Corticospinal changes induced by fatiguing eccentric versus concentric exercise

The present study assessed neuromuscular and corticospinal changes during and after a fatiguing submaximal exercise of the knee extensors in different modes of muscle contraction. Twelve subjects performed two knee extensors exercises in a concentric or eccentric mode, at the same torque and with a similar total impulse. Exercises consisted of 10 sets of 10 repetitions at an intensity of 80% of the maximal voluntary isometric contraction torque (MVIC). MVIC, maximal voluntary activation level (VAL) and responses of electrically evoked contractions of the knee extensors were assessed before and after exercise. Motor evoked potential amplitude (MEP) and cortical silent period (CSP) of the vastus medialis (VM) and rectus femoris (RF) muscles were assessed before, during and after exercise. Similar reductions of the MVIC (?13%), VAL (?12%) and a decrease in the peak twitch (?12%) were observed after both exercises. For both VM and RF muscles, MEP amplitude remained unchanged during either concentric or eccentric exercises. No change of the MEP amplitude input–output curves was observed post-exercise. For the RF muscle, CSP increased during the concentric exercise and remained lengthened after this exercise. For the VM muscle, CSP was reduced after the eccentric exercise only. For a similar amount of total impulse, concentric and eccentric knee extensor contractions led to similar exercise-induced neuromuscular response changes. For the two muscles investigated, no modulation of corticospinal excitability was observed during or after either concentric or eccentric exercises. However, intracortical inhibition showed significant modulations during and after exercise.     

Temporal trends in 6-minute walking distance for older Japanese adults between 1998 and 2017

BackgroundThe 6-minute walking distance (6MWD) is an excellent measure of both functional endurance and health. The primary aim of this study was to estimate temporal trends in 6MWD for older Japanese adults between 1998 and 2017; the secondary aim was to estimate concurrent trends in body size (i.e., height and mass) and self-reported participation in exercise/sport.MethodsAdults aged 65–79 years were included. Annual nationally representative 6MWD data (n = 103,505) for the entire period were obtained from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Temporal trends in means (and relative frequencies) were estimated at the gender–age level by best-fitting sample-weighted linear/polynomial regression models, with national trends estimated by a post-stratified population-weighting procedure. Temporal trends in distributional variability were estimated as the ratio of coefficients of variation.ResultsBetween 1998 and 2017 there was a steady, moderate improvement in mean 6MWD (absolute = 45 m (95% confidence interval (95%CI): 43–47); percent = 8.0% (95%CI: 7.6%–8.4%); effect size = 0.51 (95%CI: 0.48–0.54)). Gender- and age-related temporal differences in means were negligible. Variability in 6MWD declined substantially (ratio of coefficients of variation = 0.89, 95%CI: 0.87–0.92), with declines larger for women compared to men, and for 75–79-year-olds compared to 65–74-year-olds. Correspondingly, there were moderate and negligible increases in mean height and mass, respectively, and negligible increases in the percentage who participated in exercise/sport at least 3 days per week and at least 30 min per session.ConclusionThere has been a steady, moderate improvement in mean 6MWD for older Japanese adults since 1998, which is suggestive of corresponding improvements in both functional endurance and health. The substantial decline in variability indicates that the temporal improvement in mean 6MWD was not uniform across the distribution. Trends in 6MWD are probably influenced by corresponding trends in body size and/or participation in exercise/sport.     

应用健康信念模式提高大学生体育锻炼的参与性

目的:应用健康信念模式教育对大学生体育锻炼的态度和大学生参与体育锻炼的积极性进行调查研究.方法:选取2012级排球班学生90名.分为实验组45名,对照组45名.实验组运用健康信念模式进行健康教育干预,对照组按常规方式进行健康教育.干预前后对两组进行统计分析.结果发现,进行健康信念模式教育的学生对体育锻炼的态度和体育锻炼的依从性与常规教育方式相比,都具有显著性差异(p<0.05).结论,应用健康信念模式教育可明显提高大学生对体育锻炼的态度,提高大学生参加体育锻炼的依从性.     

从刻蚀电路板废液中制取硫酸铜的工艺研究

研究了以刻蚀电路板废液为原料制取硫酸铜的工艺条件。探讨了Fe3 的干扰,不同的pH以及不同浓度的NaOH和H2SO4对产品质量的影响。结果表明:采用15%~20%NaOH与20%H2SO4可使产品的回收率达92%,产品纯度可达98%。     

探索中国《易》文化哲学思想中的运动健康原理

中华民族的古老哲学中以《易》文化最为璀璨,《易》文化中探寻了宇宙中天体的运行规律,然后经验的总结出这些天体运行对地球以及人类的巨大影响,提出人类在体育运动中要遵循一定的天体运行原理和自然变化原理才能够获得人类自身的健康和发展的哲学思想.从易文化中阐述的五大行星运行、春夏秋冬四季运行和月球运行对人体的影响中割析了人体体育运动要遵循的运动原理,总结出人体在从事体育运动时要在一定的时间遵循一定的运动原理才能达到人体正负能量的交替滋长,达到身体的和谐和健康发展.     

体力活动与癌症生存研究的10大问题

摘要：今天的美国有1 400万的癌症存活者,其中的很多存活者中都接受了多种治疗,包括手术、放疗、化疗、靶向治疗等。这些治疗能够延长生存时间,但同时也会带来很多急慢性的副作用,危害健康,影响生活质量。体力活动（PA）与癌症生存这一领域发展迅速,主要研究PA对癌症患者的影响。基于该领域的研究进展,提出了以下10大研究问题：1）PA能够降低癌症复发风险、和/或提高存活吗？2）PA能够影响癌症治疗决策、完成率、和/或患者对治疗的反应吗？3）癌症存活者的最佳运动处方是什么？4）静坐少动行为对癌症存活者有何影响？5）癌症存活者最有效的体力活动干预方案是什么？6）哪些癌症会影响病人对PA的反应？7）癌症存活者进行体力活动时需要注意的安全问题有哪些？8）哪些具体的癌症症状可以由PA解决？9）对于癌症晚期患者,体力活动还有何作用？10）如何将体力活动研究结果转化到临床和社区肿瘤实践中来？上述问题的回答至关重要,这不仅关系到体力活动和癌症存活这一研究领域的发展,更重要的是,能够为每年数百万新诊断为癌症的病人、正在接受癌症治疗的病人、治疗结束处于恢复中的病人或是那些正在与晚期癌症抗争的病人带来福音。     

有氧运动调节驱动蛋白改善AD模型皮层线粒体轴突转运

摘要：目的：观察8周有氧运动对AD小鼠皮层线粒体顺向轴浆转运驱动蛋白的影响。方法：清洁级4月龄APP/PS1、C57BL/6J小鼠各40只随机分为安静组和运动组,运动组进行8周跑台运动,5 d/w,60min/d,前10min负荷15m/min,后50min负荷18m/min,坡度为0。透射电镜观察皮层额叶、颞叶线粒体形态和数目变化;Western blot检测皮层额叶、颞叶线粒体驱动蛋白重链（Kinesin heavy chain,KHC）、驱动蛋白轻链1（Kinesin light chain 1,KLC1）、驱动蛋白轻链2（Kinesin light chain 2,KLC2）表达量。结果：1）电镜下C57正常对照组皮层突触、线粒体结构清晰完整,线粒体数目较多且分布均匀;8周的有氧运动使异常线粒体数目呈减少趋势。电镜下可见安静组APP/PS1小鼠皮层出现神经毡结构松散,少见典型的突触结构,线粒体肿胀、膜破裂,异常线粒体的数目较多;8周的有氧运动改善其突触结构,可见排列整齐的突触小泡增多,异常线粒体数目有所减少。2）安静组APP/PS1组小鼠皮层额叶、颞叶KHC、KLC1、KLC2表达较正常对照组均减少（P<0.05）;8周的有氧运动显著提高皮层额叶KHC、KLC1、KLC2和颞叶KHC、KLC1的表达。结论：8周有氧运动可以通过上调APP/PS1小鼠皮层线粒体顺向转运马达蛋白Kinesin重链和轻链的表达,减轻线粒体顺向轴浆转运障碍,增加线粒体在突触的分布,改善突触的结构和功能,是运动改善APP/PS1小鼠行为学的分子机制之一。     

规律运动干预人类衰老过程的表观遗传学机制研究进展

摘要：人类的衰老过程受DNA编码信息、表观遗传学信息和环境因素的共同调控。DNA编码信息提供了合成生命所必需蛋白质的模板或蓝图,决定着人类的生命历程和最高寿限,而表观遗传学信息则提供了何时、何地以及如何应用DNA编码信息的指令。饮食、药物、体力活动等诸多环境因素可通过改变衰老相关基因的表观遗传学修饰,进而影响基因的开启与关闭,决定着个体寿命的长短。表观遗传学不但搭建起了环境—基因之间的桥梁或中介,而且把人类的寿限与寿命密切地联系在一起。规律运动作为一种环境表观遗传调制器,可在不影响DNA编码的前提下,通过诱导表观遗传学修饰改变调控衰老相关基因的表达水平,在延缓人类衰老进程中发挥着重要作用。本文从影响人类衰老过程的表观遗传调控机制入手,对规律运动在调控衰老过程端粒相关蛋白、脑衰老、糖脂代谢和肿瘤发生发展的表观遗传学机制研究进展进行综述,其目的在于从分子遗传学水平揭示运动干预延缓衰老之谜,为倡导通过增加体力活动实现健康老龄化提供科学依据。     

中国成年人广播体操发展走向及成套动作编排特征研究

运用文献资料法和录像分析法对自 1951 年以来我国颁布的9套成年人广播体操进行统计分析,结果表明:(1)成年人广播体操遵循了系列化、层次化、大众化的创编原则,成套动作的结构符合人体生理心理规律,注重普及性和实效性;(2)成年人广播体操成套动作结构总体上呈单一逐渐过度到复杂再到简单的变化趋势;(3)成年人广播体操的动作姿势有19种类型,其空间特征呈现立体化、多样化和方位化,强调人体大关节参与运动,重视上下肢、头颈、躯干各关节之间的相互协调;(4)成年人广播体操中肩带肌群参与运动的频数明显高于其他主要肌群,上肢肌肉群的负荷偏大.     

离心运动适应机制—肌节重塑与炎症反应关系的研究进展

目的:研究延迟性肌肉酸痛(DOMS)与炎症反引发的关系.方法:文献综述法.内容:运动员训练过程中,不习惯的离心运动均导致延迟性肌肉酸痛(DOMS).普遍认为离心运动导致的损伤和炎症反应诱发了DOMS.然而,近来的研究不支持此假说,DOMS起因的观点受到质疑.通过离心运动性肌节重塑过程,及整合钙离子依赖性蛋白水解酶作用的相关文章进行综述研究,证实离心运动导致骨骼肌损伤和炎症反应.结论:肌节重塑过程为我们科学训练提供了新思路.