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1.
大鼠骨骼肌模拟急性拉伤的生物力学实验研究 总被引：4，自引：1，他引：3
根据现有肌肉急性拉伤动物模型中存在的问题,即:拉伤前肌肉的机能水平低,拉伤过程中肌肉为静息状态、拉伸速率慢、拉伸幅度大等,结合运动实践,复制了肌肉急性拉伤动物模型,并从生物力学角度进行了研究,其结果如下:1)肌肉在收缩状态下拉伤(离心工作),能够影响肌肉中肌纤维与肌鞘(结缔组织)受损比例,结缔组织受损明显增加。2)肌肉的拉伸速率快,为300％的肌纤维长度/s,明显优于其它学者的模型(6.8％～68％)肌纤维长度/s),更好地模拟运动实践中肌肉急性拉伤的状况(400％肌纤维长度/s)。3)肌肉拉伸时的幅度小,为其肌腹长度的24％,在肌肉正常生理运动范围之内;这样不仅符合运动实践中肌肉离心收缩幅度小的特点,而且在模型中也避免了肌肉邻近关节受损的可能性,从而提高了模型的质量。 相似文献
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肌肉伤后静力训练对其材料力学性能影响的实验研究 总被引：3，自引：0，他引：3
采用动物实验法，对肌肉急性拉伤后自然修复和静力训练对肌肉材料力学性能的影响进行比较研究。结果表明：急性拉伤后自然修复肌肉其拉伸承载强度在24d基本恢复，30d后出现相对稳定状态；应变性能恢复较慢，若无外界干预较难恢复原有的应变性能；适量静力训练对肌肉伤后材料力学性能恢复有着积极的影响，大运动量静力训练则对其产生负面影响。 相似文献
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小腿肌急性拉伤是体育比赛和训练中的常见病、多发病。多见于田径、球类项目。他们大多数是在往返来回跑动中膝关节伸直时突然用力蹬地提踵所伤。与赛前或训练时准备活动不充分或受风寒肌肉发僵、过度疲劳,老年性缺钙有关。 打网球引起小腿肌肉急性拉伤的原因是直接或间接外力所致。小腿肌的腓肠肌、比目鱼肌、蹠肌因过度收缩或被突然拉长而往往致伤。小腿肌肉急性拉伤大 相似文献
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《上海体育学院学报》1996,(4)
肌肉拉伤有急性拉伤和微细拉伤的长期积累两大类原因。在体育运动中,肌肉的拉伤常与准备活动不当,肌肉的生理机能尚未达到运动所需的状态;训练水平不够,肌肉弹性、力量差;身体疲劳,动作准确性、协调性因肌肉力量下降而降低;技术动作错误或运动时注意力不集中;场地过滑、气温过低等因素有关。 相似文献
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骨骼肌伤后训练对其收缩力与松弛特性的影响 总被引：4，自引：1，他引：3
82只雄性SD大鼠为实验对象，对其小腿三头肌急性拉伤。随机分为自然修复组（实验对照EC）、牵张训练组（PT）、静力训练组（ST）和跑动训练组（MT）、分别于恢复期不同的时间测试腓肠肌的等长收缩力和应力松弛特性。结果发现：在体肌肉中，轻度拉伤早期收缩力的较大幅度的变化，炎性反应是其主要的影响因素，拉伤早期的收缩力恢复与其结构性修复存在着时程上的差异，这种时程方面的差异是肌肉重复损伤的重要原因，肌肉拉伤早期进行牵张训练，对肌肉的功能恢复产生负面影响，拉伤后期的牵张训练，对肌肉的功能性恢复与提高产生重要作用，大强度的跑动训练并没表现出训练效应累积。肌肉伤后静力训练对收缩力及松弛特性的恢复有着积极影响，大运动量的静力训练导致伤肌的功能性消退。 相似文献
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实验性骨骼肌伤后训练的形态计量学研究 总被引：2，自引：1，他引：1
对SD大鼠小腿三头肌急性拉伤后，进行自然修复组(EC)、牵张(PT)、跑动(MT)和静力(ST)4／11练等不同处理。实验结果表明：肌肉拉伤后自然修复过程表现伤面扩增、稳定和收缩3个时期：拉伤肌肉早期的牵张活动，对肌肉伤面修复产生负面影响。中、后期实施牵张练习能够加快修复的进程；跑动训练对肌肉修复有抑制效应并可使肌肉出现伤面累积，加剧损伤的程度；适度的静力训练能够促进肌肉的修复，大运动量的静力训练可致肌肉萎缩与变性。 相似文献
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在查阅国内外大量相关文献资料的基础上,对肌肉急性拉伤后材料力学的研究进展进行了归纳分析,如肌肉拉伤实验研究的动物模型,拉伤肌肉恢复过程中材料力学特性的变化等,并对该研究中存在问题及今后的发展,提出了看法。 相似文献
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肌肉急性拉伤后的生物力学研究现状 总被引：1，自引：0，他引：1
肌肉拉伤模型的建立为人们从生物力学和组织学深入研究提供了可能性。虽然国内的一些学者已建立了肌肉慢性拉伤(劳损)的动物模型,如吕丹云(1982)、于长隆和曲绵域等(1985),但他们只是进行了病理学和组织学研究而未进行生物力学研究。夏剑英(1987)建立了大鼠腓肠肌急性拉伤模型,用电刺激仪刺激腓肠肌两端,引起腓肠肌强直收缩,踝关节跖屈,与此同时,一重物从固定高度自由下落,以一个基本恒定的初始冲量,迫使踝关节迅速背屈被拉伤。Nikolaou(1987)用新西兰白兔的胫骨前肌建立了肌肉急性拉伤模型,采用10cm/ 相似文献
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骨骼肌急性拉伤后材料力学研究进展 总被引：2，自引：0，他引：2
在查阅国内外大量相关文献资料的基础上,对肌肉急性拉伤后材料力学的研究现状进行了归纳分析,如肌肉拉伤实验研究的动物模型、拉伤肌印次复过程中材料力学特性的变化等,并对该研究中存在的问题及今后的发展,提出了看法。 相似文献
11.
This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue. 相似文献
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Roy J. Shephard 《Journal of sports sciences》2013,31(7):603-620
The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae. 相似文献
13.
Alan M. Nevill Roger L. Holder Andrew Bardsley Helen Calvert Stephen Jones 《Journal of sports sciences》2013,31(4):437-443
A regression analysis of competitors' tournament results in relation to their world rankings was proposed to identify the effect of home advantage in international ‘grand-slam’ tennis and ‘major’ golf tournaments. The results provided little evidence of home advantage in either the grand-slam tennis or the golf tournaments held in 1993. The only possible evidence of home advantage was found in the Wimbledon tennis and the US Open golf championships. Even these findings can be explained, at least partially, by (1) the availability of information concerning the low world rankings of the British tennis players competing at Wimbledon, and (2) selective entry, allowing only the world's top-ranked foreign golfers into the US open golf tournament. In both cases, the lower ranking home competitors have a greater opportunity to perform above their anticipated world rankings. Therefore, provided entry into tennis and golf tournaments is truly ‘open’ to both the host nation's representatives and foreign competitors alike, home advantage does not appear to be a major factor influencing the competitors' performance in such competitions. These findings may be explained by the relatively objective nature of the scoring systems used in tennis and golf, unlike the subjective influence of refereeing decisions on the results of team-games such as soccer. 相似文献
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许良 《体育科技文献通报》2011,19(2):1-4
基于1985、1995和2005年全国学生体质调研数据,对各时期我国城乡学生形态、机能、体能发展水平进行系统地定量研究,动态分析20年全国城乡学生体质发展的特点与规律。主要研究结果：（1）近20年城乡学生生长发育持续提前,城市学生各项形态指标生长水平高于乡村,身高城乡差距缩小,体重、胸围城乡差距加大;（2）城市学生肺活量水平高于乡村,城乡学生肺活量20年持续下降,前10年乡村学生下降快、后10年城市学生下降快;（3）乡村学生800m、1000m跑水平高于城市,城市女生50m跑、仰卧起坐水平高于乡村,其他素质城乡学生水平波动较大;（4）城市女生50m跑20年持续下降,城乡学生800m和1000m跑、城市学生50m×8往返跑20年加速下降,其他素质20年间有增有降发展极不平稳。 相似文献
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采用测量、问卷调查、数理统计等方法,分析定向运动学习前后对大学生身心健康的影响.结果经T检验和x2检验且表明：定向运动不仅能增强学生体质健康水平,而且有助于学生的情绪调节,增强自信心与创新意识,培养勇敢顽强的意志品质,建立良好的人际关系,能有效地促进学生身心健康发展.为了全面提高大学生整体素质,积极实践,构建定向运动课内外一体化教学模式,进行定向运动课程模块化教学,以满足学生的多元化需求. 相似文献
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重新认识体育的社会关联 总被引：3，自引：1，他引：2
体育与政治之间存在一个悖论，体育的发展与经济实力之间没有直线相关，体育与教育部分重叠，体育与宗教最为近缘，体育可借用科学手段，体育的艺术禀性日益明显，体育与养生反映着两种人生观。 相似文献
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本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。 相似文献
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对全面把握游泳训练环节的探讨 总被引：4，自引：0，他引：4
从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。 相似文献