共查询到20条相似文献，搜索用时 31 毫秒
1.
Heather R. Bowles James R. Morrow Jr. Bruce L. Leonard Margaret Hawkins Paul M. Couzelis 《Research quarterly for exercise and sport》2013,84(4):464-470
Recent experiments on the ski simulator produced ambiguous results and raised unanswered questions concerning the true nature of “novice” behavior and the occurrence of behavioral changes during learning. The aim of the present experiment was to analyze the evolving behavior of three beginners during six practice sessions on a ski simulator. The position of the apparatus platform was recorded as time series and used for constructing dynamical models, including stiffness and damping functions. The results showed that novices tended to exploit a Rayleigh damping behavior during the first trials and then transition toward a van der Pol damping. These results replicate previous observations by Nourrit, Delignières, Caillou, Deschamps, and Lauriot (2003) and suggest the transition to the expert behavior could arise early in practice, when the task is of moderate difficulty. The discussion focuses on the properties of the observed learning dynamics and proposes a global conceptualization for acquiring complex motor skills. 相似文献
2.
This study examines the effects of a self-controlled use of physical assistance devices on learning a complex motor skill (i.e., producing slalom-type movements on a ski simulator). Physical assistance was provided by ski poles. One group of learners (self-control) was provided with the poles whenever they requested them, whereas another (yoked) group had no influence on the pole/no-pole schedule. While there were no group differences during the practice phase (Days 1 and 2), clear group differences emerged in the retention test without poles (Day 3). The self-control group produced significantly larger amplitudes than the yoked group. These results extend previous findings by showing learning advantages of the self-controlled use of physical assistance devices in complex motor skill learning. 相似文献
3.
Thibault Deschamps Déborah Nourrit Nicolas Caillou Didier Delignières 《Journal of sports sciences》2013,31(9):867-874
The aim of this study was to assess the effect of stress on a previously acquired motor coordination. Following a longitudinal learning experiment, four participants performed oscillations on a ski simulator, either in normal or stressful conditions. The results showed that the amplitude of the oscillations decreased under stress, but no significant effect was seen regarding coordination, suggesting the strong resistance to stress of overlearned behaviour. Nevertheless, for one participant, a transient regression towards a former stage of learning was observed. This result was consistent with the regression hypothesis formulated by Fuchs (). 相似文献
4.
The aim of this study was to assess the effect of stress on a previously acquired motor coordination. Following a longitudinal learning experiment, four participants performed oscillations on a ski simulator, either in normal or stressful conditions. The results showed that the amplitude of the oscillations decreased under stress, but no significant effect was seen regarding coordination, suggesting the strong resistance to stress of overlearned behaviour. Nevertheless, for one participant, a transient regression towards a former stage of learning was observed. This result was consistent with the regression hypothesis formulated by Fuchs (1962). 相似文献
5.
随着新课标的实施,"好课"又成为了一个新问题.结合教学实践提出有可能是"好课"的必须具有"充分体现了学生的主体作用,促进了全体学生的全面发展,形成了良好的课堂学习氛围"的特征,同时指出要想上"好课"必须处理好健身与技能、继承与创新、面面俱到与亮点的关系. 相似文献
6.
文章运用文献资料法、逻辑分析法等研究方法,结合自身学习、探索与教学实践,以醉拳的基本特征、功能价值及技能训练要点为选题,从醉拳手法、步法、身法的特征及训练要点进行剖析。旨在分析醉拳的基本特征,为醉拳技能的训练提供科学的指导作用,也为运动员科学选材提供合理的理论参考,醉拳练习者在学习技术的同时,应进行客观和理智的分析,从而能真正理解醉拳的拳种内涵。 相似文献
7.
Masahide Murakami Masato Iwase Kazuya Seo Yuji Ohgi Reno Koyanagi 《Sports Engineering》2014,17(4):217-225
Ski jumping flight posture was analyzed for achieving large flight distance on the basis of high-speed video images of the initial 40 m part of 120-m ski jumping flight. The time variations of the forward leaning angle and the ski angle of attack were measured from the video images, and the aerodynamic forces were calculated from the kinematic data derived from the images. Some correlations were investigated between the initial-speed corrected flight distance and such parameters as the angles of jumper, the initial transition time and the aerodynamic force coefficients. The result indicated that small body angle of attack was a key for large flight distance in the initial phase of flight because of small drag force, and that the most distinctive fault of beginners was too large body angle of attack and ski angle of attack leading to aerodynamic stall. Too small drag force does not give an optimal condition for large flight distance because the lift force is also too small. The ratio of the lift to the drag was larger than 0.95 for advanced jumpers. 相似文献
8.
双任务中内隐运动技能学习对提高保持成绩的作用 总被引：1，自引：1，他引：0
本实验研究的目的是,调查在双任务条件下一个运动系列能否被不觉察地掌握,内隐学习是否比外显学习更有效地增加保持.36名实验对象被随机分为内隐学习组或外显学习组.要求所有被试通过敲击一个键盘上的F和J键,来移动计算机屏幕上的横杆,去接住一个下落的小球.一个固定的5种小球下落曲线的系列被安插在每组15次练习的中段.同时,实验参加者需要数每组练习中的所听到的嘟嘟声的数目,以作为第二项任务.在掌握该技能后的24小时进行3次保持测验.ANOVA分析发现固定小球下落曲线段的接球成绩随着练习的增加而提高,但是练习对随机段没有作用.尽管两种练习条件下,运动技能学习成绩没有差异,但内隐学习组比外显学习组在模拟接球的保持测试和第二项任务中表现较准确.这些结果显示内隐学习是一个改善运动技能长期记忆的有效手段,并且与外显学习相比,它在练习中占用较少的认知资源. 相似文献
9.
高山滑雪是具有显著北方特色的运动项目,是北方很多高校体育院系的必修课程,在教学中如何以先进的教育理念来指导教学已经成为滑雪教学改革的关键。利用教学实验法,通过“合作教学模式”开展高校高山滑雪技术教学。结果表明：合作教学模式应用于高校高山滑雪技术教学中是切实可行的,这种教学模式对于学生观察分析滑雪技术、提高学生技能的掌握、教学评价以及改善学生的学习态度等方面优于传统的教学模式,能够对学生起到“在合作中学习,在学习中合作”的作用。 相似文献
10.
Konstantin I. Matveev 《Sports Engineering》2017,20(4):293-298
This paper addresses sliding friction of a ski during steady horizontal gliding on snow. A simple mathematical theory accounting for both dry and wet friction is developed. The water film evolution along a ski is calculated with a lumped-element thermal model. An analytical solution is obtained for the ski friction force. Representative calculation results are demonstrated for a range of ski velocity, contact surface area fraction, snow temperature, and ski aspect ratio. 相似文献
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12.
A four-component aiming movement was used to examine the relative effectiveness of part and whole practice. Following a pretest, participants were assigned to one of three practice groups. Participants in a "Whole" group practiced the four components together as a unit. A "No Overlap" group practiced the first two and last two components of the task, alternating every fifth trial. An "Overlap" group practiced the transition between the second and third components on every trial by alternating practice of the first three and last three components every five trials. Participants in all groups improved significantly from pretest to immediate posttest and maintained their performance over a 24-hr delay. Contrary to the "chunking hypothesis," participants in the No Overlap group improved as much as those in the other two groups. Kinematic data indicated that participants in all three groups learned to use response-produced feedback earlier in the individual movement trajectories. Moreover, participants appeared to acquire a general ability to make transitions between movement components rather than specific transitions. The results suggest that segmented or segmented "overlap" practice regimes may benefit learning movement sequences of short duration. 相似文献
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14.
为减少我国大众滑雪伤害事故的发生,支持"3亿人参与冰雪"战略,采用数理统计法和案例分析法,研究近年大众滑雪伤害事故特征,结合案例论证滑雪场责任的法律基础、具体义务和过错类型。发现：大众滑雪伤害事故后果严重;案件属于侵权责任纠纷,责任认定较为简单;依据《侵权责任法》（2021年后为《民法典》）等法律,滑雪场有安全保障义务,具体可分为5类;司法实践中存在滑雪场担责比例偏高问题,"自甘风险"条款的确立可能加重该问题。建议：政府应强化监管和惩处力度;业界建立经验交流与赔偿协商机制;滑雪者应养成良好滑雪行为习惯;滑雪场应积极购买附高风险运动的意外伤害责任保险并提高额度。 相似文献
15.
A new sensor for detecting ski bending and torsional deflection during an actual ski turn on the snow has been developed.
It consisted of bending and torsion sensors connected by light rigid beams. This structure was fixed to the upper surface
of a ski and passed through a tunnel in the central binding plate. The bending and torsion sensors were strain cells, designed
to reject strain orthogonal to the desired measurement direction. The calibration factor for each sensor was determined in
a jig, then the calibration of the overall sensor assembly was checked by static bending experiments and a free vibration
test. A data logger recorded the strain signals synchronously with other data such as the components of the earth’s magnetic
field measured by a sensor on the ski. The data set allowed reconstruction in software of the instantaneous shape, direction
and edge angle of the ski. The purpose of this paper is mainly to introduce the equipment used and methods developed. Tests
of the sensor performance are described. Results from a ski run on snow are presented to show how the various types of data
can be combined. A skilled ski athlete performed long turns with the ski at about 60 km/h on a groomed snow surface at Shiga
Kogen in Japan. The experiment on snow showed that the deformation of the ski was predominantly bending; torsional deflection,
although measurable, had only a small effect on the shape of the running edge. The ski edge adopted a symmetrical circular
bent shape with an unexpectedly small radius when on the outside, but was unconstrained, lightly loaded and nearly straight
when on the inside. 相似文献
16.
Optimizing generalized motor program and parameter learning 总被引：1，自引：0，他引：1
Two experiments examined generalized motor program (GMP) and parameter learning. Experiment 1 examined the effects of bandwidth knowledge of results (KR) about relative timing in constant and variable practice. The purpose was to determine if movement stability created by the bandwidth manipulation is associated with increased GMP learning and if bandwidth KR interacts with constant and variable practice. Participants were asked to depress four keys sequentially, using the same relative timing structure. Constant practice had one absolute timing requirement, whereas variable practice had three different absolute timing requirements. The results indicated that GMP learning was enhanced by constant practice (independent of the bandwidth KR condition) and by bandwidth KR, when variable practice was used. The findings suggest practice conditions (bandwidth KR, constant practice) that increase movement stability during practice enhance GMP learning. Parameter learning (during transfer), however, was enhanced by variable practice. Experiment 2 attempted to determine how constant and variable practice conditions could be combined to enhance both GMP and parameter learning. The results indicated that developing a stable GMP early in practice--by providing learners with constant practice early in practice--and refining parameter learning later in practice--by providing them with variable practice late in practice--were effective for both GMP and parameter learning. This suggests a hierarchy in the development of programmed actions with a stable GMP being a requisite for developing an effective and stable parameter rule. 相似文献
17.
Recent studies (Chiviacowsky & Wulf, 2002, 2005) have shown that learners prefer to receive feedback after they believe they had a "good" rather than "poor" trial. The present study followed up on this finding and examined whether learning would benefit if individuals received feedback after good relative to poor trials. Participants practiced a task that required them to throw beanbags at a target with their nondominant arm. Vision was prevented during and after the throws. All participants received knowledge of results (KR) on three trials in each 6-trial block. While one group (KR good) received KR for the three most effective trials in each block, another (KR poor) received feedback for the three least effective trials in each block. There were no group differences in practice. However the KR good group showed learning advantages on a delayed retention test (without KR). These results demonstrated that learning is facilitated if feedback is provided after good rather than poor trials. The findings are interpreted as evidence for a motivational function of feedback. 相似文献
18.
Bulge-disc type pressure sensors of diameter 6 mm were fitted as near as possible to the running edge of a modern carved ski.
The pressure signals were sampled at 30 Hz during long turns on snow, synchronously with signals from a geomagnetic compass
and a pressure pad in the ski boot. The pressure from the snow was found to be highly variable with a mean value of about
50 kPa and dynamic pressure spikes up to 300 kPa. With the outside leg, the snow contact width in the rear part of the ski
was found to be slightly wider, on average, than for the front part, as expected for a carving turn. Correlation within the
pressure sensor data showed that the rapid pressure fluctuations were probably not due to bumps or features on the snow; instead
they were probably caused by many small-scale collapses of the snow structure as the ski passed. 相似文献
19.
Takeshi Yoneyama 《Sports Engineering》2018,21(4):277-282
The relation between the ski side-cut radius and deflection during a turn has been investigated. Using a model wherein the ski slides along a turn of a constant radius with an edging angle, it was found that the side-cut radius increases and the ski-deflection radius decreases as the edging angle increases. Even if additional deflection is necessary in the front part of the ski to form the turn groove, the side-cut radius is still the same in the groove. Owing to the constant side-cut radius of existing skis in the turn groove with a large edging angle, the top wide part of the ski causes an increase in skiing resistance. To reduce the skiing resistance, a prototype variable side-cut ski was fabricated, and test skiing was performed. Athletes felt more stable in the turn with the variable side-cut ski and found it easier to increase speed. 相似文献
20.
吴晓华 《哈尔滨体育学院学报》2008,26(1)
近几年滑雪俱乐部数量快速增加,而目前我国关于滑雪俱乐部的研究几乎是空白,由于黑龙江省滑雪运动始终处于全国的"领跑"地位,因此本文将以黑龙江省滑雪俱乐部为起点,分析滑雪俱乐部的发展现状、特点及存在问题,并总结一些合理的建议,以引导我省滑雪俱乐部健康有序地发展。 相似文献