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31.
停止课外训练对小学女生最大心率的影响 总被引:1,自引:0,他引:1
以探讨小学生最大心率水平和停止课外训练对小学生最大心率的影响为目的。采取的方法是在跑台上运用Bruce法对停训8周前后的8名小学女生最大心率进行比较,并运用文献资料法,对比国内外学者在停训前后最大心率的研究。结果表明,小学女生停训前后的最大心率、运动能力均无显著差异;用传统的220-年龄推算最大心率可能不准确。 相似文献
32.
李琴兰 《天水师范学院学报》2002,22(5):50-50
从国内外的情况看,开发智能化电器已成为当前低压电器行业的重点方向,断路器是低压电器智能化的突破口。 相似文献
33.
于佳祥 《哈尔滨体育学院学报》2002,20(3):56-57
对篮球比赛罚球过程中运动员的心理特征进行了简要分析,并提出了临场心理状态的调试方法和训练方法,供同仁研究参考。 相似文献
34.
赛艇运动员稳态心率的研究 总被引:3,自引:0,他引:3
探讨了赛艇运动员在赛艇测功仪上作中等强度匀速运动时的稳态心率。 相似文献
35.
远距离单手肩上投篮训练方法探讨 总被引:1,自引:0,他引:1
讨论影响投篮命中率有7个因素:手法、瞄准的方向、球的旋转、抛物线、协调性、判断反应和心理因素,并提出提高远距离投篮命中率的训练方法. 相似文献
36.
Christina Heady Megan M. Morrison Joshua Vossler 《The Journal of Academic Librarianship》2018,44(5):642-649
The purpose of this ecological study was to examine the impact of a library credit course on graduation rates and GPA using pre-existing records. Over 20?years of aggregate institutional data were analyzed to evaluate the course's impact on first-time-full-time, white, and black students. Results were mixed: students who took the course were less likely to graduate than their peers who did not take the course but enjoyed slightly higher GPAs at graduation. It was discovered that students taking the course are not representative of the overall student body and struggle academically. Implications for revisions to the library credit course are discussed. 相似文献
37.
通过对透析法、酸析法和冰冻法提取丝胶效果的比较,得出冰冻法是提取丝胶的较好的方法,其最佳的提取条件是:pH=4,-20℃,冰冻时间为13 h,丝胶液浓度为32.8%。 相似文献
38.
Danielle M. Logue Sharon M. Madigan Mirjam Heinen Sarah-Jane McDonnell Eamonn Delahunt Clare A. Corish 《European Journal of Sport Science》2019,19(1):112-122
ABSTRACTIntroduction: 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
39.
The high prevalence of child sexual abuse (CSA) is concerning, particularly as survivors are at increased risk for multiple adverse outcomes, including poor mental health across the lifespan. Children born at an extremely low birth weight (ELBW; <1000 g) and who experience CSA may be a group that is especially vulnerable to psychopathology later in life. However, no research has considered the mental health risks associated with being born at ELBW and experiencing CSA. In this study, we investigated the mental health of 179 ELBW survivors and 145 matched normal birth weight (NBW; >2500 g) participants at ages 22–26 and 29–36. At age 22–26, CSA was associated with increased odds of clinically significant internalizing (OR = 7.32, 95% CI: 2.31–23.23) and externalizing (OR = 4.65, 95% CI: 1.11–19.51) problems among ELBW participants exposed to CSA compared to those who did not, though confidence intervals were wide. At age 29–36, CSA was linked to increased odds of any current (OR = 3.43, 95% CI: 1.08–10.87) and lifetime (OR = 7.09, 95% CI: 2.00–25.03) non-substance use psychiatric disorders, however, this did not hold after adjustment for covariates. Statistically significant differences in mental health outcomes were not observed in NBW participants exposed to CSA compared to NBW participants who were not exposed. Survivors of significant perinatal adversity who are also exposed to CSA may be at higher risk for psychopathology through the fourth decade of life. 相似文献
40.
大尺寸薄壁钢筋混凝土结构,对温度的变化和基础的不均匀沉降较为敏感。制定合理的施工方案,材料的合理选择、施工流程精心组织保证了裂缝控制效果良好。 相似文献