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Tracy L. Pellett and Joyce M. Harrison

This study examined low- and high-skilled students’ (N = 68) immediate practice success in response to a teacher’s specific, congruent, and corrective feedback for different tasks (extension, refinement, and application). Data were gathered from an introductory 11-day volleyball unit taught to female seventh and eighth graders (two intact classes) by a physical education specialist. Practice success immediately after teacher feedback was characterized by significant improvement in performance by both ability groups for extension, refinement, and application tasks for the pass and refinement and application tasks for the set.

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David W. Franklin

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Paul Ford, Nicola J. Hodges, Raoul Huys and A. Mark Williams

The importance of action-effects for the performance of a soccer kick was examined. Novice, intermediate, and skilled players performed a soccer chip task with the intention of getting the ball over a height barrier to a near or far ground-level target under three conditions: full vision, no vision following ball contact with and without knowledge of results (KR). The removal of vision of the ball trajectory resulted in increased radial error, irrespective of the presence or absence of KR but in a skill-level and target dependent manner. At the near target, novice participants relied on ball trajectory information. Intermediate performers were affected by its removal across both target conditions, whereas skilled participants were not affected by the removal of ball vision. Variability in knee-ankle coordination significantly decreased when vision of the ball trajectory was removed, irrespective of KR and skill level. Although across skill level there was evidence that action-effects information is used to execute the action when it is available, only at the lower levels of skill did this information aid outcome attainment. There was no evidence to suggest that with increasing skill the dependence on this information increases.

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Lawrence E. M. Grierson, Claudia Gonzalez and Digby Elliott

This study was designed to examine the importance of vision to corrective processes associated with a mechanical perturbation to the limb during goal-directed aiming. With a hand held stylus, under vision and no vision conditions, performers reached to a target represented by the intersection of perpendicular lines. The stylus was connected to an air compressor and engineered such that 80 ms following movement initiation reaches were perturbed by a short air burst either in the direction of, or opposite to, the movement. Spatial position analysis of the limb at early kinematic landmarks revealed that the single direction bursts were successful in advancing and hindering the movement progress. Furthermore, within subject trial-to-trial variability analysis indicated that performers adopted different control strategies for dealing with the perturbations depending on the availability of vision. The present findings suggest that a continuous form of online control is exercised during the early portions of the aiming trajectories. This form of control may be mediated by visual or proprioceptive information.

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Elizabeth Swann

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David Kahan

This case study of a student teacher (ST) and her cooperating teacher (CT) employed an AB1B2A reversal design over an entire high-school-level student teaching practicum to determine the effect of a two-way, bug-in-the-ear radio device on dyadic intralesson communication characteristics, participant role satisfaction with the device, and attitude toward using the device and additional equipment. Likert-scale, postlesson questionnaires measured participant satisfaction with their roles, the communication, and equipment. An exit interview was conducted to obtain explanations for data trends. Intralesson communication was characterized by its short duration (M = 15.8 s) and low rate (M = 0.25 communications/min). It was predominantly CT-initiated, management oriented, neutral, and specific. And it was balanced between descriptive, prescriptive, and interrogative comments. Analysis of exit interviews revealed three themes to explain characteristics of and responses to communication, and the devices used to elicit it: CT/ST interpersonal and professional compatibility, role clarity, and commitment to perceived role function. The radio device/intervention did not differentiate communication characteristics from baseline or reversal phases; however, participants identified it as a discrete and immediate communication tool that promoted ST “with-it-ness” and autonomy.

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Courtney Sullivan, Johann C. Bilsborough, Michael Cianciosi, Joel Hocking, Justin T. Cordy and Aaron J. Coutts

Objectives:

To determine the physical activity measures and skill-performance characteristics that contribute to coaches’ perception of performance and player performance rank in professional Australian Football (AF).

Design:

Prospective, longitudinal.

Methods:

Physical activity profiles were assessed via microtechnology (GPS and accelerometer) from 40 professional AF players from the same team during 15 Australian Football League games. Skill-performance measure and player-rank scores (Champion Data Rank) were provided by a commercial statistical provider. The physical-performance variables, skill involvements, and individual player performance scores were expressed relative to playing time for each quarter. A stepwise multiple regression was used to examine the contribution of physical activity and skill involvements to coaches’ perception of performance and player rank in AF.

Results:

Stepwise multiple-regression analysis revealed that 42.2% of the variance in coaches’ perception of a player’s performance could be explained by the skill-performance characteristics (player rank/min, effective kicks/min, pressure points/min, handballs/min, and running bounces/min), with a small contribution from physical activity measures (accelerations/min) (adjusted R 2 = .422, F 6,282 = 36.054, P < .001). Multiple regression also revealed that 66.4% of the adjusted variance in player rank could be explained by total disposals/min, effective kicks/min, pressure points/min, kick clangers/min, marks/min, speed (m/min), and peak speed (adjusted R 2 = .664, F 7,281 = 82.289, P < .001). Increased physical activity throughout a match (speed [m/min] β – 0.097 and peak speed β – 0.116) negatively affects player rank in AF.

Conclusions:

Skill performance rather than increased physical activity is more important to coaches’ perception of performance and player rank in professional AF.

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Chris R. Abbiss, Kevin G. Thompson, Marcin Lipski, Tim Meyer and Sabrina Skorski

The purpose of this study was to compare the pacing profiles between distance- and duration-based trials of short and long duration. Thirteen trained cyclists completed 2 time-based (6 and 30 min) and 2 distance-based (4 and 20 km) self-paced cycling time trials. Participants were instructed to complete each trial with the highest average power output. Ratings of perceived exertion (RPEs) were measured throughout the trials. Average power output was not different between the 4-km and 6-min trials (324 ± 46 vs 325 ± 45 W; P = .96) or between the 20-km and 30-min trials (271 ± 44 vs 267 ± 38 W; P = .24). Power output was greater on commencement of the distance-based trials when short and long trials were analyzed together. Furthermore, the rate of decline in power output over the 1st 40% of the trial was greater in the 20-km trial than in the 30-min trial (P = .01) but not different between the 4-km and the 6-min trials (P = .13). RPE was greater in the 4-km trial than in the 6-min trial but not different between the 20-km and 30-min trials. These findings indicate that athletes commenced distance-based time trials at relatively higher power outputs than a similar time-based trial. Such findings may result from discrete differences in our ability to judge or predict an exercise endpoint when performing time- and distance-based trials.

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Michael B. Martin and Mark H. Anshel

Two experiments were conducted to examine the effect of self-monitoring (SM) strategies on motor performance of varied difficulty. In a pilot test, participants’ perceptions of task difficulty agreed with performance on the easy task. Participants perceived the hard task to be significantly more difficult than indicated by the performance scores and perceived the easy task to be significantly less difficult than their performance on the complex task (p < .05). In the subsequent experiment, subjects performed 90 trials on either the difficult or easy motor task using either positive self-monitoring (PSM), negative self-monitoring (NSM), or no self-monitoring. MANOVAs indicated that PSM resulted in superior performance in comparison to NSM across trials while performing the difficult task (p < .05). In the easy task, PSM was inferior to NSM on motor performance across trials (p < .01). Further results also indicated that negative affect significantly decreased for PSM performing the difficult task, and for NSM performing the easy task.

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Patrice R. Rougier and Samir Boudrahem

Past studies have emphasized the beneficial effect of additional visual feedback (VFB) on the capacity of healthy adults to decrease the amplitudes of the center-of-pressure minus center-of-gravity (CP-CGv) movements. To better assess these capacities, 56 subjects were asked to stand still on a force platform and to use the visual information provided. Dependency coefficients, based on their capacity to lower their CP-CGv movements and therefore relax their lower limb muscles, as well as parameters aimed at characterizing their postural strategies were measured across VFB conditions including (1) CP displacements in real time (VFBCP0), (2) CP displacements with a 600-ms delay (VFBCP600), and (3) CP-CGv displacements with a 600-ms delay (VFBCP-CG600). A non-VFB condition (eyes open) was also included. Several linear correlations were used to specify the relation between subjects’ capacity to relax, compared with the VFBCP0 condition, across the three remaining conditions. The data highlight the complementary nature of the VFB conditions and establish the postural control behaviors necessary to use these VFB protocols efficiently.