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141.
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
142.
The analysis of sport performance in competitive contexts has become synonymous with the use of a range of software applications and hardware e.g. heart rate monitors and gps systems. With the prevalence of technology in mind, a small but growing corpus of literature has begun to consider this phenomenon and its influence upon the coaching process. This study adds to this literature by detailing the autoethnographic experiences of a case study coach; Derek. A contextualised and richly described narrative account of Derek’s experience of using coaching applications is provided. Analysis of Derek’s narrative suggests that technology can be a useful means by which individuals make sense of their experience. Specifically, (1) technology can be a ‘ready-to-hand’ instrument that enhances the coaching process. Unfortunately, (2) technology may become the only and ‘calculative’ means by which individuals come to understand their performance. In such instances, it is important to note that (3) the videos we use to understand our performance are transformed and incomplete representations of lived athletic experiences. Thus, Derek’s story illustrates how technology can be both an enabler and barrier to athletes who wish to holistically understand their own lived experiences and engage in coach-athlete relationships. The accompanying analysis draws upon concepts from Heideggerian philosophy to add insight into the use of technology within the coaching process. In so doing, the study prompts coaches to critically view their coach-athlete relationships as situated in a wider world which contains, and can be mediated by, technology. In addition, Derek’s story (re)directs researchers and coaching practitioners interested in technology to a useful literature (philosophy of technology) which may further inform their understanding of coach-athlete relationships.  相似文献   
143.
High Intensity Interval Training (HIIT) can be performed with different effort to rest time-configurations, and this can largely influence training responses. The purpose of the study was to compare the acute physiological responses of two HIIT and one moderate intensity continuous training (MICT) protocol in young men. A randomised cross-over study with 10 men [age, 28.3?±?5.5years; weight, 77.3?±?9.3?kg; height, 1.8?±?0.1?m; peak oxygen consumption (VO2peak), 44?±?11?mL.kg?1.min?1]. Participants performed a cardiorespiratory test on a treadmill to assess VO2peak, velocity associated with VO2peak (vVO2peak), peak heart rate (HRpeak) and perceived exertion (RPE). Then participants performed three protocols equated by distance: Short HIIT (29 bouts of 30s at vVO2peak, interspersed by 30s of passive recovery, 29?min in total), Long HIIT (3 bouts of 4?min at 90% of vVO2peak, interspersed by 3?min of recovery at 60% of vVO2peak, 21?min in total) and MICT (21?min at 70% of vVO2peak). The protocols were performed in a randomised order with ≥48 h between them. VO2, HRpeak and RPE were compared. VO2peak in Long HIIT was significantly higher than Short HIIT and MICT (43?±?11 vs 32?±?8 and 37?±?8?mL.kg?1.min?1, respectively, P?P?P?2, HR and RPE than Short HIIT and MICT, suggesting a higher demand on the cardiorespiratory system. Short HIIT and MICT presented similar physiologic and perceptual responses, despite Short HIIT being performed at higher velocities.  相似文献   
144.
为了丰富户外用品上市公司的评价研究,提升企业的经营绩效,以我国户外用品6家上市公司2016年度财务数据为样本,采用熵权法从偿债能力、运营能力、盈利能力和成长能力四个纬度,对其进行了综合评价。结果显示:(1)公司经营结构中,偿债能力所占的权重最大,运营能力次之,盈利能力排名第三,成长能力所占权重最小;(2)6家公司中,4项一级指标的评分存在明显的两极分化现象。其中,三夫户外的偿债能力最强,牧高笛最弱;牧高笛的运营能力和盈利能力最突出,三夫户外的运营能力和嘉麟杰的盈利能力比较薄弱;中潜股份的成长能力最优秀,浙江永强成长能力最小;(3)综合实力强弱顺序依次为探路者、三夫户外、牧高笛、中潜股份、嘉麟杰、浙江永强。  相似文献   
145.
从国家和地方政策可以发现,体育产业集聚已成为中国体育产业发展的趋势。 然而体育产业集群作为一个复杂的网络主体,其发展与政府固然分不开,其内部组织结构、关系网络的优化才是集群优化的重点。研究创新构建了“网络特征—主体能力—企业绩效”理论模型,客观地揭示了变量之间的关系,并定量地证明了各变量间的相互作用。统计结果显示:体育产业集群的网络结构和网络关系对企业主体有直接的积极影响。体育企业的主体在网络规模与企业绩效、关系实力和企业绩效、关系质量和企业绩效之间具有明显的中介效应,在网络密度与企业绩效、网络开放性和企业绩效之间不具有中介效应。体育企业的主体获取和利用其他实体的资源并将其应用于生产过程将有助于提高企业绩效,对企业绩效的影响最大。研究对政府和体育企业层面分别提出了规范市场秩序、促进网络建设以及增进知识共享、提高网络质量等管理建议。  相似文献   
146.
Objective:We recently showed that the gender detection tools NamSor, Gender API, and Wiki-Gendersort accurately predicted the gender of individuals with Western given names. Here, we aimed to evaluate the performance of these tools with Chinese given names in Pinyin format.Methods:We constructed two datasets for the purpose of the study. File #1 was created by randomly drawing 20,000 names from a gender-labeled database of 52,414 Chinese given names in Pinyin format. File #2, which contained 9,077 names, was created by removing from File #1 all unisex names that we were able to identify (i.e., those that were listed in the database as both male and female names). We recorded for both files the number of correct classifications (correct gender assigned to a name), misclassifications (wrong gender assigned to a name), and nonclassifications (no gender assigned). We then calculated the proportion of misclassifications and nonclassifications (errorCoded).Results:For File #1, errorCoded was 53% for NamSor, 65% for Gender API, and 90% for Wiki-Gendersort. For File #2, errorCoded was 43% for NamSor, 66% for Gender API, and 94% for Wiki-Gendersort.Conclusion:We found that all three gender detection tools inaccurately predicted the gender of individuals with Chinese given names in Pinyin format and therefore should not be used in this population.  相似文献   
147.
程华  赵祥 《科研管理》2008,29(2):37-43
政府科技资助的绩效已经引起国内外学者的极大关注。本文基于文献研究,建立影响企业R&D投入的实证模型,采用浙江省民营科技企业数据,测度了政府科技资助对企业R&D投入的影响。进一步,分别从企业规模、研发强度、资助强度等不同视角研究政府科技资助的激励效应,探索政府科技资助的激励机理,研究发现:政府科技资助对企业滞后一年的R&D投入有显著促进作用;企业规模越大,政府科技资助激励效果越好;政府科技资助强度越大,激励效果越好;企业研发强度影响政府科技资助激励企业R&D投入。  相似文献   
148.
刘华 《中国软科学》2002,(10):26-30
本文从激励创新和促进经济增长两个方面考证专利制度的绩效,在理论论证的基础上,就中国专利制度运行中的相关数据进行了全面的实证分析。结论表明,专利制度的绩效与制度的完善程度是关联的,现阶段对我国专利制度的完善应重视对原创性技术的倾斜及对专利技术商业化环境的完善。  相似文献   
149.
基于交易费用理论与资源依赖理论,本文利用中国深圳证券市场中小企业板上市的制造业企业的数据,采用多元回归的方法研究客户集中度对中小企业绩效的影响。结果表明,中小企业客户集中度对企业绩效有显著正向作用;关键客户议价力在客户集中度与企业绩效间的关系中具有部分中介效应;企业产品类别在客户集中度与企业绩效的关系中具有调节效应:工业品制造企业的客户集中度对企业绩效具有显著的正向影响,但这种影响在消费品制造企业中并不显著存在。研究结果对中小企业的市场发展具有指导意义。  相似文献   
150.
通过引入细菌觅食算法对投影指标函数进行优化,寻求最佳投影方向,构建了基于投影寻踪的社会组织绩效评估新方法。通过该模型可把社会组织绩效的多维多层指标综合成一维投影值,且值越大表示该社会组织绩效水平越高。根据投影值大小可对社会组织绩效水平进行合理的分级评价。实例结果表明,基于细菌觅食算法的投影寻踪评估模型效果很理想,其优化时间及投影函数值分别为传统投影寻踪技术的38.3%和136.5%,具有较强的操作性和应用性,适用于社会组织绩效评估。  相似文献   
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