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1.
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   

2.
Purpose

This study investigated whether within-task expertise affects the reported asymmetry in execution time exhibited in reactive and self-initiated movements.

Method

Karate practitioners and no-karate practitioners were compared performing a reverse punch in reaction to an external stimulus or following the intention to produce a response (self-initiated). The task was completed following the presentation of a specific (i.e., life-size image of opponent) or general stimulus and in the presence of click trains or white noise.

Results

Kinematic analyses indicated reactive movement had shorter time to peak velocity and movement time, as well as greater accuracy than self-initiated movement. These differences were independent of participant skill level although peak velocity was higher in the karate practice group than in the no-karate practice group. Reaction time (RT) of skilled participants was facilitated by a specific stimulus. There was no effect on RT or kinematic variables of the different type of auditory cues.

Conclusions

The results of this study indicate that asymmetry in execution time of reactive and self-initiated movement holds irrespective of within-task expertise and stimulus specificity. This could have implications for training of sports and/or relearning of tasks that require rapid and accurate movements to intercept/contact a target.  相似文献   

3.
Abstract

This study investigated stimulus velocity effect on manual asymmetry during planning and execution of a complex coincidence-anticipation task. Left- and right-handers were required to press six buttons sequentially in conjunction with visual stimulus provided by a coincidence-anticipation device. Results showed that (1) stimulus velocity affected timing response and timing accuracy only for right-handers, who responded faster but less accurately in the fast stimulus velocity, (2) manual asymmetries for both handedness groups revealed a left-hand advantage for initiating the movement, and a preferred-hand advantage for movement time. The preferred-hand advantage in timing accuracy was only observed in the fast stimulus velocity. These findings are discussed in the framework of the hemispheric functional lateralisation.  相似文献   

4.
The present study evaluated the role of compatibility effects in the precuing of arm and direction parameters. In the first two experiments different stimulus and response arrangements were examined. For all three experiments the spatial precue and imperative stimuli were compatibly assigned to responses (i.e., a direct correspondence existed between the stimulus and response locations). Experiments 1 and 2 indirectly tested the effect of decision processes required by the stimulus-response set. Experiment 1 replicated previous research that has found longer reaction times for the direction uncertain parameter as compared to arm uncertain. Experiment 2 examined the precuing of arm and direction parameters with stimuli that maintained right-left arrangements for both parameters. Unlike Experiment 1, reaction times did not differ for precuing the two movement parameters. Experiment 3 directly examined the effect of differential decision requirements from up-down spatial stimuli and right-left spatial stimuli for a single parameter. In support of results from the first two experiments, results indicated longer reaction times for decisions from up-down stimuli as compared to right-left stimuli. Because reaction times for precued movement parameters are a function of the stimulus and response arrangements used, differences in reaction times are most likely due to compatibility effects arising from differences in the spatial arrangements of the precued stimulus and response set.  相似文献   

5.
Abstract

Research examining the proximal-to-distal sequencing of segments of the body involved in overarm throwing has been equivocal: some studies have found support for the concept while others have not. The aim of the present study, therefore, was to determine if there is a proximal-to-distal sequence in the timing of the movements of joints and the distal endpoints of segments in overarm throwing. The three-dimensional kinematics of a penalty throw in experienced team handball players (n = 11) were recorded and analysed with regard to the timing of events. We analysed the timing of the maximal velocity of the distal endpoints of six segments and the maximal angular velocity in 11 joints, as well as the initiation of these joint movements. A temporal proximal-to-distal sequence was observed only for the initiation of the joint movements. No such sequence was found for maximal velocity of the joints and distal endpoints of segments.  相似文献   

6.
Background:Proprioceptive accuracy refers to the individual’ s ability to perceive proprioceptive information,that is,the information referring to the actual state of the locomotor system,which originates from mechanoreceptors located in various parts of the locomotor system and from tactile receptors located in the skin.Proprioceptive accuracy appears to be an important aspect in the evaluation of sensorimotor functioning;however,no widely accepted standard assessment exists.In this systematic ...  相似文献   

7.
Abstract

The consistency of separate components of a timing response were measured, and the relationship of these consistencies to the changes in distance, speed, and resistance of the movement were determined. The inconsistency of the total response was less than the sum of the inconsistencies of the response components. Factors which increase the movement time (e.g., greater distance or slower speed) tend to decrease the consistency of both movement time and time of initiation of the response, tending to make the total response more inconsistent. There was a tendency for load to have a stabilizing effect on slower movements and to decrease the consistency of faster movements.  相似文献   

8.
Abstract

It is well documented that simple reaction time (RT) varies inversely with stimulus intensity, but there is disagreement as to which stimulus modality produces the fastest simple RT. An investigation was conducted to equate two stimulus modalities, auditory (A) and electrocutaneous (EC), using varying stimulus intensities in a simple RT protocol. A second investigation was then conducted to examine neuromotor characteristics of stimulus-evoked responses using previously equated A and EC stimuli of varying intensity from the first investigation. Results showed that RT, premotor time (PMT), and motor time (MT) were all inversely related to stimulus intensity, while maximum displacement (MAXD) was directly related to stimulus intensity, and movement time was not affected by stimulus intensity. We conclude that: (a) both central and peripheral components of RT are altered by varying stimulus intensities, and (b) rapid movements are enhanced by increasing stimulus intensity.  相似文献   

9.
Purpose

The purposes of this study were to: (a) examine the effect of experience and goal constraints (speed, accuracy) on kicking patterns; (b) determine if effective striking mass was independent of ankle velocity at impact; and (c) determine the accuracy of kicks relative to independent factors.

Method

Twenty participants were recruited to kick at 3 different velocities with and without an accuracy requirement. Multivariate analysis of variance determined if relative timing of joint angular velocities changed during the kick. Chi-square analysis determined if calculated effective mass was independent of ankle velocity at impact. Analysis of variance (ANOVA) was used to examine differences in absolute constant error and variable error according to independent factors.

Results

Results indicated that experience and speed affect absolute timing of joint velocities with no changes in the relative timing of peak joint velocity across independent factors. Chi-square analysis indicated that calculated effective mass is not independent of ankle velocity. ANOVA indicated that experienced performers displayed less variability error than did inexperienced performers.

Conclusion

It was concluded that: (a) Experience, velocity, and accuracy do not affect the relative timing of kicks; (b) kickers trade ankle velocity at impact for greater effective striking mass and ball velocity; and (c) variability in ball placement is affected by experience.  相似文献   

10.
Abstract

Two alternative interpretations to the one proposed by Christina, Fischman, Vercruyssen, and Anson (1982) were investigated. They interpreted the simple reaction time (SRT) increase they found, which was thought to reflect an increase in programming time, to be due to the increase in number of movement parts from one response to another. Experiment 1(N = 15 males) tested the alternative interpretation that the SRT increase was caused by the difference in how the first movement part of the three responses was executed. However, no evidence was found to support this interpretation. Experiment 2 (N = 15 males) tested the alternative interpretation that the SRT increase was due to the increase in the demand for movement accuracy from one response to another. The results revealed that only a very small portion of the SRT increase could be attributed to the increased accuracy demand while the major portion of the increase was due to the increase in number of movement parts.  相似文献   

11.
Immersive environments induced by audiovisual stimuli are hypothesised to facilitate the control of movements and ameliorate fatigue-related symptoms during exercise. The objective of the present study was to investigate the effects of pleasant and unpleasant audiovisual stimuli on perceptual and psychophysiological responses during moderate-intensity exercises performed on an electromagnetically braked cycle ergometer. Twenty young adults were administered three experimental conditions in a randomised and counterbalanced order: unpleasant stimulus (US; e.g. images depicting laboured breathing); pleasant stimulus (PS; e.g. images depicting pleasant emotions); and neutral stimulus (NS; e.g. neutral facial expressions). The exercise had 10 min of duration (2 min of warm-up?+?6 min of exercise?+?2 min of warm-down). During all conditions, the rate of perceived exertion and heart rate variability were monitored to further understanding of the moderating influence of audiovisual stimuli on perceptual and psychophysiological responses, respectively. The results of the present study indicate that PS ameliorated fatigue-related symptoms and reduced the physiological stress imposed by the exercise bout. Conversely, US increased the global activity of the autonomic nervous system and increased exertional responses to a greater degree when compared to PS. Accordingly, audiovisual stimuli appear to induce a psychophysiological response in which individuals visualise themselves within the story presented in the video. In such instances, individuals appear to copy the behaviour observed in the videos as if the situation was real. This mirroring mechanism has the potential to up-/down-regulate the cardiac work as if in fact the exercise intensities were different in each condition.  相似文献   

12.
While motor dominance appears to drive limb selection for reaching movements at the midline and ipsilateral (dominant) side, this study examined the possible determinants associated with what drives the programming of movements in response to stimuli presented in contralateral space. Experiment 1 distinguished between object proximity and a hemispheric bias for using the hand on the same side as the stimulus by comparing imagined and actual reaching with arms uncrossed and crossed. Experiment 2 examined the role of comfort in limb selection via participants reaching for a cube under two conditions: 1- and multiple-df movements. The first experiment demonstrated a proximity effect; participants preferred to keep their arms crossed to reach with the hand closest to the stimulus rather than uncrossing their arms to support a bias. Comfort was eliminated when participants continued to prefer the nondominant hand, even though they were able to reach with the dominant hand at all positions using only a 1-df movement. In summary, we offer evidence suggesting that limb selection in response to stimuli presented in contralateral hemispace is determined primarily by information related to the proximity between the stimulus and the hand.  相似文献   

13.
Abstract

The physical stimulus-psychological response relationship has been described as being either a prothetic or a metathetic continuum. That is, as the stimulus intensity increases, the response magnitude increases (prothetic) or stays the same (metathetic). The first experiment of this study considered this relationship for a movement having the final limb position, or location, as its goal. The second experiment focused on an extent movement. Subjects were tested on a linear positioning apparatus in both experiments using the method of constant stimuli for determining thresholds. On the basis of the Weber ratios and the JND's for the three increasing movement locations and extents, a metathetic continuum was determined as best describing location movements, while a prothetic continuum was considered more appropriate for extent movements. JND's indicated sensitive discrimination for location movements (1.08 to 1.39 cm for 25 to 75 cm locations) and less precise discrimination capability for extent movements (2.49 to 5.76 cm for 25 to 75 cm extents). Results are discussed in terms of their possible implications for addressing issues related to mechanisms subserving active kinesthesis, and in terms of their implications for experimental procedures for learning and memory investigations using discrete positioning responses.  相似文献   

14.
Abstract

Researchers have suggested that skill performance deteriorates when people try to exert conscious control over automatic actions. Unfortunately, little is known about the effects of different types of conscious processing on skilled performance by expert athletes. We conducted two experiments to address this issue. Experiment 1 investigated the influence of a specific form of conscious control (making technical adjustments to a stroke) on the putting skills of expert golfers. The expert golfers maintained putting proficiency (i.e. number of putts holed) when making technical adjustments. However, this form of conscious processing altered the timing and consistency of golfers' putting strokes. Experiment 2 compared the influence of technical adjustments and conscious monitoring (paying attention to the execution of the stroke) on expert golfers' putting skills. Technical adjustments had no disruptive influence on expert golfers' putting proficiency but did reduce the consistency of their strokes. However, conscious monitoring was found to impair putting proficiency. The implications of the work for theory and future work are discussed.  相似文献   

15.
Abstract

The present study attempted to determine whether the nature of training experiences influences the development of coincident timing skill in young children. The task involved visual tracking of a moving light sequence and a 43 cm arm movement to a padded target. Subjects attempted to tap the target coincident with the completion of the light sequence. Sixty first grade children were randomly assigned to one of five groups, with an equal number of males and females in each group. Subjects assigned to the training groups received 48 trials on each of two days, with stimulus speeds that were either slow (179 cm/sec or 4 mph), fast (313 cm/sec or 7 mph), varied-random (179, 224, 268, 313 cm/sec or 4, 5, 6, 7 mph), or varied-blocked (i.e., 6 consecutive trials with one speed before changing to another). Control subjects performed a neutral coloring activity during the training phase of the experiment. All subjects were then given 10 trials on a third day with each of two stimulus speeds not experienced previously; one slow (134 cm/sec or 3 mph) and one fast (358 cm/sec or 8 mph). During transfer trials all groups were more accurate with the fast than with the slow speed stimulus. Training method mattered most during slow speed transfer trials, with the most accurate performance demonstrated by the group receiving varied-blocked speeds during training. The least effective methods were fast speed training, especially for males, and varied-random speed training. It was concluded that training sessions for the development of coincident timing skill in young children should emphasize slower speed stimuli and blocking of additional speeds which are more rapid.  相似文献   

16.
Abstract

The present study was designed to examine the influence of personal (i.e., social goal orientations or definitions of success that include interpersonal relationships) and situational (i.e., peer influence) factors on decisions surrounding unsportsmanlike play. Middle school students (ages 11–15 years) completed a measure to assess task, ego, and social goal orientations. Participants also read scenarios about unsportsmanlike actions and responded to questions tapping the intention to perform those actions. A series of hierarchical regression analyses revealed that in certain peer contexts, social goal orientations influenced unsportsmanlike play responses above and beyond the contribution of task and ego goal orientations. Results varied for boys and girls and provide support for including social goal orientations in achievement motivation research in the physical domain.  相似文献   

17.
The purpose of the present study was to determine whether playing a specific ball sport, such as tennis, could maintain the coincidence-timing (CT) performance of older adults at a similar level to that of younger ones. To address this question, tennis players and nonplayers of three different age ranges (ages 20-30, 60-70, and 70-80 years) performed a simple CT task consisting of timing their response (pressing a button) to coincide with the arrival of a stimulus at a target. The stimulus moved at either an accelerating, constant, or decelerating velocity. As expected, all participants were affected by the velocity manipulation, which led to late and early responses to accelerating and decelerating stimuli, respectively. Whereas this response bias was increasingly pronounced with advancing age in nonplayers, no difference was found among player groups of different ages. Finally, we showed that the length of the visuomotor delay could explain the effect of nonconstant velocities.  相似文献   

18.
Abstract

Release velocity and accuracy are vital components of throwing performance. However, there is no published research on these parameters for throwing in cricket. In this study, we investigated the throwing performance of 110 cricket players from six different populations: elite senior males, elite under-19 junior males, elite under-17 junior males, elite senior females, elite under-19 junior females, and sub-elite senior males. Based on a specifically designed cricket throwing test, participants were assessed for (1) maximal throwing velocity and (2) throwing accuracy at maximal velocity and at three sub-maximal velocities. Elite senior males exhibited the highest peak and mean maximal throwing velocities (P≤0.001). Furthermore, the groups of males had significantly higher peak and mean maximal throwing velocities than the groups of females (P≤0.01). A speed–accuracy trade-off existed such that all groups demonstrated improved accuracy scores at velocities between 75% and 85% maximal throwing velocity compared with 50% maximal throwing velocity and 100% perceived maximal exertion. The results indicate that sex, training experience (years training), and training volume (training time per week) may contribute to throwing performance in cricket players. Further research should focus on understanding the mechanisms behind the observed differences between these groups. This is the first study to describe the inherent throwing profiles of different cricket playing populations. Potentially, we have identified stimulus material for future training developments.  相似文献   

19.
Two experiments (n = 10) were conducted to determine the effects of roller massager (RM) on ankle plantar flexor muscle recovery after exercise-induced muscle damage (EIMD). Experiment 1 examined both functional [i.e., ankle plantar flexion maximal isometric contraction and submaximal (30%) sustained force; ankle dorsiflexion maximal range of motion and resistance to stretch; and medial gastrocnemius pain pressure threshold] and morphological [cross-sectional area, thickness, fascicle length, and fascicle angle] variables, before and immediately, 1, 24, 48, and 72 h after an EIMD stimulus. Experiment 2 examined medial gastrocnemius deoxyhaemoglobin concentration kinetics before and 48 h after EIMD. Participants performed both experiments twice: with (RM) and without (no-roller massager; NRM) the application of a RM (6 × 45 s; 20-s rest between sets). RM intervention did not alter the functional impairment after EIMD, as well as the medial gastrocnemius morphology and oxygenation kinetics (P > 0.05). Although, an acute increase of ipsilateral (RM = + 19%, NRM = ?5%, P = 0.032) and a strong tendency for contralateral (P = 0.095) medial gastrocnemius pain pressure threshold were observed. The present results suggest that a RM has no effect on plantar flexors performance, morphology, and oxygenation recovery after EIMD, except for muscle pain pressure threshold (i.e., a soreness).  相似文献   

20.
ABSTRACT

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s?1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L?1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8–11; B[La], 0.8–1.0; CMJ height, 1.6–2.0; CMJ PPO, 1.0–1.8; CMJ PCV, 0.04–0.06; CMJ 100ms-Impulse, 5.7–11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.  相似文献   

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