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运动性肌肉疲劳过程中主动肌与拮抗肌sEMG相干性分析 总被引：3，自引：1，他引：2
目的:通过静态疲劳负荷实验过程中主动肌与拮抗肌sEMG的相干性分析探索运动性肌肉疲劳过程中中枢神经系统对主动肌与拮抗肌共神经输入(common neural inputs)同步支配的变化特征。方法:以10名健康男性青年志愿者为研究对象,记录受试者以50%MVC负荷强度静态屈肘运动诱发肌肉疲劳过程中主动肌肱二头肌与拮抗肌肱三头肌的sEMG,为考查疲劳因素对相干性分析结果的影响作用,对记录的sEMG按运动持续时间平均分为两段,分别对两段sEMG进行相干性分析处理。结果:在疲劳负荷实验过程中,肱二头肌与肱三头肌MF指标随运动持续时间表现出显著性的单调递减变化趋势。从相干性分析结果看,在beta频段和gamma频段内,运动后半段肱二头肌与肱三头肌sEMG相干函数值要明显小于运动前半段,而tremor频段内无显著性差异。结论:在50%MVC静态负荷屈肘运动致肌肉疲劳过程中,随着负荷运动持续时间的增加,中枢神经系统对主动肌肱二头肌与拮抗肌肱三头肌共神经输入同步支配下降,这可能是由于主动肌与拮抗肌脊髓运动神经元兴奋性及运动皮层对脊髓运动神经元激活能力随疲劳发展的下降不同步性及为维持既定的收缩负荷,中枢神经系统对主动肌与拮抗肌运动单位的募集策略采取不同的调节方式造成的。 相似文献
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目的：探讨不同水上运动项目优秀男子运动员安静状态下肱二头肌微循环相关指标与运动项目、运动员等级及专项训练年限的关系方法：利用PeriFlux Syste m 5000系列激光多普勒仪自带的血流单元、温控单元及经皮氧分压单元,对47名不同水上运动项目抛秀男子运动员进行安静、坐位状态下肱二头肌微循环相关指标进行测试,测试环境为室内,室温250±3．0℃、空气相对湿度45．0％～65．0％,结果：不同水上运动项目优秀男子运动员肱二共肌微循环血流灌注量（PU）、血细胞的运动速率（V）、经皮氧分压（tcpO2）皮艇组〉赛艇组〉帆船组,加热后PU变化率帆船组〉赛艇组〉皮艇组,加热后微循环相关指标变化率帆船组〉皮艇组;不同运动等级水上运动项目优秀男子运动员安静时肱二头肌PU、V一级运动员组〉二级运动员组〉健将级运动员组,而加热后PU的变化率、运动的血细胞聚集程度（CMBC）的变化率健将级运动员组〉一级运动员组〉二级运动员组;不同专项训练年限水上运动项目优秀男子运动员安静时肱二头肌微循环PU、V1-5年组〉6～9年组〉10年以上组,结论不同水上运动项目优秀男子运动员安静状态下肱二头肌部分微循环相关指标与运动项目、运动员等级及运动员专项训练年限有关。 相似文献
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不同负荷强度运动时表面肌电图中位频率与血乳酸浓度变化的关系 总被引：8，自引：1，他引：7
采用等速运动方式 ,以表面肌电图和血乳酸为指标 ,在 10 %、3 0 %和 50 %MVC三种负荷条件下 ,对肘关节屈伸运动时的肱三头肌、肱二头肌和前腕骨肌的表面肌电图和血乳酸浓度的变化进行了比较分析。结果表明 :(1)肘关节屈伸运动时 ,伸展运动的力矩峰值下降幅度大于屈曲运动。 (2 )以 3 0 %和 50 %MVC负荷强度运动时 ,出现了表面肌电图的MF值逐步下降和血乳酸浓度逐渐增加的现象 ;工作肌群MF下降幅度 ,由大到小依次为肱三头肌 >肱二头肌 >前腕骨肌。 (3 )肱三头肌、肱二头肌和前腕骨肌的表面肌电图的MF变化与血乳酸浓度变化相互比较 ,10 %、3 0 %和 50 %MVC三种运动形式都表现出了非常明显的相关性。实验结果可以说明 ,sEMG作为特异性良好的非损伤性检测手段 ,不但能够直观地反映肌肉的收缩活动 ,还与肌肉组织代谢变化有一定的相关关系 相似文献
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通过文献调研和专家访谈,对青少年运动员肱二头肌力量训练方法进行了整合与分析,重点引入了力量训练“危险收效比”的理论与方法,有针对性的研究了肱二头肌力量训练的风险收益问题,以期为青少年肱二头肌力量训练的科学化提供必要参考。 相似文献
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单侧肢体运动对对侧肌肉肌电频率的影响 总被引：3，自引：1，他引：2
目的:研究单侧肢体动态运动诱发肌肉疲劳对对侧肌肉肌电信号平均功率频率(MPF)的影响,验证MPF下降的中枢控制作用.方法:10名男性受试者一侧上肢(负荷臂)分别完成5kg持重动态运动负荷实验和无负重放松实验,记录另外一侧(观察臂)完成4kg持重等长运动实验时肱二头肌、肱三头肌和斜方肌的sEMG信号,考察负荷臂两种运动状态下观察臂肌肉肌电的MPF、平均肌电值、复杂度和有序性等变化的差异性.结果:5kg持重动态运动实验过程中观察臂肱二头肌、肱三头肌和斜方肌的MPF均值均显著低于无负重放松实验状态;肱三头肌MPF的下降斜率显著增加.结论:负荷臂动态运动诱发一侧肌肉疲劳过程中可以造成对侧观察臂肌肉平均功率频率产生伴随性变化,表明sEMG信号活动具有确切的中枢控制成分. 相似文献
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针对运动员肱二头肌长头腱陈旧性损伤原因、机理、症状进行分析、诊断 ,采用按摩加上肢运动方法进行治疗 ,效果明显 ,供同行参考 相似文献
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肱二头肌长头腱腱鞘炎及脱位一、肱二头肌长头腱腱鞘炎(一)病因及发病机制病因主要为外伤和变性。投掷运动、棒球和网球运动后常急性发病,多因未做好准备活动而引起。某些工作需肩部反复活动,导致肌腱慢性损伤,发生创伤性炎症。40岁以上的中年人,长期磨损而致退行性变者更易发生。腱鞘充血、水肿、纤维化、增厚,鞘管内粘连,肌腱滑动障碍,甚至不能滑动,产生临床症状。 相似文献
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牵拉方法治疗慢性肱二头肌长头肌腱腱鞘炎山东省体育运动技术学院陈金常，陈薇目前对慢性肱二头肌长头肌腱腱鞘炎的治疗，多采用局部封闭，即以２％奴夫卡因２～３毫升加ＨｙｄｒｏｔｉｓｏｎｅＡｃｅｔａｔｅ１２～１３毫克的混合液局部封闭，或用奴夫卡因加其它针剂注入... 相似文献
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目的：对陈式太极拳的典型发劲动作掩手肱捶进行测试,采集不同水平练习者掩手肱捶劲力发放的运动学、动力学和肌电结果,分析和讨论掩手肱捶劲力发放的特点和训练方法。方法：研究对象共14人,试验组和对照组各7人。试验仪器包括VICON三维运动分析系统,Noraxon16导遥测肌电DTS系统,中国功夫测试工程人。测试动作为陈式太极拳的典型发劲动作掩手肱捶。试验组和对照组的测试结果比较采用配对样本T检验,试验组空击动作与实击动作的结果比较采用独立样本T检验。结果：陈式太极拳试验组在右手位移、右手速度、加速度、最大加速度的结果上高于对照组,虽然试验组的平均肌电明显小于对照组,但试验组的肱桡肌、肱二头肌、肱三头肌、三角肌、背阔肌、竖脊肌峰值肌电值大于对照组,其中肱二头肌和背阔肌的差异有统计学意义;在击打效果上,试验组击打在工程人心脏、左肺、右肺和胃的加速度值明显高于对照组。结论：试验组的峰值肌电高于对照组,主要是肱桡肌、肱二头肌、肱三头肌、三角肌、背阔肌、竖脊肌在完成掩手肱捶时用力明显,建议在完成该动作时应进行针对性地练习;掩手肱捶击打到工程人时的加速度呈双峰波型,第1个波形高,而第2个波形低,这与该动作在动作结束时有旋腕动作有关。 相似文献
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Ayako Higashihara Yasuharu Nagano Kazumasa Takahashi Toru Fukubayashi 《Journal of sports sciences》2015,33(13):1366-1375
This study aimed to investigate the effects of forward trunk lean on hamstring muscle kinematics during sprinting. Eight male sprinters performed maximal-effort sprints in two trunk positions: forward lean and upright. A three-dimensional musculoskeletal model was used to compute the musculotendon lengths and velocity of the biceps femoris long head, semitendinosus, and semimembranosus muscles during the sprinting gait cycle. The musculotendon lengths of all the three hamstring muscles at foot strike and toe-off were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. In addition, a positive peak musculotendon lengthening velocity was observed in the biceps femoris long head and semimembranosus muscles during the late stance phase, and musculotendon lengths at that instant were significantly greater during the forward trunk lean sprint than during the upright trunk sprint. The present study provides significant evidence that a potential for hamstring muscle strain injury involving forward trunk lean sprinting would exist during the stance phase. The results also indicate that the biceps femoris long head and semimembranosus muscles are stretched during forward trunk lean sprinting while contracting eccentrically in the late stance phase; thus, the elongation load on these muscles could be increased. 相似文献
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Jorge Cottyn Dirk De Clercq Jean-Louis Pannier Geert Crombez Matthieu Lenoir 《Journal of sports sciences》2013,31(2):157-164
Abstract The purpose of the present study was to investigate competitive anxiety during balance beam performance in gymnasts. Competitive anxiety was assessed continuously by heart rate monitoring and by retrospective self-report of nervousness in eight female national level gymnasts during their balance beam routine during one competition and two training sessions. A significant negative correlation was found between the score of the retrospective self-report of nervousness and performance during the routine. There were no significant differences in performance score by the judges between the three test sessions. There were also no differences in the retrospective self-report of nervousness. However, heart rate was significantly higher during the competition session than during the training sessions. The potential value of the retrospective report of nervousness for the study of critical events during gymnastic performance is illustrated. The results are discussed in the light of catastrophe theory. 相似文献
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Abstract Two studies determined the effects of responding to questions on heart rate (HR), rating of perceived exertion (RPE), and time to voluntary exhaustion on a graded treadmill walking/running test in naive college students. The first study used 16 (8 female and 8 male) volunteers; each subject was tested both without talking and while responding to 3 questions during each exercise stage. The second study had independent groups (n = 10 females each): (1) no talking during the early exercise stages (two walking stages), but answering questions during the later (running) stages until exhaustion, and (2) answering questions during the walking stages, but not talking during the running stages. Differences between groups (.10 level) were determined by two-way ANOVA (talking/no talking; gender) and t test for independent groups, respectively. There were no gender/treatment interactions. Exercise tolerance, HR, and RPE were generally not affected by the tester asking subjects questions about subjects' physical activity habits, with the following exceptions: the first study found a lower HR response to light work when the subjects were responding to questions. In the second study, the subjects perceived the work to be harder with no talking during the second (walking) stage, and while talking during the third (running) stage. For subjects unaccustomed to exercise testing and not well known to the tester, it appears that the best test results occur when the tester talks to the subject during early stages of exercise, but not during moderate and heavy work. 相似文献
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中国男篮队员身体接触状态下技术运用质量分析 总被引：2，自引：0，他引：2
徐丰 《西安体育学院学报》2007,24(5):73-76
强身体对抗已成为现代篮球比赛的必然现象,是完成比赛的基础和支撑点,因此身体接触状态下技术运用质量也就成为技、战术发挥的有力保证。运用录像观察法、统计分析法对第15届世界男篮锦标赛中国队队员在身体接触状态下的主要技术运用质量进行分析,结果表明我国运动员的对抗技术运用同比赛对手存在着全方位的差距,反映出我国运动员在对抗意识、综合控制能力以及身体对抗时力量、速度素质等方面存在的缺陷。 相似文献
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为了解男子拳击运动员赛前训练期机能变化规律,对安徽省男子拳击队8名参加2013年全国运动会决赛的运动员进行连续6周的赛前训练生化指标监控。结果显示:1)安徽男子拳击运动员在本次赛前训练期的血红蛋白初期逐渐下降,中期明显回升,出发前达到最高水平;2)血尿素从第2周到第5周与第1周相比均有升高,每周变化幅度不大,赛前最后1周调整至较低水平;3)血清肌酸激酶在第3周和第5周出现两个高峰,呈"双峰"状态,赛前最后1周下降至平均水平;4)血清睾酮随运动负荷的变化呈阶段性变化,赛前最后1周回升到较高水平;5)每个优秀拳击运动员反应运动负荷和疲劳的各项指标波动范围各不相同,存在显著性差异。建议在进行具体评价时建立个人正常值参照系,训练和比赛中可进行比对,更客观地判断个体机能情况。 相似文献
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Roland van den Tillaar 《Journal of sports sciences》2016,34(20):1976-1982
The aim of this study was to compare the active and passive range of motion (ROM) of the glenohumeral external rotation with the maximal external rotation and throwing performance during different throws with different wind-up techniques in elite team handball players. Twenty-two elite team handball players participated in the study in which the maximal ball release velocity and maximal external rotation during standing, with run-up and jump throws with two types of wind-ups were measured together with the maximal active and passive glenohumeral ROM of the external rotation, lying supine on a bench. Higher maximal external rotation was found during the throws with the whip-like wind-up in comparison to circular-like wind-up throws together with a lower external rotation during the active ROM test. No correlations were found between the ROM of the external rotation with the maximal ball release velocity and the maximal external rotation measured during the throws. It was concluded that ROM of the external rotation measured on the bench does not give any information about the maximal throwing performance or the external rotation angle during throwing and therefore cannot be used to identify potential fast throwers or injuries in elite team handball players. 相似文献
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在一个月经周期中,女性体内激素和对物质代谢调节的变化对于运动能力有一定影响。关于月经周期对葡萄糖代谢动力学的研究发现,黄体期葡萄糖Ra和Rd降低,而且女性在卵泡期要比在黄体期耐力性运动的运动能力更为强一些。通过补糖可以使这种差异减小,建议女运动员如果在黄体期参加运动,尤其是耐力性运动,要注意保证摄入充足的糖。 相似文献
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The purpose of the present study was to investigate competitive anxiety during balance beam performance in gymnasts. Competitive anxiety was assessed continuously by heart rate monitoring and by retrospective self-report of nervousness in eight female national level gymnasts during their balance beam routine during one competition and two training sessions. A significant negative correlation was found between the score of the retrospective self-report of nervousness and performance during the routine. There were no significant differences in performance score by the judges between the three test sessions. There were also no differences in the retrospective self-report of nervousness. However, heart rate was significantly higher during the competition session than during the training sessions. The potential value of the retrospective report of nervousness for the study of critical events during gymnastic performance is illustrated. The results are discussed in the light of catastrophe theory. 相似文献
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跳远起跳阶段摆动腿摆动的运动学特征及对起跳效果的影响 总被引：13，自引：2，他引：11
采用 JVC高速摄像系统对参加第 4届城市运动会 (1999,西安 )男子跳远比赛前 10名运动员起跳过程摆动腿动作运动学特征及对起跳效果的影响进行分析。研究表明 ,摆动腿摆动技术在跳远起跳过程中对增加身体重心垂直速度起着重要作用 ;我国男子跳远运动员在起跳过程中摆动腿摆动速度在蹬离地面至最大缓冲阶段角速度不断增加 ,蹬伸阶段角速度为零 ,其特征与运动生物力学有关原理相符 ;与国外优秀男子跳远运动员相比 ,我国男子跳远运动员起跳瞬间摆动腿摆动时机晚、速度慢、摆动幅度较小 ,从而影响了起跳效果 ,这是影响跳远成绩提高的原因之一。 相似文献