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1.
We tested the hypothesis that quiet eye the final fixation before the initiation of a movement in aiming tasks, is used to scale the movement's parameters. Two groups of 12 participants (N=24) threw darts to targets in the horizontal and vertical axes under conditions of higher (random) or lower (blocked) target variability. Supporting our predictions, random practice and target changes in the vertical axis led to longer quiet eye duration than did blocked practice and target changes in the horizontal axis. Our data suggest that quiet eye is not simply a mediating factor in accuracy, but is responsive to the task's programming demands, being influenced by the necessity to reparameterize the movement from one trial to the next.  相似文献   

2.
Abstract

The generality of the variability in practice prediction, arising from Schmidt's schema theory (1975) of motor learning was tested on young children. More specifically, the structure of the variability session and its subsequent influence on transfer performance to a novel variation of the task was examined. Children tossed a weighted bean bag to a fixed target location. Three groups experienced variability in practice with four bean bags of varying weights (3, 4, 5, and 6 oz.); however, the trial-by-trial presentation of each weight was different for each group. One group received a random presentation of each weight from trial to trial while another experienced random presentations of a weight for blocks of three trials. The third variability group received blocked practice with six trials per block for each weight. All variability groups experienced the same amount of practice at each weight. A constant practice group experienced only a single weight. Following 24 practice trials, all subjects transferred outside the range of previous experience, receiving three trials with one of two possible test weights (2 oz. or 7 oz.). The results indicated that the variability group practicing with blocks of three trials at each variation led to superior performance at transfer to novel variations of the task. Overall, the experiment suggested that transfer performance for children is affected by the appropriate structure of variable practice which formulates the schemata for movement production.  相似文献   

3.
Abstract

In this study, we examined how individuals controlled their gaze behaviour during execution of a far aiming task and whether the functional relationship between perception and action was disrupted by increased anxiety. Twenty participants were trained on a simulated archery task, using a joystick to aim and shoot arrows at the target, and then competed in two counterbalanced experimental conditions designed to manipulate the anxiety they experienced. The specific gaze behaviour measured was the duration of the quiet eye period. As predicted, accuracy was affected by the duration of the quiet eye period, with longer quiet eye periods being associated with better performance. The manipulation of anxiety resulted in reductions in the duration of quiet eye. Our results show that the quiet eye period is sensitive to increases in anxiety and may be a useful index of the efficiency of visual orientation in aiming tasks.  相似文献   

4.
Abstract

The contextual interference (CI) effect has been replicated many times since its first demonstration by Shea and Morgan (1979) in the motor learning domain (see Brady, 1998; Magill&;Hall, 1990). The CI effect is characterized by the observation that experiencing greater interference during acquisition is detrimental to immediate performance but enhances delayed performance as measured on retention or transfer tests. High CI is most often created by random practice in which the learning of multiple tasks occurs in a single training. In contrast, low CI is frequently created by using a blocked practice format in which all the practice trials of one task are completed before another task is introduced. One theoretical account that has been forwarded to account for the CI effect is labeled the action plan reconstruction hypothesis (Lee&;Magill, 1983, 1985). This position intimates that before a movement occurs an “action plan” must be prepared. In blocked practice, a previously prepared “action plan” is readily available from trial to trial, but it suffers from lack of attention on trials following initial retrieval from working memory. In random practice, however, each time a task must be executed a “reconstruction” of the action plan must be processed, because the interchange of information from trial to trial never allows the same information to remain in working memory for an extended amount of time. Presumably, the additional trial-to-trial preparation used by the random practice participant during practice results in a more resilient memory representation that better supports long-term recall efforts compared to their blocked practice counterparts.  相似文献   

5.
ABSTRACT

The aims of this study were to compare the force profile of using a horizontal cylinder-shaped axis or a vertical cone-shaped axis to provide resistance in rotary inertia devices, and to report the evolution of kinetic and kinematic variables in experienced athletes during a half-squat exercise. Twenty-two healthy active men participated in the assessment of time, peak velocity, peak force, time to reach the peak force, average force, impulse, and range of movement, during a half-squat incremental test performed on conical inertial device (CP) and on cylinder inertial device (YY). The analysis showed that YY during CON-ECC phased generates substantial higher peak_force, mean_force, impulse, time, and a lower peak_velocity, than CP. We never obtained eccentric overload for peak_force or mean_force. CP offers less resistance to accelerate-decelerate the movement with respect to YY, we need checking whether eccentric overload it is being produced, and the impulse was the only kinetic variable that was able to discriminate between the inertias and devices.  相似文献   

6.
Abstract

Schmidt's (1975) schema theory was tested with subjects who had to emit a rapid aiming response while wearing prism glasses. The glasses enabled them to view the target, but not their responding limb or the outcome of the movement. The problem was to determine the effect of (a) training with variable target practice, and (b) experiencing visual displacement information of the target, prior to training, on performance in transfer to a novel target distance. A 2 × 2 (type of practice × displacement information) factorial design was used, in which four groups of 15 male college subjects performed 60 training trials with verbal knowledge of results. The groups with variable target practice had less error on initial transfer to the novel target and throughout transfer than the groups with nonvariable target practice. No evidence was found to indicate that rate of learning for a novel target distance during transfer in the absence of KR is a positive function of the variability of target practice in training. Nor was any effect found for experiencing visual displacement information on performance in transfer.  相似文献   

7.
Abstract

An experimental intervention program to train subjects on coincidence anticipation and prediction skills was administered to novice females. An attempt was undertaken to study the effects of this sports training and training on laboratory tasks. According to Battig' s predictions on the structure of practice sessions, both random and blocked contexts were presented. These acquisition contexts were viewed as orienting tasks that preceded sports training. The effects of high-contextual interference and sports training on acquisition, retention, and transfer were investigated. Practice conditions in the intervention were selected because of processing demands similar to random acquisition. Other research has shown that acquisition in random is influenced by sport-skill expertise and further indicates that processing of events occurring outside the laboratory influences performance of laboratory tasks. Observed results supported prior theoretical predictions and empirical findings on contextual interference. Predicted hypotheses were supported, and the effects of sports training were most profound during retention and transfer if the acquisition context for the trained subjects was random. Supported by prior research, activities performed outside the laboratory influenced performance on laboratory tasks. These results shift more emphasis on the learner as an active processor of information, which relates to Lee's (1988) views on transfer-appropriate processing.  相似文献   

8.
Abstract

To better understand the contextual interference effect, in two experiments we investigated a form of practice schedule that provided novices with systematic increases in contextual interference. This new type of practice schedule was compared with traditional blocked and random scheduling for two types of sports skills. In Experiment 1, we tested the hypothesis that practising variations of the same task with systematic increases in contextual interference would lead to superior performance compared with blocked or random scheduling. Participants practised golf putting tasks following a blocked, random or increasing schedule, which involved initial blocked trials, followed by serial practice trials, and ended with random scheduling. Participants who followed the increasing schedule had superior retention test performance. In Experiment 2, we tested if these learning benefits were observed when learning tasks controlled by different generalized motor programs. Participants practised three different basketball passes (chest, overhead, single arm) in a blocked, random or increasing schedule. Participants practising with gradual increases in contextual interference performed better on retention and transfer tests than participants practising with blocked or random scheduling. The results of these two experiments indicate that a practice schedule offering systematic increases in contextual interference facilitates skill learning.  相似文献   

9.
Abstract

In interceptive timing tasks, long quiet eye (QE) durations at the release point, along with early tracking on the object, allow performers to couple their actions to the kinematics of their opponent and regulate their movements based on emergent information from the object's trajectory. We used a mobile eye tracker to record the QE of eight university-level ice hockey goaltenders of an equivalent skill level as they responded to shots that deflected off a board placed to their left or right, resulting in a trajectory with low predictability. QE behaviour was assessed using logistic regression and magnitude-based inference. We found that when QE onset occurred later in the shot (950?±?580?ms, mean?±?SD) there was an increase in the proportion of goals allowed (41% vs. 22%) compared to when QE onset occurred earlier. A shorter QE duration (1260?±?630?ms) predicted a large increase in the proportion of goals scored (38% vs. 14%). More saves occurred when QE duration (2074?±?47?ms) was longer. An earlier QE offset (2004?±?66?ms) also resulted in a large increase in the number of goals allowed (37% vs. 11%) compared to a later offset (2132?±?41?ms). Since an early, sustained QE duration contributed to a higher percentage of saves, it is important that coaches develop practice activities that challenge the goaltender's ability to fixate the puck early, as well as sustain a long QE fixation on the puck until after it is released from the stick.  相似文献   

10.
Abstract

A test of motor stage theory was conducted to screen cross-sectionally for the existence of “horizontal structure” among motor sequences within four movement components of overarm throwing and overarm striking for force. A total of 58 male subjects were filmed performing five trials of each task. Comparisons were made between movement component sequence levels as assessed by Roberton's Component Category Checklist for the Overarm Throw and Langendorfer's Component Category Checklist for Overarm Striking. Results indicated that longitudinal study of sequences within the components of trunk, humerus, forearm-racquet actions was warranted and that intertask comparisons of motor sequences were best represented by combinations of stage models proposed by Wohlwill (1973). The observed movement commonalities in the present data were consistent with constructs in both Piagetian developmental stage theory and Schmidt's schema theory in motor control and learning.  相似文献   

11.
Abstract

The present study investigated the extent to which movement time (MT) and practice influenced subjects' use of feedback to make corrections in the spatial-temporal movement pattern of coincident timing responses. Subjects performed 400 coincident timing responses of either 250,500, or 1,000 milliseconds. Schmidt's (1972) index of preprograming (IP) was used to estimate the level of feedback involvement in controlling the movement while the spatial-temporal pattern of the response was characterized by fluctuations in the speed of the movement to the barrier. The analysis of the IP and the spatial-temporal pattern of the responses suggest that MT and not practice limits the extent to which a response is preprogramed, with rapid performance more likely to be preprogramed than slower performance. Indeed, in the 1,000-millisecond response, the movement pattern appeared to be adjusted in the terminal phase (i.e., near the barrier) by accelerating or decelerating the rate of movement.  相似文献   

12.
Purpose

Previous research demonstrating that specific performance outcome goals can be achieved in different ways is functionally significant for springboard divers whose performance environment can vary extensively. This body of work raises questions about the traditional approach of balking (terminating the takeoff) by elite divers aiming to perform only identical, invariant movement patterns during practice.

Method

A 12-week training program (2 times per day; 6.5 hr per day) was implemented with 4 elite female springboard divers to encourage them to adapt movement patterns under variable takeoff conditions and complete intended dives, rather than balk.

Results

Intraindividual analyses revealed small increases in variability in the board-work component of each diver's pretraining and posttraining program reverse-dive takeoffs. No topological differences were observed between movement patterns of dives completed pretraining and posttraining. Differences were noted in the amount of movement variability under different training conditions (evidenced by higher normalized root mean square error indexes posttraining). An increase in the number of completed dives (from 78.91%–86.84% to 95.59%–99.29%) and a decrease in the frequency of balked takeoffs (from 13.16%–19.41% to 0.63%–4.41%) showed that the elite athletes were able to adapt their behaviors during the training program. These findings coincided with greater consistency in the divers' performance during practice as scored by qualified judges.

Conclusion

Results suggested that on completion of training, athletes were capable of successfully adapting their movement patterns under more varied takeoff conditions to achieve greater consistency and stability of performance outcomes.  相似文献   

13.
Abstract

The aim of this study was to test the effect that changing targets during a simple long lunge attack in fencing exerts on the temporal parameters of the reaction response, the execution speed, and the precision and the coordination of the movement pattern. Thirty fencers with more than 10 years of experience participated in this study. Two force platforms were used to record the horizontal components of the reaction forces and thereby to determine the beginning of the movement. A three-dimensional (3D) system recorded the spatial positions of the 9 markers situated on the fencer plus the epee, while a moving target was projected on a screen, enabling the control of the target change. The results indicated that when a target change is provoked the reaction time (RT), movement time (MT), and the time used in the acceleration phase of the centre of mass (CM) increases significantly with respect to the attack executed with a straight thrust. The speed and horizontal distance reached by the CM at the end of the acceleration phase (VX(CM) and SX(CM), respectively) significantly decreased, while the errors increased. However, the temporal sequence of the movement pattern did not appreciably change.  相似文献   

14.
Abstract

Previous research on the development of jumping has indicated that the coordination of the jump is stable from its inception, but that individual differences lie in the control of the task. The purpose of this study was to examine control in the vertical jump as performed by novice jumpers. Two groups of children who varied in their ability to regulate the takeoff angle were compared on measures of coordination and control. The children's groups were also compared to a group of skilled adults. Both children's groups demonstrated temporal coordination patterns comparable to the adult pattern, though the children were distinguished from the adults on selected spatial (control) measures. The results indicate that a mature pattern of coordination for the jump exists at the earliest stages of the behavior's appearance in the movement repertoire. The novice, however, lacks the ability to precisely control, or tune, the movement to task demands.  相似文献   

15.
Abstract

The aim of the present work is to examine the differences between two groups of fencers with different levels of competition, elite and medium level. The timing parameters of the response reaction have been compared together with the kinetic variables which determine the sequence of segmented participation used during the lunge with a change in target during movement. A total of 30 male sword fencers participated, 13 elite and 17 medium level. Two force platforms recorded the horizontal component of the force and the start of the movement. One system filmed the movement in 3D, recording the spatial positions of 11 markers, while another system projected a mobile target over a screen. For synchronisation, an electronic signal enabled all the systems to be started simultaneously. Among the timing parameters of the reaction response, the choice reaction time (CRT) to the target change during the lunge was measured. The results revealed differences between the groups regarding the flight time, horizontal velocity at the end of the acceleration phase, and the length of the lunge, these being higher for the elite group, as well as other variables related to the temporal sequence of movement. No significant differences have been found in the simple reaction time or in CRT. According to the literature, the CRT appears to improve with sports practice, although this factor did not differentiate the elite from medium-level fencers. The coordination of fencing movements, that is, the right technique, constitutes a factor that differentiates elite fencers from medium-level ones.  相似文献   

16.
BackgroundParticipation in physical activity supports greater cardiorespiratory fitness (CRF), a correlate of cognitive control. However, the relationship between muscular fitness (MF) and cognitive control is less clear. The present study investigated the differential relationship of CRF and MF with cognitive control in older adolescents.MethodsThis cross-sectional study involved students (15–17 years old, n = 541, 43% female) from 20 secondary schools who completed tests of inhibition (modified flanker task), working memory (n-back task), CRF (Progressive Aerobic Cardiovascular Endurance Run), and MF (standing long jump and push-up test). Multilevel analyses tested the association between CRF or MF and cognitive outcomes while accounting for the influence of the other fitness variable and relevant demographic factors.ResultsCRF predicted response accuracy during incongruent flanker trials, the condition requiring greater inhibition. For the working memory task, CRF predicted greater target accuracy and greater d'' scores on the 1-back task, requiring lesser amounts of working memory. In the 2-back task, which requires greater amounts of working memory, CRF also predicted greater target and non-target accuracy and d'' scores. Comparatively, MF did not predict any cognitive outcomes after adjustment for CRF.ConclusionCRF was selectively related to better performance during task conditions that require greater amounts of inhibition and working memory. This finding suggests that CRF, but not MF, may benefit cognitive control in older adolescents. This selective influence of CRF on older adolescents’ cognition highlights the value of aerobic physical activity.  相似文献   

17.

Writings on 'the female' under the Third Republic in France provide evidence of the profound changes taking place in the social representation of femininity and masculinity during the period. They correspond to dramatic changes in the socio-economic context in parallel with those in the scientific models being used to describe human bodily movement. This paper sets out to demonstrate both the structure of the discussion on femininity and the practice of exercise, and the possible links with changes in women's education and their social position in France. It attempts to go beyond the traditional analysis of the historical relationships between women and exercise in the period under examination (1870-1939). It reviews the debates on these relationships taking place at the time in France and within the state education system during the Third Republic and focuses on three specific aspects: work, school and society.  相似文献   

18.
Abstract

The quiet eye (QE) is a gaze phenomenon that has been studied over more than two decades. However, the underlying mechanisms of the well-known expertise effect, namely, longer QE durations in experts when compared to less-skilled athletes remain unclear. Therefore, from a functional perspective, an inhibition hypothesis was proposed that explains long QE durations in experts with increased inhibition requirements over movement parametrisation. This hypothesis was tested by making use of the especial-skill effect in basketball free throw which refers to the observation of higher actual performance than would be predicted on the basis of performance at the nearby locations. In line with the expectations, from the distance of the free-throw line, higher actual than predicted shooting accuracy and longer actual than predicted QE duration were revealed. This suggests that when performing free throws prolonged QE durations are required to shield the optimal against alternative task solutions within the very dense sub-space of this especial skill. These findings suggest an inhibition function of long QE durations in expert athletes.  相似文献   

19.
Individuals practiced two unique discrete sequence production tasks that differed in their relative time profile in either a blocked or random practice schedule. Each participant was subsequently administered a "precuing" protocol to examine the cost of initially compiling or modifying the plan for an upcoming movement's relative timing. The findings indicated that, in general, random practice facilitated the programming of the required movement timing, and this was accomplished while exhibiting greater accuracy in movement production. Participants exposed to random practice exhibited the greatest motor programming benefit, when a modification to an already prepared movement timing profile was required. When movement timing was only partially constructed prior to the imperative signal, the individuals who were trained in blocked and random practice formats accrued a similar cost to complete the programming process. These data provide additional support for the recent claim of Immink & Wright (2001) that at least some of the benefit from experience in a random as opposed to blocked training context can be localized to superior development and implementation of the motor programming process before executing the movement.  相似文献   

20.

Purpose: This exploratory study examined the notion of Seefeldt's (1980) hypothesized motor skill “proficiency barrier” related to composite levels of health-related physical fitness (HRF) in young adults. Method: A motor skill competence (MSC) index composed of maximum throwing and kicking speed and jumping distance in 187 young adults aged 18 to 25 years old was evaluated against a composite index of 5 health-related fitness (HRF) test scores. MSC (high, moderate, and low) and HRF indexes (good, fair, and poor) were categorized according to normative fitness percentile ranges. 2 separate 3-way chi-square analyses were conducted to determine the probabilities of skill predicting fitness and fitness predicting skill. Results: Most correlations among HRF and MSC variables by gender demonstrated low-to-moderate positive correlations in both men (12/15; r = .23–.58) and women (14/15; r = .21–.53). Chi-square analyses for the total sample, using composite indexes, demonstrated statistically significant predictive models, χ 2 (1, N = 187) = 66.99, p < .001, Cramer's V = .42. Only 3.1% of low-skilled (2 of 65) individuals were classified as having a “good” HRF. Only 1 participant (out of 65) who demonstrated high MSC was classified as having “poor” HRF (1.5%). Conclusion: Although individual correlations among individual MSC and HRF measures were low to moderate, these data provide indirect evidence for the possibility of a motor skill “proficiency barrier” as indicated by low composite HRF levels. This study may generate future research to address the proficiency barrier hypothesis in youth as well as adults.  相似文献   

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