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Bruce Abernethy and David G. Russell

Two experiments are described comparing the temporal and spatial characteristics of the anticipatory cues used by expert (n=20) and novice (n=35) racquet sport players. In both experiments the perceptual display available in badminton was simulated using film, and display characteristics were selectively manipulated either by varying the duration of the stroke sequence that was visible (Experiment 1) or by selectively masking specific display features (Experiment 2). The subjects* task in all cases was to predict the landing position of the stroke they were viewing. It was found in Experiment 1 that experts were able to pick up more relevant information from earlier display cues than could novices, and this appeared in Experiment 2 to be due to their ability to extract advance information from the playing side arm, in addition to the racquet itself. These differences, it was concluded, were congruent with predictions that could be derived from traditional information-processing notions related to recognition of display redundancy. The roles of different anticipatory cue sources in the independent predictions of stroke speed and direction were also examined, and it was concluded that directional judgments were more dependent on cue specificity than were depth judgments.

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David Collins, Bruce Hale and Joe Loomis

Studies of sport participation that include emotional responses, particularly anger, are frequently flawed because measures consist of associative paper–pencil inventories and archival data. In the present study, startle response (an aversive reflex) was enhanced during an unpleasant emotional state and diminished in a pleasant emotional context. Nonsignificant differences on this dispositional measure between 36 athletes and nonathletes did not replicate findings differing normals and psychopaths (Patrick, Bradley, & Lang, 1993) on emotional responsivity. Similarity was also apparent in experiential aspects of anger responsivity as revealed by the check for differences in attributional style. No significant intergroup differences were found in participants’ responses to realistic situations (termed vignettes), in evaluation of the anger/provocation inherent in the situation, in the reasons attributed to the “frustrater,” or in self-reported intended response. Implications for future sport research on emotional responsivity, anger and aggressive behavior are discussed.

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Tim Blackmore, David Jessop, Stewart Bruce-Low and Joanna Scurr

Despite manufacturer claims that athletic socks attenuate force during exercise, no device exists to assess this. Therefore, this study outlines the development of a custom-built impact-testing device for assessing the cushioning properties of socks. The device used a gravity-driven impact striker (8.5 kg), released from 0.05 m, which impacted a no-sock, sock or a basic shoe/sock condition in the vertical axis. A load cell (10,000 Hz) assessed peak impact force, time to peak impact force and loading rate. Reliability was investigated between day, between trial and within trial. Excellent reliability (coefficient of variation < 5% adjusted for 95% confidence limits) was reported for peak impact force in all conditions, with no evidence of systematic bias. Good reliability (coefficient of variation < 10% adjusted for 68% confidence limits) was reported for time to peak impact force and loading rate with some evidence of systematic bias. It was concluded that the custom-built impact-testing device was reliable and sensitive for the measurement of peak impact force on socks.

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Aaron Chin, David Lloyd, Jacqueline Alderson, Bruce Elliott and Peter Mills

The predominance of upper-limb elbow models have been based on earlier lower-limb motion analysis models. We developed and validated a functionally based 2 degree-of-freedom upper-limb model to measure rotations of the forearm using a marker-based approach. Data were collected from humans and a mechanical arm with known axes and ranges of angular motion in 3 planes. This upper-limb model was compared with an anatomically based model following the proposed ISB standardization. Location of the axes of rotation relative to each other was determined in vivo. Data indicated that the functional model was not influenced by cross-talk from adduction-abduction, accurately measuring flexion-extension and pronation-supination. The functional flexion-extension axis in vivo is angled at 6.6° to the anatomical line defined from the humeral medial to lateral epicondyles. The pronation-supination axis intersected the anatomically defined flexion-extension axis at 88.1°. Influence of cross-talk on flexion-extension kinematics in the anatomical model was indicated by strong correlation between flexion-extension and adduction-abduction angles for tasks performed by the subjects. The proposed functional model eliminated cross-talk by sharing a common flexion axis between the humerus and forearm. In doing so, errors due to misalignment of axes are minimized providing greater accuracy in kinematic data.

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Trish Gorely, Anne Jobling, Kellie Lewis and David Bruce

The purpose was to develop an evaluative case study of six 3-hr sessions, spaced over 3 months, of psychological skills training (PST) provided to athletes with an intellectual disability who were training for the Basketball Australia State Championships. Participants were 7 males and 7 females, aged 15.8 to 27.1 years, with a receptive language level of 7 to 13.7 years, 2 female coaches, 2 psychologists, and 1 registered psychologist supervisor. Sessions focused specifically on stress management, with primary attention given to cue words, breathing techniques, and positive thinking. Findings, based on interviews and participant observations, revealed that all participants believed that the PST was appropriate and worthwhile.

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David Whiteside, Bruce Elliott, Brendan Lay and Machar Reid

The importance of the flat serve in tennis is well documented, with an abundance of research evaluating the service technique of adult male players. Comparatively, the female and junior serves have received far less attention. Therefore, the aims of this study were to quantify the flat serve kinematics in elite prepubescent, pubescent, and postpubescent female tennis players. Full body, racket, and ball kinematics were derived using a 22-camera Vicon motion capture system. Racket velocity was significantly lower in the prepubescent group than in the two older groups. In generating racket velocity, the role of the serving arm appears to become more pronounced after the onset of puberty, whereas leg drive and “shoulder-over-shoulder” rotation mature even later in development. These factors are proposed to relate to strength deficits and junior players’ intentions to reduce the complexity of the skill. Temporally, coupling perception (cues from the ball) and action (body movements) are less refined in the prepubescent serve, presumably reducing the “rhythm” (and dynamism) of the service action. Practically, there appears scope for equipment scaling to preserve kinematic relevance between the junior and senior serve and promote skill acquisition.

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Timothy A. Hanke, Bruce Kay, Michael Turvey and David Tiberio

Lateral stability and weight transfer are important for successful stepping and are associated with falls in older adults (OAs). This study assessed the influence of step pacing frequency during medial–lateral stepping in place on body center of mass and lower limb movement in young adults, middle-aged adults, and OAs. Medial–lateral center of mass and stepping limb motion and lower limb loading data were collected. Center of mass motion decreased with increasing pacing frequency and increased to a lesser extent with decreasing pacing frequency. Step length was relatively resistant to changes in pacing frequency. OAs exhibited reductions in whole body and stepping motion compared with younger adults. OAs exhibited greater support limb loading. OAs adapt both postural and stepping strategies to successfully step under time-critical conditions.

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Warren Young, Peter Clothier, Leonie Otago, Lyndell Bruce and David Liddell

Context:

Flexibility tests are sometimes thought to be related to range of motion in dynamic activities, but such a relationship remains to be determined.

Objective:

To determine the correlation between flexibility and hip and knee angles in Australian football kicking.

Design:

Correlation.

Setting:

Biomechanics laboratory.

Participants:

16 Australian Rules football players.

Main Outcome Measures:

Hip and knee angles of the preferred kicking leg in a relaxed position were determined with a modified Thomas test. Maximum hip extension, the knee-flexion angle in this position, the maximum knee-flexion angle, and the hip angle at this position during the swing phase of maximum-effort drop-punt kicks were determined.

Results:

Significant correlations were found between hip flexibility and maximum hip extension (r = .65, P < .01) and hip angle at the maximum knee-flexion angle (r = .70, P < .01).

Conclusions:

The data indicate a moderate association between hip flexibility and hip angles during kicking.

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Robert J. Rotella, Bruce Gansneder, David Ojala and John Billing