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1.
本研究通过量表信效度检测、设计量表、相关性分析,以北京工业大学本科女生群体作为调查对象,探究本科女生体育锻炼与其学习效率是否具有相关性。最终通过数据分析得到,本科女生体育锻炼与其学习效率成正相关性,故基于"线上线下"、"课上课下"角度一级北京工业大学校园资源建设的实际情况,提出相对应的措施来促进北京工业大学本科女生体育锻炼水平,进而提升其学习效率。  相似文献   
2.
ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.  相似文献   
3.
目的考察适应性完美主义、自主动机对青少年锻炼坚持性的综合影响,检验父母自主支持的调节效应。方法修订父母社会背景调查问卷(家长报告)的自主支持分量表、中文Frost多维度完美主义问卷的个人标准和条理性分量表、因果控制点知觉量表和青少年户外运动坚持性量表,对2230名12~18岁青少年及其家长进行调查,分析适应性完美主义对青少年锻炼坚持性的间接影响。结果父母自主支持、青少年的适应性完美主义和自主动机对锻炼坚持性正向影响皆显著,分别解释了3.7%、30.3%和38.3%的变异;在适应性完美主义与青少年锻炼坚持性的影响链条上,自主动机的中介效应、父母自主支持的中介调节效应、性别的调节中介效应皆显著,三者共同的间接效应值为0.426,占总效应的77.45%。结论适应性完美主义既能直接影响青少年的锻炼坚持性,又能通过自主动机的中介而间接作用于锻炼坚持性;父母对青少年体育锻炼的自主支持能够对青少年的适应性完美主义和锻炼自主动机产生积极的调节作用;相较于女性青少年,男性青少年的锻炼自主动机更强烈、锻炼亦更具坚持性。  相似文献   
4.
Researchers are often interested in establishing equivalence of population variances. Traditional difference-based procedures are appropriate to answer questions about differences in some statistic (e.g., variances, etc.). However, if a researcher is interested in evaluating the equivalence of population variances, it is more appropriate to use a procedure designed to determine equivalence. A simulation study was used to compare novel equivalence-based tests to traditional variance homogeneity tests under common data conditions. Results demonstrated that traditional difference-based tests assess equality of variances from the wrong perspective and that the proposed Levene-Wellek-Welch test for equivalence of group variances the best performing test for detecting equivalence. An R function is provided in order to facilitate use of this test for equivalence of population variances.  相似文献   
5.
Purpose: There is currently no standardized testing protocol for assessing clients’ fitness/health within the Australian fitness industry. This study examined the perceptions of the feasibility of using a standardized testing protocol among Australian fitness industry professionals. Method: In 2014, 1,206 registered fitness industry professionals (aged 17–69 years) completed an online survey. Perceived feasibility for using a standardized testing protocol was assessed based on responses to 6 items. Respondents were classified as having a high level of perceived feasibility if they reported all 6 items to be “definitely feasible.” A multivariate logistic regression analysis, adjusting for demographic and fitness industry-related factors (e.g., qualification/years of experience), assessed the likelihood of having a high level of perceived feasibility. Results: Overall, 25.5% (95% CI [23.1%, 28.0%]) of the sample perceived the use of a standardized testing protocol as highly feasible. Items ranked most often as “definitely feasible” were “undertaking training to use the protocol” (55%) and “conducting follow-up testing every 6 to 12 weeks” (52%). After adjustment for the effect of confounding factors, casually employed professionals (OR = 0.63; 95% CI [0.45, 0.90]) and group instructors (OR = 0.58; 95% CI [0.41, 0.82]) were less likely to perceive standardized testing protocols as highly feasible. Conclusions: Among a large sample of Australian fitness industry professionals, slightly more than a quarter perceived using a standardized testing protocol to be highly feasible. Group instructors and casual employees perceived lower feasibility. Further research should determine the barriers to implementing a standardized testing protocol across the fitness industry.  相似文献   
6.
目的:探讨动态视力在不同类型体育项目间的发展特征,为体育锻炼改善视力的应用研究提供依据。方法:选取6~10岁无专门体育训练经历的在校学生和参加足球、乒乓球、跆拳道、空手道、游泳、体操等项目的俱乐部或体校学生,共603名。使用动态视力检测仪和标准对数视力灯箱测量动态视力和静态视力。计算动静比(动态视力/静态视力),并将其作为衡量动态视力发展水平的指标。结果:6~7岁是动态视力发展的敏感期(P<0.05),8岁、10岁男性儿童的动静比高于女性儿童,且差异有统计学意义(P<0.05)。校外体育练习组的动静比高于普通在校学生组(P<0.05),开放性运动项目的动静比高于闭锁性运动项目(P<0.05)。结论:参加体育锻炼对动态视力的发展有积极的影响,且不同运动项目的影响效果不同。  相似文献   
7.
目的:探讨不同负荷运动训练对大鼠骨骼肌线粒体三羧酸循环的影响及其机制。方法:将雄性Wistar大鼠50只随机均分为5组:安静对照组(C)、低负荷运动训练组(LT)、中等负荷运动训练组(MT)、高负荷运动训练组(HT)和极高负荷运动训练组(ST),每组10只。各运动组分别进行6周的跑台运动训练。训练方案结束后,取腓肠肌样本,提取线粒体,测定线粒体柠檬酸合成酶(CS)、异柠檬酸脱氢酶(ICD)和α-酮戊二酸脱氢酶(α-KGDHC)活性;线粒体Ga2+含量、胞浆NADH、NAD+、ATP和ADP含量,以及ICD mRNA转录水平。结果:(1)不同负荷运动训练组线粒体CS、ICD和α-KGDHC的活性均显著高于安静对照组(P < 0.01),且CS和ICD活性由高到低顺序均为:MT组 > HT组 > ST组 > LT组 > C组,α-KGDHC活性由高到低顺序为:HT组 > MT组 > ST组 > LT组 > C组。(2)不同负荷运动训练组线粒体Ca2+ 含量均显著高于安静对照组(P < 0.01),其含量由高到低顺序为:MT组 > HT组 > ST组 > LT组 > C组;胞浆NADH/NAD+和ATP/ADP的比值均显著低于安静对照组(P < 0.01),其比值由低到高顺序为:MT组 < ST组 < HT组 < LT组 < C组。(3)不同负荷运动训练组ICD mRNA转录水平均高于安静对照组(P < 0.01),其水平由高到低顺序为: MT组 > HT组 > ST组 > LT组 > C组。结论:低负荷、中等负荷、高负荷及极高负荷运动训练均可提高大鼠骨骼肌线粒体三羧酸循环功能,且中等负荷运动训练效果最佳。其机制与胞浆NADH/NAD+和ATP/ADP比值、线粒体摄钙能力及限速酶基因的表达有关。  相似文献   
8.
This paper surveys the prevalence and correlates of anabolic androgenic steroids (AAS) use among Norwegian adolescents, and examines the degree to which sports participation is a mediating or moderating factor to well-known correlations between AAS use and problem behaviour. The data come from the “Ungdata” study, a cross-national youth survey system offered to all municipalities in Norway (response rate: 74%, N?=?77,572). The study demonstrates a lifetime prevalence of AAS use of 1.27% and a higher prevalence among boys (1.81%) than girls (0.76%). The analyses show that AAS use is clearly related to problem behaviour such as violence and other substance use. When controlling for problem behaviour, there are no correlations between AAS use and exercising in a sports club or on one’s own, whilst there is a weak positive correlation between AAS use and exercising in a gym or engaging in other forms of physical exercise such as dancing or martial arts. These patterns are more or less the same for boys and for girls. We conclude that adolescent AAS use is a low-prevalence phenomenon that primarily takes place in smaller subgroups of individuals who engage in other forms of problem behaviour as well.  相似文献   
9.
Purpose: An advanced system for the assessment of climbing-specific performance was developed and used to: (a) investigate the effect of arm fixation (AF) on construct validity evidence and reliability of climbing-specific finger-strength measurement; (b) assess reliability of finger-strength and endurance measurements; and (c) evaluate the relationship between finger flexor all-out test scores and climbing ability. Methods: To determine the effect of AF, 22 male climbers performed 2 maximal strength and all-out tests with AF (shoulder and elbow flexed at 90°) and without AF (shoulder flexed at 180° and elbow fully extended). To determine reliability, 9 male climbers completed 2 maximal strength tests with and without AF and an all-out and intermittent test without AF. Results: The maximal strength test without AF more strongly determined climbing ability than the test with AF (r2 = .48 and r2 = .42 for sport climbing; r2 = .66 and r2 = .42 for bouldering, respectively). Force and time variables were highly reliable; the rate of force development and fatigue index had moderate and low reliability. The maximal strength test with AF provided slightly higher reliability than without AF (intraclass correlation coefficient [ICC] = 0.94, ICC = 0.88, respectively). However, smaller maximal forces were achieved during AF (484 ± 112 N) than without AF (546 ± 132 N). All-out test average force had sufficiently high reliability (ICC = 0.92) and a relationship to sport climbing (r2 = .42) and bouldering ability (r2 = .58). Conclusion: Finger strength and endurance measurements provided sufficient construct validity evidence and high reliability for time and force parameters. Arm fixation provides more reliable results; however, the position without AF is recommended as it is more related to climbing ability.  相似文献   
10.
Assessing comfort of running footwear reliably is challenging. The purpose of this study was to compare the intra-rater reliability between different assessment types, to calculate intra-individual reliability scores and to evaluate the effect of rater selection based on individual reliability scores on group level reliability. Three assessment types: ranking, Visual Analogue Scale (VAS), and Likert Scale (LS) were provided twice in six separate sessions among 30 participants, who assessed comfort of five shoes after treadmill running. Spearman's rho provided an evaluation of inter-session relative reliability and typical error as a measure of absolute reliability for each assessment type. Ranking (r?=?0.70, 95% confidence interval [CI] 0.61–0.78) yielded the highest relative reliability for overall comfort, followed by VAS (r?=?0.67, 95% CI 0.56–0.75) and LS (r?=?0.63, 95% CI 0.52–0.72), with large-scale overlaps of CIs between assessment types. The same order of assessment types was found for the percentage of reliable raters (r?≥?0.7) with 60% in ranking scale, 47% in VAS and 37% in LS. Forming subgroups corresponding to the intra-individual reliability substantially increased group level reliabilities. Based on measures of relative reliability, an extreme reduction in resolution as provided by the ranking from pairwise comparisons seems to be a valuable tool in footwear comfort assessments if assessment time is of minor importance. No preference can be provided for the two investigated rating scales. Besides the assessment type, a selection of the best raters in additional reliability checks seems to be a prerequisite for further comfort-related studies.  相似文献   
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