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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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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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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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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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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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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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Arturo Forner-Cordero, Virgínia H. Quadrado, Sitsofe A. Tsagbey and Bouwien C.M. Smits-Engelsman

perturbations lead to adaptations, which are stronger ( Krakauer & Shadmehr, 2006 ) and more general ( Malfait & Ostry, 2004 ) than those adaptations caused by sudden and obvious perturbations. The coincident timing task consists of reaching a fixed target with the hand at the same instant as a moving cue

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Catherine R. Marinac, Mirja Quante, Sara Mariani, Jia Weng, Susan Redline, Elizabeth M. Cespedes Feliciano, J. Aaron Hipp, Daniel Wang, Emily R. Kaplan, Peter James and Jonathan A. Mitchell

is a considerable public health priority. Much of scientific research on the topic has focused on identifying what to eat or how much to exercise to control body weight. However, a small but growing body of evidence suggests the timing of behaviors is also important. 5 – 10 The most robust

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Kapria-Jad Josaphat, Vicky Drapeau, David Thivel and Marie-Eve Mathieu

-suppressing factors and decreases in appetite-inducing hormones following a single bout of medium- to high-intensity exercise ( Gomez-Merino et al., 2004 ; Schubert et al., 2014 ; Ueda et al., 2009 ). The timing of energy intake has been shown to be of importance regarding the control of body weight ( Arble et

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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.