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1.
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.  相似文献   

2.
This study was designed to examine whether participants who could control the schedule of performance feedback (KP) would learn differentially from those who received a rigid feedback schedule while learning a complex task. Participants (N = 48) were randomly assigned to self-controlled KP (SELF), summary KP (SUMMARY), yoked control (YOKE), or knowledge of results only (KR) conditions. Data collection consisted of an acquisition phase and a 4-day retention phase during which right-handed participants performed a left-handed ball throw. Overall, throwing form improved across trial blocks during acquisition, with the SUMMARY, SELF, and YOKE groups showing more improvement than the KR group. During retention, the SELF group retained a higher level of throwing form and accuracy in comparison to the other groups. Results suggest that when given the opportunity to control the feedback environment, learners require relatively less feedback to acquire skills and retain those skills at a level equivalent to or surpassing those who are given more feedback but receive it passively.  相似文献   

3.
以篮球项目中的基础技术原地单手肩上投篮为测试技能,探讨不同相对频率操作反馈(以下简称KP)对该技能学习绩效的影响。将56名体育学院右利手大学一年级男生随机分配到33%KP组、100%KP组、渐减KP组和控制组当中,每组14人。分别在4种不同的KP控制条件下练习投篮技能,每天练习30次。在练习期间教师按照实验控制条件,并依据原地单手肩上投篮动作的易犯错误分别为各组被试提供恰当的言语反馈。在第3天全部练习结束后休息3 min,进行无KP学习阶段测试,24 h之后再进行无KP保持阶段测试。实验结果显示:(1)学习阶段100%KP组的绩效明显优于33%KP组和渐减KP组;而在24 h保持阶段这种趋势发生了逆转,即33%KP组和渐减KP组的绩效明显优于100%KP组;(2)渐减KP组与33%KP组绩效未出现显著性差异;(3)不同相对频率KP组绩效优于控制组。  相似文献   

4.
Abstract

This study examined the effects of knowledge of results (KR) delay and subjective estimation of movement form on the acquisition and retention of a motor skill. During acquisition, four groups of participants performed 60 trials of a throwing accuracy task under the following conditions: (a) immediate KR, (b) delayed KR, (c) immediate KR + form estimation, and (d) delayed KR + form estimation. Retention tests of throwing accuracy and outcome error estimation in the absence of visual KR were administered 5 min and 24 hours following acquisition. Throwing accuracy was significantly higher during acquisition but significantly lower during retention for immediate-KR participants than for delayed-KR participants. However, participants who estimated their movement form during acquisition produced significantly higher throwing accuracy and lower estimation error during retention than those who did not.  相似文献   

5.
The aim of the study was to evaluate the effect of maximal specific physical effort on postural balance and rifle stability in biathletes in a standing shooting position. The study included 10 junior elite biathletes. The measurements were taken with the Vicon system and AMTI force platform. Postural balance and rifle stability characteristics were determined at rest as well as 1 and 5 min post maximal specific physical effort which was performed on a ski ergometer and continued until exhaustion. Maximal physical effort exerted a significant effect on all examined postural sway and rifle sway characteristics. The duration of the post-exercise changes was longer than 5 minutes. Higher post-effort rifle sway was observed in the vertical direction than in the across the shooting line direction. Post-effort postural balance impairment in the shooting line was much greater than in the across the shooting line direction. Moreover, a strong correlation was found between postural balance and rifle stability. Maximal physical effort influenced postural balance and rifle stability during aiming. Rifle sway during aiming in a standing shooting position seems to be coordinated with the postural sway of the biathlete’s body. Thus, an increase in postural sway contributes to greater sway and lesser stability of the rifle.  相似文献   

6.
Abstract

This study investigated the timing of the trigger pull in relation to the cardiac cycle during air rifle shooting. Electrocardiogram) was recorded from 20 male nonelite rifle shooters in two separate testing sessions. The testing was conducted at an indoor shooting range using an optoelectronic shooting system. Each participant fired a shot in the standing position at a distance of 10 m from the target. The results showed that compared to random triggering, the shooters fired more often during the phase of 10–50% of the R wave-to-R wave (R-R) interval and less often during the phase of 50–90%. With regard to performance accuracy, the participants exhibited average or above average performance, when the shot occurred in the beginning (0–50%) and in the end (70–99%) of the R-R interval. The less optimal range for the triggering was located within the 50–70% phase of the R-R interval. The length of R-R interval (i.e., heart rate) did not affect the relation of shot placement within the cardiac cycle to the accuracy of shooting performance. The present results extend previous findings by showing that in air rifle shooting the optimum firing time within the cardiac cycle may be located in the systolic phase. It is argued that the systole-diastole dichotomy is not a sufficiently accurate way to investigate the effects of shot placement in the cardiac cycle. Further research is needed to examine the extent to which the relationship between the timing of triggering within the cardiac cycle and shooting performance depends a shooter's skill level.  相似文献   

7.
步枪训练在射击比赛中稳定性是基础,心理稳定是关键。在射击比赛中决定胜负往往取决于稳定性因素。笔者阐述了步枪射击稳定性的内容、要求和大赛实战意义,同时提出了加强步枪射击稳定性的训练途径。1）射击训练是基础,心理是关键;2）科训结合可为训练提供大量数据;3）做好赛前准备是取胜的基础;4）善于处理矛盾,稳定运动员思想,是取胜的基本保障。  相似文献   

8.
ABSTRACT

Purpose: This study aimed to examine the effect of gradual self-control of task difficulty and feedback on accuracy and movement pattern of the golf putting sport skill. Method: Sixty students were quasi-randomly assigned to four groups under a varying combination of the two factors of task difficulty control (self-controlled or yoked) and feedback control (self-controlled or yoked). The participants in the two groups (dual-factor gradual self-control and self-controlled task difficulty group) that granted control over task difficulty in the acquisition phase were told they could choose any of the pre-set distances from the target. All groups were given 100% feedback in the first half of the acquisition phase, but the participants in the two groups (dual-factor gradual self-control group and self-controlled feedback) that could control their feedback were told that in the second half of the acquisition phase they would be able to ask for feedback when needed. The practice schedule of each member of the dual-factor gradual self-control group was used as a basis to plan the practice of predetermined distances and feedback presentation to the corresponding participants in the yoked conditions. Results: ANOVA with repeated measures showed that the practice method involving gradual self-control of two factors had a positive impact on accuracy and movement pattern of golf putting in the retention and transfer tests compared to other methods (ps < .05). Conclusion: The advantages of self-control practice presumably come from better adjustment of challenge points by the learner in the course of the practice.  相似文献   

9.
This study investigated the timing of the trigger pull in relation to the cardiac cycle during air rifle shooting. Electrocardiogram) was recorded from 20 male nonelite rifle shooters in two separate testing sessions. The testing was conducted at an indoor shooting range using an optoelectronic shooting system. Each participant fired a shot in the standing position at a distance of 10 m from the target. The results showed that compared to random triggering, the shooters fired more often during the phase of 10-50% of the R wave-to-R wave (R-R) interval and less often during the phase of 50-90%. With regard to performance accuracy, the participants exhibited average or above average performance, when the shot occurred in the beginning (0-50%) and in the end (70-99%) of the R-R interval. The less optimal range for the triggering was located within the 50-70% phase of the R-R interval. The length of R-R interval (i.e., heart rate) did not affect the relation of shot placement within the cardiac cycle to the accuracy of shooting performance. The present results extend previous findings by showing that in air rile shooting the optimum firing time within the cardiac cycle may be located in the systolic phase. It is argued that the systole-diastole dichotomy is not a sufficiently accurate way to investigate the effects of shot placement in the cardiac cycle. Further research is needed to examine the extent to which the relationship between the timing of triggering within the cardiac cycle and shooting performance depends a shooter's skill level.  相似文献   

10.
采用键盘敲击任务探讨学习者主观估计错误活动、结果反馈时机(knowledge of results,简称KR)对运动技能学习的影响.抽取90名右利手的在校大学生,随机分为:主观估计无KR组、主观估计及时KR组、主观估计延迟KR组,算术活动无KR组,算术活动及时KR组,算术活动延迟KR组(组间性别均衡设计).主观估计错误活动组在练习间以口头报告的形式评估自己刚才操作总时间的误差,算术活动组按照实验员的要求进行数字算术口头运算.无KR组不提供KR,及时KR组在主观估计错误活动或算术活动后即刻获得KR,延迟KR组则延迟4s获得KR.第1-2天,6组受试者在各自的条件下分别练习,每天练习108次.第3天,练习后,休息10min,使用原任务进行保持测试10次,要求受试者每次测试后口头报告自己操作的总时间.第4天,使用原任务进行保持测试10次,要求受试者每次测试后口头报告自己操作的总时间.结果显示:(1)练习后从事主观估计错误活动,并能及时获得KR的学习者,保持测试的绩效最好;(2)主观估计错误活动影响提供KR的适宜时机.  相似文献   

11.
The present experiment examined the learning effects of participants self-controlling their receipt of knowledge of results (KR) on all or half of their acquisition trials (50%). For participants who were provided 50% self-control, the first half of their acquisition period consisted of receiving KR on all trials, or according to a faded-KR schedule. Participants practiced a sequential timing task. The results showed that independent of practice condition, participants who self-controlled their KR during the acquisition period demonstrated superior performance compared to the respective yoked conditions in the retention and transfer portion of the experiment. These results extend previous research by suggesting that decreasing the proportion of self-control trials does not compromise learning in a self-controlled context.  相似文献   

12.
Abstract

We conducted two experiments to assess the effect attentional focus has on learning a complex motor skill and subsequent performance under secondary task loading. Participants in Experiment 1 learnt a golf putting task (300 practice trials) with a single instruction to either focus on their hands (internal focus) or the movement of the putter (external focus). No group differences were evident during learning or retention. Differences between the groups were only apparent under secondary task load; the external group's performance remained robust, while the internal group suffered a drop in performance. Verbal protocols demonstrated that the internal group accumulated significantly more internal knowledge and more task-relevant knowledge in general than the external group. Experiment 2 was designed to establish whether greater internal focus knowledge or greater explicit rule build up in general was responsible for performance breakdown. Two groups were presented with a set of six internal or external rules. Again, no performance differences were found during learning or retention. During the secondary task, both groups experienced performance deterioration. It was concluded that accumulation of explicit rules to guide performance was responsible for the internal group's breakdown in performance under secondary task loading and may be responsible for some of the performance differences reported previously.  相似文献   

13.
理论研究薄弱是我国开展雪上项目的主要掣肘因素,也制约了我国对2022北京冬奥会的备战。本研究从运动员生物学特征、比赛技术及训练角度分析了冬季两项的项目特征,认为形态学的主要特征为身体强壮、体脂率低,运动员在滑行和射击中的主要生理指标特征分别为较高的HR、VO2max、乳酸阈值与机体总工作效率,及良好的身体感知与自我调节能力,运动损伤特征为日常训练多发,女性与7年以上运动员多发,下背部与膝部多发。技术特征方面,滑行中自由滑行技术的G2和G3分技术对成绩影响最大,ML站姿更利于射击中维持身体稳定性,而肩上夹紧枪托及较轻的双手持枪力度更利于持枪稳定性和射击准度。年度体能训练以LIT为主,MIT与HIT比例较低;陆地体能训练中滚轮滑雪比例最高,辅以较高比例蹬车训练,雪上训练以自由滑行G2、G3分技术练习为主;力量训练中,男运动员侧重均衡的上、下肢练习,女运动员侧重上肢力量训练;射击训练多采取分组竞争、模拟比赛的方式进行,并注重训练大风天气下的适应力。  相似文献   

14.
In this study, we examined the relationships between body sway, aim point fluctuation and performance in rifle shooting on an inter- and intra-individual basis. Six elite shooters performed 20 shots under competition conditions. For each shot, body sway parameters and four aim point fluctuation parameters were quantified for the time periods 5 s to shot, 3 s to shot and 1 s to shot. Three parameters were used to indicate performance. An AMTI LG6-4 force plate was used to measure body sway parameters, while a SCATT shooting analysis system was used to measure aim point fluctuation and shooting performance. Multiple regression analysis indicated that body sway was related to performance for four shooters. Also, body sway was related to aim point fluctuation for all shooters. These relationships were specific to the individual, with the strength of association, parameters of importance and time period of importance different for different shooters. Correlation analysis of significant regressions indicated that, as body sway increased, performance decreased and aim point fluctuation increased for most relationships. We conclude that body sway and aim point fluctuation are important in elite rifle shooting and performance errors are highly individual-specific at this standard. Individual analysis should be a priority when examining elite sports performance.  相似文献   

15.
The purpose of this study was to identify joint angular kinematics that corresponds to shooting accuracy in the stationary ice hockey wrist shot. Twenty-four subjects participated in this study, each performing 10 successful shots on four shooting targets. An eight-camera infra-red motion capture system (240 Hz), along with passive reflective markers, was used to record motion of the joints, hockey stick, and puck throughout the performance of the wrist shot. A multiple regression analysis was carried out to examine whole-body kinematic variables with accuracy scores as the dependent variable. Significant accuracy predictors were identified in the lower limbs, torso and upper limbs. Interpretation of the kinematics suggests that characteristics such as a better stability of the base of support, momentum cancellation, proper trunk orientation and a more dynamic control of the lead arm throughout the wrist shot movement are presented as predictors for the accuracy outcome. These findings are substantial as they not only provide a framework for further analysis of motor control strategies using tools for accurate projection of objects, but more tangibly they may provide a comprehensive evidence-based guide to coaches and athletes for planned training to improve performance.  相似文献   

16.
In this study, we examined the relationships between body sway, aim point fluctuation and performance in rifle shooting on an inter- and intra-individual basis. Six elite shooters performed 20 shots under competition conditions. For each shot, body sway parameters and four aim point fluctuation parameters were quantified for the time periods 5 s to shot, 3 s to shot and 1 s to shot. Three parameters were used to indicate performance. An AMTI LG6-4 force plate was used to measure body sway parameters, while a SCATT shooting analysis system was used to measure aim point fluctuation and shooting performance. Multiple regression analysis indicated that body sway was related to performance for four shooters. Also, body sway was related to aim point fluctuation for all shooters. These relationships were specific to the individual, with the strength of association, parameters of importance and time period of importance different for different shooters. Correlation analysis of significant regressions indicated that, as body sway increased, performance decreased and aim point fluctuation increased for most relationships. We conclude that body sway and aim point fluctuation are important in elite rifle shooting and performance errors are highly individual-specific at this standard. Individual analysis should be a priority when examining elite sports performance.  相似文献   

17.
Abstract

The effects of stance angle on postural stability and shooting processes were studied using eight national-standard male air-pistol shooters. Each shooter performed 60 shots each in four stance angles (0°, 15°, 30° and 45° from the line of fire). Postural stability was determined by measuring change in centre of pressure with a dual-force platform system assessing centre-of-pressure (COP) excursion (average difference of the centre of pressure from the mean) and COP speed (total COP path divided by time). Shooting process measures were determined by using a NOPTEL ST-2000 optoelectronic system. Score was assessed with a Sius Ascor S10 electronic scoring system. The results revealed no significant difference among the various stance angles; COP excursion or COP speed, p>0.05. Results indicated a significant stance angle effect with the shooting process measure, hit fine (percentage of hold within an area the size of the 10-ring when centred over the actual shot; p = 0.025) and the shooting performance measure adjusted score (raw score adjusted for true zero; p=0.008). Moreover, best overall performance was with a stance angle of 15°. These findings suggest that stance angle may affect pistol stability and performance in air-pistol athletes.  相似文献   

18.
任务性质、结果反馈时机与运动技能的学习   总被引：1，自引：0，他引：1  
采用键盘敲击任务探讨任务性质、结果反馈时机对运动技能学习的影响.将100名右优势手大学生随机分为开放性和封闭性任务组(男女各25名),两组分别在5种KR条件下,练习开放或封闭任务3天,每天练习108次.第3天练习结束后休息10min,进行不提供KR的保持测试10次.24 h后,进行无KR保持测试10次.结果显示:(1)在封闭性运动技能学习中延迟KR更有利,而即刻KR促进开放性运动技能的学习;(2)提供KR的适宜时机受任务性质影响.与开放性技能相比,操作封闭性技能时,提供KR的适宜时机应延迟.  相似文献   

19.
Abstract

The purpose of this study was to examine the variability in cortical activation during physical air-rifle shooting and three different observation conditions. Elite air-rifle shooters performed a 40 shot individual match. Electroencephalograms were recorded from 11 active sites across the cortex during the final 6 s (3 × 2 s epochs) before shot release. Data collection was repeated while shooters watched a large-screen video of their worst shot performance from an internal-visual perspective when seated, standing and standing holding their rifle. The hypothesized differences between the three observation conditions and the physical shooting profile were not shown except at the left anterior temporal site, T5. This finding suggests that observation of performance cannot be differentiated clearly by posture or modified through kinetic and haptic afference, and that visual percepts predominate in observational functional equivalence. However, more functionally equivalent observation reduced the observation/execution variability over the temporal areas. Performer debriefs also identified different perceptions of physiological, psychological and behavioural functional equivalence associated with the different observation conditions. We conclude that elite performers' brains are accessed equally effectively during different observation conditions irrespective of some of the physical factors ascribed to the conditions. However, they may require more functionally matched conditions to attain greater equivalence in temporal areas.  相似文献   

20.
The purpose of this study was to examine the variability in cortical activation during physical air-rifle shooting and three different observation conditions. Elite air-rifle shooters performed a 40 shot individual match. Electroencephalograms were recorded from 11 active sites across the cortex during the final 6 s (3 x 2 s epochs) before shot release. Data collection was repeated while shooters watched a large-screen video of their worst shot performance from an internal-visual perspective when seated, standing and standing holding their rifle. The hypothesized differences between the three observation conditions and the physical shooting profile were not shown except at the left anterior temporal site, T5. This finding suggests that observation of performance cannot be differentiated clearly by posture or modified through kinetic and haptic afference, and that visual percepts predominate in observational functional equivalence. However, more functionally equivalent observation reduced the observation/execution variability over the temporal areas. Performer debriefs also identified different perceptions of physiological, psychological and behavioural functional equivalence associated with the different observation conditions. We conclude that elite performers' brains are accessed equally effectively during different observation conditions irrespective of some of the physical factors ascribed to the conditions. However, they may require more functionally matched conditions to attain greater equivalence in temporal areas.  相似文献   

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