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The purpose of this study was to examine if steps/day taken by middle school students varied based on aerobic fitness classification. Middle school students (N = 223; 112 girls, 111 boys) were assigned to three aerobic fitness categories (HIGH, MOD, LOW) based on results of the FlTNESSGRAM PACER test. Four weekdays of pedometer monitoring determined activity levels (steps/day). Boys accumulated significantly more steps/day than girls, 11,589 +/- 3,270 and 10,232 +/- 2,517 steps/day, respectively; F(1,219) = 16.0, p < .001, eta2 = .055. There were no differences in steps/day between grades. HIGH fit participants accumulated significantly more steps/day, F(2, 217) = 12.2, p < .101, eta2 = .101, than moderately fit and low fit participants (approximately 1,491 and ; 2,867 steps/day, respectively). Middle school students who participated in sports in addition to physical education (PE) accumulated significantly more steps/day (approximately 980 steps/day) than those participating in PE only, F(1, 219) = 10.0, p < .01, eta2 = .044. Although the relationship between physical activity and aerobic fitness was moderate (0.35; p < .01), these data demonstrated significant differences in accumulated steps/day among youth of varying aerobic fitness levels. Whether improved fitness levels were the result of additional activity or the cause of it remains to be determined. Regardless, the fittest middle school students were also the most active and accumulated a significant amount of steps/day through organized extracurricular physical activities.  相似文献   
44.
介绍了如何将 MARC格式的文件 ,转换成数据库文件格式 ,最后形成 Excel格式的文件 ,在网上进行信息发布  相似文献   
45.
参加IPTC北京年会的法新社多媒体实验室主任、资深媒体技术、新闻技术标准专家Laurent Le Meur先生4月3日在新华社的技术研讨会上,首先介绍了法新社的新闻业务和技术概况,他说:法新社每天播发及时、精确、深度报道,每天有遍及世界165个国家的2900名员工为其工作,每天播发视频、图片、图表和多媒体稿件,法新社每天发布的多媒体稿件达350~600篇左右,每天播发的各类新闻大多遵循了NewsML标准。  相似文献   
46.
We propose a new method, based on inertial sensors, to automatically measure at high frequency the durations of the main phases of ski jumping (i.e. take-off release, take-off, and early flight). The kinematics of the ski jumping movement were recorded by four inertial sensors, attached to the thigh and shank of junior athletes, for 40 jumps performed during indoor conditions and 36 jumps in field conditions. An algorithm was designed to detect temporal events from the recorded signals and to estimate the duration of each phase. These durations were evaluated against a reference camera-based motion capture system and by trainers conducting video observations. The precision for the take-off release and take-off durations (indoor < 39 ms, outdoor = 27 ms) can be considered technically valid for performance assessment. The errors for early flight duration (indoor = 22 ms, outdoor = 119 ms) were comparable to the trainers' variability and should be interpreted with caution. No significant changes in the error were noted between indoor and outdoor conditions, and individual jumping technique did not influence the error of take-off release and take-off. Therefore, the proposed system can provide valuable information for performance evaluation of ski jumpers during training sessions.  相似文献   
47.
中国体育在世界格局中明确了第一集团的位置,但是优势项目不多,并且很难获得更大突破,在国内优势项目与区域发展也存在不均衡的表现。探讨了近些年中国体育在世界取得的成绩情况,分析了实力变化情况,以期促进我国竞技体育的可持续发展。  相似文献   
48.
Abstract

The aims of this study were twofold: (1) to characterize repeated high-intensity movement activity profiles of a professional soccer team in official match-play; and (2) to inform and verify the construct validity of tests commonly used to determine repeated-sprint ability in soccer by investigating the relationship between the results from a test of repeated-sprint ability and repeated high-intensity performance in competition. High-intensity running performance (movement at velocities >19.8 km · h?1 for a minimum of 1 s duration) was measured in 20 players using computerized time–motion analysis. Performance in 80 French League 1 matches was analysed. In addition, 12 of the 20 players performed a repeated-sprint test on a non-motorized treadmill consisting of six consecutive 6 s sprints separated by 20 s passive recovery intervals. In all players, most consecutive high-intensity actions in competition were performed after recovery durations ≥61 s, recovery activity separating these efforts was generally active in nature with the major part of this spent walking, and players performed 1.1 ± 1.1 repeated high-intensity bouts (a minimum of three consecutive high-intensity bouts with a mean recovery time ≤20 s separating efforts) per game. Players reporting lowest performance decrements in the repeated-sprint ability test performed more high-intensity actions interspersed by short recovery times (≤20 s, P < 0.01 and ≤30 s, P < 0.05) compared with those with higher decrements. Across positional roles, central-midfielders performed more high-intensity actions separated by short recovery times (≤20 s) and spent a larger proportion of time running at higher intensities during recovery periods, while fullbacks performed the most repeated high-intensity bouts (statistical differences across positional roles from P < 0.05 to P < 0.001). These findings have implications for repeated high-intensity testing and physical conditioning regimens.  相似文献   
49.
To explore the citation evolution of papers published in the same year but different month, we selected papers from a discipline (physical geography), a subject (diabetes: endocrine and metabolism) and a journal (Journal of Biological Chemistry) published in 2005 as research objects. These papers were divided into six groups according to the difference in publication month, and we analyzed citations to these papers for the 9 years after publication. The results showed that within 5 years after papers from physical geography were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); after that, the differences were not statistically significant. Within 5 years after papers from diabetes (endocrine and metabolism) were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Within 7 years after papers from the Journal of Biological Chemistry were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Citations of papers followed the same pattern irrespective of discipline, subject or journal: citations of papers published in the same year but different month were obviously different in the first few publishing years, but as time went on, only the difference in publication month in a calendar year did not affect the papers' longer‐term citation.  相似文献   
50.
文章针对电子政务中因政务监管报告信息格式不同、信息内涵不同导致的信息孤岛问题,研究了目前在国内外报告领域兴起的XBRL语言以及国内外政府中XBRL应用的情况,指出XBRL在电子政务领域的应用能促进电子政务的信息互通,并提出XBRL在电子政务领域三个级别的应用模式,论述了XBRL技术在电子政务领域的优势和影响,指出影响XBRL应用推广的因素并提出实施建议.  相似文献   
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