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981.
《European Journal of Sport Science》2013,13(3):183-190
Abstract In this study, we investigated the effect of 1- and 3-week tapering periods on concentrations of plasma testosterone (T), cortisol (C), T/C ratio, mood state, and performance in elite male cyclists. After 8 weeks of progressive training, cyclists were randomly assigned to a control group (n=12) who continued performing intense training for a further 3 weeks, or a taper group (n=12) who continued with a 50% reduction in training volume. Blood testosterone and cortisol concentrations were assayed and the T/C ratio calculated from analysis obtained via standard ELISA. Mood state was determined using the Profile of Mood States (POMS) questionnaire. All data were collected immediately after a 40-km time-trial performed before, during, and after the 8-week training protocol and after the 1- and 3-week tapering/training periods. In the taper group, 40-km time-trial time decreased significantly (P<0.01) and equally for both the 1- and 3-week taper periods relative to the control group. There were significant elevations in T/C ratio (P<0.001) and reductions in cortisol concentrations and POMS scores in the taper group relative to the control groups at the end of both the 1- and 3-week tapering periods. Hence, taper periods are effective in improving performance and mood state and elevating the blood T/C ratio. 相似文献
982.
针对目前市政设计院价格信息整理和共享情况的不足,提出并开发了一套基于B/S模式的市政设备材料价格数据库。着重介绍了基于B/S模式的市政设备材料价格数据库的设计、开发过程及实现系统的关键技术。 相似文献
983.
独立学院勤工助学管理系统设计 总被引:1,自引:0,他引:1
勤工助学管理信息化是教育信息化改革的工作之一。介绍了基于c/s模式的独立学院勤工助学信息管理系统的设计与实现方案。 相似文献
984.
当前在砂砾含水层的成井工艺中,均采用常规程序。即在所设计的砂砾含水层部位,配置相应的滤管,滤管外仍采用缠丝,再包扎尼龙滤网。管外投填滤砂。用活塞提拉或空压抽水洗井。此为传统工艺。由于受传统工艺束缚,缺乏对砂砾含水层结构的具体分析。施工工艺的针对性、对策性欠妥。多数成井井阻大,产水效率低。笔者在施工中,改变传统理念。提出反冲淘砂法成井。取得极为理想的效果,且施工工艺简单,井阻系数小,绝大部分为超完善井,产水效果佳。可视作砂砾含水层成井之新工艺。 相似文献
985.
简单介绍RS-232、RS-422串行接口的传输方式、通讯距离、抗干扰能力、传输速率等技术性能特点,以及专为工业环境设计的多用户MOXA CP-114串行接口的通信卡,在电视自动播出上的应用。快捷、安全、可靠、稳定地将RS-232通信接口转换为RS-422/485通信接口,以提高视频服务器的工作稳定性,确保电视节目的安全播出。 相似文献
986.
介绍了一种基于TMS320DM368处理器的网络视频监控系统的实现方案,该系统支持扩展多种视频采集前端接口,支持包括以太网、3G网络和WIFI的多种通信方式。基于RTP/RTSP框架设计了多线程流媒体服务器,并在Web服务器端设计了动态页面,使用CGI技术实现了用户与服务器的交互。测试结果显示系统在低带宽和复杂网络条件下仍能获得很好的监控画面效果,实时性和稳定性好。 相似文献
987.
采用基于C#.net 三层框架和ADO.NET访问技术,设计了基于C/S(Client/Server)模式的银企对账系统,并详细阐述系统的架构、功能划分、数据库设计及系统实现过程中所涉及的关键技术。设计的系统有利于企业的财务管理,提高了企业对账效率。 相似文献
988.
BD-2/GPS组合导航系统选星算法及定位分析 总被引:1,自引:0,他引:1
为解决组合导航系统定位精度与快速定位之间的矛盾,提出一种新的选星算法.该方法将可见卫星仰角与遗传算法相结合,以几何精度因子(GDOP)计算模型作为遗传算法中判断解优劣的适应度函数,从而达到快速定位的效果.将应用该方法所得的GDOP和算法运行时间与应用最佳GDOP算法计算所得的相应结果进行对比,发现采用该方法得到的GDOP接近最优值,而且选星算法计算时间减少.实验数据分析证明该方法在实时性和可行性方面的优越性. 相似文献
989.
Katrien De Cocker Greet Cardon Ilse De Bourdeaudhuij 《Research quarterly for exercise and sport》2013,84(5):429-437
Pedometer-determined physical activity (PA) levels in Belgian adults were provided and compared to PA scores reported in the International Physical Activity Questionnaire (IPAQ). The representative sample (N = 1,239) of the Belgian population took on average 9,655 (4,526) steps/day. According to pedometer indices 58.4% were insufficiently active. Steps/day differed significantly between gender (F = 5.0, p = .026), age groups (F = 3.3, p = .01), employment status (F = 6.2, p = .013), and days of monitoring (F = 7.4, p = .007). Steps/day were negatively correlated to the time spent sitting and positively to PA at work, in transport, and in leisure time (p < .001). Steps data can discriminate between PA levels reported in the IPAQ. Belgian population pedometer-determined PA levels are higher than those reported in samples of the United States; however, there is a wide distribution of ambulatory behavior. 相似文献
990.
Abstract The purpose of this study was to examine knee extensor/flexor muscle strength and physical activity in healthy males and females approaching retirement. Peak torques of the knee extensor and knee flexor muscle groups were measured bilaterally in 95 individuals (mean age 59.4 years) using an isokinetic dynamometer. Isokinetic concentric contractions were performed at angular velocities of 1.05 and 3.14 rad · s?1. Physical activity, including household, leisure, and sporting activities, was assessed. The results show that the average peak torques exhibited were lower than previously reported in studies using the same methodology with different populations of similar age and body size. Over one-third of the participants were sedentary, with just 13% being active enough to obtain health benefits. The poor muscle strength and low physical activity of this self selecting group of healthy working adults were surprising, and potentially a cause for concern. The combination of retirement being a potential watershed for a decrease in physical activity and the known age-related decline in physical performance indicates that some of these participants are at risk of losing their functional independence fairly early in the retirement stage. We recommend the introduction of effective health promotion interventions for individuals approaching retirement, encouraging them to become more physically active. 相似文献