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1.
This study examined the effects of length and movements of preshot routines on free throw shooting in basketball. 17 members of an intercollegiate men's basketball team attempted 20 free throws in each of four different conditions: (1) normal routine and time, (2) normal routine with altered time, (3) altered routine with normal time, and (4) altered routine with altered time. Free throw performance was measured using an objective 5-point scoring system. A multivariate analysis of variance indicated a significant effect for routine. Neither time nor routine by time was significant. Results indicated that altering the movements in the routine had a significant effect on performance while lengthening the time did not.  相似文献   

2.
The purpose of the present study was to analyze the movement patterns of free-throw shooters in basketball at different skill levels. There were two points of interest. First, to explore what information can be drawn from the movement pattern and second, to examine the methodological possibilities of pattern analysis. To this end, several qualitative and quantitative methods were employed. The resulting data were converged in a triangulation. Using a special kind of ANN named Dynamically Controlled Networks (DyCoN), a 'complex feature' consisting of several isolated features (angle displacements and velocities of the articulations of the kinematic chain) was calculated. This 'complex feature' was displayed by a trajectory combining several neurons of the network, reflecting the devolution of the twelve angle measures over the time course of each shooting action. In further network analyses individual characteristics were detected, as well as movement phases. Throwing patterns were successfully classified and the stability and variability of the realized pattern were established. The movement patterns found were clearly individually shaped as well as formed by the skill level. The triangulation confirmed the individual movement organizations. Finally, a high stability of the network methods was documented.  相似文献   

3.
Participants performed a free-throw shooting task and a grip-strength task before and after imagery, nonspecific arousal, or no instructions. Imagery improved performance in the free-throw shooting task, which is assumed to have more cognitive components than the grip-strength task. Imagery did not improve performance in the grip-strength task, which is assumed to have fewer cognitive components than the free-throw task. Nonspecific arousal, on the other hand, improved performance in the grip-strength task but not in the free-throw shooting task. Athletic experience, confidence levels, and gender were correlated with actual performance levels in both tasks, but not with improvement. Results are discussed within the transfer-appropriate processing framework.  相似文献   

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The objective of this study was to investigate the coordination of a whole-body task (basketball free-throw) in which success in performance outcome can be achieved through a manifold of combinations of postural and movement trajectory configurations. Participants were healthy men (19–24 years) with a range of skill levels that were tested for the accuracy of 50 basketball free-throws with both their dominant and non-dominant hand. The trial-to-trial variance in release parameters as well as postural stability of the shooter and synchronization of postural movement and ball release were strong predictors of performance, with non-elite shooters having a higher mean and variability of center-of-mass (COM) speed at the time of ball release. The synchronization between the time of peak COM and the time of ball release increased as a function of skill level and hand dominance, with the better performers releasing the ball more closely to the time of COM peak height. These findings reveal how, in addition to successfully controlling the trial-to-trial variability along the solution manifold of release parameters, the relative importance of the coordination of postural control and ball release properties on shooting success changes as a function of skill level.  相似文献   

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This study empirically assessed the effect weight training has on the accuracy of free-throw shots immediately following a weight-training session. On On alternating days of the week for eight weeks, 14 members of a women's varsity intercollegiate basketball team engaged in a weight-training program and an aerobics exercise program. Each day immediately following the conditioning, the players shot two sets of 10 free throws. Analysis indicated no significant difference in free-throw shooting accuracy as a function of weight training when compared to the aerobic exercise, suggesting that the immediate effects of weight training are no more detrimental or beneficial for free-throw shooting than aerobic exercise.  相似文献   

8.
The aim of this study was to clarify the strategy used by basketball players during free-throw shooting to improve performance in the presence of motor noise. Two possible hypotheses were examined: the players minimize the release speed to decrease signal-dependent noise or the players maximize the shot success probability by accounting for their variability. Eight collegiate players and one professional player participated in this study by attempting shots from the free-throw line using a motion capture system. The solution manifold consisting of ball parameters at release was calculated and the optimal strategy was simulated by considering ball parameter variability; this result was compared with the actual data. Our results showed that participants selected the solution of near-minimum release speed. The deviation of the measured release angle from the minimum-speed angle was close to zero (2.8 ± 3.1). However, an increase in speed-dependent noise did not have a significant influence on the ball landing position through simulation. Additionally, the effect of release angle error on the ball landing position was minimum when using the minimum speed strategy. Therefore, the players minimize the release speed to minimize the effect of the release error on performance, instead of minimizing the speed-dependent noise itself. In other words, the strategy is “near-minimum-speed strategy” as well as “minimum-error-propagation strategy”. These findings will be important for understanding how sports experts deal with intrinsic noise to improve performance.  相似文献   

9.
Observational learning has long been used to instruct individuals on how to perform a novice motor skill. Recently, research has shown a benefit to instructing learners to focus externally when viewing a video model (Asadi, Aiken, Heidari, & Kochackpour, 2021). Research has also highlighted the effectiveness of modeling correct gaze behaviors when learning a cognitive task (Jarodzka, van Gog, Dorr, Scheiter, & Gerjets, 2013). The purpose of the present study was to investigate the effectiveness of combining these two modalities. 40 individuals with a mean age of 21.77 ± 1.40 performed a novel motor task where they were asked to either focus internally or externally, and were provided with traditional instruction or were provided with an experienced performer's gaze behaviors while viewing a video demonstration. It was observed that both the external focus groups and the gaze instructed groups performed a basketball free-throw more accurately and had longer periods of quiet eye than an internal focus or traditional verbal instruction (p's < 0.05). Eye tracking also allowed for the assessment of attentional focus adherence. Participants focused on the instructed cues significantly more than irrelevant task aspects or a different focus types (p's < 0.05). These results highlight the effectiveness of cuing a learner to focus externally during observational learning. It also highlights the usefulness of providing correct gaze behaviors when observing a model.  相似文献   

10.
The purpose of this analysis of data from a larger investigation was to assess effects of anthropometric factors on free throw shooting performance of 15 girls from Michigan and 18 from Puerto Rico. Subjects performed 60 free throws (10 trials x 3 ball sizes x 2 basket heights). Correlations were low, with two exceptions, .53 between shooting performance at the low basket and grip strength (as measured by hand grip dynamometer) for girls from Michigan, and .49 for hand width and performance at the low basket for girls from Michigan.  相似文献   

11.
Abstract

The current pilot study aimed at providing an initial assessment of how anxiety influences police officers’ shooting behavior. Seven police officers participated and completed an identical shooting exercise under two experimental conditions: low anxiety, against a non-threatening opponent, and high anxiety (HA), against a threatening opponent who occasionally shot back using colored soap cartridges. Measurements included shooting accuracy, movement times, head/body orientation, and blink behavior. Results showed that under HA, shooting accuracy decreased. Underlying this degradation of performance, participants acted faster and made themselves smaller to reduce the chance of being hit. Furthermore, they blinked more often, leading to increases in the amount of time participants had their eyes closed. Findings provide support for attentional control theory, hereby also pointing to possible interventions to improve police officers’ shooting performance under pressure.  相似文献   

12.
Two experiments address the accuracy of citizen and police witnesses in recalling stressful events. Participants saw 2 training scenarios. Experiment 1 evaluated the effects of active engagement and the presence of a simulated shooting on police officers' memory for details. Police officers recalled significantly fewer details from the scenario in which a shooting occurred. Active engagement did not influence recall. Experiment 2 compared the memory performance of police and citizen witnesses. Manipulation checks were added to assess the arousal produced by a shooting, and control procedures were added to evaluate the memorability of specific scenarios. Police and citizen witnesses did not differ reliably in accuracy. The perpetrator was remembered less well than the weapon when a simulated shooting occurred, and one scenario was significantly more difficult to remember than the other. The need to replicate eyewitness research with a variety of materials is discussed.  相似文献   

13.
Emergency medical workers’ distress and recovery patterns after a mass shooting were related to their coping behaviors and routine daily activities. This longitudinal repeated measures study assessed 31 emergency medical workers’ psychological and psychosomatic symptoms self-rated for the weeks before, those just after, and one full month after the shooting. Coping behaviors and time in creative activities were related to increased acute distress; recovery was related to more time in constructive activities. Thinking about the incident was related to higher acute distress but better recovery on several SCL9OR scales. Exercise predicted recovery on Obsessive-Compulsive and Hostility scales. Studies evaluating emergency workers’ reactions to and recovery from critical incidents should use repeated measures designs, should assess short-term recovery, and should distinguish among symptoms.  相似文献   

14.
Emergency medical workers’ distress and recovery patterns after a mass shooting were related to their coping behaviors and routine daily activities. This longitudinal repeated measures study assessed 31 emergency medical workers’ psychological and psychosomatic symptoms self-rated for the weeks before, those just after, and one full month after the shooting. Coping behaviors and time in creative activities were related to increased acute distress; recovery was related to more time in constructive activities. Thinking about the incident was related to higher acute distress but better recovery on several SCL9OR scales. Exercise predicted recovery on Obsessive-Compulsive and Hostility scales. Studies evaluating emergency workers’ reactions to and recovery from critical incidents should use repeated measures designs, should assess short-term recovery, and should distinguish among symptoms.  相似文献   

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The aim of this study was to test the hypothesis that a combined relaxation (applied tension release, ATR) and specific shooting training regimen may enhance shooting ability of biathlon athletes. Seven biathletes of high national level were randomized into an experimental group (age 20 ± 5 years; Vo2max 60 ± 8 mL kg(-1) min(-1)) and were asked to add this special training intervention to their regular training for 10 weeks, while five other biathletes served as controls (age 19 ± 2 years; Vo2max 57 ± 10 mL kg(-1) min(-1)). The shooting ability of the subjects was assessed before and after the intervention at rest and after roller skiing on a treadmill in a laboratory-based competition simulating assessment. After the intervention period, the experimental group demonstrated a significantly enhanced shooting performance compared to the control group. No changes in Vo2max or in heart rate and Vo2 responses were observed before and after the intervention in either group and there were no differences between the groups in these parameters. Thus, the preliminary conclusion is that a combination of ATR and specific shooting training seems to be instrumental in enhancing the shooting performance in biathlon.  相似文献   

17.
Reports suggest that individuals with developmental disabilities often engage in behavior during dental visits that precludes regular dental care. Graduated exposure therapies are an effective treatment for avoidant behavior in people with developmental delays, and some studies show that the duration of the intersession interval (ISI) can impact the effectiveness of graduated exposure treatments for typically developing individuals. The current study examined the effects of decreasing ISI on outcomes of a graduated exposure treatment during simulated routine dental care for 3 individuals diagnosed with autism. Treatment consisted of graduated exposure and extinction for disruptive behavior. Initially, sessions were conducted once per week. In subsequent conditions, treatment sessions were conducted 3‐5 times per week. A nonconcurrent multiple baseline across subjects design was used to demonstrate experimental control. Results suggest that decreasing ISI durations can produce improved treatment outcomes.  相似文献   

18.
During professional shooting tournaments, which typically last multiple hours, athletes must stay focused at all times in order to perform at their highest levels. Sustaining attention over extended periods of time relies on self-control. Crucially, perceived state self-control strength appears to wane as a function of task duration, which ultimately can impair shooting performance. In the present study, we tested the assumption that the level of self-reported self-control strength decreases over the course of a 1-h shooting task measured twice during a regular training day and separated by a 2-h break. Additionally, we assumed that shooting performance would be linked with fluctuations in self-control. A total of 21 shooters (14 elite and 7 sub-elite) took part in this study and were asked to perform a series of 10 shots at a standardized target, five times in the morning and five times in the afternoon (i.e., 100 shots total). The participants also reported their perceived state self-control strength at the baseline (prior to the start of the morning session as well as the afternoon session) and after a series of 10 shots each in the morning and afternoon (i.e., 12 measurements in total). In line with our hypotheses, we observed that perceived state self-control diminished with the number of shots performed, and that perceived state self-control could explain shooting performance. Additionally, these observations could explain the difference in shooting performance between elite and sub-elite athletes. The results suggest that the perception of self-control strength is highly important for optimal shooting performance. Practical implications are discussed.  相似文献   

19.
20.
Basketball jump shooting is controlled online by vision   总被引:1,自引:0,他引:1  
An experiment was conducted to examine whether basketball jump shooting relies on online visual (i.e., dorsal stream-mediated) control rather than motor preprogramming. Seventeen expert basketball players (eight males and nine females) performed jump shots under normal vision and in three conditions in which movement initiation was delayed by zero, one, or two seconds relative to viewing the basket. Shots were evaluated in terms of both outcome and execution measures. Even though most shots still landed near the basket in the absence of vision, end-point accuracy was significantly better under normal visual conditions than under the delay conditions, where players tended to undershoot the basket. In addition, an overall decrease of inter-joint coordination strength and stability was found as a function of visual condition. Although these results do not exclude a role of motor preprogramming, they demonstrate that visual sensory information plays an important role in the continuous guidance of the basketball jump shot.  相似文献   

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