首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   126篇
  免费   1篇
教育   75篇
科学研究   10篇
体育   30篇
文化理论   1篇
信息传播   11篇
  2023年   2篇
  2022年   4篇
  2021年   2篇
  2020年   6篇
  2019年   8篇
  2018年   6篇
  2017年   13篇
  2016年   13篇
  2015年   5篇
  2014年   8篇
  2013年   22篇
  2012年   7篇
  2011年   5篇
  2010年   1篇
  2009年   3篇
  2008年   2篇
  2007年   3篇
  2006年   1篇
  2004年   1篇
  2003年   3篇
  2001年   2篇
  1995年   1篇
  1991年   1篇
  1988年   1篇
  1986年   2篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1976年   2篇
排序方式: 共有127条查询结果,搜索用时 15 毫秒
1.
2.
Objective: To analyze the possible dose-response association between components of sports participation (intensity, volume and previous engagement) and 4-year mortality rates among Brazilian adults.

Methods: 679 males and females (mean age among men = 66.7 ± 9.3 years old and mean age among women = 64.8 ± 8.9 years old) composed the study sample. Sports participation was assessed using Baecke’s questionnaire, which considers intensity, duration and previous engagement. Medical records were used to identify the cause of the death. Cox regression analysis was performed to determine the independent associations of exercise components and mortality.

Results: Participants that reported exercising at moderate-vigorous intensity (Moderate/vigorous: 4.1% versus None/light: 10.3% [p-value = 0.012]; HR = 0.42 [0.1 to 0.94)] and for more than four months (≥4 months: 5.3% versus <4 months: 10.2% [p-value = 0.038]; HR = 0.47 [0.24 to 0.94]) had lower mortality risk. The percentage of survival according to all-cause mortality was significantly higher for participants engaged in sports at moderate-vigorous intensity (p-value = 0.014), as well as for those engaged in sports for periods superior than four months (p-value = 0.036).

Conclusion: We found higher percentage of survival among adults engaged in sports at moderate-vigorous intensity and with at least four months of previous engagement.  相似文献   

3.
The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13–17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6–10 repetitions at 60–70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50–80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (< 0.01) and increase in fat-free mass (< 0.01), VO2peak (< 0.01), 1 RM for leg press (< 0.01) and bench press (< 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (< 0.05) and leptin (< 0.05), as well as in insulin resistance (< 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.  相似文献   
4.
This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e. dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s?1. The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases.  相似文献   
5.
Science & Education - The purpose of this study is to identify and analyze meanings that the term complexity assumes in Brazilian theses and dissertations in the field of environmental...  相似文献   
6.
Information use is defined as the application of acquired and transmitted information in the decision making of an organization at the strategic and tactical levels. The purpose of the research is to investigate how information use architecture impacts information load and usability at the operational level of manufacturing where machines, humans and the production processes are information users. A new approach to information load is introduced which takes all the characteristics of information use (tacit, mechanical, paper and digitized) and possibilities of users (machine, operator and process) into consideration. Information use nodes are conceptualized building blocks for information use architecture which impact information load and usability. The results suggest that information use load is sensitive to information encoding/decoding. A combination of the federated and integrated information use architectures tends to result in a low information use load and can become a strategic tool for waste reduction. How information usability relates to load varies depending on the usability characteristic in view. The major conclusion is that a holistic approach to information systems includes the consideration of information use architecture which is an important factor in the management of information load and usability at the operational level.  相似文献   
7.
8.
Abstract

Adventure education philosophers have argued that controlled exposure to challenge can enhance participants' psychological resilience. This study supports this claim, demonstrating significantly greater gains in psychological resilience for 41 young adults participating in 22-day Outward Bound programs than in a control group. All Outward Bound participants reported positive changes in their resilience and their overall change effect size was large. Perceived levels of social support predicted 24% of the variance in resilience gain scores, with participants' ratings of the least supportive group member being the best predictor. The findings for enhanced resilience and the important role of social support warrant wider investigation. In promoting psychological resilience adventure educators are alerted to the importance of facilitating positive interpersonal relations and minimising the detrimental impact of the diverse needs of group members.  相似文献   
9.
10.
Trajectories of adjustment were examined in a sample of street-involved youth across a 1-year period. Participants (N = 113; Mage = 14.18 years; 80.5% male, 91% non-White) were recruited in three Brazilian cities. Interviews conducted at three time points included six measures of physical and psychological adjustment. Unconditional growth models revealed linear declines over time (i.e., improved adjustment) on three indicators: health symptoms, sexual risk behaviors, and negative affect. There were no linear changes in drug use, positive affect, or life satisfaction. Conditional growth models revealed few significant effects for age or gender, but ratings of stressful life events moderated longitudinal changes in health symptoms, drug use, and negative affect. Implications for practice, policy, and theory are discussed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号