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1.
Cristina Cadenas-Sánchez Raúl Arellano Sonia Taladriz Gracia López-Contreras 《Journal of sports sciences》2016,34(3):224-231
The aim of this study was to examine spatiotemporal characteristics and joint angles during forward and backward walking in water at low and high stride frequency. Eight healthy adults (22.1 ± 1.1 years) walked forward and backward underwater at low (50 pulses) and high frequency (80 pulses) at the xiphoid process level with arms crossed at the chest. The main differences observed were that the participants presented a greater speed (0.58 vs. 0.85 m/s) and more asymmetry of the step length (1.24 vs. 1.48) at high frequency whilst the stride and step length (0.84 vs. 0.7 m and 0.43 vs. 0.35 m, respectively) were lower compared to low frequency (P < 0.05). Support phase duration was higher at forward walking than backward walking (61.2 vs. 59.0%). At initial contact, we showed that during forward walking, the ankle and hip presented more flexion than during backward walking (ankle: 84.0 vs. 91.8º and hip: 22.8 vs. 8.0º; P < 0.001). At final stance, the knee and hip were more flexed at low frequency than at high frequency (knee: 150.0 vs. 157.0º and hip: ?12.2 vs. –14.5º; P < 0.001). The knee angle showed more flexion at forward walking (134.0º) than backward walking (173.1º) (P < 0.001). In conclusion, these results show how forward and backward walking in water at different frequencies differ and contribute to a better understanding of this activity in training and rehabilitation. 相似文献
2.
Cher Ping Lim Sungsup Ra Brian Chin Tianchong Wang 《Educational Media International》2020,57(2):87-111
ABSTRACT Information and Communication Technologies (ICT) have had significant impacts on many sectors in today’s knowledge economy. In developing and emerging countries, ICT have enhanced equity, quality, and efficiency in the education sector. However, the adoption of ICT in the South Asian countries’ education sector has not been at scale and its impacts have been limited. There are several gaps and issues that are hindering the wider adoption of ICT and limiting its impacts in the education sector. Through the case studies of the adoption of ICT for education in Bangladesh and Nepal, this paper examines the gaps and issues to be addressed in order to better leverage ICT to enhance education equity, quality, and efficiency. This discussion is guided by the ICT in the education framework that has been developed by the authors, and could provide insights into the state of ICT in education and offer strategies to better leverage ICT for the education sector of other countries in South Asia and the region. 相似文献
3.
Whereas emerging technologies, such as touchscreen tablets, are bringing sensorimotor interaction back into mathematics learning activities, existing educational theory is not geared to inform or analyze passages from action to concept. We present case studies of tutor–student behaviors in an embodied-interaction learning environment, the Mathematical Imagery Trainer. Drawing on ecological dynamics—a blend of dynamical-systems theory and ecological psychology—we explain and demonstrate that: (a) students develop sensorimotor schemes as solutions to interaction problems; (b) each scheme is oriented on an attentional anchor—a real or imagined object, area, or other aspect or behavior of the perceptual manifold that emerges to facilitate motor-action coordination; and (c) when symbolic artifacts are introduced into the arena, they may both mediate new affordances for students’ motor-action control and shift their discourse into explicit mathematical re-visualization of the environment. Symbolic artifacts are ontological hybrids evolving from things with which you act to things with which you think. Students engaged in embodied-interaction learning activities are first attracted to symbolic artifacts as prehensible environmental features optimizing their grip on the world, yet in the course of enacting the improved control routines, the artifacts become frames of reference for establishing and articulating quantitative systems known as mathematical reasoning. 相似文献
4.
In human movement and sports science, manipulations of perception and action are common and often comprise the control of events, such as opening or closing liquid crystal goggles. Most of these events are externally controlled, independent of the actions of the participants. Less common, although sometimes desirable, are event manipulations that are dependent on the unconstrained movements of participants. As an example, we describe a method we used previously to manipulate vision of basketball jump shooters on the basis of on-line registration of their own movements. The shooters wore liquid crystal goggles that opened or shut as a function of specific kinematic features of these movements. The novel aspect of this method is that the criteria for detecting movement patterns and performing the appropriate manipulations are adjustable to the specific sport context and the complexity and variations of the unconstrained movements. The method was implemented as a finite state machine: a computer system that can be used for pattern recognition. We discuss this method, how it works and the potential it has for studying perceptual-motor skills in sport. Furthermore, the results of the basketball experiment are briefly summarized and complemented with new analyses. 相似文献
5.
In this commentary, we react to the recent study by Helsen, Gilis and Weston (2006) on judging offside in football. Helsen et al. claim that their data falsify the optical error hypothesis presented by Oudejans et al. (2000). However, as we will elucidate here, they misinterpret this hypothesis and present a data set that is seriously flawed, and hence not suited to test it. Therefore, their conclusions regarding the optical error hypothesis are in error. 相似文献
6.
Irene Gómez-Marí Gemma Pastor-Cerezuela Irene Lacruz-Pérez Raúl Tárraga-Mínguez 《Journal of Research in Special Educational Needs》2023,23(2):126-135
Changes in the classification of autism and Asperger's syndrome led to changes in social perception of ASD. Since last criteria, studies indicate higher levels of stigma towards ASD than towards Asperger's. These prejudices are barriers to inclusive education. Thus, it is relevant (1) to evaluate pre-service teachers' self-efficacy towards the label of ASD; (2) to evaluate pre-service teachers' self-efficacy towards the label of Asperger's and (3) to compare those results to analyse whether the use of different diagnostic labels brings about different levels of self-efficacy. One hundred and eighty-six primary education pre-service teachers participated in the current study. Two adaptations of the Autism Self-Efficacy Scale for Teachers (ASSET) were used: a version with the label of ‘ASD’ (n = 96) and another for ‘Asperger's’ (n = 90). The scores obtained by the group asked about ASD were high according to the ASSET score range, while the scores obtained by the group asked about Asperger's were medium. After comparing the results, participants asked about the label ASD showed higher levels of self-efficacy than participants asked about Asperger's. These results could be a consequence of the consolidation of the ASD diagnosis among society and the higher presence of children with ASD in schools and cultural products, among other factors. 相似文献
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Álvaro López-Samanes Diego Moreno-Pérez José L. Maté-Muñoz Raúl Domínguez Jesús G. Pallarés Ricardo Mora-Rodriguez 《Journal of sports sciences》2017,35(21):2121-2128
To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h?1; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon. 相似文献
9.
A. Cristóvão P. Ferrão R. Madeira M.L. Tibério M.J. Raínho M.S. Teixeira 《The Journal of Agricultural Education and Extension》2013,19(2):191-203
Abstract
Purpose
Information technology (IT) has tremendous potential for fostering grassroots development and the Indian government has created various capital-intensive computer networks to promote agricultural development. However, research studies have shown that information technology investments are not always translated into productivity gains due to poor computer use by employees. In this context, a research investigation was conducted to develop a Computer Utilization Model that explains how individual and organizational factors influence computer utilization in extension organizations in India. 相似文献10.
Abstract In two experiments we examined changes in the perception of action possibilities as a function of exertion. In Experiment 1, participants repeatedly climbed on a climbing wall in a series of trials that progressively increased in number to 10 trials, resulting in increased exertion. Before and during climbing, the participants judged their maximum reaching height and perceived exertion. On a separate day, participants climbed another 10 trials while performing actual maximum reaches. Higher perceived exertion was associated with decreases in perceived maximum reach while the actual reaches did not decrease. However, the perceptual changes occurred early during task execution when the participants were not yet fatigued. When exertion set in, neither perceived nor actual maximum reaching appeared to be affected. In Experiment 2, we included exhaustion trials. The findings replicated the early changes in perception observed in Experiment 1, which may be explained by hands-on experience with the task. Furthermore, while climbing to exhaustion, perceptual judgements largely changed in keeping with changes in the actual maximum reach. Thus, there appeared to be a functional relationship between participants' actual action capabilities, rather than their state of physical fatigue per se, and perceived action possibilities. 相似文献