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Jessyca N. Arthur-Cameselle and Molly Curcio

to begin recovery. This initial period in the recovery process is referred to in the literature as a turning point or tipping point , described as the “point at which the illness trajectory is interrupted” ( Fogarty & Ramjan, 2017 , p. 2) so that “the balance finally tipped in favor of pursuing

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Carl G. Mattacola

participate. This is especially true of the University of Kentucky and AT Still University. The wheel is turning and you can’t slow down, You can’t let go and you can’t hold on, You can’t go back and you can’t stand still — Robert Hunter The wheels certainly keep turning, and it is no time to slow down. The

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Mont Hubbard, Michael Kallay and Payam Rowhani

We have developed a mathematical model and computer simulation of three-dimensional bobsled turning. It is based on accurate descriptions of existing or hypothetical tracks and on dynamic equations of motion including gravitational, normal, lift, drag, ice friction, and steering forces. The three-dimensional track surface model uses cubic spline geometric modeling and approximation techniques. The position of the sled on the track is specified by the two variables α and β in the along-track and cross-track directions, differential equations for which govern the possible motions of the sled. The model can be used for studies involving (a) track design, (b) calculation of optimal driver control strategies, and (c) as the basis for a real-time bobsled simulator. It can provide detailed quantitative information (e.g., splits for individual turns) that is not available in runs at actual tracks. The model also allows for comparison of driver performance with the numerically computed optimum performance, and for safe experimentation with risky driving strategies.

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Rebecca Fernandes, Chris Bishop, Anthony N. Turner, Shyam Chavda and Sean J. Maloney

right, with 3 min between attempts. If the participants did not meet the turning line, their attempt was discarded and repeated after a recovery period. The times were recorded to the nearest 0.001 s, and the fastest time for each leg was used for to determine CODS performance. To determine the COD

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Haidzir Manaf, Maria Justine and Hui-Ting Goh

Attentional loadings deteriorate straight walking performance for individuals poststroke, but its effects on turning while walking remain to be determined. Here we compared turning kinematics under three attentional loading conditions (single, dual-motor, and dual-cognitive task) between stroke survivors and healthy controls. Nine chronic stroke survivors and 10 healthy controls performed the Timed Upand- Go test while their full-body kinematics were recorded. Onset times of yaw rotation of the head, thorax and pelvis segments and head anticipation distance were used to quantify turning coordination. Results showed that stroke survivors reoriented their body segments much earlier than the controls, but they preserved the similar segmental reorientation sequence under the single-task condition. For the healthy controls, attentional loading led to an earlier axial segment reorientation, but the reorientation sequence was preserved. In contrast, the dual-cognitive task condition led to a disrupted reorientation sequence in stroke. The results indicate that turning coordination was altered in individuals poststroke, especially under the dual-task interference.

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Victoria H. Stiles, Igor N. Guisasola, Iain T. James and Sharon J. Dixon

Integrated biomechanical and engineering assessments were used to determine how humans responded to variations in turf during running and turning. Ground reaction force (AMTI, 960 Hz) and kinematic data (Vicon Peak Motus, 120 Hz) were collected from eight participants during running (3.83 m/s) and turning (10 trials per condition) on three natural turf surfaces in the laboratory. Surface hardness (Clegg hammer) and shear strength (cruciform shear vane) were measured before and after participant testing. Peak loading rate during running was significantly higher (p < .05) on the least hard surface (sandy; 101.48 BW/s ± 23.3) compared with clay (84.67 BW/s ± 22.9). There were no significant differences in running kinematics. Compared with the “medium” condition, fifth MTP impact velocities during turning were significantly (RM-ANOVA, p < .05) lower on clay (resultant: 2.30 m/s [± 0.68] compared with 2.64 m/s [± 0.70]), which was significantly (p < .05) harder “after” and had the greatest shear strength both “before” and “after” participant testing. This unique finding suggests that further study of foot impact velocities are important to increase understanding of overuse injury mechanisms.

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Daniel J. Daly, Laurie A. Malone, David J. Smith, Yves Vanlandewijck and Robert D. Steadward

A video race analysis was conducted at the Atlanta Paralympic Games swimming competition. The purpose was to describe the contribution of clean swimming speed, as well as start, turn, and finish speed, to the total race performance in the four strokes for the men’s 100 m events. Start, turn, and finish times, as well as clean swimming speed during four race sections, were measured on videotapes during the preliminary heats (329 swims). Information on 1996 Olympic Games finalists (N = 16) was also available. In Paralympic swimmers, next to clean swimming speed, both turning and finishing were highly correlated with the end race result. Paralympic swimmers do start, turn, and finish slower than Olympic swimmers but in direct relation to their slower clean swimming speed. The race pattern of these components is not different between Paralympic and Olympic swimmers.

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Stephen M. Gavazzi

This paper examines the incentive-based system of Urban Meyer, head football coach at The Ohio State University. Personal discussions with this coach and members of his football staff took place following a review of his methods as described in biographical and media reports, and were compared with the approaches used by other successful coaches as documented in coaching research. Meyer has created clear guidelines and expectations for behaviors that players must consistently display to be recognized as successful team members and leaders. He also has developed a comprehensive set of processes to promote the development and adherence to those desired behaviors. This examination of Meyer’s approach focuses on the connection between the three levels (Blue, Red and Gold) of his incentive-based system and the three phases of a rite of passage (separation, transformation, and reincorporation) associated with them. The system rewards more grownup behaviors with greater status and privileges befitting the increasingly mature individual. A case is made that coaches can employ such a rites of passage framework as part of a comprehensive philosophy about turning boys into men, thus encouraging successful outcomes both on and off the field.

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John Heil

Edited by Adam Naylor