Test–retest reliability of a battery of field-based health-related fitness measures for adolescents

Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.     

Alterations in Strength and Maximal Oxygen Uptake Consequent to Nautilus Circuit Weight Training

Abstract

The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O ₂ max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ^?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O ₂ max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O ₂ max expressed in L · min ^?1 (10.9 and 11.4%), ml · kg ^?1 · min ^?1 (10.8 and 11.7%), and ml · kgLBW ^?1 · min ^?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals.     

运动员核心力量训练的本质

对核心力量训练在备战2008-2012年奥运会、亚运会和全运会实践研究后发现：1)运动员核心力量训练主要由核心稳定性训练、关节养护性训练及核心专门性训练组成;2)核心稳定性是指核心肌群在神经肌肉系统、骨骼韧带系统以及呼吸调节系统的协同作用下,稳定身体姿势和重心、产生和传递上下肢力量的能力;3)关节养护性训练是指针对易伤部位和薄弱环节所进行以伤病防护为主的体能训练理念和方法;4)核心稳定性与关节养护性训练是进行核心专门性力量训练的前提和基础;5)核心专门性力量训练是核心力量训练的本质和关键,是指根据专项动作模式的特殊需求以及运动员体能特点来进行的具有专项针对性核心力量训练,也即运动员的动态稳定性和强大的腰髋收缩力量。     

针对职业体能教学的高职体育课程改革探析

该文运用文献资料法、问卷调查法、数理统计法和实验对比法,在高职体育课程改革中进行了教学实验研究。结果表明:实验班的学生在体质测试成绩,选择课外体育锻炼项目和频度,对职业体能的认识及预防职业病等方面与对照班有明显差异。     

对参加北京奥运会蹦床比赛的16名世界优秀女子蹦床运动员竞技实力的分析

采用比赛现场统计、资料分析、调研考察等方法对2008年北京奥运会预选赛前16名世界优秀女子蹦床运动员的竞技实力进行分析。结果表明:规定动作是决定运动员预赛能否顺利进入前8名的基础和条件保证;整套动作的"精细化"程度、动作位移是我国选手规定动作尚需加强之处;自选动作与主要竞争对手仍有差距,主要表现在动作难度低于对手,难度实力欠缺;世界优秀运动员自选动作难度的使用表现出一定的规律性;进一步"细化"规定动作,突出"完美性",适度提高成套动作难度是备战阶段要解决的主要问题。     

竞技武术套路运动员力量素质的训练措施分析

在现代竞技武术比赛中,超强的力量素质对创造优异的运动成绩起着重要作用。本文通过文献资料法、逻辑分析法等方法,针对竞技武术套路的运动特点指导和制定科学合理的力量素质训练方法,旨在使竞技武术套路训练走向更加科学化和规范化的道路,以期促进我国武术事业的发展。     

纯电动汽车动力系统参数匹配与优化研究

基于某款纯电动汽车整车性能要求进行了关键部件的参数匹配,通过搭建CRUISE模型在NEDC工况下的仿真验证了参数匹配的合理性。基于ISIGHT和CRUISE联合仿真,以续驶里程为优化目标,以主减速比和动力电池的并联电池组数为优化变量,采用NSGA-II算法进行了优化分析,优化结果显示,此款纯电动汽车续驶里程得到了有效提升,且动力性也满足预定要求。     

图书馆群体成员结构分析

研究图书馆的群体结构对于人力资源的科学组织、利用,搞好读者服务工作,充分开发群体动力具有十分重要的意义,提出图书馆群体心理结构分析。     

The effect of television viewing on ethnic prejudice against immigrants: A study in the Italian context

Television viewers construct many different meanings from the programs they watch. Here, we investigated whether ethnic prejudice is differentially influenced by the genre of television programs in their portrayal of ethnic minorities. We also wanted to determine whether a higher educational level reduces ethnic prejudice and television use. A self-reported questionnaire was administered to 401 Italian adults. Structural equation modeling was used to analyze the relationships between ethnic prejudice and television program contents and educational level. Viewing Reality and Variety Shows was positively related to ethnic prejudice, News and Public Affairs was negatively related, and Films and TV series had no apparent influence on prejudice. Educational level was negatively related to both ethnic prejudice and watching Reality and Variety Shows, and positively related to viewing News and Public Affairs and Films and TV series programs.     

基于层次—因子综合评价法的广东省科技综合实力实证研究

分析科技综合实力的构成要素,建立相应的科技综合实力评价指标体系,构建基于层次-因子综合评价法的评价模型,并对广东省科技综合实力进行了逐年评价.广东省科技综合实力评价结果不仅反映出广东省科技综合实力发展趋势,而且为广东省科技综合实力的提高提供了决策支持.