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961.
以优秀女子赛艇W8+运动员为研究对象,探讨优秀女子公开级赛艇运动员在赛前训练和赛后停训及恢复训练阶段体成分和AT4功率的变化情况和相关性特点。结果:瘦体重和骨骼肌质量在赛前训练和赛后停训阶段呈显著下降,恢复训练5周后较赛前训练后期显著升高,但仍显著低于赛前训练初期水平;体脂%在赛前训练和停训及恢复训练阶段均呈连续显著升高趋势;AT4功率在赛前和恢复训练6周后变化不显著,仅与体脂%呈中度负相关(P〈0.01)。结论:AT4功率和体成分各指标在赛前训练和停训阶段易出现不良变化,且较难改善,较高的体脂%可能是限制运动水平提高的重要因素之一。  相似文献   
962.
“生动植物资源不仅具有直接的经济价值,其丰富的基因资源开发的潜力更是难以估量,已成为国际上争夺的焦点。建立濒危野生动植物基因资源库,通分子生物学手段对这些珍稀资源进行立体的保护是现在国际上通行的方法。天麻(Gastrodia elata Blume)作为一种名贵中药材,有着多种生物活性作用。本文从核心种质库的概念、天麻的化学成分和生物活性作用及天麻的遗传多样性几个方面分析了建立天麻核心种质库的重要性、必要性和可行性,为实现天麻基因资源的立体永久保存和利用提供参考。  相似文献   
963.
PurposeTo investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects.MethodsA total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated.ResultsPeak oxygen uptake was 37.6 ± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = −0.684, p < 0.0001; women: r = −0.681, p < 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass.ConclusionPeak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects.  相似文献   
964.
运用测验法对浙江省跆拳道队8名女队员进行体成分与体重测量,通过现场观察法和访谈法调查冬训及体重控制情况,认为冬训体能训练使队员脂肪含量明显减少和肌肉含量明显增加,大部分队员体重略有下降,针对训练和饮食提出建议。  相似文献   
965.
常君志 《科教文汇》2013,(17):167-167,169
在实施素质教育的今天,培养学生的自学能力非常重要。小学高年级的学生,已经具备修改作文的能力,教会学生修改作文的方法,培养学生修改作文的能力,会使学生的写作更上一层楼。  相似文献   
966.
韩岩岩  孟燕 《科教文汇》2013,(29):148-148
中庭空间作为现代酒店建筑普遍采取的空间形式,能够增强酒店气势、美化酒店自然风光、提高酒店的价值。本课题对酒店建筑的精华——“中庭空间”的营造进行研究。论文首先对中庭的概念和发展历程进行简要的介绍,随后通过对酒店消费群体的消费心理的感知调研后进行分析,最后归纳总结对酒店中庭空间景观设计的方法和原则。  相似文献   
967.
The subjects were 31 successful schoolboy rugby players and 25 successful schoolboy hurlers; 34 non‐team members acted as controls. Thirty‐one anthropometric measurements were taken on each subject: height, weight, sitting height, five skeletal lengths, six skeletal diameters, 13 muscle circumferences and four skinfolds. The non‐players were significantly smaller than both the rugby players and the hurlers in weight, biacromial diameter, bideltoid, neck, chest, flexed arm, upper and lower thigh and calf circumferences. The non‐players were significantly smaller than the rugby players in arm length, femur diameter and waist, hip and relaxed arm circumferences. The non‐players were significantly smaller than the hurlers in femur length, biiliac and ankle diameters. There were no statistically significant differences between the rugby players and hurlers. Discriminant analysis produced a function containing terms for height, weight, fat free weight, humerus diameter and neck, bideltoid, forearm and calf circumferences which correctly assigned 83 (92%) of the subjects to ‘player’ and ‘non‐player’ categories. When the function was applied to the 15 members of the rugby team of a different school, 14 were placed in the ‘player’ category and one subject was given a borderline classification. It is concluded that there were differences in physique between the team members and non‐members and that the techniques used in the study were effective in quantifying them.  相似文献   
968.
Abstract

Bioelectrical impedance spectroscopy (BIS) provides an affordable and practical assessment of fat-free mass (FFM). However, little information is available on the assessment of changes in fat-free mass in top-level athletes using BIS. The aim of this study was to examine the accuracy of BIS in tracking changes in fat-free mass of elite male judo athletes from a period of weight stability to just before competition, using the four-compartment model (4C model) as reference method. In total, 27 elite male judo athletes (age 22.2 ± 2.8 years) were evaluated. Measures of body volume assessed by air displacement plethysmography, bone mineral content by dual-energy X-ray absorptiometry, and total-body water assessed with deuterium dilution were used in a 4C model. Fat-free mass was also assessed by BIS (FFMBIS). Changes in FFMBIS were not significantly different from measured by the reference method (P = 0.000). Furthermore, the r 2 was 0.62 and the standard error of the estimate was 1.03 kg. The limits of agreement ranged from ?3.36 to 2.59 kg with no bias observed. These findings demonstrate the viability of BIS as a valid tool for tracking fat-free mass in elite male judo athletes. However, based on the wide limits of agreement observed, BIS is less valid at an individual level for tracking fat-free mass in these athletes.  相似文献   
969.
Abstract

The purpose of this preliminary investigation was to determine the relative role of the distal lower extremity tissue masses of varsity athletes in predicting distal lower extremity injury sustained during a competitive season. One hundred male and female varsity athletes (basketball, volleyball, soccer, cross country) completed a questionnaire on general health, physiological, and psychosocial variables, during each sport's respective training camp. A series of anthropometric measurements were used as inputs to distal lower extremity tissue mass prediction equations to calculate lean mass, fat mass, bone mineral content and wobbling mass (lean mass + fat mass) and tissue mass ratios. Athletes were monitored throughout their respective seasons and were instructed to report any distal lower extremity injuries to a certified athletic therapist who was responsible for assessing and confirming the reports. Logistic regression analyses were performed to determine which variables significantly predicted distal lower extremity injury. Mean leg fat mass:bone mass (OR = 1.6, CI = 1.0 – 2.5), and competition surface (rubber OR = 8.5, CI = 1.5 – 47.7; artificial turf OR = 4.0, CI = 0.77 – 22.9) were identified as significant predictors of injury. Overall, tibia bone injuries were significantly associated with the ratio of fat mass:bone mineral content and the surface on which the athletes compete.  相似文献   
970.
Abstract

The aim was to analyse the physical growth and body composition of rhythmic gymnastics athletes relative to their level of somatic maturation. This was a cross-sectional study of 136 athletes on 23 teams from Brazil. Mass, standing height and sitting height were measured. Fat-free and fat masses, body fat percentages and ages of the predicted peak height velocity (PHV) were calculated. The z scores for mass were negative during all ages according to both WHO and Brazilian references, and that for standing height were also negative for all ages according to WHO reference but only until 12 years old according to Brazilian reference. The mean age of the predicted PHV was 12.1 years. The mean mass, standing and sitting heights, body fat percentage, fat-free mass and fat mass increased significantly until 4 to 5 years after the age of the PHV. Menarche was reached in only 26% of these athletes and mean age was 13.2 years. The mass was below the national reference standards, and the standing height was below only for the international reference, but they also had late recovery of mass and standing height during puberty. In conclusion, these athletes had a potential to gain mass and standing height several years after PHV, indicating late maturation.  相似文献   
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