Physical activity levels of 5-11-year-old children in England as determined by continuous observation.

Continuous observation of the physical activity of 56 preadolescent children was conducted in four regions of England from October 1988 to July 1989. Observations were undertaken during school break times, lunch times, and physical education lessons, as well as during the children's free time. Of total time observed, the children spent 32.4% of it engaged in moderate to vigorous physical activity (MVPA). Children were shown to be most active during school breaks and least active during free time at home. However, it is thought that cardiorespiratory benefits are best achieved by participation in sustained periods of MVPA. Only 8 (14%) of the 56 children were observed to participate in MVPA for sustained periods of 20 min or longer. A random sample of 55 physical education lessons was observed. Only 6 children engaged in MVPA for sustained periods of 5 min or more, and no children participated in MVPA for 10 min or longer. The implications of these results are that, although the children engaged in a reasonable amount of MVPA, it may not have been sustained for periods of sufficient length to produce a cardiovascular training response. Consideration is given to ways of promoting lifelong involvement in physical activity.     

训练及类固醇药物对动物骨、肌肉肌腱和韧带生物力学特性的影响

本实验对训练动物予以类固醇药物,发现其肌力增强,但工作时间缩短,肌肉断裂强度和能量吸收无改变。胫骨、跟腱、屈趾肌腱和膝内侧副韧带的某些生物力学特性受到不同程度的影响,使其在激烈运动中易于受伤。     

Social Perceptions of Students with Learning Disabilities Who Differ in Social Status

As a group, students with learning disabilities (LD) have social difficulties. One possible explanation for these difficulties is the unique way they process social information. Although students with LD may differ from their nondisabled peers in their social cognition, investigators have suggested the presence of subgroups within the population of students with LD who may differ in their social competence and, thereby, shed light on the source of the difficulties. The present exploratory study examined how two subgroups of students with LD in inclusive settings, students with high and low social status, perceive social situations. Using a sociometric technique, three students with LD receiving high social‐status ratings and three students with LD receiving low social‐status ratings were identified. A qualitative approach was used to gather and evaluate data from the participants and their teachers. Results suggested differences between the two subgroups in their (1) sensitivity to cues in the environment, (2) interpretation of social situations in relation to their own experiences, and (3) levels of self‐control. Implications of these findings for practice and future research are discussed.     

Adapting Adaptive Testing: Using the MicroCAT Testing System in a Local School District

What is the rationale for adapting an existing testing system instead of developing your own? What are the limitations of MicroCAT? What has to be modified in order to meet local needs and to realize the potential of adaptive testing in the context of an existing testing system?     

浅谈如何上好艺术体操选修课

对普通高校艺术体操选修课教学从形体姿态的培养、教学成套动作的编排,音乐的选择及口令、手势的运用等,进行了分析探讨.