本期评介

如果说我太重理论……那你就是太重实践.大卫·里卡多致托马斯·毛瑟斯的一封信本期的主题是讨论发明的某些社会文化意义.发明是人的创造,与揭开自然奥秘的发现不同.发明的社会文化意义多种多样.如果发明确实适应需求,那么它就应当具有提供廉价的或至少是买得起的资源的经济功能;如果它能使用户节省时间,那么就是文化上的一项有益之举,因为它可以解放用户的脑和手,如果它能增强或取代人的天赋能力,那就相当于延长了人的工作寿命.     

西方世界教育改革的趋向——当前的争论

这篇文章企图向广大读者介绍现代盛行于西方世界高度工业化的商品经济国家里教育改革和教育更广阔地发展的主要特点和观点。此文以六十年代丰富的教育遗产为背景,并且考查了社会、经济、历史和政治上的因素,这些因素在它们特有的民族文化的体系中,对各自教育体系的发展具有传统的影响。但是现在比过去突出地提出一个统一的教育结构,这种发展意味深长地超越了国家的界线。     

V.克列依尔的三级跳远训练

V.克列依尔是苏联三级跳远的国家教练,也是萨涅耶夫的教练,他论述了三级跳运的选才,技术和训练问题。     

精选的糖类饮料对长时间自行车运动能力及糖元利用的影响

试验以8名受过良好训练的男性自行车运动员为对象。研究目的在于确定摄取糖类物质对运动能力及肌糖元利用的影响。每次试验前二天,受许者以70％的最大吸氧量为强度,进行60分钟的“排空蹬骑”。随后摄取高糖膳食(500克/天)。在正式实验中,受试者进行2     

Long-term trends in home advantage in professional team sports in North America and England (1876-2003)

Home advantage is quantitatively defined and calculated for each season since the start of the main professional sports in North America and England. Over 400,000 games are analysed. The leagues represented are the National League (1876-2002) and American League (1901-2002) for baseball, the National Hockey League (1917-2003) for ice hockey, the National Football League (1933-2002) for American football, the National Basketball Association (1946-2003) for basketball, and the four levels of professional football, formerly called the Football League, in England (1888-2003). Problems caused by unbalanced playing schedules are considered. The results are presented graphically to show long-term trends and sudden changes. The highest levels of home advantage for all sports were in their early years of existence. Home advantage in ice hockey, basketball and football in England has declined over the last two decades. In baseball there has been very little change over the last 100 years, with home advantage consistently lower than in other sports. There was a large drop in home advantage in football in England following the 7-year suspension of the league during the Second World War. The trends and changes provide some evidence that travel and familiarity contribute to home advantage, but little in support of crowd effects.     

Isokinetic knee extension and vertical jumping: are they related?

The aim of this study was to examine joint power generation during a concentric knee extension isokinetic test and a squat vertical jump. The isokinetic test joint power was calculated using four different methods. Five participants performed concentric knee extensions at 0.52, 1.57, 3.14 and 5.23 rad x s(-1) on a Lido isokinetic dynamometer. The squat vertical jump was performed on a Kistler force plate. Kinematic data from both tests were collected and analysed using an ELITE optoelectronic system. An inverse dynamics model was applied to measure knee joint moment in the vertical jump. Knee angular position data from the kinematic analysis in the isokinetic test were used to derive the actual knee angular velocity and acceleration, which, in turn, was used to correct the dynamometer moment for inertial effects. Power was measured as the product of angular velocity and moment at the knee joint in both tests. Significant differences (P < 0.05) were found between mean (+/- s) peak knee joint power in the two tests (squat vertical jump: 2255 +/- 434 W; isokinetic knee extension: 771 +/- 81 W). Correlation analysis revealed that there is no relationship between the peak knee joint power during the vertical jump and the slow velocity isokinetic tests. Higher isokinetic velocity tests show better relationships with the vertical jump but only if the correct method for joint power calculation is used in the isokinetic test. These findings suggest that there are important differences in muscle activation and knee joint power development that must be taken into consideration when isokinetic tests are used to predict jumping performance.     

Stress in elite sport performers: a comparative study of competitive and organizational stressors

The purpose of this study was to compare the content and quantity of competitive and organizational stressors in elite athletes. Ten international performers were interviewed about sources of stress. Content analysis of the data involved categorizing the demands associated primarily and directly with competitive performance (#CS = 21) under the post hoc dimension "performance issues", and the demands associated primarily and directly with the sport organization (#OS = 72) under one of the following four post hoc dimensions: "environmental issues", "personal issues", "leadership issues" and "team issues". Frequency analysis revealed that the participants mentioned the competitive stressors (sigma = 95) less than the organizational stressors (sigma = 215). Further analysis within these categories showed that the mean number of participants citing individual competitive stressors (M = 4.52) was greater than the mean number of participants citing individual organizational stressors (M = 2.99). The findings indicate that elite athletes experience and recall more demands associated primarily and directly with the sport organization than with competitive performance. Furthermore, this population appears more likely to mention similar competitive stressors but varied organizational stressors, probably because the former are inherent and endemic to elite sport, whereas the latter are essentially extraneous and widely distributed.