Investigating balance reactions following continuous, multidirectional, support surface perturbations is essential for improving our understanding of balance control in moving environments. Segmental motions are often incorporated into rapid balance reactions following external perturbations to balance, although the effects of these motions during complex, continuous perturbations have not been assessed. This study aimed to quantify the contributions of body segments (ie, trunk, head, upper extremity, and lower extremity) to the control of center-of-mass (COM) movement during continuous, multidirectional, support surface perturbations. Three-dimensional, whole-body kinematics were captured while 10 participants experienced 5 minutes of perturbations. Anteroposterior, mediolateral, and vertical COM position and velocity were calculated using a full-body model and 7 models with reduced numbers of segments, which were compared with the full-body model. With removal of body segments, errors relative to the full-body model increased, while relationship strength decreased. The inclusion of body segments appeared to affect COM measures, particularly COM velocity. Findings suggest that the body segments may provide a means of improving the control of COM motion, primarily its velocity, during continuous, multidirectional perturbations, and constitute a step toward improving our understanding of how the limbs contribute to balance control in moving environments.
Alison Schinkel-Ivy, Vicki Komisar, and Carolyn A. Duncan
Thomas D. Raedeke, Victoria Blom, and Göran Kenttä
This study evaluated the relationship of perfectionism and self-perceptions with burnout and life satisfaction in aesthetic performers (N = 254) recruited in Sweden. Cluster analysis revealed four groups: perfectionistic with maladaptive self-perceptions, perfectionistic (parent-driven) with maladaptive self-perceptions, achievement-oriented with adaptive self-perceptions, and nonperfectionistic with adaptive self-perceptions. Performers in both maladaptive clusters reported characteristics suggesting they were perfectionistic compared to their peers. They also reported relatively high contingent self-worth and low basic self-esteem. In contrast, those in the nonperfectionistic with adaptive self-perceptions cluster scored relatively low on perfectionism and reported relatively high basic self-esteem and low contingent self-worth. The performers in the achievement-oriented with adaptive self-perceptions cluster reported average scores across most variables, moderately high personal standards, and higher basic self-esteem compared with contingent self-worth. Overall, performers in both maladaptive clusters reported the highest burnout and lowest life satisfaction. Study findings underscore the importance of perfectionism and self-perceptions when considering burnout and life satisfaction.
Chantelle Zimmer, Janice Causgrove Dunn, and Nicholas L. Holt
Children with developmental coordination disorder (DCD) may experience stress in physical activity contexts due to emphasis on their poor motor skills. The purpose of this study was to explore the lived experiences of children at risk for DCD in physical education in order to develop a deeper understanding about what they experience as stress and how they cope with it. Using interpretative phenomenological analysis, six children in Grades 4–6 participated in two semistructured interviews. A motivational (and developmental) stress and coping theory informed interpretation of the three themes that described the children’s experiences: (a) they hurt me—psychological and physical harm sustained from peers, (b) it’s hard for me—difficulties encountered in activities, and (c) I have to—pressure to meet the teacher’s demands. Although the children at risk for DCD were confronted with various stressors in physical education, they coped more adaptively when social support was provided.
Willie Leung and Jeffrey A. McCubbin
Christopher J. Palmer and Richard E.A. van Emmerik
The purpose of this study was to assess the establishment of dynamic marksmanship performance under different load and postural configurations. Participants quickly established two postures (forward and high targets) under head, trunk, and extremity loads during marksmanship performance. With the dynamic establishment of posture, load disrupted coordinative dynamics, resulting in reduced speed and accuracy on target. Specifically, torso loads increased segmental variability while establishing posture, and smaller head and upper extremity loads extended quieting time before firing. Increased head extension at the high target further destabilized posture, with reduced accuracy across all loads. Large torso loads reduced the adaptability to modulate postural fluctuations at the foot center of pressure while establishing postures for marksmanship, as evidenced by reductions in center of pressure variability. This study expands traditional static marksmanship research, providing insight into relations between task performance, coordinative variability, and postural control while dynamically establishing precision postures.
Britton W. Brewer, Christine M. Caldwell, Albert J. Petitpas, Judy L. Van Raalte, Miquel Pans, and Allen E. Cornelius
A sport-specific, self-report measure of identity foreclosure was developed through a systematic process that included item pool generation, expert review, administration of items to a development sample of intercollegiate student athletes (N = 326), item evaluation, and administration of scales to validation samples of intercollegiate student athletes (N = 322, N = 54, and N = 64, respectively). The process yielded two four-item scales reflecting commitment to the occupational identity of athlete and one 4-item scale reflecting active exploration of roles other than that of athlete that (a) are internally consistent and temporally stable, (b) demonstrate preliminary factorial and convergent validity, and (c) can be used to create indices of identity foreclosure tailored to the sport context. The resulting Sport-Specific Measure of Identity Foreclosure has potential utility as an assessment tool for research and practice with athletes.
Ziva M. Rosker, Jernej Rosker, and Nejc Sarabon
Reports on body sway control following microdiscectomy lack reports on side-specific balance deficits as well as the effects of trunk balance control deficits on body sway during upright stances. About 3 weeks post microdiscectomy, the body sway of 27 patients and 25 controls was measured while standing in an upright quiet stance with feet positioned parallel on an unstable support surface, a tandem stance with the involved leg positioned in front or at the back, a single-leg stance with both legs, and sitting on an unstable surface. Velocity, average amplitude, and frequency-direction–specific parameters were analyzed from the center of pressure movement, measured by the force plate. Statistically significant differences between the 2 groups were observed for the medial–lateral body sway frequency in parallel stance on a stable and unstable support surface and for the sitting balance task in medial-lateral body sway parameters. Medium to high correlations were observed between body sway during sitting and the parallel stance, as well as between the tandem and single-legged stances. Following microdiscectomy, deficits in postural balance were side specific, as expected by the nature of the pathology. In addition, the results of this study confirmed the connection between proximal balance control deficits and balance during upright quiet balance tasks.
Nima Dehghansai, Daniel Spedale, Melissa J. Wilson, and Joseph Baker
Little is known about the factors influencing Paralympic athletes’ journey to expertise and whether these athletes have trajectories similar to those of their able-bodied (AB) peers. The purpose of this project was to compare the developmental trajectories of wheelchair and AB basketball players. A total of 150 participants completed the Developmental History of Athletes Questionnaire. Results revealed that while AB athletes reached early career milestones at a significantly younger age, athletes with congenital impairments reached midcareer milestones at similar ages to AB athletes. In addition, athletes with acquired impairments were able to reach key late-career performance milestones (i.e., national and international debuts) at a similar age to the other two groups. The findings from this study suggest complex developmental pathways that may not be reflected in current developmental models. Therefore, the authors suggest that scientists and practitioners be cognizant of context-specific needs when providing training recommendations.