共查询到20条相似文献,搜索用时 93 毫秒
1.
本文在某核电厂二号机组凝汽器失去1/6的循环冷却水后,通过对相关运行参数变化的分析,讨论了凝汽器失去1/6循环冷却水之后,机组主要参数的变化趋势和对机组效率的影响,并根据分析计算得出导致机组效率降低的根本原因所在。 相似文献
3.
<正> 1.发队码牌。第一节室外课整理队形完毕后,教师发队码牌,牌上用二个数字表示学生在队列中的位置:如第一列排头生的队码牌为“一.1”,第一列第二名为“一.2”,依此类推。 2.互相“照像”,认清相邻同学。发放队码牌后,做一些游戏性辅助练习,以强化效果。“照像”游戏的方法是:第一排的同学向后 相似文献
4.
在多年体育教学中,笔者非常重视开始部分的队列练习,而且特别重视加强每节课准备活动前的体操队型散开练习,培养了学生的团队意识。具体方法是采用正步走散开的方法(简称分列式)。其具体做法是:四列横队站队,由排头向排尾连续报数,每人要记住自己所报的数。分列式走的方法是第一排向前走七步、第二排走五步、第三排走三步、第四排走一步。排与排走时间隔两步,就是前一排走完两步后,后一排再走,最后四排是同时立定。立定后四排同时向左转,变成四路纵队。这时所有学生按刚才的连续报数所报的数×2-1得的数,走纵队的散开(如某人… 相似文献
5.
6.
7.
<正>一、男女生在队伍中的站位问题:班级男女生排列成四列横队时,一些教师往往把男生排在前面、女生排在后面,也有的恰好相反,到底哪个是正确的呢?提示:从生理的角度来看,中学男生身高偏高些、女生较矮些。因此,一般情况下,班级男女生排列成四列横队时,前两排为女生,后两排为男生。后排高些,前排低些,便于学生观察、听讲,因此,将个子相对男生矮些的女生安排在前排是一贯的做法。从管理的角度讲,女生的纪律性较强,站在前面,有助于给后排的男生以榜样作用。因此,女生站在前 相似文献
8.
9.
九十九、有接应一打一射门 (1) 按图99所示的位置在半场中标出A、B两点,队员分列于此。 (2) 练习开始,B列第一人2号将球传给A列的第一人1号,然后立即回防,制止1号带球进入和射门。1号遇2号阻截,如难以越过,可将球传给A列或B列的第二名(即 相似文献
10.
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
12.
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.
14.
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
15.
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
16.
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
17.
18.
影响和限制耐力性运动项目的成绩的生理因素是复杂的和多方面的,取决于训练的强度和运动成绩.大强度持续性运动可导致呼吸肌疲劳.运动性呼吸疲劳可能在决定运动耐量方面起到关键的作用:一方面通过直接影响运动肌力量的生成(外周疲劳),另一方面,通过肢体用力自感不安反馈引起工作肌运动单位输出功率下降(中枢疲劳).对呼吸肌进行训练,可能有助于提高耐力性项目的运动成绩. 相似文献
19.
结合欧洲足球技战术的发展特点,就鲁能泰山足球队的体能训练、技术训练、防守阵型、进攻方式、定位球、职业态度、球星培养等诸方面所存在的不足进行了分析,提出相应的改进意见。 相似文献
20.
朱新新 《体育科技文献通报》2010,18(3):52-53,57
本文运用文献资料法,逻辑分析法,在遵循逻辑学、哲学、心理学原理的前提下,对竞技健美操技术的概念进行了界定,对竞技健美操技术进行了分类研究,在此基础上分析了竞技健美操技术的结构,为系统、科学的组织竞技健美操的教学和训练提供理论上的参考,为促进竞技健美操理论体系的完善和协调发展做出一定的贡献。 相似文献