus lateralis. Three-dimensional high-speed video analysis was used to determine the golf swing phases. Results showed that, in average handicap golfers, the highest muscle activation levels occurred during the Forward Swing Phase, with the right semitendinosus and the right biceps femoris muscles producing the highest mean activation levels relative to maximal electromyography (70–76% and 68–73% EMGMAX, respectively). Significant differences between the pitching wedge and the 4-iron club were found in the activation level of the left semitendinosus, right tibialis anterior, right peroneus longus, right vastus medialis, right rectus femuris and right gastrocnemius muscles. The lower limb muscles showed, in most cases and phases, higher mean values of activation on electromyography when golfers performed shots with a 4-iron club.  相似文献   

14.
包蕾  刘卉  高维纬 《中国体育科技》2020,(2):39-45,F0003
目的:描述艺术体操运动员在日常状况下和完成专项动作时脊柱异常的表现及左右对称性,探讨与之相关的因素。方法:以9名艺术体操运动员为研究对象,进行站立位脊柱X光片拍摄,获得脊柱额状面和矢状面的弯曲方向和角度;使用三维摄像方法定量评价运动员完成后搬腿动作和侧搬腿动作时的脊柱活动幅度;运用后伸肌群和双侧屈肌群测试系统对运动员的坐姿躯干后伸和双侧侧屈等长收缩力量进行测试。比较躯干活动幅度和躯干肌肉力量的左右对称性,比较不同脊柱侧凸方向间躯干活动差异。检验脊柱弯曲角度与躯干活动特征的相关性。结果:后搬左侧腿时的活动幅度显著小于后搬右侧腿(P<0.01),对应躯干向左扭转的幅度显著大于向右扭转幅度(P<0.05)。侧搬腿时躯干活动幅度越大对应的躯干扭转角度越大。胸曲角度与右侧搬腿活动幅度角存在正相关(P<0.05),与右侧搬腿躯干扭转角之间为显著负相关(P<0.05),腰曲角度与左侧搬腿活动幅度角之间存在显著正相关(P<0.05),与右侧搬腿躯干扭转角之间存在显著负相关(P<0.05)。肌肉力量方面,胸曲角度越大,3个位置躯干后伸力矩峰值越小。侧屈力量上,运动员绝大多数角度下的右屈力量显著大于左屈力量。胸曲角度、腰°曲角度分°别与不同躯干侧屈角度下右屈力矩峰值存在显著负相关。腰曲角度与左屈0、15°、30和右屈15°位置的躯干左屈力矩峰值存在显著负相关。结论:艺术体操运动员躯干两侧活动度和肌肉力量存在不对称,后伸幅度左侧大于右侧,侧屈肌力右侧大于左侧;但这种不对称与脊柱额状面上异常弯曲无明显关系;集中于躯干右侧和躯干后伸动作的训练,可能是导致胸曲变直的原因。  相似文献   

15.
ABSTRACT

Fractionated reaction time can be used to determine distinct epochs known as pre-motor, response and movement times (MTs) of a reaction time task. The purpose of this study was to compare elite and novice athletes performing a taekwondo kick in terms of the fractionated reaction time and electromyography (EMG) activation patterns of the muscles of the striking lower limb and the lower back. We hypothesised that the pre-motor time, response time (RT) and MT would be the shorter for elite athletes compared to novices. We collected data on 13 elite and 10 novice athletes when performing a roundhouse kick. The experiment included EMG electrodes placed on five low back and lower extremity muscles and an electrogoniometer placed on the kicking knee. We found that pre-motor time was shorter and the RT was longer for elite athletes than novice athletes. Moreover, the integrated EMG of the main knee extensor does not differ between groups though other leg and trunk muscles do. The results allow coaches and teachers to understand this particular taekwondo kicking movement which could ultimately improve the technique in order to establish training and teaching goals.  相似文献   

16.
Six competitive soccer players were recruited to examine EMG activation in three quadriceps muscles during a kicking accuracy task. Participants performed three maximum instep place kicks of a stationary ball, 11 m perpendicular from the centre of the goal line towards targets (0.75 m(2)) in the four corners of the goal. Surface EMG of the vastus lateralis, vastus medialis, and rectus femoris of the kicking leg was normalized and averaged across all participants to compare between muscles, targets, and the phase of the kick. Although no significant difference were observed between muscles or kick phases, kicks to the right targets produced significantly greater muscle activity than those towards the left targets (P < 0.01). In addition, kicks towards the top right target demonstrated significantly greater muscle activity than towards the top and bottom left (P < 0.01). Under accurate soccer shooting conditions, kicks aimed to the top right corner of the goal demonstrated a higher level of quadriceps muscle activation than those towards the other corners.  相似文献   

17.

Fast unloaded movements (i.e. striking, throwing and kicking) are typically performed in a proximo‐distal sequence, where initially high proximal segments accelerate while distal segments lag behind, after which proximal segments decelerate while distal segments accelerate. The aims of this study were to examine whether proximal segment deceleration is performed actively by antagonist muscles or is a passive consequence of distal segment movement, and whether distal segment acceleration is enhanced by proximal segment deceleration. Seventeen skilled taekwon‐do practitioners were filmed using a high‐speed camera while performing a high front kick. During kicking, EMG recordings were obtained from five major lower extremity muscles. Based on the kinematic data, inverse dynamics computations were performed yielding muscle moments and motion‐dependent moments. The results indicated that thigh deceleration was caused by motion‐dependent moments arising from lower leg motion and not by active deceleration. This was supported by the EMG recordings. Lower leg acceleration was caused partly by a knee extensor muscle moment and partly by a motion‐dependent moment arising from thigh angular velocity. Thus, lower leg acceleration was not enhanced by thigh deceleration. On the contrary, thigh deceleration, although not desirable, is unavoidable because of lower leg acceleration.  相似文献   

18.
采用ISOMED2000等速系统检测优秀散打运动员膝、肘关节肌群的生物力学特征,分析优秀散打运动员站位攻防动作技术.在进攻训练中伸膝关节速度达到300°/s,能充分发挥运动员小腿伸肌群的爆发能力;采用300°/s的速度可以快速屈小腿,有利于运动员快速回防,为再次打击对方在时间上创造了条件;在站位时,膝关节角度保持157.3°～160.1°,小腿屈肌群离心爆发能力强,有利于运动员调整自身的身体姿势,避开对方的快速进攻.在进攻训练中应使肘关节速度达到300°/s,能充分发挥运动员前臂伸肌群的爆发能力.肘关节角度在81°～86°的范围,有利于运动员快速出拳,打击对方.以240°/s的速度屈肘,能充分发挥运动员前臂屈肌群的爆发能力,有利于运动员快速回防.在防守训练中,肘关节角度在78°～85°的范围内,对运动员快速回防,抵御时方快速、重拳的进攻是有利的;肘关节角度在128°～137°的范围内,可远距离隔挡对方,阻击对方的快速进攻.  相似文献   

19.
PurposeThis study aimed to investigate whether there is a systematic change of leg muscle activity, as quantified by surface electromyography (EMG), throughout a standard running footwear assessment protocol at a predetermined running speed.MethodsThirty-one physically active adults (15 females and 16 males) completed 5 testing rounds consisting of overground running trials at a speed of 3.5 m/s. The level of muscle activity from 6 major leg muscles was recorded using surface EMG. The variables assessed were the EMG total intensity as a function of time and the cumulative EMG overall intensity. Systematic effects of the chronological testing round (independent variable) on the normalized EMG overall intensity (dependent variable) were examined using Friedman analysis of variates and post hoc pairwise Wilcoxon signed-rank tests (α = 0.05).ResultsThere was a systematic reduction in overall EMG intensity for all 6 muscles over the time course of the running protocol (p < 0.001) until the fourth testing round when EMG intensities reached a steady state. The one exception was the biceps femoris muscle, which showed a significant reduction of EMG intensity during the stance phase (p < 0.001) but not the swing phase (p = 0.16).ConclusionWhile running at a predetermined speed, the neuromuscular system undergoes an adaptation process characterized by a progressive reduction in the activity level of major leg muscles. This process may represent an optimization strategy of the neuromuscular system towards a more energetically efficient running style. Future running protocols should include a familiarization period of at least 7 min or 600 strides of running at the predetermined speed.  相似文献   

20.
The purpose of the study was to evaluate whether using only the semitendinosus as a tripled short graft would affect the electromechanical delay (EMD) of the knee flexors. EMD was evaluated in volunteers (N = 15) after they had undergone surgery for anterior cruciate ligament (ACL) reconstruction where the semitendinosus tendon alone was used as a graft. The results were compared with the intact leg and healthy controls (N = 15). After warming up, each subject performed four maximally explosive isometric contractions on an isokinetic dynamometer. Torques were measured by the dynamometer, while the electrical activity of the semitendinosus and biceps femoris muscles was detected using surface electromyography. EMD was found to be significantly increased (p = 0.001) in patients who had undergone ACL reconstruction compared to the controls. On the contrary, no significant differences (p = 0.235) were found for the biceps femoris muscle between the two groups. Similar results were found when the study group was compared with the intact leg group (p = 0.027 for semitendinosus and p = 0.859 for biceps femoris). Harvesting the semitendinosus tendon increases the EMD for the semitendinosus muscle but does not influence the EMD outcomes for the biceps femoris muscle.  相似文献   

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