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1.
了解壳聚糖对大鼠耐力运动中自由基代谢的影响。大鼠进行4周跑台耐力训练,以0.5g kg壳聚糖灌胃,测定骨骼肌和肝脏线粒体中丙二醛(MDA)和活性氧的含量。结果表明:服药组与运动组比较骨骼肌和肝脏线粒体中MDA含量显著降低(P<0.05);服药组骨骼肌活性氧含量显著低于运动组(P<0.05);肝脏活性氧没有明显的变化。壳聚糖能有效地减轻运动所产生的内源性自由基对大鼠的伤害,增强大鼠运动能力,延缓疲劳的发生。  相似文献   

2.
肌球蛋白作为骨骼肌纤维内主要的收缩蛋白和调节蛋白,对于骨骼肌纤维的收缩特性起重要作用,肌球蛋白重链是肌球蛋白重要组成,它有多种亚型表达,不同亚型收缩特性存在显著差异,研究发现,当外界刺激条件变化时,骨骼肌纤维肌球蛋白重链亚型组成可以改变,骨骼肌纤维收缩特性在肌球蛋白重链组成改变时发生显著变化,因此,研究不同运动条件下骨骼肌纤维肌球蛋白重链组成的变化对于深刻理解运动影响骨骼肌收缩性能具有重要意义。  相似文献   

3.
有氧运动与氧化物介导的调节   总被引:8,自引:0,他引:8  
有氧运动过程中内源性活性氧的生物学作用已被人们广泛关注,有氧力竭运动中产生的内源自由基可经诱导线粒体膜通透性转变孔道(PTP)的出现,PTP影响线粒体的跨膜电位,进而对细胞的发育产生作用。有氧运动训练诱发的活性氧通过NF-kB等转录因子调节细胞的表达及线粒体的生物发生过程。因此耐力运动训练的适应过程与其内涵性氧化物介导的调节关系密切。  相似文献   

4.
一、超等长训练简介 骨骼肌是人体运动的动力,从一定意义上讲,运动训练就是对骨骼肌(与支配他的神经系统)的强化和协调。骨骼肌的收缩方式包括动力性和静力性收缩两大类。动力性收缩又包括肌肉的离心收缩、向心收缩和超等长收缩(plyometrics)三种方式。超等长收缩就是指同一骨骼肌先进行离心收缩,紧接着进行向心收缩的肌肉收缩方式。  相似文献   

5.
胰岛素样生长因子- I 对骨骼肌生长和修复研究进展   总被引:1,自引:0,他引:1  
生长激素(GH)/胰岛素样生长因子-I(IGF-I)轴是肌肉生长的重要调节因子之一。虽然许多组织都能表达IGF-I,但它们各自的功能不同。骨骼肌是IGF—I的靶器官,同时也分泌IGF—I。骨骼肌组织表达的IGF—I对骨骼肌损伤后的再生、修复非常重要,也是通过适当干预保持肌肉质量的重要调节因素。主要讨论GH/IGF—I在促进骨骼肌再生和修复中的作用,并讨论其在运动康复中的应用前景。  相似文献   

6.
近来,骨骼肌葡萄糖转运的细胞信号转导机制研究十分活跃,但运动刺激骨骼肌葡萄糖转运的信号机制尚不明了。文章就运动刺激骨骼肌葡萄糖转运的胰岛素信号转导途径和非胰岛索信号转导途径两大方面的研究进展进行了综述(重点在非胰岛素途径),并对二者的交叉作用作简要介绍,以促进对运动调节骨骼肌葡萄糖转运信号转导机制的深入研究。  相似文献   

7.
验证收缩骨骼肌细胞葡萄糖转运蛋白4(GLUT4)基因的表达在转录水平上是否受转录抑制子Ⅱ型HDAC5蛋白(简写为HDAC5)的调节。研究运用运动模拟信号5-氨基-4-甲酰胺咪唑核糖核苷酸(AICAR)和HDACs抑制剂SCRIPTAID孵育骨骼肌细胞。用蛋白印迹技术测定HDAC5蛋白表达,定量RT-PCR法检测GLUT4 mRNA表达。与无AICAR的对照组相比,AICAR组骨骼肌细胞内HDAC5减少了29%,并伴随有124% GLUT4 mRNA的增加,但肌细胞内HDAC5的蛋白总量无变化;使用HDACs抑制剂SCRIPTAID刺激骨骼肌细胞能够明显增加核心组蛋白乙酰化水平和上调GLUT4基因的表达。这些结果提示,通过AICAR和SCRIPTAID分别减少或抑制核HDAC5均能上调骨骼肌细胞GLUT4基因的转录,HDAC5可能在转录水平上对肌肉收缩引起的GLUT4基因的表达起着重要的调节作用。  相似文献   

8.
关于运动与骨骼肌钾泄漏研究的综述   总被引:2,自引:0,他引:2  
马强 《体育科学》1993,13(4):76-79
人们虽然对骨骼肌运动疲劳进行了广泛的研究,但疲劳机制至今仍不甚清楚。一个世纪以前,Mosso 认为,运动疲劳源于神经的疲劳。但以后 Merton 的研究表明,疲劳时,运动神经和神经一肌肉接头处的信号传导维持正常。Jones、Bigland-Ritchie、Hultman 和 Spriet 等分别证明,直接电刺激疲劳的骨骼肌,不能使其产生正常的收缩强  相似文献   

9.
就运动中活性氧诱导肌原性IL-6产生的机制等问题做综述。IL-6是运动过程中变化非常明显的一种细胞因子,其变化幅度与运动时间和运动强度关系密切。研究表明,运动中生成的IL-6主要来源于收缩的骨骼肌,骨骼肌在运动过程中产生的自由基,尤其是活性氧是运动中诱导IL-6产生的一个主要原因。  相似文献   

10.
绿茶活性提取物对有氧性运动疲劳恢复的作用   总被引:3,自引:0,他引:3  
分析绿茶活性提取物对优秀赛艇和足球运动员有氧性运动疲劳后血清尿素(BU)含量、血清丙二醛(MDA)含量、血清肌酸激酶(CK)、血清超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH—PX)活性的变化,表明绿茶活性提取物对骨骼肌损伤有抑制和修复作用,同时有效减少运动所造成的机体结构蛋白和功能蛋白的分解,以及通过直接清除氧自由基及其代谢产物、增强运动员机体抗氧化酶活力等机制,提高机体的抗氧化能力,减少过量自由基对机体的损伤作用,加速对剧烈有氧运动产生的自由基的清除,从而促进机体运动性疲劳恢复。  相似文献   

11.
In the past, contraction-induced production of reactive oxygen species (ROS) has been implicated in oxidative stress to skeletal muscle. As research advances, clear evidence has revealed a more complete role of ROS under both physiologic and pathologic conditions. Central to the role of ROS is the redox signaling pathways that control exercise-induced major physiologic and cellular responses and adaptations, such as mitochondrial biogenesis, mitophagy, mitochondrial morphologic dynamics, antioxidant defense, and inflammation. The current review focuses on how muscle contraction and immobilization may activate or inhibit redox signalings and their impact on muscle mitochondrial homeostasis and physiologic implications.  相似文献   

12.
The first report demonstrating that prolonged endurance exercise promotes oxidative stress in humans was published more than 4 decades ago. Since this discovery, many ensuing investigations have corroborated the fact that muscular exercise increases the production of reactive oxygen species (ROS) and results in oxidative stress in numerous tissues including blood and skeletal muscles. Although several tissues may contribute to exercise-induced ROS production, it is predicted that muscular contractions stimulate ROS production in active muscle fibers and that skeletal muscle is a primary source of ROS production during exercise. This contraction-induced ROS generation is associated with (1) oxidant damage in several tissues (e.g., increased protein oxidation and lipid peroxidation), (2) accelerated muscle fatigue, and (3) activation of biochemical signaling pathways that contribute to exercise-induced adaptation in the contracting muscle fibers. While our understanding of exercise and oxidative stress has advanced rapidly during the last decades, questions remain about whether exercise-induced increases in ROS production are beneficial or harmful to health. This review addresses this issue by discussing the site(s) of oxidant production during exercise and detailing the health consequences of exercise-induced ROS production.  相似文献   

13.
田径运动中肌肉收缩速度力量分析及其训练原理探讨   总被引:4,自引:0,他引:4  
通过对田径运动中肌肉收缩速度力量分析,提出了提高运动员专项速度力量的训练原理。力量训练时,必须根据各个专项运动的肌肉收缩速度与力量特性、肌肉收缩的力学规律、肌肉不同收缩速度的神经肌肉特点等规律,对运动员采用适度提高肌肉大力量能力,以提高肌肉抗中等负荷速度力量能力和快速能力等力量训练,最终实现肌肉的最快速度收缩所产生的力量提高。  相似文献   

14.
通过高速摄影、表面肌电图(sEMG)测量以及等速肌力测试等方法对12名体育专业男生进行研究,获取踝关节主要屈伸肌(胫骨前肌和腓肠肌)等速肌力与sEMG之间的关系,以此说明用sEMG来直接评价肌肉用力情况时需进行标准化的必要性及最佳标准化方式。结果表明:相同肌肉收缩过程中,肌力矩值与平均振幅(MA)的变化趋势呈现高度相关,相关系数r在0.6以上;不同收缩形式、不同收缩速度下,均方根振幅(RMS)、积分肌电(iEMG)值会随着收缩速度的增加而减小;跳深动作下肢肌肉sEMG标准化后的值与跳深腾起速度之间均有一定的相关性,标准化后以最大随意等长收缩(MVIC)的标准化值与跳深腾起速度的相关性最高。  相似文献   

15.
Literature concerning the theoretical role of spinal reflex circuits and their sensorimotor signals in proprioceptive neuromuscular facilitation (PNF) muscle stretching techniques was examined. Reviewed data do not support the assertion commonly made in PNF literature that contraction of a stretched muscle prior to further stretch, or contraction of opposing muscles during muscle stretch, produces relaxation of the stretched muscle. Further, following contraction of a stretched muscle, inhibition of the stretch reflex response lasts only 1 s. Studies examined suggested that decreases in the response amplitude of the Hoffmann and muscle stretch reflexes following a contraction of a stretched muscle are not due to the activation of Golgi tendon organs, as commonly purported, but instead may be due to presynaptic inhibition of the muscle spindle sensory signal. The current view on the complex manner by which the spinal cord processes proprioceptive signals was discussed. The ability of acute PNF stretching procedures to often produce a joint range of motion greater than that observed with static stretching must be explained by mechanisms other than the spinal processing of proprioceptive information. Studies reviewed indicate that changes in the ability to tolerate stretch and/or the viscoelastic properties of the stretched muscle, induced by PNF procedures, are possible mechanisms.  相似文献   

16.
In this study, we used tensiomyography (TMG) to assess muscle status immediately after an ultra-endurance triathlon. Maximal radial displacement or deformation of the muscle belly, contraction time, delay time, sustain time, and relaxation time were measured for both legs, and dependent t-tests were used to compare means between the beginning and end of the race. The 19 men assessed (age 37.9 ± 7.1 years; height 177.5 ± 4.6 cm; weight: 73.6 ± 6.5 kg) participated in the 2009 edition of the Lanzarote Ironman. Deterioration in the neural response was observed for contraction time (P = 0.008) and relaxation time (P = 0.011), with a moderate decrease in the response time (sustain time) and a loss in muscle stiffness (deformation of the muscle belly). The effect of muscle fatigue on the rectus femoris and biceps femoris was different. Barely any changes in contraction time, relaxation time, sustain time, and deformation of the muscle belly were observed, while only the contraction response time decreased to a significant extent (reduction in delay time; P = 0.003). The considerable loss in contractile capacity induced by a long-distance race was reflected in changes in the neuromuscular response and fluctuations in the contractile capacity of the muscle. These modifications, derived from a prolonged, exhausting effort, can be assessed in a simple, non-aggressive, non-invasive way using tensiomyography.  相似文献   

17.
骨骼肌的某些生物力学特性   总被引:1,自引:1,他引:0  
本文的研究目的是寻找出负荷与肌肉力学特性之间的关系,对90例蛙坐骨神经──腓肠肌标本所作的研究表明;肌肉最大收缩力与负荷的大小成正比;肌肉收缩的最大加速度可能是个常数。  相似文献   

18.
Literature concerning the theoretical role of spinal reflex circuits and their sensorimotor signals in proprioceptive neuromuscular facilitation (PNF) muscle stretching techniques was examined. Reviewed data do not support the assertion commonly made in PNF literature that contraction of a stretched muscle prior to further stretch, or contraction of opposing muscles during muscle stretch, produces relaxation of the stretched muscle. Further, following contraction of a stretched muscle, inhibition of the stretch reflex response lasts only 1 s. Studies examined suggested that decreases in the response amplitude of the Hoffmann and muscle stretch reflexes following a contraction of a stretched muscle are not due to the activation of Golgi tendon organs, as commonly purported, but instead may be due to presynaptic inhibition of the muscle spindle sensory signal. The current view on the complex manner by which the spinal cord processes proprioceptive signals was discussed. The ability of acute PNF stretching procedures to often produce a joint range of motion greater than that observed with static stretching must be explained by mechanisms other than the spinal processing of proprioceptive information. Studies reviewed indicate that changes in the ability to tolerate stretch and/or the vis‐coelastic properties of the stretched muscle, induced by PNF procedures, are possible mechanisms.  相似文献   

19.
利用等动测力系统(Cybex-6000)对10名优秀女子自行车运动员进行踝关节肌力的等动向心测试。研究的结果表明:1)踝关节肌群等动向心收缩时峰力矩及相对峰力矩随运动速度的增加而减少,总功及相对总功随测试速度的增加而减小,而平均功率及相对值随测试速度的增加而增大;2)踝关节前后侧肌力矩相差很大,而且显示出速度的差异性。自行车运动员踝关节肌群的肌力特征,反映了踝关节的肌肉配布与踝关节肌群的训练特征,体现了其合肌肉规律,合肌群特色,合运动实际的规律。  相似文献   

20.
测定与分析了不同类型肌纤维在收缩过程中两种形式糖原(MG和PG)的分解状况。雄性Wistar大鼠分为2组:低糖组(LG)和高糖组(HG),灌注自由下肢和同时电刺激10min。收缩前后肌肉样本取自腓肠肌(SOL),外侧胫骨白肌(WG)和外侧胫骨红肌(RG)用以分析MG,PG和总糖原。结果表明:在电刺激收缩过程中,MG和PG同时作为底物被利用。在快收缩肌纤维(WG和RG)比慢收缩肌纤维(Sol)MG和PG分解明显增加。高糖组比低糖组MG和PG分解明显增加。不同类型肌纤维MG百分含量与总糖原浓度呈高度正相关。提示:肌纤维内MG的含量可能是糖原依赖性磷酸化速率机制的限制因素。  相似文献   

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