The effects of augmented kinematic feedback on motor skill learning in rifle shooting

In this study, we examined the effects of augmented kinematic knowledge of performance (KP) on shooting performance and learning. Knowledge of performance described the aiming trajectory of the rifle barrel. The effects of knowledge of performance were evaluated in terms of shooting accuracy (shooting score), variability of the shooting score (root mean square error) and rifle stability (x- and y-deviation of rifle movement). The participants (n = 40) were randomly assigned to one of four groups: no-KP, 50% KP, 100% KP and a control group. The three experimental groups performed 480 shots during a 4 week acquisition phase in which feedback was provided. No-feedback retention tests were administered at 2 and 10 days after acquisition. There were no differences between groups during acquisition. In the 2 day retention test, the mean shooting score of the group receiving 100% knowledge of performance was significantly higher than that of the other groups. Furthermore, variability in shooting score for the 100% KP group was lower than that for the 50% KP and control groups. No significant differences were found in rifle stability between the experimental groups. In summary, a high frequency of kinematic knowledge of performance improved shooting accuracy, but the effect appeared to be temporal, disappearing in the 10 day retention test. Given that a parallel effect was not found in rifle stability, future research should focus on examining the reasons for this improvement in shooting score.     

Children writing ethnography: children's perspectives and nomadic thinking in researching school classrooms

This article makes a connection between narrative ethnography, childhood studies and new materialist theories in studying children's perspective on school. It presents ‘children writing ethnography’ as an approach based on complexity and involving participatory research. The question of ‘what is happening in the classroom’ is explored through writings produced in class by 10-year olds. The ‘messy’ ethnographic data are examined within the framework of narrative ethnography using the idea of ‘small stories’ that capture everyday interaction. Furthermore, both material and embodied meanings in the writings are discussed. New materialist theories and the idea of nomadic make it possible to account for the connectivity between the writings, the classroom reality, the child-ethnographers and the research, which are seen as mutually producing one another. The author suggests that engaging with children's free-flowing ethnographic writing serves as a productive way to conduct participatory ethnographic research, as well as to investigate contemporary childhoods in all their complexity.     

The effects of augmented kinematic feedback on motor skill learning in rifle shooting

Abstract

In this study, we examined the effects of augmented kinematic knowledge of performance (KP) on shooting performance and learning. Knowledge of performance described the aiming trajectory of the rifle barrel. The effects of knowledge of performance were evaluated in terms of shooting accuracy (shooting score), variability of the shooting score (root mean square error) and rifle stability (x- and y-deviation of rifle movement). The participants (n = 40) were randomly assigned to one of four groups: no-KP, 50% KP, 100% KP and a control group. The three experimental groups performed 480 shots during a 4 week acquisition phase in which feedback was provided. No-feedback retention tests were administered at 2 and 10 days after acquisition. There were no differences between groups during acquisition. In the 2 day retention test, the mean shooting score of the group receiving 100% knowledge of performance was significantly higher than that of the other groups. Furthermore, variability in shooting score for the 100% KP group was lower than that for the 50% KP and control groups. No significant differences were found in rifle stability between the experimental groups. In summary, a high frequency of kinematic knowledge of performance improved shooting accuracy, but the effect appeared to be temporal, disappearing in the 10 day retention test. Given that a parallel effect was not found in rifle stability, future research should focus on examining the reasons for this improvement in shooting score.     

The developmental dynamics of task-avoidant behavior and math performance in kindergarten and elementary school

Besides cognitive factors, children's learning at school may be influenced by more dynamic phenomena, such as motivation and achievement-related task-avoidant behavior. The present study examined the developmental dynamics of task-avoidant behavior and math performance from kindergarten to Grade 4. A total of 225 children were tested for their arithmetic skills in kindergarten and in Grades 1, 2, and 4 of elementary school. Children's task-avoidant behavior in learning situations was rated by their teachers. The results of latent growth curve analyses showed that math performance and task-avoidant behavior develop in tandem: an increase in task-avoidant behavior was related to less improvement in math performance. Furthermore, a high initial level of task-avoidant behavior predicted less improvement and slower improvement in math later on.     

Release parameters at the foul line and the official result in javelin throwing

Range in javelin throwing is determined by the release parameters and aerodynamic factors. The current study was designed to investigate the effects of release speed, release angle and uncorrected angle of attack measured at the foul line on the official javelin throwing result. The data were collected in international competitions for 26 elite male and 15 elite female javelin throwers (total 248 throws). Multiple regression models were constructed to predict the range of throw for a) individual throwers, b) a group of throwers using the mean value for each thrower in the analysis, and c) all individual throws registered for each gender separately. The data collection was carried out using a computerised photocell gate that consists of two invisible infrared walls two metres apart, perpendicular to the throwing direction. Release speed was found to have the highest correlation with the official throwing result. The three release parameters accounted for 56% of the variance in the official result for the male and 51% for the female throwers. For individual male and female throwers, the variance explained by the model was between 46 and 87%. Among the individual male throwers an increase of 1 m.s-1 in the release speed from 29 to 30 m.s-1 was calculated to increase the official result between 2.12 to 6.14 m while among the female throwers the effect of increase from 24 to 25 m.s-1 in the release speed was from 2.25 to 3.68 m. The study emphasises the importance of investigating javelin throwing biomechanics on an individual thrower basis.     

The role of reading difficulties in the associations between task values,efficacy beliefs,and achievement emotions

Reading and Writing - The aim of this study was to examine the situational associations of reading-related task values and efficacy beliefs with achievement emotions, and whether these associations...     

Thinking skills intervention for low-achieving first graders

This paper reports the results of the improving thinking skills (ITS-1) intervention study on the thinking skills of low-achieving first graders. The intervention programme consists of 12 lessons, each lasting for 45 min. Lessons offer enriched-discovery learning activities and tasks to be solved through inductive reasoning. We used a quasi-experimental approach, with pre-, immediate post- and delayed post-tests conducted among intervention and control groups. The following groups were formed from a total of 149 first graders on the basis of the thinking skills measure: low-achieving (SD) intervention group (LowI) (n = 9) and two control groups, comprising both low-achieving (LowC) (n = 18) and well-performing (≥?1 SD) groups (WellC) (n = 122). Thinking skills, mathematical skills, listening comprehension skills and reading fluency were measured. The results showed that in the beginning of the study, there were differences in thinking skills, mathematical skills, listening comprehension skills and reading fluency between the LowI and WellC groups, but the LowI group was able to reach the level of their well-performing peers at the end of the intervention in all measures. The discussion focuses on the implications of intervention research, educational practice and responsiveness to intervention.     

Effects of nicotinamide adenine dinucleotide hydride on physical and mental performance

The aim of this study was to assess the effects of nicotinamide adenine dinucleotide hydride (NADH) on maximal oxygen uptake (VO2max), maximal anaerobic running time, and mental performance. Eight men were exposed to a supplement treatment (30 mg NADH as ENACHI tablets per day) and to a placebo treatment, each of 4 weeks' duration, in a balanced, double-blind, and cross-over design. The two treatments were separated by a 14-week wash-out period. The results indicated that VO2max, maximal anaerobic running time, and the ability to concentrate were similar in the NADH and placebo conditions. There were also no differences in blood lactate, creatine kinase, reaction time or feelings of fatigue between the treatments. A counter-movement jump performed at rest and 2 min after the aerobic test differed significantly (P 相似文献   

Cognitive Correlates of the Covariance in Reading and Arithmetic Fluency: Importance of Serial Retrieval Fluency

This study examines the core predictors of the covariance in reading and arithmetic fluency and the domain-general cognitive skills that explain the core predictors and covariance. Seven-year-old Finnish children (N = 200) were assessed on rapid automatized naming (RAN), phonological awareness, letter knowledge, verbal counting, number writing, number comparison, memory skills, and processing and articulation speed in the spring of Grade 1 and on reading and arithmetic fluency in the fall of Grade 2. RAN and verbal counting were strongly associated, and a constructed latent factor, serial retrieval fluency (SRF), was the strongest unique predictor of the shared variance. Other unique predictors were phonological awareness, number comparison, and processing speed. Findings highlight the importance of SRF in clarifying the relation between reading and arithmetic fluency.     

The role of achievement strategies on literacy acquisition across languages

We examined the importance of children’s achievement strategies in different literacy outcomes in three languages varying in orthographic consistency: Chinese, English, and Greek. Eighty Chinese-speaking Taiwanese children, 51 English-speaking Canadian children and 70 Greek children were assessed on measures of phonological awareness, rapid automatized naming, reading fluency, and spelling. The children’s use of a task-focused versus task-avoidant achievement strategy in the classroom context was rated by their teachers. The results indicated that the teacher-rated task-focused behavior was a significant predictor of spelling and to a lesser extent of reading fluency and that its effects were comparable across languages.