自控示范策略对动作技能学习的影响

示范在动作技能教学中的作用已为人们普遍认同,但自控示范尚却鲜为人知.以实验法为主要方法,以篮球原地单手肩上投篮为主要内容,随机抽取广州大学二年级女子健美操专选班20名右利手女生作为实验对象(实验组、对照组各10名),按照实验法规定的程序,进行为期两天的教学实验,以探讨自控示范策略对动作技能学习的影响.研究结果表明:在获得阶段,随着练习次数的增加,两组受试者的练习绩效增加,但组间差异不显著;在保持阶段,实验(自控)组受试者的学习成绩优于对照(被动)组受试者的学习成绩,组间差异显著.     

功能性训练促进5－6岁幼儿粗大动作发展的实证研究

目的：探讨功能性训练对5－6岁幼儿粗大动作能力发展的影响。方法：随机抽取石家庄某公立幼儿园5－6岁幼儿143名为研究对象,将其分为实验组与对照组,实验组70人,对照组73人。实验组进行12周的功能性训练干预,对照组保持幼儿园原有体育活动内容,干预前后,通过美国大肌肉动作技能发展测试系统第二版（ TGMD －2）,对受试幼儿粗大动作能力进行测试。结果：（1）对照组幼儿粗大动作总分为74．65,其中位移动作得分39．82、控制动作得分34．83,较实验前74．61、38．86和35．75,未见显著性提高（P ＞0.05）;（2）实验组幼儿粗大动作总分为85．74,其中位移动作得分44．60、控制动作得分41．14,较实验前74．22、39．62和34．60,具有非常显著性提高（P ＜0.01）;（3）实验后实验组与对照组幼儿相比,实验组粗大动作、位移动作和控制动作得分均显著性高于对照组（ P ＜0.01）。结论：根据幼儿身心特点所设计的功能性训练能够较好促进5－6岁幼儿粗大动作水平发展。     

韵律性身体活动改善幼儿侧滑步下肢积分肌电贡献率的研究

目的：从动作发展的视角出发,将幼儿阶段应掌握的基本动作技能设计到韵律性身体活动中,通过分析幼儿侧滑步下肢肌肉放电情况的变化,比较这种新幼儿韵律性身体活动与一般性幼儿韵律性活动效果差异。方法：将38名受试对象按照年龄随机分为实验组与对照组,实验组幼儿周一至周五每天进行动作发展视角下的韵律性身体活动,每天累计活动时间为20－30分钟,运动干预周期为一年。对照组则进行一般性的韵律性身体活动。运动干预前后,记录受试者侧滑步时下肢肌电活动,选取积分肌电值、下肢主要肌群积分肌电贡献率为指标评估幼儿下肢肌电活动的变化。结果：（1）运动干预后,实验组与对照组的积分肌电贡献率较运动干预前的整体变化为主动肌积分肌电贡献率的上升和拮抗肌积分肌电贡献率的下降。（2）运动干预后,侧滑步第一时相中,实验组3岁组幼儿腓肠肌（右）积分肌电贡献率显著高于对照组,股直肌（右）积分肌电贡献率显著低于对照组;5岁组幼儿腓肠肌（左）的积分肌电贡献率显著高于对照组,股二头肌（左）积分肌电贡献率显著低于对照组。结论：运动干预后,实验组幼儿的侧滑步动作发展水平都有了提高,在做侧滑步时对主动肌与拮抗肌的控制变得更加协调;动作发展视角下的韵律性身体活动在改善幼儿侧滑步动作下肢肌肉放电情况,促进幼儿侧滑步动作发展方面优于一般性的韵律性身体活动。     

电动汽车用外转子双凸极永磁电机建模与仿真

提出了一种新的建模方法,即在双凸极永磁电机电磁场有限元计算的基础上,利用非线性等效磁网络对双凸极永磁电机进行非线性建模与仿真。最后,用提出的非线性建模和仿真的计算方法,对一台三相12/8极双凸极永磁电机的相绕组电感和动态转矩进行了仿真。结果表明:相绕组电感和动态转矩的仿真与实验结果一致性较好。     

The influence of wearing ski-boots with different rigidity characteristics on postural control

Abstract

External supports that reduce ankle joint mobility such as ski-boots can impair postural control of healthy participants. Although this disruptive effect has been attributed to the rigidity of the external supports, the results remained controversial and no study has been conducted in order to evaluate the influence of ski-boots rigidity. Hence, the question about the influence of ankle support rigidity on postural control remains open. This study was therefore undertaken in order to investigate the effect of ski-boots rigidity on postural control. Ten healthy active participants were recruited. The wearing of soft and rigid ski-boots was compared to barefoot while standing on a seesaw generating mediolateral and anteroposterior instability. Centre of pressure displacements were sampled with a force platform. The surface electromyographic activity of the main muscles from the leg, thigh and trunk was recorded. A motion analysis system was also used to calculate the ankle, knee and hip angles. The results did not reveal any negative influence of ski-boot rigidity on postural control but rather suggest a less active postural control with the rigid ski-boots which offered a higher mechanical contribution.     

'Raising the bar': views on play and training in the Move & Walk pedagogy

In this study 20 beginning special education teachers were asked to describe their experiences in general education settings. To provide data, each teacher completed approximately three electronic reflective journals during a school year and also participated in a phone interview, which was aimed to give in-depth information regarding the participants’ comments in the journals. The participants described their experiences in regard to collaboration with mainstream teachers, the delivery of the curriculum and the understanding of their role with reference to identity. They reported some good experiences but also many difficulties in their attempts to support pupils with special educational needs (SEN) and enhance their learning and participation in mainstream schools. Challenges in collaboration, the delivery of the curriculum and the development of teachers’ identity at the beginning of a career in special education are discussed. We argue that the teachers’ experiences are associated with the legislative educational system and the school culture which does not encourage collaborative practices but rather promotes individualism and leads to exclusive practices.     

Confirmatory Factor Analysis of the Test of Gross Motor Development-2

The purpose of this study was to examine the underlying structure of the second edition of the Test of Gross Motor Development-2 (Ulrich, 2000 Ulrich, D. A. 2000. Test of gross motor development: Examiner's manual, 2nd, Austin, TX: Pro-.  [Google Scholar]) as applied to Chinese children. The Test of Gross Motor Development-2 was administered to 626 Hong Kong Chinese children. The outlier test with standard scoring was utilized. After data screening, a total of 614 cases (N = 614) were used for further analysis. The two-factor structure of the Test of Gross Motor Development-2 was tested using confirmatory factor analysis with maximum likelihood estimation to compute parameter estimates and to select the appropriate item for each factor. The goodness-of-fit indices supported that the model was tenable (goodness-of-fit index = .95, root mean square error of approximation = .06, standardized root mean square residual = .04, comparative-fit index = .97). The findings of this study suggested that the two-factor structure proposed by Ulrich (2000 Ulrich, D. A. 2000. Test of gross motor development: Examiner's manual, 2nd, Austin, TX: Pro-.  [Google Scholar]) fit the data of Hong Kong Chinese children.     

A review of batting in men’s cricket

In this review, we critically evaluate the scientific research into the morphology and physiology of cricket batsmen. We consider all aspects of the motor control of this skill, in the context of research into dynamic interceptive actions, the biomechanics (kinematics and kinetics) of the various phases of batting strokes and injuries to batsmen. Some attention is also devoted to batting equipment and to psychological factors in batting. Because of the lack of published scientific research into women's cricket, this review focuses on the men's game and covers research on batsmen of various playing standards. For the future, we see as a high priority research into injury mechanisms, rather than simple injury statistics, and the role of cricket equipment design in injury prevention. A second priority is for multi- or inter-disciplinary research, linking the biomechanics of batting to the underlying motor control of the movements and the effect of environmental information. Biomechanical studies of the variability of the batsman's movements are needed, and these should be related to the compensatory variability proposal of ecological psychology. Clearly, there is also a need for scientific research into batting in women's cricket, which has been inadequately researched to date.     

The effect of video‐feedback on the learning of the tennis service by intermediate players

Effects of video‐feedback on improvement of the tennis service were investigated in subjects having at least 2 years of playing experience in tennis. The experiment was carried out in an indoor tennis hall under normal training conditions.

Subjects were randomly divided into three groups: a video‐feedback training (VFT) group, a traditional training (TT) group and a control group, each consisting of 22 subjects. While the subjects of the control group received no training at all, subjects in both the VFT and TT groups were trained twice weekly during 5 consecutive weeks. Each training session lasted 40 min, of which 30 min was spent on actual practice in training of the service. The remaining 10 min was spent on watching, analysing and discussing video recordings of either their own service performed during the training session (VFT group), or ground strokes and volleys of top level players (TT group). Both the VFT and TT group showed significantly greater improvements in both achievement scores and form (technique) scores than did the control group. No differences, however, could be demonstrated between the VFT and TT group, indicating that the subjects of the former group did not benefit from the video‐feedback they received.

While form scores correlated significantly (P < 0.001) with the velocity of the served ball, no such relation between form scores and spatial accuracy was apparent.     

Biomechanics feedback for rowing

Factors that affect boat speed are important determinants of rowing performance and should form the basis of feedback to rowers and their coaches. Biomechanical analysis of rowing has led to variables that are causally linked to boat speed. With modern technology, these variables can be measured and feedback can be presented instantaneously on-water, or be presented simultaneously with video after the event. This paper demonstrates the links between the criterion of success in rowing, the time for completing 2000 m and the forces acting on the boat, and describes an instrumentation system for providing feedback of these variables to rowers and coaches. These feedback techniques have been used with rowers from national to Olympic competition standard. Aspects of technique have been linked to the determinants of boat speed and several examples are presented here. The motor learning literature supports the effectiveness of kinetic information feedback for the improvement of motor skill and provides a relevant conceptual framework for the improvement of rowing performance. However, although rowers and their coaches value this feedback, further research must be undertaken to establish a sound basis for comparing the effectiveness of such feedback compared with traditional styles, such as verbal feedback of performance.