BMI和心肺适能对全代谢综合征男性最大脂代谢水平的影响

目的:探究BMI和心肺适能对全代谢综合征男性最大脂代谢水平的影响.方法:采用CDS代谢综合征诊断标准募集24名全代谢综合征(tMS)男性.血清指标检测采用酶法和放免法.直接测定最大耗氧量和最大有氧功.间接测热法和非连续递增负荷法检测最大脂代谢水平.分别依据BMI、最大耗氧量的平均值将被试分为高,低BMI组,高、低心肺适能组.结果:tMS男性整体最大脂氧化率(MFOR)为151.58±20.64 mg/min,最大脂氧化强度(Fatmax)为28.48±5.98%VO2max,Fatmax相应RER为0.94±0.01;供能交叉点为33.42±6.96%VO2max,心肺适能水平为18.25±2.68 ml/kg/mim;高、低BMI组间心肺适能、MFOR、Fatmax和交叉点均无显著性差异;高、低心肺适能组间MFOR具有非常显著性差异(P<0.01),但BMI、Fatmax和交叉点强度均无显著性差异;tMS男性BMI与MFOR相关不具显著性,心肺适能与MFOR具显著性正相关(r=0.75,P<0.01).结论:全代谢综合征男性最大脂氧化强度处于低有氧强度范围,tMS男性最大脂氧化率受心肺适能水平影响,而BMI对其无显著影响.     

Validity and reliability of a low-cost dynamometer to assess maximal isometric strength of upper limb

Muscle imbalance and deficit are key parameters for guiding rehabilitation and sports sessions and avoiding injuries. However, the high cost and non-portable nature of most instruments employed for muscle strength assessment frequently hamper an affordable evaluation in field conditions. This study evaluated the validity and reliability of a low-cost digital dynamometer to assess the maximal isometric strength of upper limb muscles. Fourteen physically active volunteers performed the main movements of the upper limb at maximal isometric strength: flexion-extension, internal-external rotation and abduction-adduction of the shoulder; and flexion-extension of both elbow and wrist. Validity was examined by comparing the strength values from the low-cost digital dynamometer and those measured by an isokinetic dynamometer, assumed as the gold standard. The correlation between both devices was perfect (r > 0.913), while Bland-Altman plots showed absolute agreement between both devices, the maximum range of the values of bias was ?0.99–1.00 N in wrist extension. Inter-tester and intra-tester reliability were excellent for all movements (ICC ≥ 0.855). The low-cost digital dynamometer showed strong validity and excellent reliability in assessing maximal isometric strength during the main movements of the upper limb. Professionals may use it for an affordable isometric muscle strength assessment in field situations.     

停止课外训练对小学女生最大心率的影响

以探讨小学生最大心率水平和停止课外训练对小学生最大心率的影响为目的。采取的方法是在跑台上运用Bruce法对停训8周前后的8名小学女生最大心率进行比较,并运用文献资料法,对比国内外学者在停训前后最大心率的研究。结果表明,小学女生停训前后的最大心率、运动能力均无显著差异;用传统的220-年龄推算最大心率可能不准确。     

科学训练概念的界定及若干理论问题的再认识

运动训练的发展是一个由低到高不断深化的过程,解析科学训练内涵,阐明科学训练的实质、核心,并在此基础上,对科学训练的概念进行了初步界定,对科学训练与大运动量负荷训练、经验训练以及运动训练科学化的关系进行了理论辨析,指出训练中应抓好对全局有长远影响的关键因素,充分利用现有条件并努力创造条件,不断提高科学训练水平,实现运动训练科学化。     

Reprints from the Research Quarterly

Abstract

The purpose of this study was to determine the effects of intensified physical education sessions on adolescents ages 11–16 years. They were divided into two experimental groups—high-intensity running group (HIRG) and high-intensity jumping group (HIJG)—and a control group (C). During the sessions, heart rate (HR) was monitored. There was no significant difference between mean HR for HIRG and HIJG, while the mean HR was significantly lower for C (p < .001). For both HIRG and HIJG, the mean HR was significantly higher for girls than for boys (p < .001). Our results suggested that these intensified physical education lessons require a high percentage of maximal HR in adolescents and can be used to improve aerobic fitness.     

非正则图的Laplacian特征值与特征向量

本文研究了非正则图的Q-矩阵的最大特征向量分量的最大比值,应用这个结论得到了非正则图的Laplacian特征值的一个上界,从而改进了Stevanovic的结论.     

缩图与扩图

在图的研究中,要用数学归纳法证明图的属性,就必须知道n阶图与n+1阶图的关系。删边并点的收缩运算在树的讨论中起到很大的作用。对于运算的逆,则称之为“扩”。文中对多边形、极大平面图,采用不同的“缩”与“扩”,证明了极大平面图是4-面可着色。     

高校女生12min跑取代800m跑体能测试方法的可行性研究

目的：对最大摄氧量和氧脉搏同800m跑、12min跑成绩的相关性作探讨,以确定哪种方法更适合作为高校普通大学生体育课体能测试的评定方法。方法：研究对象为太原理工大学20名普通在读大二女生。运用意大利科时迈（COSMED）公司生产的quarkb2型运动心肺功能测试系统测得受试对象的最大摄氧量。在标准的400m田径场上分别测得受试对象12min跑和800m跑成绩。运用SPSS11.0统计软件对测试结果进行数据处理。结果：①女生12min跑成绩同最大摄氧量绝对值、最大摄氧量相对值和氧脉搏成低度正相关。②女生800m跑成绩同最大摄氧量绝对值、最大摄氧量相对值和氧脉搏成低度负相关。结论：12min跑比800m跑更适合用于评定高校普通大学女生有氧能力的体能测试方法。     

足球课外锻炼对改善大学生身体机能水平的实验研究

近年来大学生身体机能水平普遍呈逐年下降的趋势,尤其心肺功能水平下降最为明显。本文运用试验方法对足球课外锻炼能否改善大学生心肺功能进行了研究,通过对学生分组并进行12分钟跑的测试,对比锻炼前后的最大摄氧量来检验锻炼效果。结论是通过科学的足球课外锻炼对于不同组别的大学生都是可以有效地改善大学生的心肺功能水平的。     

时延和功耗约束无线传感器网络连通支配集算法

针对无线传感器网络虚拟骨干时延和功耗的约束问题,提出（α,β）-约束的连通支配集算法．根据（α,β）-约束定义了时延约束的连通支配树问题（CDTT）,并给出构建同时符合时延约束和有限总功率消耗的连通支配树（CDT）算法．算法分为2个阶段执行：首先在单位圆图上构建网络的极大独立集,然后在无向图上基于不同权值的最小生成树和最短路径树,构造满足（α,β）-约束要求的支撑树．理论分析和仿真结果表明提出的算法能够正确地解决CDTT问颢,并能够构建平衡功率消耗和传输时延要求的无线传感器网络虚拟骨干．