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51.
ABSTRACT

Introduction: Low energy availability (LEA) results in physiological adaptations, which can contribute to unfavourable health outcomes. Little information exists on risk of LEA in active individuals competing in different sports or levels of competition. The aims of this study were to (1) identify risk of LEA in females competing at different levels of competition and (2) investigate associations between risk of LEA, illness and dietary habits. Methods: The validated questionnaire, ‘Low Energy Availability in Females Questionnaire’ was distributed online (November 2016–February 2017) to assess risk of LEA. Twenty-nine additional questions collected information on demographics, illness history and dietary habits. Participants were considered at risk of LEA if they attained a score of?≥?8 and were grouped into: (i) international; (ii) provincial/inter-county; (iii) competitive; and (iv) recreationally active. Chi-square and logistic regression analyses were used to explore differences between those at risk or not at risk of LEA. Results: Risk of LEA was identified in 40% (n?=?331) of 833 participants and was 1.7 and 1.8 times more likely in international and provincial/inter-county athletes compared to those who were recreationally active (International: odds ratios (OR) 1.68, 95% confidence intervals (95%CI) 1.12–2.54; Provincial/inter-county: OR 1.83, 95%CI 1.20–2.77). In participants at risk of LEA, missing >22 days of training during the previous year due to illness occurred 3 times more frequently (OR 3.01, 95%CI 1.81–5.02). Conclusion: Risk of LEA was widespread in this heterogeneous sample. Awareness of LEA and the development of appropriate energy management strategies to ensure athlete health across levels of competition are required.  相似文献   
52.
摘要:心血管疾病(CVD)一直是全世界最主要的死因。由于CVD等慢性疾病对健康的威胁越来越大,有必要开展生活方式干预项目以控制这些疾病的危险因素。本研究的目的是评估美国的重要慢病干预项目—HELPS治疗型生活方式改变(TLC)项目对减少CVD危险因素和其他慢性疾病的有效性。方法:140位大学教职工参加为期12周的HELPS TLC项目,干预前后用配对t检验对其体重、BMI、腰围(WC)、6分钟步行距离(6MWD)、空腹血脂和血糖进行测定和比较。结果:干预后6MWD显著增加,总胆固醇(TC)和WC显著下降。对“高危”参与者进一步分析显示:BMI(-1.5±0.5,-3.9%)、TC(- 22.8±4.0,-9.0%)、LDL(- 14.1±4.9,9.3%)和血糖(-6.9±2.2,-6.1%)均显著下降;男性腰围(-4.5±0.8,-10%)显著减小,女性未见显著改变(-1.5±0.5,-4.0%)。此外,体重的变化与TC(r=0.43)、LDL(r=0.35)和血糖(r=0.44)的变化均显著相关。结论:参加12周的生活方式干预项目可以使CVD危险因素减少,特别是在CVD“高危”个体中。HELPS TLC项目的远期效果还待进一步深入研究。  相似文献   
53.
一个句子的焦点是句子语义的重心所在。疑问词是疑问句的语义重心,因而疑问句的焦点就是疑问词。本文以焦点和突显观为理论依据,考察了英汉多个疑问词在特指问句中的句法位置,揭示出在特指问句中英语多个wh-词移位和汉语多个疑问词原位的原因。英语特指问句中多个wh-词必须有一个移至句首,这是其自身显性的焦点性和突显性的结果。  相似文献   
54.
The present paper aims at proposing a structured methodology to evaluate the results of an academic training course addressed to postgraduate students. The evaluation process intends to identify the efficacy of an education course by means of a comparison between the general objectives and the results expected by the students. Since the evaluated aspects by the students, detected by means of questionnaires, are both quantitative and qualitative, the proposed methodology is based on the analytic hierarchy process (AHP). In order to facilitate the evaluation process, answers have been modelled by means of linguistic variables. In particular, different evaluation scales have been used and each one is characterized by different levels associated to different fuzzy numbers.  相似文献   
55.
Desire under the Elms reveals a tragedy of spiritual and survival desire of human being. O’Neill creates many Bible ar-chetypes in Desire under the Elms. The thesis analyzes and appreciates Desire unde...  相似文献   
56.
针对一个占主导地位的零售商和两个制造商(名牌产品和普通产品制造商)组成的二级供应链,考虑制造商之间的定价顺序和低碳偏好消费者对普通产品的接受度,分别构建普通产品制造商采用或不采用减排技术情景下的收益模型,得出各情景下最优零售价格和收益。研究发现:零售商选择销售哪种产品与顾客对普通产品的接受度有关;普通产品制造商的减排策略主要取决于减排成本。在相同减排策略下,若顾客对普通产品接受度较大,制造商同时定价时产品的最优零售价小于等于不同时定价时产品的最优零售价,而同时定价时制造商的最优收益大于等于不同时定价时的最优收益,因此两个制造商应同时定价以获得更大的收益。  相似文献   
57.
We write as critical theorists, who consider that in terms of scoping out robust conceptual elaborations which are suitable for contemporary schooling, that physical education has ground to make up connecting theory with practice and practice with theory. We advocate that aspects of existentialism and phenomenology can provide a theoretically sound basis on which to argue that embodied learning should be the foundational cornerstone of physical education programmes. To avoid embodied learning becoming overly learner centric and insular, we advance Merleau-Pontian informed ideas on how learning could flourish when an individual and embodied focus merges with a school-wide physical culture agenda which is underpinned by social and moral theorizing. In developing our focus on merging embodied learning and physical culture, we draw upon MacIntyrean views on the goods which are internal to practice and extend thinking on how these goods could merge with the diverse aims and intentions informing the culture and ethos in schools. In pursuing these ambitions, we outline the constructive activist-based benefits of teachers working within subsidiarity-based school communities where pedagogical decisions are made at a level consistent with realizing whole schools aims. This is in spite of our acknowledgement that the lack of career-long professional learning adds to the difficulty of achieving these aims. In conclusion we argue that if physical education is to become a pivotal component of realizing a diverse range of whole school aims there is a need for greater professional engagement with pedagogical approaches that attempt to derive greater meaning from learners movement experiences and which help learners to understand better both their own identity and the ethos of the school context and environment they share with others.  相似文献   
58.
为保障客滚船航行安全,在分析客滚船航行安全影响因素的基础上,构建客滚船航行安全因果关系图,并运用Vensim-DSS构建客滚船航行安全仿真模型.对渤海上的某一客滚船的航行安全进行仿真,分析安全投入增加对客滚船航行安全水平的影响,得出结论:客滚船航行安全系统是一个复杂的动态系统,其航行风险主要是由人、货物、自然环境、交通环境、硬件设施和管理等6个因素交叉耦合导致的,其中人、货物和自然环境对客滚船的航行安全水平影响显著.这可为客滚船航行安全风险管理及防控方面的研究提供参考.  相似文献   
59.
摘要:为科学预测和控制学校体育场地设施对社会开放的安全风险,运用文献资料法、访谈法、案例分析法、问卷调查法和数理统计法对学校体育场地设施对社会开放过程中出现的安全风险因素进行研究。基于90个开放案例的事故树分析,识别出开放过程中的物、人、制度和环境4大类,共30个安全风险因素;通过巴雷托分析法和风险矩阵分析法评估出运动场地、运动器材设施,锻炼者、管理者4类关键安全风险因素11个;针对关键安全风险因素,提出引入第三方管理,分时、分类、分阶段开放,与社区合作、加强社区居民的管理,多元主体协同供给体育指导、咨询服务等事前风险预防措施;引入开放风险保险制度,设立开放风险专项基金制度的事后风险转移措施。以期能解决学校体育场地设施对社会开放过程中面临的实际问题,推进学校体育场地设施资源共享,促进全民健身事业的发展。  相似文献   
60.
城市土地资源的稀缺性使得成熟地段的新房交易数量急剧减少,二手房的交易量稳步攀升,二手房贷款逐渐升温。但我国二手房贷款市场存在的问题还很多,深入地分析和探索这些问题,寻找解决的办法和对策,对于稳定二手房交易有着十分重要的意义。  相似文献   
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