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。     

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.     

水泥粉煤灰固化滩涂淤泥的强度与固化机理研究

为进一步揭示滩涂淤泥固化土的强度特性及其影响因素,对以沿海滩涂淤泥为原料土、水泥-粉煤灰作为主固化剂配置固化而成的滩涂淤泥固化土的强度特性与固化机理进行了试验研究。通过无侧限抗压强度试验,详细探讨了水泥、粉煤灰、减水剂、石灰、石膏、三乙醇胺、硫酸钠、氯化钠等主固化剂和外掺剂对滩涂淤泥固化土强度特性的影响,分析了固化剂和外掺剂对提高固化土强度的机理。结果表明:龄期以及水泥、减水剂、石灰、石膏、粉煤灰、三乙醇胺、硫酸钠和氯化钠等的掺量均对固化土的强度有影响。水泥和粉煤灰掺量越多,固化土的强度越高,而外掺剂,如减水剂、石灰、石膏、三乙醇胺、硫酸钠和氯化钠的掺量存在临界值。在临界值内,固化土的强度随外掺剂的掺量的增加而增加,超过该值后,则随外掺剂掺量的增加而减小。龄期对固化土的强度有较大影响,7 d龄期下的固化土的强度要远小于28 d时的强度。     

蜂窝纸板疲劳性能的研究

本文对蜂窝纸板疲劳性能进行了尝试性的试验研究,得到了蜂窝纸板的S-N曲线,同时了解了频率对蜂窝纸板疲劳寿命的影响,从而对蜂窝纸板包装运输方案的设计提供一定的依据。     

中国西部竞技体育综合实力研究

通过文献调研、专家访谈、比较分析等方法,以东部上海市为参照对象,对我国西部竞技体育的综合实力进行分析.在实力表现上,四川和陕西处于西部领先地位,但与上海相比还有较大差距.西部地区竞技体育后备人才、优秀运动员、教练员、竞技体育投入等指标的情况与其实力表现指标的情况具有相似的特征比例.地区经济水平落后、体育普及程度低是制约西部竞技体育综合实力提升的重要原因.