This study evaluated the performance of 6 commercially available hard hat designs—differentiated by shell design, number of suspension points, and suspension tightening system—in regard to their ability to attenuate accelerations during vertical impacts to the head. Tests were conducted with impactor materials of steel, wood, and lead shot (resembling commonly seen materials in a construction site), weighing 1.8 and 3.6 kg and dropped from 1.83 m onto a Hybrid III head/neck assembly. All hard hats appreciably reduced head acceleration to the unprotected condition. However, neither the addition of extra suspension points nor variations in suspension tightening mechanism appreciably influenced performance. Therefore, these results indicate that additional features available in current hard hat designs do not improve protective capacity as related to head acceleration metrics.
Arthur Alves Dos Santos, James Sorce, Alexandra Schonning, and Grant Bevill
Jeff M. Barrett, Colin D. McKinnon, Clark R. Dickerson, and Jack P. Callaghan
Relatively few biomechanical models exist aimed at quantifying the mechanical risk factors associated with neck pain. In addition, there is a need to validate spinal-rhythm techniques for inverse dynamics spine models. Therefore, the present investigation was 3-fold: (1) the development of a cervical spine model in OpenSim, (2) a test of a novel spinal-rhythm technique based on minimizing the potential energy in the passive tissues, and (3) comparison of an electromyographically driven approach to estimating compression and shear to other cervical spine models. The authors developed ligament force–deflection and intervertebral joint moment–angle curves from published data. The 218 Hill-type muscle elements, representing 58 muscles, were included and their passive forces validated against in vivo data. Our novel spinal-rhythm technique, based on minimizing the potential energy in the passive tissues, disproportionately assigned motion to the upper cervical spine that was not physiological. Finally, using kinematics and electromyography collected from 8 healthy male volunteers, the authors calculated the compression at C7–T1 as a function of the head–trunk Euler angles. Differences from other models varied from 25.5 to 368.1 N. These differences in forces may result in differences in model geometry, passive components, number of degrees of freedom, or objective functions.
Bryony Buck, Scott Beveridge, Gerard Breaden Madden, and Hans-Christian Jabusch
Background: High-speed drumming requires precise control over the timing, velocity, and magnitude of striking movements. Aim: To examine effects of tempo and expertise on unaccented repetitive drumming performance using 3D motion capture. Methods: Expert and amateur drummers performed unimanual, unaccented, repetitive drum strikes, using their dominant right hand, at five different tempi. Performance was examined with regard to timing variability, striking velocity variability, the ability to match the prescribed tempo, and additional variables. Results: Permutated multivariate analysis of variance (PERMANOVA) revealed significant main effects of tempo (p < .001) and expertise (p <.001) on timing variability and striking velocity variability; low timing variability and low striking velocity variability were associated with low/medium tempo as well as with increased expertise. Individually, improved precision appeared across an optimum tempo range. Precision was poorest at maximum tempo (400 hits per minute) for precision variables. Conclusions: Expert drummers demonstrated greater precision and consistency than amateurs. Findings indicate an optimum tempo range that extends with increased expertise.
Kristen M. Stearns-Reider, Rachel K. Straub, and Christopher M. Powers
Peak knee valgus has been shown to predict anterior cruciate ligament injury. The purpose of the current study was to compare peak rate of torque development (RTD) to peak isometric torque as a predictor of peak knee valgus during landing. Twenty-three healthy females participated. Hip abductor muscle performance was quantified using 2 types of isometric contractions: sustained and rapid. Peak isometric torque was calculated from the sustained isometric contraction. Peak RTD was calculated from the rapid isometric contraction (0–50 and 0–200 ms after force initiation). Kinematic data were collected during the deceleration phase of a double-leg drop jump task. Linear regression was used to assess the ability of hip abductor muscle performance variables to predict peak knee valgus. Increased peak RTD during the 0 to 50 milliseconds window after force initiation was found to significantly predict lower peak knee valgus (P = .011, R 2 = .32). In contrast, neither peak RTD from 0 to 200 milliseconds after force initiation window (P = .45, R 2 = .03) nor peak isometric torque (P = .49, R 2 = .03) predicted peak knee valgus. The inability of the hip abductors to rapidly generate muscular force may be more indicative of “at-risk” movement behavior in females than measures of maximum strength.
ZáNean McClain, Erin Snapp, Daniel W. Tindall, and Jill Anderson
Philip Sullivan and Laura Tennant
Intercollegiate student-athletes appear to be a high-risk population with respect to mental health. Student athletic therapists are one of the groups with whom these athletes may be comfortable disclosing concerns. The current study investigated the relationship between mental health literacy and mental health referral efficacy in a sample of intercollegiate student therapists. One hundred and eleven student athletic therapists (81 female, 29 male, 1 nondiscloure) competed a revised version of the multicomponent mental health literacy measure and a four-item measure of mental health referral efficacy. T tests revealed statistically significant differences in mental health literacy by gender and personal history, and a multiple linear regression revealed a significant model predicting referral efficacy from mental health literacy. There are several implications of these results, particularly when working with a high-risk population of student-athletes.
Andreas Kuettel, Natalie Durand-Bush, and Carsten H. Larsen
The purpose of this study was (a) to investigate gender differences in mental health among Danish youth soccer players, (b) to discover the mental health profiles of the players, and (c) to explore how career progression and mental health are related. A total of 239 Danish youth elite soccer players (M = 16.85, SD = 1.09) completed an online questionnaire assessing mental well-being, depression, anxiety, along with other background variables. Female players scored significantly lower on mental well-being and had four times higher odds of expressing symptoms of anxiety and depression than males. Athletes’ mental health profiles showed that most athletes experience low depression while having moderate mental well-being. Depression, anxiety, and stress scores generally increased when progressing in age, indicating that the junior–senior transition poses distinct challenges to players’ mental health, especially for female players. Different strategies to foster players’ mental health depending on their mental health profiles are proposed.
Eleftherios Paraskevopoulos, Georgios Gioftsos, Georgios Georgoudis, and Maria Papandreou
Adherence to exercise rehabilitation has been shown to be an important factor that may influence successful treatment. In professional athletes, a significant reduction in exercise adherence delays recovery. The aim of this study was to explore barriers to and facilitators of exercise rehabilitation adherence in injured volleyball athletes. Eight professional volleyball athletes were recruited, and qualitative data were collected using semistructured interviews. All athletes had completed their rehabilitation program after they had suffered a musculoskeletal injury. All data were analyzed using thematic analysis after the investigators ensured that saturation had been reached. Pain was identified as a significant barrier to exercise adherence by all athletes. The provision of social support, including mental, practical, and task related, also had a significant positive impact. The athletes’ ability to develop the necessary coping strategies and confidence on performing exercises at home was also mentioned as a factor that affected exercise adherence, although less often.
Benjamin J.I. Schellenberg, Jérémie Verner-Filion, and Patrick Gaudreau
Athletes can respond to positive experiences in sport by engaging in savoring—that is, by attempting to prolong or amplify their positive feelings. In this research, the authors tested if savoring was predicted by levels of harmonious or obsessive passion for sport and if savoring was associated with symptoms of burnout. In Study 1 (n = 499), the authors found that savoring was positively associated with harmonious passion and negatively associated with obsessive passion. In addition, savoring predicted lower levels of burnout and played an indirect role in the relationship between both passion types and burnout. The authors replicated these findings in Study 2 (n = 298), with collegiate-level athletes, prospectively, over the course of a season. Overall, athletes with strong levels of harmonious passion appear to be most likely to engage in savoring, a response that may protect them from experiencing higher levels of burnout.
Christine E. Pacewicz and Alan L. Smith
Interpersonal exchanges may contribute to athletes’ motivational and well-being experiences through their contribution to athletes’ feelings of loneliness. Loneliness is understudied in sport, yet it is potentially salient in connecting social relationships with motivational processes and well-being of athletes. The purpose of the current research was to examine (a) the association of aspects of teammate relationships with athletes’ perceptions of burnout and engagement and (b) whether loneliness explained these associations. Adolescent athletes (N = 279) completed established measures of teammate relationships, loneliness, burnout, and engagement. The mediational model was invariant between boys and girls. Loneliness mediated the relationship of social support (β = −0.14, 0.10), corumination (β = 0.09, −0.06), and appraisal of peer rejection (β = 0.11, −0.08) with burnout and engagement, respectively. Continued examination of athletes’ loneliness will extend understanding of athletes’ motivational and well-being experiences and inform the promotion of adaptive sport experiences.