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The Past and Future of Clock-Like Timing in Motor Performance

Howard N. Zelaznik

Much motor performance occurs with a background of timing constraints. The baseball batter must place his or her bat in the right place at the right time. We can consider this a task of anticipation timing. On the other hand, many tasks have the timing of a serial task as a goal. The classic

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Comparison of the Relation between Timing and Force Control during Finger-Tapping Sequences by Pianists and Nonpianists

Nobuyuki Inui and Takuya Ichihara

To examine the relation between timing and force control during finger tapping sequences by both pianists and nonpianists, participants lapped a force plate connected to strain gauges. A series of finger tapping tasks consisted of 16 combinations of pace (intertap interval: 180. 200, 400. or 800 ms) and peak force (50, 100. 200. or 400 g). Analysis showed that, although movement timing was independent of force control under low or medium pace conditions, there were strong interactions between the 2 parameters under high pace conditions. The results indicate that participants adapted the movement by switching from separately controlling these parameters in the slow and moderate movement to coupling them in the fast movement. While variations in intertap interval affected force production by nonpianists. they had little effect for pianists. The ratios of time-to-peak force to press duration increased linearly in pianists but varied irregularly in nonpianists, as the required force decreased. Thus, pianists regulate peak force by timing control of peak force to press duration, suggesting that training affects the relationship between the 2 parameters.

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Development of Force Control and Timing in a Finger-Tapping Sequence with an Attenuated-Force Tap

Nobuyuki Inui and Yumi Katsura

We conducted an experiment to examine age-related differences in the control of force and timing in a finger-tapping sequence with an attenuated-force tap. Participants between 7 and 20 years old tapped on a load cell with feedback on practice trials. They were required to recall the force pattern (300 g, 300 g, 300 g, 100 g) and the intertap interval (400 ms) without feedback on test trials. Analysis indicated that the last attenuated tap affected the first three taps of the tapping sequence in adults and adolescents but not in children. Adults and adolescents appeared to respond with four taps as a chunk, resulting in a contextual effect on the timing of force control, but younger children had difficulty with such chunking. Further, adults and adolescents were able to more accurately produce individual force magnitudes to match target magnitudes than younger children. For the ratio of force in serial positions 1:4, 2:4, and 3:4, consequently, 7- to 8-year-old children had lower ratios than the other age groups. Although there was no difference among age groups for timing control of peak force to press duration as a control strategy of force, 7- to 8-year-old children spent more time to produce force than the other age groups. Peak force with a decreased force was more variable in the attenuated force serial position (4) than in the other serial positions in all five age groups. Peak force variability was particularly robust in younger children. These findings suggest that younger children have difficulty with both temporal and spatial (i.e., magnitude) components of force control.

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Frequent Carbohydrate Ingestion Reduces Muscle Glycogen Depletion and Postpones Fatigue Relative to a Single Bolus

Campbell Menzies, Michael Wood, Joel Thomas, Aaron Hengist, Jean-Philippe Walhin, Robbie Jones, Kostas Tsintzas, Javier T. Gonzalez, and James A. Betts

carbohydrate to ingest during exercise ( Jeukendrup, 2014 ), there is a limited evidence base regarding when carbohydrate should be ingested (i.e., the timing/pattern of nutrient delivery). The timing of carbohydrate ingestion during exercise can mediate various physiological responses that impact

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Error-Correction Processing in Timing Lights for Measuring Sprint Performance: Does It Work?

Stefan Altmann, Steffen Ringhof, Benedikt Becker, Alexander Woll, and Rainer Neumann

Sprint testing plays a key role in the physical assessment of team sport athletes. Most commonly, timing lights are the method of choice for measuring sprint capacities. 1 However, in terms of single-beam timing lights, the system can be triggered prematurely by an athlete’s upper or lower limbs

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Coincidence-Anticipation Timing

Harry J. Meeuwsen, Sinah L. Goode, and Noreen L. Goggin

The purpose of this experiment was to replicate and extend earlier experiments used to investigate the effect of the motor response, experience with open skills, and gender on coincidence-anticipation timing accuracy. Fifteen males and fifteen females, who were all right-eye and right-hand dominant, performed a switch-press and a hitting coincident-anticipation timing task on a Bassin Anticipation Timing apparatus with stimulus speeds of 4 mph, 8 mph, and 12 mph. Level of experience with open skills was determined by a self-report questionnaire and vision was screened using the Biopter Vision Test. Experience with open skills explained some of the variable error data, possibly supporting a socio-cultural explanation of gender differences. Males performed with less variable and absolute error than females, while performance bias was different for the genders on the two tasks. All participants performed with less absolute error on the 8 mph stimulus speed. The type of task and stimulus speed affected performance variability differently. Based on the task characteristics and these data, it was concluded that optimal effector anticipation is more strongly linked to stimulus speed than receptor anticipation. Future studies will have to confirm this conclusion.

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Are the Elderly Able to Appropriately Reprogram Their Actions?

Luis Augusto Teixeira, Mariana Marília Franzoni, and Juliana Bayeux da Silva

Movement reprogramming in a task requiring timing accuracy was investigated in young and elderly individuals. The task consisted of manually hitting a hemiball in synchrony with the arrival of a moving light stimulus running through an electronic trackway. Movement reprogramming was required by unexpectedly changing the regular stimulus velocity at different moments before the due time of arrival at the interception position. Such changes produced times after velocity decrease (TAVD) between 150 ms and 750 ms, representing the periods of time available for generation of new movement timing specifications. Effect of probability of stimulus velocity change was investigated by comparing the conditions of 25% and 50% of chance of velocity decrease. Analysis of performance in conditions of velocity decrease showed an enlargement of temporal error as a function of longer TAVDs up to 300-375 ms. In conditions in which TAVDs were longer than 375 ms young participants showed a progressive improvement of accuracy over time, while the elderly were unable to improve their performance even for a TAVD of 750 ms. A trend toward a more efficient reprogramming with reduced uncertainty was observed only in the young. These results indicate that movement reprogramming is a continuous process in young individuals, but it is impaired in the elderly, preventing an appropriate reorganization of the action.

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Optimized Simulation of Upper Body Timing on the Production of Bat-Head Speed in Baseball Batting

Kazumichi Ae, Dave Burke, Takashi Kawamura, and Sekiya Koike

baseball movements such as throwing and hitting are complex skills, differences in the coordination of the multijoint movement would affect the generation of the distal point velocity. Herring and Chapman 9 described changes in timing of the onset of joint torques in a simulated throwing motion maximized

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An Evaluation of the Minimum-Jerk and Minimum Torque-Change Principles at the Path, Trajectory, and Movement-Cost Levels

Mary D. Klein Breteler, Ruud G.J. Meulenbroek, and Stan C.A.M. Gielen

In the present study we evaluated the minimum-jerk and the minimum torque-change model at the path, trajectory, and movement-cost levels. To date, most evaluations of these models have mainly been restricted to path comparisons. Assessments of the time courses of realized jerk and torque changes are surprisingly lacking. Moreover, the extent to which the presumed optimized parameters change as a function of the duration and other temporal features of aiming movements has never been investigated, most probably because the models presuppose movement time. In order to till mis gap, we analyzed a subset of the data of an earlier experiment in which 12 participants performed leftward and rightward planar pointing movements. Hand displacements and joint excursions were recorded with a 3D motion-tracking system and subsequently evaluated by means of model-based analyses. The results show that despite a good agreement between observed paths and predicted paths, especially by the minimum torque-change model, the time courses of jerk and torque changes of observed and modeled movements differed considerably. These differences could mainly be attributed to asymmetrical properties of the time functions of slow movements. Variations of movement costs as a function of movement lime and skewness of tangential velocity profiles show that, especially at high movement speed, costs increase exponentially with departures of symmetry. It is concluded that trajectory-formation models have limited explanatory power in situations that require demanding information processing during the homing-in phase of goal-directed movements. However. for slow movements, deviations from the optimal timing profiles require little extra costs in terms of jerk or torque change.

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Timing of Caffeine Ingestion Does Not Improve Three-Point Shooting Accuracy in College Basketball Players

Zhi Sen Tan, Rachelle Yahn Yee Sim, Masato Kawabata, Dorrain Yanwen Low, Yulan Wang, and Stephen F. Burns

ecological validity, some game-like demand should be introduced beforehand as accuracy is negatively affected by fatigue ( Mulazimoglu et al., 2017 ). This study examined the effects of caffeine (3 mg/kg of body mass) ingestion timing on three-point shooting accuracy in college basketball players during