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1.
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   

2.
This study examined the influence of physical exercise on the relation between shooting accuracy and the phase of the cardiac cycle in which the shot is fired. Thirteen experienced biathletes (8 females, mean age 17 years) fired from the standing position at rest and right after a submaximal exercise on a bicycle ergometer. Shooting accuracy and the timing of each shot relative to the R-waves of the electrocardiogram (ECG) were recorded. Best shots (with greatest accuracy) and worst shots (with lowest accuracy) were fired prevalently in different phases of the cardiac cycle. In the rest condition, best shots were fired less frequently from 200 to 300?ms and more frequently from 500 to 600?ms after the R-wave, compared to worst shots. In the exercise condition, best shots were fired less frequently from 100 to 200?ms after the R-wave and from 20% to 30% of the R-R interval, compared to worst shots. These findings support the hypothesis that shooting accuracy is influenced by the cardiac cycle phase due to the ballistocardiac recoil generated at each heartbeat. To achieve best results athletes could be trained (e.g. through biofeedback) to fire within a specific phase of the cardiac cycle.  相似文献   

3.
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   

4.
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   

5.
射击作为技心能为主的项目,在基本技术动作过硬的基础上,十分要求心理状态的稳定性,尤其是在新规则的实施后,更短的竞赛时间,特别是决赛阶段,可以说不允许队员有丝毫的精力分散。但是,作为＂单兵作战＂的运动项目,因赛程长、弹数多、发与发（或组与组）之间存在时间间隔,总会因为运动员的认知和情绪的变化波及后续比赛行为进而影响成绩的发挥。为了解决这一问题,射击运动员的心理技能训练被提上了日程。主要从有关射击运动员核心心理技能,即注意力控制训练出发,并始终贯穿心理咨询工作,探讨心理技能训练对射击运动员的作用与影响,结果显示通过一定的心理干预在一定程度上提高了射击运动员的竞技能力。  相似文献   

6.
Abstract

This study examined Easterbrook's (1959) hypothesis that performance on a primary task would improve or at least be maintained with increased levels of arousal, while performance on a secondary task would decrease. To test this hypothesis, the performance of 20 collegiate rifle shooters (10 experienced, 10 inexperienced) on a primary target shooting task and a secondary auditory task were compared while shooting under low- and high-time stress conditions. Heart rate results, but not a self-report anxiety measure, provided evidence for the effectiveness of the stress manipulation. The results primarily supported Easterbrook's hypothesis. There were no differences in secondary task performance between experienced and inexperienced shooters. However, subjects who first underwent high time stress followed by low (H-L) shot better than those given the reverse order (L-H). These findings are discussed in relation to the attention demands of self-paced sports as well as the transfer effects of stress.  相似文献   

7.
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   

8.
Abstract

A postural tremor appears whenever someone attempts to maintain a steady position against gravity. We examined the postural tremor that occurred while air pistol shooters were taking aim so as to compare the coordinative control of the shooters and to identify the features critical to successful shooting. Ten elite and ten pre-elite athletes participated in pistol shooting at 10 m, and the postural tremors in the pistol and upper limb were recorded with lightweight accelerometers. Exploratory analysis showed that the elite shooters had smaller tremor amplitudes than the pre-elite shooters in the pistol and distal arm segments. Compared with the pre-elite shooters, the elite shooters had a smaller tremor amplitude in the lateral direction relative to that in the vertical direction, together with weaker tremor coupling in the lateral direction and stronger vertical coupling of the pistol–hand complex. The resulting shot performance was inversely related to the amplitude of the tremor and to the 8–12 Hz spectral peak of the lateral tremor in the pistol–hand complex. We conclude that the postural tremors of air pistol shooters are associated with the skill of the shooters, and that the elite shooters could optimize the control of the pistol–hand complex, which strongly determined success in shooting.  相似文献   

9.
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   

10.
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.  相似文献   

11.
Abstract

In this study we examined the timing of optical information pick-up in basketball jump shooting using an intermittent viewing technique. We expected shooters to prefer to look at the basket as late as possible under the shooting style used. Seven experts with a high shooting style and five experts with a low shooting style took 50 jump shots while wearing liquid-crystal glasses that opened and closed at pre-set intervals. In principle, under this constraint, the participants could control when they saw the basket by actively modulating the timing of their movements. Analyses of the phasing of the movements relative to the events defined on the glasses revealed that low-style shooters preferred to see the basket just before the ball passed their line of sight, whereas high-style shooters tended to view the basket from underneath the ball after it passed their line of sight. Thus, most shooters preferred to pick up optical information as late as possible given the adopted shooting style. We conclude that, in dynamic far aiming tasks such as basketball jump shooting, late pick-up of optical information is critical for the successful guidance of movements.  相似文献   

12.
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   

13.
Abstract

Despite the importance of the Combined Event to the modern pentathlon competition, little is known about performance in the event. This study aimed to (i) identify the key variables affecting Combined Event shooting performance, and the extent to which these corresponded with those identified for precision shooting and (ii) investigate the impact of changing shooting format, and whether more successful precision shooters were also more successful in the Combined Event. Seven modern pentathletes and three pistol shooters completed precision and Combined Event trials. An opto-electronic shooting system recorded score and pistol movements, whilst force platforms recorded centre of pressure movements 1 s prior to every shot. Intra-individual analysis revealed that the extent of associations between variables was participant-specific, highlighting the need for individual analysis of performance. No participants displayed matching associations between variables for precision and Combined Event shooting, emphasising the difference between performances in the two events. Both groups experienced significantly reduced scores, and increased pistol and body movements for Combined Event shooting (P < 0.05). Despite the pistol shooters’ greater precision shooting ability, no significant differences were evident between the groups’ Combined Event performances (P > 0.05). This implies that experience in one event does not guarantee success in the other, indicating the importance of event specific training.  相似文献   

14.
In this study we examined the timing of optical information pick-up in basketball jump shooting using an intermittent viewing technique. We expected shooters to prefer to look at the basket as late as possible under the shooting style used. Seven experts with a high shooting style and five experts with a low shooting style took 50 jump shots while wearing liquid-crystal glasses that opened and closed at pre-set intervals. In principle, under this constraint, the participants could control when they saw the basket by actively modulating the timing of their movements. Analyses of the phasing of the movements relative to the events defined on the glasses revealed that low-style shooters preferred to see the basket just before the ball passed their line of sight, whereas high-style shooters tended to view the basket from underneath the ball after it passed their line of sight. Thus, most shooters preferred to pick up optical information as late as possible given the adopted shooting style. We conclude that, in dynamic far aiming tasks such as basketball jump shooting, late pick-up of optical information is critical for the successful guidance of movements.  相似文献   

15.
Postural tremor and control of the upper limb in air pistol shooters   总被引：2，自引：1，他引：1  
A postural tremor appears whenever someone attempts to maintain a steady position against gravity. We examined the postural tremor that occurred while air pistol shooters were taking aim so as to compare the coordinative control of the shooters and to identify the features critical to successful shooting. Ten elite and ten pre-elite athletes participated in pistol shooting at 10 m, and the postural tremors in the pistol and upper limb were recorded with lightweight accelerometers. Exploratory analysis showed that the elite shooters had smaller tremor amplitudes than the pre-elite shooters in the pistol and distal arm segments. Compared with the pre-elite shooters, the elite shooters had a smaller tremor amplitude in the lateral direction relative to that in the vertical direction, together with weaker tremor coupling in the lateral direction and stronger vertical coupling of the pistol-hand complex. The resulting shot performance was inversely related to the amplitude of the tremor and to the 8-12 Hz spectral peak of the lateral tremor in the pistol-hand complex. We conclude that the postural tremors of air pistol shooters are associated with the skill of the shooters, and that the elite shooters could optimize the control of the pistol-hand complex, which strongly determined success in shooting.  相似文献   

16.
Fine body movements and the cardiac cycle in archery   总被引：3，自引：1，他引：2  
This study examined the relationships between postural sway, aiming time, the cardiac cycle time and the placement of the first finger movement within the electrocardiac cycle, with the quality of the arrow shot. A small group of elite male and female archers who shot either the recurve or the compound bow, freestyle or bare bow was used in this study. A total of 240 arrows were shot, classified as being of good, average or bad quality and analysed in detail. The analyses were undertaken over two occasions up to 100 days apart. The area of postural sway, as measured by the movement of the centre of pressure coordinates, varied significantly (P less than 0.05-0.001) both within and between trials for all archers and for all quality of arrows shot. There was a tendency for the area of postural sway to increase as the quality of the arrow shot decreased. This increase in postural sway exceeded, for arrows of bad quality, that exhibited as normal postural sway when standing relaxed and addressing the target with the hands at the side. Aiming time was variable within the quality of arrow shot, although it was consistent for each archer. In some cases the aiming time increased as the quality of the arrow decreased, whereas in the case of bare bow archery the aiming time tended to decrease as the quality of the arrow deteriorated. The cardiac cycle time increased significantly (P less than 0.05-0.01) as the archers approached the loose of the good quality arrows but there was no significant increase in cardiac cycle time when arrows of average or bad quality were shot. The most consistent parameter related to the quality of the shot was the placement of the first finger movement within the ST phase or the mid-cycle phase of the electrocardiogram for arrows of good quality (P less than 0.0001).  相似文献   

17.
Abstract

Controversy surrounds the influence that caffeine has on accuracy and cognitive performance in precision activities such as shooting and archery. The aim of this study was to assess the effects of two doses of caffeine on shooting performance, reaction time, and target tracking times in the sport of clay target shooting. A randomized, double-blind, placebo-controlled design was undertaken by seven elite male shooters from the double-trap discipline. Three intervention trials (2 mg caffeine · kg?1 body mass (BM); 4 mg caffeine · kg?1 BM; placebo) were undertaken, in which shooters completed four rounds per trial of 50 targets per round. Performance accuracy (score) and digital video footage (for determination of reaction time and target tracking times) were gathered during competition. Data were analysed using repeated-measures analysis of variance. No differences in shooting accuracy, reaction time or target tracking times among the three intervention trials or across the four rounds within each intervention were observed (P > 0.05). The results indicate that ingestion of ≤4 mg caffeine · kg?1 BM does not provide performance benefits to elite performers of clay target shooting in the double-trap discipline.  相似文献   

18.
The purpose of this study was to examine the three-dimensional movement profile of the blade during a stationary slap shot, as a function of player skill level. A total of 15 subjects participated; eight were classified as elite and the remaining seven were recreational. Performances were evaluated by simultaneously recording the movements of the stick’s lower shaft and blade with high-speed video (1000 Hz), the time of stick-ground contact with two uniaxial forceplates and time of blade-puck contact with a uniaxial accelerometer mounted within the puck. Data were analysed with a two-way MANOVA for several dependent variables including linear kinematics, temporal phase data and global angles. The results indicated that skill level affected blade kinematics, with elite shooters tending to alter timing parameters (i.e. phase length), magnitude of linear variables (i.e. displacement, etc.) and the overall blade orientation to achieve a higher velocity slap shot. These analyses identified a unique ‘rocker’ phase within the execution of the slap shot in both groups.  相似文献   

19.
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   

20.
The combined event is a crucial aspect of the modern pentathlon competition, but little is known about how shooting performance changes through the event. This study aimed to identify (i) how performance-related variables changed within each shooting series and (ii) how performance-related variables changed between each shooting series. Seventeen modern pentathletes completed combined event trials. An optoelectronic shooting system recorded score and pistol movement, and force platforms recorded centre of pressure movement 1 s prior to every shot. Heart rate and blood lactate values were recorded throughout the event. Whilst heart rate and blood lactate significantly increased between series (P < 0.05), there were no accompanying changes in the time period that participants spent aiming at the target, shot score, pistol movement or centre of pressure movement (P > 0.05). Thus, combined event shooting performance following each running phase appears similar to shooting performance following only 20 m of running. This finding has potential implications for the way in which modern pentathletes train for combined event shooting, and highlights the need for modern pentathletes to establish new methods with which to enhance shooting accuracy.  相似文献   

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