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Masafumi Terada, Megan Beard, Sara Carey, Kate Pfile, Brian Pietrosimone, Elizabeth Rullestad, Heather Whitaker and Phillip Gribble

activity levels ( Hubbard-Turner & Turner, 2015 ), and may accelerate the onset of posttraumatic ankle osteoarthritis ( Golditz et al., 2014 ; Valderrabano, Hintermann, Horisberger, & Fung, 2006 ). There is a subset of individuals categorized as LAS copers who, upon suffering an initial LAS, do not

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Robert C. Eklund, J. Robert Grove and N. Paul Heard

The purpose of this investigation was to evaluate four psychometric models for Carver, Scheier, and Weintraub’s (1989) COPE inventory, and for Crocker and Graham’s (1995) sport-specific modification of the COPE inventory for measurement of individual differences in coping with sport-related stress. Slumping athletic performance (i.e., an extended, unexplained loss of competitive form) was employed as the frame of reference for the coping responses. Data collected from 1,491 athletes (870 for the COPE analyses and 621 for the Modified-COPE analyses) were evaluated in the empirical, double cross-validation design analyses (Cudeck & Browne, 1983). Results revealed a 14-factor model of the COPE inventory and a 10-factor model of the Modified-COPE inventory as the most appropriate psychometric models for these inventories in examining slump-related coping among athletes.

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Alan R. Needle, Thomas W. Kaminski, Jochen Baumeister, Jill S. Higginson, William B. Farquhar and C. Buz Swanik

Context:

Rolling sensations at the ankle are common after injury and represent failure in neural regulation of joint stiffness. However, deficits after ankle injury are variable and strategies for optimizing stiffness may differ across patients.

Objective:

To determine if ankle stiffness and muscle activation differ between patients with varying history of ankle injury.

Patients:

Fifty-nine individuals were stratified into healthy (CON, n = 20), functionally unstable (UNS, n = 19), and coper (COP, n = 20) groups.

Main Outcome Measures:

A 20° supination perturbation was applied to the ankle as position and torque were synchronized with activity of tibialis anterior, peroneus longus, and soleus. Subjects were tested with muscles relaxed, while maintaining 30% muscle activation, and while directed to react and resist the perturbation.

Results:

No group differences existed for joint stiffness (F = 0.07, P = .993); however, the UNS group had higher soleus and less tibialis anterior activation than the CON group during passive trials (P < .05). In addition, greater early tibialis anterior activation generally predicted higher stiffness in the CON group (P ≤ .03), but greater soleus activity improved stiffness in the UNS group (P = .03).

Conclusion:

Although previous injury does not affect the ability to stiffen the joint under laboratory conditions, strategies appear to differ. Generally, the COP has decreased muscle activation, whereas the UNS uses greater plantar-flexor activity. The results of this study suggest that clinicians should emphasize correct preparatory muscle activation to improve joint stiffness in injury-rehabilitation efforts.

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Daniel Gould, Eileen Udry, Dana Bridges and Laurie Beck

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Sondra G. Siegel, T. Richard Nichols and Timothy C. Cope

Cutaneous reflexes have been described primarily according to their actions in the flexion/extension plane. It is shown here, by measuring electromyography and isometric force in decerebrate cats, that ankle muscles are activated in relation to their actions in the abduction/adduction plane during sural nerve (SNR) and crossed-extension (XER) reflexes. Ankle adductors (tibialis posterior, extensor digitorum longus, and flexors digitorum and hallucis longus) were active in XER, but not in SNR. Muscles producing ankle abduction (medial and lateral gastrocnemii and peroneus longus and brevis) were often activated in both reflexes, and medial gastrocnemius and peroneus longus were consistently more strongly activated in SNR than in XER. This differential pattern of muscle activation results in greater abduction torque at the ankle in SNR than in XER. These data demonstrate reflex organization in relation to the multidirectional torque generated by individual muscles.

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Yong Tai Wang, Randy Bernard, Clint Cope, Li-Shan Chang, Weerawat Limroongreungrat and Stephen Sprigle

This study examined time efficiency in wheelchair locomotive activities among four different wheelchairs propelled by elders with arms and/or legs. Sixteen elder manual wheelchair users propelled her/his own wheelchair and three wheelchairs (the main drive-axis wheels positioning in front, middle, and rear, respectively) in the test of seven wheelchair locomotive activities of daily living. A Mixed-Model ANOVA and Bonferroni post hoc test (p < .05) were employed to determine the time efficiency among four wheelchairs and three groups. The results demonstrated better time efficiency resulted from propelling the mid drive-axis and/or rear drive-axis wheelchairs; using arms and legs simultaneously propelling wheelchairs was more time efficient than using the arms or legs only in the selected locomotive activities.

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Alan J. Sokoloff, Timothy C. Cope, T. Richard Nichols and Arthur W. English

Differences in the directions of torque produced by motor units might be used by the nervous system to coordinate posture and movement. Here we report plantar flexion and abduction isometric torques exerted at the ankle by 158 motor units in the cat medial gastrocnemius (MG) muscle. In five cats, motor unit torque direction differed by an average of 10°. Torque direction was weakly correlated with unit contraction time in 3 of 5 experiments, with tetanic force in 3 of 5 experiments, and with conduction velocity in 1 of 5 experiments. The direction of whole muscle torque, however, was constant at all levels of MG activation produced in sural and crossed extension reflexes. Thus, although there is a range in the direction of torque produced by motor units in the cat MG, we find no evidence for the ordering of motor units according to torque direction during MG activation.

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Christina Jones, Kyle B. Kosik, Phillip Gribble and Matthew C. Hoch

plantar cutaneous sensation compared to ankle sprain copers or individuals with no history of ankle sprain? Search Strategy A computerized search was completed in July 2019. The search terms used were: • (chronic ankle instability OR functional ankle instability OR mechanical ankle instability OR ankle

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Chantelle Zimmer, Janice Causgrove Dunn and Nicholas L. Holt

experiences in physical education were especially negative. Psychological stress is commonly viewed as an experience that arises when there is a mismatch between a person’s perceptions of a situation and his or her resources to cope with environmental demands ( Aldwin, 2007 ; Lazarus & Folkman, 1984

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Sebastian Altfeld, Paul Schaffran, Jens Kleinert and Michael Kellmann

how to manage and cope with media reporting in press and social networks. Inconsistency Between Efforts and Rewards Coaches must cope with significant stress. Despite high volatility in employment, external pressures to win, including the media, they have to invest extensive time in preparing