第25届奥运会女子高低杠规定动作主要难度的运动学分析

本文利用计算机解析系统,对第25届奥运会女子高低杠规定动作中的主要难度动作的参数进行了运动学定量分析。解析结果表明,由面对低杠的高杠倒立开始的大摆动作,屈髋(腿加速)开始于过杠垂面之前,这与传统的摆动动作技术原理相悖。     

Cerebral activity prior to motion task performance: an electroencephalographic study

Cerebral activity, as reflected by power in the alpha waveband (8-13 Hz), was examined prior to the performance of three tasks with different effort and accuracy requirements. The study aimed to further investigate changes in activity observed in an earlier study in which expert karate performers exhibited significant increases in alpha band power during preparation for a training task. In contrast to the earlier research, the high effort task produced a significant decrease in 'alpha' power prior to performance. 'Alpha' power prior to the high accuracy task showed significant differences mediated by the outcome. Successful performance was preceded by higher levels of 'alpha' power than unsuccessful attempts. The reported use of a cognitive strategy on the first task produced a significant difference in activity, lower alpha power being associated with the use of such a technique.     

Postexercise energy expenditure following upper body exercise

This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p greater than .05). Mean (+/- SD) values were 9.2 +/- 3.3 and 10.4 +/- 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p greater than .05) between the upper body (22.9 +/- 13.7 min) and lower body (24.2 +/- 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise.     

CONCERN FOR THE ENVIRONMENT: A CROSS-NATIONAL PERSPECTIVE

Data from the International Social Survey Program indicate considerablevariation in the desire of respondents for increased spendingon the environment in Australia, Austria, Great Britain, theUnited States, and West Germany. This paper explores this variationwith the following objectives: (1) to determine the extent towhich the social bases of environmental concern are consistentacross nations; (2) to determine how the issue of the environmenthas been politicized in the five industrialized nations, focusingon the association of Old Leftist concerns and environmentalconcern; and (3) to determine the extent to which the socialbases of environmental concern can explain the cross-nationalvariation. The study usesa regression analysis, testing variablesrepresenting the social bases of environmental concern frompast research in the United States, a scale representing commitmentto the platform of the Old Left, and dummy variables for eachcountry. The results show that the social bases of environmentalconcern are the same in the five countries studied, includinga consistent positive association of Old Leftism with environmentalconcern. However, substantial variation between countries inthe overall level of concern remains. Potential sources of theremaining variation are examined.     

TFPS 教学用运动技术影片分析系统的教学应用

TFPS 教学用运动技术影片分析系统(Teaching's Film Processing System)的应用,彻底改变了以往影片分析方法教学的一般性介绍的状况,以实验部分为核心,采用新的教学方法,借助新的教学仪器,使理论与实践相结合,大大加深了学生对这一方法的理论知识的理解和掌握,同时使学生亲自动手实验,掌握实际实验技能,大大提高了进行运动技术分析的研究能力,填补了这一教学领域的空白,使这一领域的教学水平和教学质量达到了国内领先水平和国际先进水平。     

男子赛艇运动员与训练有关的有氧无氧能力和激素变化

观察了１５名男子赛艇运动员为期３０周训练中最大做功能力、最大乳酸值、最大摄氧量及心脏形态和功能的变化及相应时期的血清睾酮、游离睾酮、皮质醇的急慢性效应。在以力量训练为主的准备期，变化较小，以专项训练为主的准备期，心功能和有氧能力明显改善。最大负荷后及高强度训练１２周后，血清睾酮降低。提示在不同训练周期中力量—耐力训练应合理安排，有利于发挥机体适应能力。