首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Morphology of the deltoid muscles in elite tennis players   总被引:1,自引:0,他引:1  
The aim of this study was to examine the deltoid muscle properties of the dominant and non-dominant arm of Greek professional male tennis players. Eight male tennis players (mean age 22.0 years, s = 3.2) were subjected to biopsy of the deltoid muscle of both arms. Adenosine triphosphate (ATPase) histochemistry and myosin heavy chain (MHC) composition were performed on the samples with homogenate electrophoresis. No significant differences were observed in the percentage of types I, IIa, IIab, and IIb muscle fibres between the deltoid muscles of the two arms. Types I, IIa, and IIx muscle fibres of the dominant and non-dominant deltoid muscles did not differ significantly for MHC isoform composition. Type IIab muscle fibres showed a similar cross-sectional area (CSA) percentage distribution between the two arms. The CSA percentage for types I, IIa, and IIb muscle fibers did not differ significantly between the dominant and the non-dominant arm. We conclude therefore that regular tennis training probably does not lead to any significant changes in the muscle fibre types of the dominant and non-dominant arms of elite tennis players.  相似文献   

3.
Abstract

The aim of this study was to examine the deltoid muscle properties of the dominant and non-dominant arm of Greek professional male tennis players. Eight male tennis players (mean age 22.0 years, s = 3.2) were subjected to biopsy of the deltoid muscle of both arms. Adenosine triphosphate (ATPase) histochemistry and myosin heavy chain (MHC) composition were performed on the samples with homogenate electrophoresis. No significant differences were observed in the percentage of types I, IIa, IIab, and IIb muscle fibres between the deltoid muscles of the two arms. Types I, IIa, and IIx muscle fibres of the dominant and non-dominant deltoid muscles did not differ significantly for MHC isoform composition. Type IIab muscle fibres showed a similar cross-sectional area (CSA) percentage distribution between the two arms. The CSA percentage for types I, IIa, and IIb muscle fibers did not differ significantly between the dominant and the non-dominant arm. We conclude therefore that regular tennis training probably does not lead to any significant changes in the muscle fibre types of the dominant and non-dominant arms of elite tennis players.  相似文献   

4.
骨骼肌纤维类型研究的新进展   总被引:2,自引:0,他引:2  
骨骼肌纤维类型和肌纤维蛋白同功型的多样性,以及在不同肌组织中的特定分布和构成比例,决定其对复杂功能的适应能力。骨骼肌纤维类型转变的研究为运动训练提供了理论基础。  相似文献   

5.
目的探讨高频正弦波振动(HFV)对制动大鼠比目鱼肌(SOL)梭内、外肌纤维肌球蛋白重链(MHC)表达的影响。方法采用大鼠后肢制动作为废用性肌萎缩动物模型,对振动组大鼠施以HFV,用免疫组化染色法检测大鼠SOL梭内、外肌纤维MHC表达。结果①制动14 d后,大鼠SOL梭外肌Ⅰ型肌纤维的构成比明显减少,Ⅱ型肌纤维的构成比明显增加(P<0.05),SOL梭内肌纤维快缩型MHC的表达有所增强;②制动加HFV大鼠与制动组相比,SOL梭外肌Ⅰ型肌纤维的构成比明显上升,Ⅱ型肌纤维的构成比明显下降(P<0.05),SOL梭内肌纤维快缩型MHC的表达没有明显变化。结论 HFV对制动大鼠SOL梭外肌Ⅰ型肌纤维向Ⅱ型肌纤维的转化和梭内肌MHC表达增强的趋势有明显的对抗作用。  相似文献   

6.
In this study, we examined the effect of muscle temperature (Tm) on adenosine triphosphate (ATP) and phosphocreatine utilization in single muscle fibres during the development of maximal power output in humans. Six male participants performed a 6-s maximal sprint on a friction-braked cycle ergometer under both normal (Tm = 34.3 degrees C, s = 0.6) and elevated (T(m) = 37.3 degrees C, s = 0.2) muscle temperature conditions. During the elevated condition, muscle temperature of the legs was raised, passively, by hot water immersion followed by wrapping in electrically heated blankets. Muscle biopsies were taken from the vastus lateralis before and immediately after exercise. Freeze-dried single fibres were dissected, characterized according to myosin heavy chain composition, and analysed for ATP and phosphocreatine content. Single fibres were classified as: type I, IIA, IIAX25 (1 - 25% IIX isoform), IIAX50 (26 - 50% IIX), IIAX75 (51 - 75% IIX), or IIAX100 (76 - 100% IIX). Maximal power output and pedal rate were both greater (P < 0.05) during the elevated condition by 258 W (s = 110) and 22 rev . min(-1) (s = 6), respectively. In both conditions, phosphocreatine content decreased significantly in all fibre types, with a greater decrease during the elevated condition in type IIA fibres (P < 0.01). Adenosine triphosphate content was also reduced to a greater (P < 0.01) extent in type IIA fibres during the elevated condition. The results of the present study indicate that after passive elevation of muscle temperature, there was a greater decrease in ATP and phosphocreatine content in type IIA fibres than in the normal trial, which contributed to the higher maximal power output.  相似文献   

7.
肌球蛋白重链是决定肌纤维收缩特性的主要因素,运动训练可造成肌球蛋白重链多种多样的改变,从而影响他们的速度或耐力。阐述了力量训练和耐力训练对肌纤维转型、肌纤维肥大、肌纤维增生的影响,及肌纤维特性改变的时相等大家所关注的问题。  相似文献   

8.
于桂林 《湖北体育科技》2013,(12):1060-1062
两类肌纤维LDH同功酶的差别在于不仅能决定它们的代谢方式,且红纤维的LDH可帮助白纤维在运动中产生其本身难以氧化的乳酸。因两类肌纤维肌球蛋白———ATP酶活性的差别,决定它们的收缩速度不同。又由于肌肉具有不同纤维类型相互转化的遗传潜力等,人体在发育中的分化问题和神经纤维类型的分化是否会受一定遗传控制。如果对这些问题都一并加以研究,将有助于更好地揭示两类肌纤维能否转化的问题。  相似文献   

9.
王海 《体育科技》2014,(5):74-75
通过文献综述法对不同信号调节肌纤维类型转换进行综述,结果表明:不同信号调节肌纤维类型转换作用机理是不同的;STIMI、FOXOI调节肌纤维类型转换,不具备导向性;而AIMPI、PGC-IQ促进II型向I型肌纤维转换,具有导向性;但肌纤维类型转换机制尚未阐释清楚还有待进一步进行研究。  相似文献   

10.
Abstract

In this study, we examined the effect of muscle temperature (T m) on adenosine triphosphate (ATP) and phosphocreatine utilization in single muscle fibres during the development of maximal power output in humans. Six male participants performed a 6-s maximal sprint on a friction-braked cycle ergometer under both normal (T m = 34.3°C, s = 0.6) and elevated (T m = 37.3°C, s = 0.2) muscle temperature conditions. During the elevated condition, muscle temperature of the legs was raised, passively, by hot water immersion followed by wrapping in electrically heated blankets. Muscle biopsies were taken from the vastus lateralis before and immediately after exercise. Freeze-dried single fibres were dissected, characterized according to myosin heavy chain composition, and analysed for ATP and phosphocreatine content. Single fibres were classified as: type I, IIA, IIAX25 (1 – 25% IIX isoform), IIAX50 (26 – 50% IIX), IIAX75 (51 – 75% IIX), or IIAX100 (76 – 100% IIX). Maximal power output and pedal rate were both greater (P < 0.05) during the elevated condition by 258 W (s = 110) and 22 rev · min?1 (s = 6), respectively. In both conditions, phosphocreatine content decreased significantly in all fibre types, with a greater decrease during the elevated condition in type IIA fibres (P < 0.01). Adenosine triphosphate content was also reduced to a greater (P < 0.01) extent in type IIA fibres during the elevated condition. The results of the present study indicate that after passive elevation of muscle temperature, there was a greater decrease in ATP and phosphocreatine content in type IIA fibres than in the normal trial, which contributed to the higher maximal power output.  相似文献   

11.
跳远运动员髋关节振动力量训练效果的研究   总被引:1,自引:1,他引:0  
对10 名跳远专项二级运动员进行振动力量训练。研究表明:在刺激频率为30~35Hz,加速度25~30 m/s2 条件下,经过8 周系统的振动力量 训练,试验组髋关节的屈伸肌群与对照组屈肌肌群最大功增长都非常明显,表现出髋关节屈肌最大功比试验前有显著性地提高,试验组髋关节 屈伸肌最大功增长幅度比对照组屈伸肌最大功幅度大。试验组髋关节伸肌对照组屈伸肌峰力矩前4 周比后4 周增长幅度大,后4 周增长幅度有 所减缓,试验组后4 周髋关节屈伸肌峰力矩增长幅度比对照组高。髋关节伸肌相对峰力矩力量增长幅度比屈肌要大。  相似文献   

12.
文章以文献资料法,数理统计法和综合分析为主要研究方法,围绕运动训练能否导致骨骼肌纤维类型转这一有争议话题,阐述目前对此问题的两种不同观点及其实验证据,以及运动训练对骨骼肌纤维产生的影响,以使读者对当前纤维类型与遗传和运动训练关系研究状况有所了解,并具同时阐述了自己的一些观点。  相似文献   

13.
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   

14.
Abstract

Plantar flexion and knee extension fatigue patterns elicited by 25 serial isometric contractions were assessed on eight female distance runners. Fiber type composition of the vastus lateralis and gastrocnemius muscles was examined by a needle biopsy technique. Two different isometric exercise regimens were administered: 10-sec contractions separated by 5-sec intertrial rest (10:5) designed to elicit a rapid rate of fatigue, and 10-sec contractions separated by 20-sec intertrial rest (10:20) designed to induce less fatigue. No fatigue pattern was found for the 10:20 regimen which was consistent with previous data on male distance runners but unlike male power athletes who did exhibit significant fatigue. Significant fatigue decrements were found for the 10:5 knee extension (55.7%) and plantar flexion (75.8%) conditions. Fiber type composition and fatigue decrements did not correlate. Knee extension and plantar flexion maximum strength correlated significantly with the amount of fatigue induced with r's of .82 and .83, respectively. For each separate muscle group, maximum isometric strength was a better predictor of fatigability than fiber type composition. Even though differences in maximal strength and muscle mass existed between knee extension and plantar flexion muscle groups, elicited fatigue curves were similar in pattern differing only in absolute level. High versus low strength classification analysis showed similar knee extension but dissimilar plantar flexion fatigue patterns. Results suggest that the role of fiber type composition, muscle mass, and maximum strength level as they influence local muscular fatigue patterns must be elucidated for each muscle group separately.  相似文献   

15.
目的:探讨正弦波振动(HFV)对制动大鼠肌肉萎缩的对抗作用。方法:以大鼠后肢制动为废用模型,对振动组大鼠施以不同频率的HFV,观察大鼠比目鱼肌(SOL)湿重体重比、肌纤维横截面积、梭外肌纤维构成比以及梭内肌纤维肌球蛋白重链(MHC)的表达的变化。结果:(1)制动14 d后,SOL湿重体重比、肌纤维横截面积以及梭外肌Ⅰ型肌纤维的构成比明显下降,Ⅱ型肌纤维的构成比明显增加,梭内肌纤维MHC的表达有所增强;(2)施加HFV后,SOL湿重体重比、肌纤维横截面积和Ⅰ型肌纤维的构成比明显上升,Ⅱ型肌纤维的构成比明显下降,梭内肌纤维MHC的表达正常。结论:HFV可对抗废用后SOLⅠ型肌纤维向Ⅱ型肌纤维的转化和梭内肌MHC表达有增强的趋势,且以200 Hz HFV组最为显著。  相似文献   

16.
神经肌肉接头(neuromuscular junction,NMJ)作为运动神经元与骨骼肌之间的突触连接,一生中持续经历重构过程。NMJ的形态学变化可受肌体活动程度的影响并与年龄及肌纤维类型相关。目前,国内大部分相关研究主要集中在运动对骨骼肌整体及肌纤维类型的影响,而有关运动对NMJ形态影响的报道较少。就国外有关各种运动形式下NMJ产生的形态学适应性变化的研究予以综述。  相似文献   

17.
为了解肌肉疲劳时神经肌肉系统兴奋性的变化规律,以10名健康男子为对象,采用随意性最大的肌肉收缩(V组)和电刺激诱发肌肉收缩(E组)的两种运动形式,对足背屈运动引起胫骨前肌疲劳时的胫骨前肌和比目鱼肌的表面肌电图(sEMG)和诱发肌电图(evoked EMG)进行了观察。结果发现:(1)V组和E组的sEMG积分值和平均频率均出现了降低的趋势,而且E组的变化较为明显;(2)E组的胫骨前肌(主动肌)Mmax和H/Mmax明显降低下,比目鱼肌(拮抗肌)Mmax和H/Mmax在胫骨前肌疲劳后则无明显变化;(3)V组胫骨前肌与比目鱼肌的H/Mmax在疲劳发生后均表现出显著低下,但二者的Mmax却无明显变化。结论:肌疲劳时不但主动肌脊髓运动神经元受到了抑制,拮抗肌脊髓运动神经元也受到了类似的影响,但由于肌肉收缩方式不同而上述变化并不完全一致。  相似文献   

18.
Tennis     
This study investigated the effect of the larger diameter (Type 3) tennis ball on performance and muscle activation in the serve. Sixteen male advanced tennis players performed serves using regular size and Type 3 tennis balls. Ball speed, surface electromyography, and serve accuracy were measured. There were no significant differences in mean initial serve speeds between balls, but accuracy was significantly greater (19.3%) with the Type 3 ball than with the regular ball. A consistent temporal sequence of muscle activation and significant differences in mean activation of different muscles were observed. However, ball type had no effect on mean arm muscle activation. These data, combined with a previous study, suggest that play with the larger ball is not likely to increase the risk of overuse injury, but serving accuracy may increase compared to play with the regular ball.  相似文献   

19.
Abstract

Skeletal muscle tissue was obtained from the vastus lateralis of six normal college male students. Two biopsies were obtained prior to, and one following the training period. Two subjects performed isotonic leg extensions, two performed isometric leg extensions, and two ran up and down stadium bleachers. All training periods lasted 8 weeks. Muscle tissue was processed immediately for electron microscope examination. The following parameters were measured from micrographs of longitudinal sections: sarcomere length, sarcomere width, A band length, I band length, intracellular fat globule quantity and diameter, mitochondria length, mitochondria quantity, and Z band width. The following parameters were measured from micrographs of cross sections: myosin fiber concentration, distance between myosin filaments, myosin filament diameter, and actin filament diameters. Observations were also made on the geometric arrangement of the filaments, glycogen, and gross myofibrillar structure. Major findings were: there are between 7 and 11 actin fibers in “orbit” around each myosin fiber, increased glycogen and intracellular fats, greater mitochondria length, decreased myosin density, and an increase in myosin fiber diameter.  相似文献   

20.
This study investigated the effect of the larger diameter (Type 3) tennis ball on performance and muscle activation in the serve. Sixteen male advanced tennis players performed serves using regular size and Type 3 tennis balls. Ball speed, surface electromyography, and serve accuracy were measured. There were no significant differences in mean initial serve speeds between balls, but accuracy was significantly greater (19.3%) with the Type 3 ball than with the regular ball. A consistent temporal sequence of muscle activation and significant differences in mean activation of different muscles were observed. However, ball type had no effect on mean arm muscle activation. These data, combined with a previous study, suggest that play with the larger ball is not likely to increase the risk of overuse injury, but serving accuracy may increase compared to play with the regular ball.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号