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Senne Braem, Stephanie Supply, Sanne P. Roels and Wim Notebaert

Most cognitive control effects, although numerously reported in computer task studies, have rarely been tested outside the laboratory. The purpose of this study was twofold. First, we aimed to improve the ecological validity of a well-studied congruency effect. The Simon effect (Simon, 1969) is the observation that an irrelevant stimulus location can facilitate or impede task performance when it is congruent or incongruent with the response location. Secondly, we wanted to investigate the role of action experience on the Simon effect. In this study, experienced bowlers were asked to hit either the left- or rightmost pin, depending on the pitch of a tone. Irrelevant to the task, this tone could be presented in the congruent or incongruent ear. Our results demonstrate that the Simon effect can be observed outside the laboratory and that weekly training at bowling may help in shielding against irrelevant location stimuli.

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André Roca, Paul R. Ford, Allistair P. McRobert and A. Mark Williams

The ability to anticipate and to make decisions is crucial to skilled performance in many sports. We examined the role of and interaction between the different perceptual-cognitive skills underlying anticipation and decision making. Skilled and less skilled players interacted as defenders with life-size film sequences of 11 versus 11 soccer situations. Participants were presented with task conditions in which the ball was located in the offensive or defensive half of the pitch (far vs. near conditions). Participants’ eye movements and verbal reports of thinking were recorded across two experiments. Skilled players reported more accurate anticipation and decision making than less skilled players, with their superior performance being underpinned by differences in task-specific search behaviors and thought processes. The perceptual-cognitive skills underpinning superior anticipation and decision making were shown to differ in importance across the two task constraints. Findings have significant implications for those interested in capturing and enhancing perceptual-cognitive skill in sport and other domains.

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Eric L. Sauers, Danelle L. Dykstra, R. Curtis Bay, Kellie Huxel Bliven and Alison R. Snyder

Context:

Throwing-related arm injuries are common in softball pitchers and may lead to diminished health-related quality of life (HRQOL). Arm symptoms such as pain have been reported to be more common in healthy overhead athletes than nonoverhead athletes. Furthermore, more frequent shoulder symptoms and lower shoulder function have been demonstrated in athletes with self-reported history of shoulder injury.

Objective:

To evaluate the relationship between arm injury history, current pain rating, and HRQOL assessed via 2 region-specific patient self-report scales in high school and college softball pitchers.

Design:

Cross-sectional.

Setting:

High school and college athletic training facilities.

Participants:

25 female softball pitchers (10 high school, 15 college; 18 ± 2 y, 169 ± 7.6 cm, 67.5 ± 10.3 kg).

Intervention:

Self-reported arm injury history and rating of current pain and HRQOL were collected during the late season.

Main Outcome Measures:

A self-report questionnaire of arm injury history and current pain rating was used, and HRQOL was assessed via 2 region-specific scales: the Disabilities of the Arm, Shoulder, and Hand (DASH) and the Functional Arm Scale for Throwers© (FAST©). Correlational analysis was used to evaluate the relationships between arm injury history, current pain rating, and the DASH total score and sport module and the FAST total score, pitching module, and subscales.

Results:

A history of arm injury from throwing was reported by 64% of participants, 31% of whom had to cease activity for more than 10 d. The most common site of arm time-loss injury was the shoulder (81%). Mild to severe shoulder pain during the competitive season was reported by 60% of respondents. The DASH and the FAST total scores were significantly correlated (r = .79, P < .001). Respondent rating of shoulder pain correlated significantly with the DASH total (r = .69) and sports module (r = .69) and the FAST total (r = .71), pitching module (r = .65), and pain (r = .73), impairment (r = .76), functional-limitation (r = .79), disability (r = .52), and societal-limitations (r = .46) subscales.

Conclusion:

History of arm injury is common in female high school and college softball pitchers. Severe injury and elevated pain are associated with lower HRQOL that extends beyond the playing field.

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Kevin Currell, Steve Conway and Asker E. Jeukendrup

The aim of the study was to investigate the reliability of a new test of soccer performance and evaluate the effect of carbohydrate (CHO) on soccer performance. Eleven university footballers were recruited and underwent 3 trials in a randomized order. Two of the trials involved ingesting a placebo beverage, and the other, a 7.5% maltodextrin solution. The protocol comprised a series of ten 6-min exercise blocks on an outdoor Astroturf pitch, separated by the performance of 2 of the 4 soccer-specific tests, making the protocol 90 min in duration. The intensity of the exercise was designed to be similar to the typical activity pattern during soccer match play. Participants performed skill tests of dribbling, agility, heading, and shooting throughout the protocol. The coefficients of variation for dribbling, agility, heading, and shooting were 2.2%, 1.2%, 7.0%, and 2.8%, respectively. The mean combined placebo scores were 42.4 ± 2.7 s, 43.1 ± 3.7 s, 210 ± 34 cm, and 212 ± 17 points for agility, dribbling, heading, and kicking, respectively. CHO ingestion led to a combined agility time of 41.5 ± 0.8 s, for dribbling 41.7 ± 3.5 s, 213 ± 11 cm for heading, and 220 ± 5 points for kicking accuracy. There was a significant improvement in performance for dribbling, agility, and shooting (p < .05) when CHO was ingested compared with placebo. In conclusion, the protocol is a reliable test of soccer performance, and ingesting CHO leads to an improvement in soccer performance.

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Simon Roberts, Grant Trewartha and Keith Stokes

Purpose:

To assess the validity of a digitizing time–motion-analysis method for field-based sports and compare this with a notational-analysis method using rugby-union match play.

Method:

Five calibrated video cameras were located around a rugby pitch, and 1 subject completed prescribed movements within each camera’s view. Running speeds were measured using photocell timing gates. Two experienced operators digitized video data (operator 1 on 2 occasions) to allow 2-dimensional reconstruction of the prescribed movements.

Results:

Accuracy for total distance calculated was within 2.1% of the measured distance. For intraoperator and interoperator reliability, calculated distances were within 0.5% and 0.9%, respectively. Calculated speed was within 8.0% of measured photocell speed with intraoperator and interoperator reliability of 3.4% and 6.0%, respectively. For the method comparison, two 20-minute periods of rugby match play were analyzed for 5 players using the digitizing method and a notational time–motion method. For the 20-minute periods, overall mean absolute differences between methods for percentage time spent and distances covered performing different activities were 3.5% and 198.1 ± 138.1 m, respectively. Total number of changes in activity per 20 minutes were 184 ± 24 versus 458 ± 48, and work-to-rest ratios, 10.0%:90.0% and 7.3%:92.7% for notational and digitizing methods, respectively.

Conclusion:

The digitizing method is accurate and reliable for gaining detailed information on work profiles of field-sport participants and provides applied researchers richer data output than the conventional notational method.

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Mont Hubbard, Robin L. Hibbard, Maurice R. Yeadon and Andrzej Komor

This paper presents a planar, four-segment, dynamic model for the flight mechanics of a ski jumper. The model consists of skis, legs, torso and head, and arms. Inputs include net joint torques that are used to vary the relative body configurations of the jumper during flight. The model also relies on aerodynamic data from previous wind tunnel tests that incorporate the effects of varying body configuration and orientation on lift, drag, and pitching moment. A symbolic manipulation program, “Macsyma,” is used to derive the equations of motion automatically. Experimental body segment orientation data during the flight phase are presented for three ski jumpers which show how jumpers of varying ability differ in flight and demonstrate the need for a more complex analytical model than that previously presented in the literature. Simulations are presented that qualitatively match the measured trajectory for a good jumper. The model can be used as a basis for the study of optimal jumper behavior in flight which maximizes jump distance.

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John H. Lawrence III and T. Richard Nichols

Muscle actions are often defined within a single anatomical reference plane. Yet animals must control posture and movement within a three-dimensional (3-D) environment, responding to a 3-D array of perturbing forces. Based on information gained regarding the 3-D muscle mechanics at the cat ankle joint complex (companion paper), we decided to study how alterations in the 3-D AJC orientation might affect ankle joint postural control. We used a 6 degree-of-freedom force-moment sensor to assess the affect of ankle joint orientation on the 3-D isometric joint torques evoked by electrical stimulation of muscles crossing the ankle joint complex (AJC) in the deeply anesthetized cat. An orthogonal axis system was established at the designated ankle rotation center, such that pitch (flexion-extension), yaw (abduction-adduction), and roll (inversion-eversion) axis torques were calculated. Experimental results suggest that both the magnitude and sign of extra-sagittal torques from the gastrocnemius muscles are joint angle dependent. Also, the hind limb levering system stabilizes the AJC against large yaw and roll rotations away from the control position.

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John H. Lawrence III and T. Richard Nichols

Muscle actions are often defined with respect to a single anatomical reference plane based on a “predominant” functional activity. Yet animals must control posture and movement within a three-dimensional (3-D) environment, exerting control over more than one reference plane when responding to a 3-D array of perturbing forces. Consequently, enhanced knowledge concerning the 3-D torque capabilities of certain appendicular muscles might provide for greater understanding of the biomechanical basis for motor control. We propose that the cat postural control mechanism utilizes the inherent 3-D mechanical actions of ankle flexors and extensors to maintain extra-saggital joint stiffness. We used a 6 degree-of-freedom force-moment sensor to assess the effect of ankle joint orientation on the 3-D nature of isometric joint torques evoked by electrical stimulation of muscles crossing the AJC in the deeply anesthetized cat. An orthogonal axis system was established at the designated ankle rotation center, such that pitch (defining flexion-extension), yaw (abduction-adduction), and roll (inversion-eversion) axis torques were calculated. Experimental results show that the classical cat ankle flexor and extensors evoke large extra-sagittal torques as well. Also, the hind limb levering system stabilizes the AJC against large yaw and roll rotations away from the control position.

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Suzie Godfrey and Stacy Winter

This paper presents a reflective account of the sport psychology support work delivered across one season at a professional football academy by a neophyte practitioner. The development of the sport psychology program, referred to as Winning Mentality, was guided by Harwood and Anderson's (2015) 5C guidelines to psychological skills training.The Winning Mentality program outlined within this paper was delivered to the U9-U12 age groups and focused on the three key topics: (1) growth mind-set; (2) emotional control; and (3) confidence.The intervention comprised predominantly of classroom-based workshops delivered at the team level that focused on one topic per training cycle. Working with these young age groups uncovered a number of challenges that form the basis of this reflective account.Drawing upon child developmental literature was a necessity to ensure the effective matching of session content to the relevant age group. In addition, the heavily classroom-based nature of the program limited the youth footballers application of sport psychology techniques on the football pitch.Finally, opportunities to empower coaches with the knowledge and skills to apply psychological concepts within their training sessions should be welcomed.

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David W. Keeley, Gretchen D. Oliver, Christopher P. Dougherty and Michael R. Torry

The purpose of this study was to better understand how lower body kinematics relate to peak glenohumeral compressive force and develop a regression model accounting for variability in peak glenohumeral compressive force. Data were collected for 34 pitchers. Average peak glenohumeral compressive force was 1.72% ± 33% body weight (1334.9 N ± 257.5). Correlation coefficients revealed 5 kinematic variables correlated to peak glenohumeral compressive force (P < .01, α = .025). Regression models indicated 78.5% of the variance in peak glenohumeral compressive force (R2 = .785, P < .01) was explained by stride length, lateral pelvis flexion at maximum external rotation, and axial pelvis rotation velocity at release. These results indicate peak glenohumeral compressive force increases with a combination of decreased stride length, increased pelvic tilt at maximum external rotation toward the throwing arm side, and increased pelvis axial rotation velocity at release. Thus, it may be possible to decrease peak glenohumeral compressive force by optimizing the movements of the lower body while pitching. Focus should be on both training and conditioning the lower extremity in an effort to increase stride length, increase pelvis tilt toward the glove hand side at maximum external rotation, and decrease pelvis axial rotation at release.