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141.
Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.  相似文献   
142.
143.
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   
144.
Abstract

In this paper we report on two studies that investigated the physical demands of professional rugby league match-play. Instudy one, National Rugby League (NRL) and National Youth Competition (NYC) players underwent global positioning system (GPS) analysis during competitive matches. No differences (P > 0.05) were observed between playing standards for minutes played, total distance covered, or the distances covered at low and high speeds. However, NRL players engaged in significantly more repeated high-intensity effort bouts than NYC players (13.1 ± 0.8 bouts vs. 9.7 ± 1.1 bouts). Reductions in physical performance occurred from the first to second half for both NRL and NYC players. In study two, we investigated, in the same players, the physical demands of professional rugby league match-play when players were competing in trial and regular fixture matches. The locomotor demands of trial matches were lower than fixture matches, with players covering less distance per minute of match-play, including less distance at low and high speeds. Players were also less likely to engage in repeated high-intensity effort bouts in trial matches than fixtures. These findings demonstrate that neither NYC matches nor NRL trial matches adequately reflect the intense physical demands of NRL fixture matches.  相似文献   
145.
ABSTRACT

The aim of this study was to systematically review the literature to verify the association between participation in sports (PS) in childhood and adolescence and physical activity (PA) in adulthood. A systematic search was conducted in the following databases: Medline (PUBMED), Web of Science, Scopus, and SPORTDiscus, LILACS and SciELO. All steps of the process followed the recommendations of the PRISMA FlowDiagram. After all the steps of the process, 29 articles were included for analysis. In general, only three of the studies analyzed found no relation between PS in childhood and adolescence and PA in adulthood. However, a positive relationship was found to be weak in only 7% of the studies, a moderate relation in 62% of the studies, and a strong relation in 21%. It was found that higher weekly frequencies of PS; persistence of at least three years of PS and, finally, the highest level of practice and/or competition reached were related to higher levels of PA in adulthood. Thus, it can be concluded that there is a positive association considered moderate to strong between PS in childhood and adolescence and PA in adulthood.  相似文献   
146.
Abstract

Two groups of 23 junior high school boys were tested before and after an eight weeks' progressive resistance training program. The experimental group participated in this program, but the control group took part only in regularly scheduled physical education classes. At the end of the eight weeks, it was found that the experimental group increased their ability to do pull-ups, push-ups, the Harvard Step Test, Dodge run, the Burpee test, and trunk extension and flexion. The control group improved in the Dodge run, the Burpee test, push-ups, and trunk extension. In no case did the improvement of the control group exceed the improvement of the experimental group. The experimental group also increased in anthropometric measurements. Medical examinations indicated that no harmful effects were experienced by either group.  相似文献   
147.
运用摄影测量法和Novel Pedar-X足底压力测试系统采集了16名太极拳练习者在太极拳运动和正常步行中足底压力和运动影像信息,并对两种运动方式的单脚支撑姿势持续时间指标进行对比分析。研究表明:与正常步行相比,在太极拳运动中单脚支撑姿势总的持续时间所占比例(标准化值)较少(P<0.05);单次单脚支撑姿势平均持续时间较长(P<0.01);认为太极拳运动可以提高人体单脚平衡能力。另外还发现太极拳运动和正常步行中地面反作用力都在不断变化;太极拳运动中地面反作用力小于其正常步行值。  相似文献   
148.
ABSTRACT

Purpose: This study aimed (1) to compare physical activity (PA) indicators, metabolic biomarkers, and comorbidity, (2) to investigate the relationship between PA indicators and metabolic biomarkers, comorbidity and (3) to identify barriers to PA in patients with type 2 diabetes (T2DM) who are using oral hypoglycaemic agent (OHA) or combined OHA and insulin (OHAiN). Methods: Sixty-one patients were classified as patients using only OHA or combined OHAiN. Metabolic biomarkers (waist-to-hip ratio, body mass index (BMI), lipid profile, glycosylated haemoglobin (HbA1c), fasting blood glucose, comorbidity and PA indicators (self-reported PA, number of steps (NOS), 6-minute walking distance (6MWD)) were assessed. PA perceptions and reasons for inactivity were questioned. Results: The comorbidity (p = .013), low-density lipoprotein-cholesterol (p = .026), total cholesterol (p = .008) and HbA1c (p = .020) were higher and PA level was lower (p = .007) in the OHAiN group. NOS was positively correlated with high-density lipoprotein-cholesterol (p = .037) and negatively correlated with BMI (p = .007). 6MWD was negatively correlated with BMI (p = .014) and comorbidity (p = .004) in the OHA group. BMI was a significant predictor of NOS (adjusted R2 = 0.242) and comorbidity for 6MWD (adjusted R2 = 0.250) in the OHA group. The majority of the patients (OHA = 34.3%, OHAiN = 42.3%) reported “lack of time” as the most common barrier to PA. Conclusions: This study showed that patients on OHAiN have lower PA levels, poorer metabolic profiles, and higher comorbidity rates than OHA users. PA indicators were related with some metabolic biomarkers and comorbidity in only OHA users. The most common reason for inactivity was “the lack of time” in both groups.  相似文献   
149.
采用文献资料、问卷调查、访谈及实地考查以及数据统计等方法分析青海省农牧区城镇居民体育活动的特征,包括体育人口特征、体育消费特征、宣传和组织管理特征、社会体育指导员的培训利用特征以及群众体育资源特征。在分析基础上提出农牧区城镇居民体育活动的建议。  相似文献   
150.
通过问卷调查的形式,采用统计、计量分析方法,深入分析影响大学生运动行为的社会经济因素及社会心理因素之间的定量关系。结果显示,52%的学生表示自己有运动习惯,但是真正符合美国运动医学会(ACSM)推荐的规律运动标准的仅34.2%;其中男生有规律运动者占21.5%,女生仅为12.7%;低年级规律运动的比例高于高年级。通过logistic回归可以预测全体受访者是否规律运动的因素包括:性别、年级、体育测试压力、母亲受教育的程度和可利用的时间是否充足。研究提示,大学生规律运动比例较低,社会经济状况和社会心理因素会对其规律运动行为造成影响,因此针对影响规律运动的因素制定其相应的对策尤为重要。  相似文献   
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