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Bin Chen, Lifen Liu, Lincoln Bin Chen, Xianxin Cao, Peng Han, Chenhao Wang and Qi Qi

Context: Measuring isometric shoulder rotational strength is clinically important for evaluating motor disability in athletes with shoulder injuries. Recent evidence suggests that handheld dynamometry may provide a low-cost and portable method for the clinical assessment of isometric shoulder strength. Objective: To investigate the concurrent validity and the intrarater and interrater reliability of handheld dynamometry for measuring isometric shoulder rotational strength. Design: Cross-sectional study. Setting: Biomechanics laboratory. Participants: Thirty-nine young, healthy participants. Main Outcome Measures: The peak isometric strength of the internal rotators and external rotators, measured by handheld dynamometry (in newton) and isokinetic dynamometry (in newton meter). Interventions: Maximal isometric shoulder rotational strength was measured as participants lay supine with 90° shoulder abduction, neutral rotation, 90° elbow flexion, and forearm pronation. Measurements were performed independently by 2 different physiotherapists and in 3 different sessions to evaluate interrater and intrarater reliability. The data obtained by handheld dynamometry were compared with those obtained by isokinetic testing to evaluate concurrent validity. Results: The intraclass correlation coefficients for interrater reliability in measuring maximum isometric shoulder external and internal rotation strength were .914 (95% confidence interval [CI], .842–.954) and .842 (95% CI, .720–.914), respectively. The intrarater reliability values of the method for measuring maximal shoulder external and internal rotation strength were 0.865 (95% CI, 0.757–0.927) and 0.901 (95% CI, 0.820–0.947), respectively. The Pearson correlation coefficients between the handheld and isokinetic dynamometer measurements were .792 (95% CI, .575–.905) for external rotation strength and .664 (95% CI, .419–.839) for internal rotation strength. Conclusions: The handheld dynamometer showed good to excellent reliability and moderate to good validity in measuring maximum isometric shoulder rotational strength. Therefore, handheld dynamometry could be acceptable for health and sports professionals in field situations to evaluate maximum isometric shoulder rotational strength.

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Noh Zulfikri, Victor S. Selvanayagam and Ashril Yusof

Context: Badminton continues to be a highly competitive sport where training is introduced at an early age and load has intensified. This exposes players to a greater risk of injuries, in particular when assessing related training outcomes such as strength, agonist–antagonist ratio, and bilateral deficit among adolescents where age- and sex-associated growth and development should be considered. Objective: To evaluate strength profile of the upper and lower limbs among adolescent elite Malaysian badminton players. Design: Cross-sectional study. Setting: Laboratory. Participants: Forty-eight asymptomatic athletes (24 males and 24 females) were grouped into early and late adolescence (13–14 y old and 15–17 y old, respectively). Main Outcome Measure(s): Strength (absolute and normalized) of the external/internal rotators of the shoulder and flexor/extensor of the knee and strength derivatives, conventional strength ratio (CSR), dynamic control ratio (DCR), and bilateral deficits were measured. Results: Males showed greater strength in all strength indices (P < .05). The older group had greater strength compared to younger for most of the upper and lower limb indices (P < .05); these effects diminished when using normalized data. For females, there was no age group effect in the shoulder and knee strength. All players displayed lower shoulder and knee normative values for CSR and DCR. Dominant and non-dominant knee strength were comparable between sex and age groups. Conclusions: For males, growth and maturation had a greater contribution to strength gained compared to training, whereas for females, growth, maturation, and training did not improve strength. The normalized data indicated that training did not improve all indices measured apart from external rotator strength in females. All players also displayed lower normative values of CSR and DCR. These results suggest that training in elite adolescent Malaysian badminton players lacks consideration of strength gain and injury risk factors.

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John F. Gaski

Over the past 3 decades or so, some variation and revision have been introduced into the recording, reporting, and interpretation of the prime historical benchmark of individual golf achievement: number of established major tournaments won. In the interest of accuracy, consistency, and even equity, some analytic record-keeping suggestions are proffered here, based on coherence and logic, toward presenting the history of golf’s major championships in the fairest possible way. Idiosyncrasies of that historical sequence mean that the resolution is not obvious and more taxonomic work remains to be done. However, acceptance of the principles and conventions proposed herein may move the golf history culture and even basic golf chronicling closer to advantageous closure. One competitive implication of this reanalysis applies, significantly, to the total of “majors” won by historical greats Jack Nicklaus, Bobby Jones, and Tiger Woods.

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Akira Saito, Kyoji Okada, Hiromichi Sato, Kazuyuki Shibata and Tetsuaki Kamata

Context: Baseball pitching is a coordinated movement involving the spine. A previous study indicated that increased thoracic kyphosis angle in a standing position was a risk factor for medial elbow injuries in youth baseball players. However, spinal alignments in single-leg standing and their relationships with medial elbow injuries, scapular alignment, or hip joint range of motion are unclear. Objective: To examine the difference in spinal alignment between standing and single-leg standing positions in youth baseball players and analyze their relationship with elbow injuries, scapular alignment, or hip joint range of motion. Design: Cross-sectional study. Setting: University laboratory. Participants: There were 51 youth baseball players with medial epicondylar fragmentation (medial elbow injury group) and 102 healthy youth baseball players (control group). Main Outcome Measures: Thoracic kyphosis, lumbar lordosis, and trunk inclination angles during standing and single-leg standing, forward scapular posture, and hip joint range of motion. Results: In the single-leg standing position, the thoracic kyphosis and backward trunk inclination angles were significantly higher in the medial elbow injury group than in the control group (P = .016 and P = .046, respectively). In the standing position, no significant difference was observed between both groups. The thoracic kyphosis angle in single-leg standing was positively correlated with the bilateral forward scapular posture in the medial elbow injury (P = .008 and P < .001 on the throwing and nonthrowing sides, respectively) and control (P = .010 and P = .032 on the throwing and nonthrowing sides, respectively) groups. Conclusions: High thoracic kyphosis and backward trunk inclination angles are characteristics during single-leg standing in youth baseball players with medial elbow injuries. Spinal alignment measurement in single-leg standing may be useful for identifying youth baseball players who are at risk for sustaining medial elbow injury.

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Jennifer A. Scarduzio, Christina S. Walker, Nicky Lewis and Anthony M. Limperos

This study examined how participants responded to incidents of athlete-perpetrated intimate partner violence in two separate contexts: one featuring an athlete from a league that is at peak popularity among sports audiences (National Football League; NFL) and one featuring an athlete from an up-and-coming league that currently has a lower standing in professional sports (Ultimate Fighting Championship League; UFC). The authors used the social ecological model to qualitatively analyze participant perceptions about athlete-perpetrated intimate partner violence composite news packages. For the purpose of this study specifically, they centered on 1,124 responses to one of the open-ended qualitative questions asked in a larger quantitative experiment. The authors found that the participants most frequently attributed the perpetrator’s behavior to either individual or relationship-level reasons and that there were differences in the level attributed for participants of different races and ethnicities. They also determined that the participants were more likely to ascribe the violence to the suspect’s job (i.e., athlete) if they were a UFC fighter than an NFL player. Theoretical extensions of the social ecological model and practical implications for journalists, the media, and fans are offered.

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Megan A. Kuikman, Margo Mountjoy, Trent Stellingwerff and Jamie F. Burr

Relative energy deficiency in sport (RED-S) can result in negative health and performance outcomes in both male and female athletes. The underlying etiology of RED-S is low energy availability (LEA), which occurs when there is insufficient dietary energy intake to meet exercise energy expenditure, corrected for fat-free mass, leaving inadequate energy available to ensure homeostasis and adequate energy turnover (optimize normal bodily functions to positively impact health), but also optimizing recovery, training adaptations, and performance. As such, treatment of RED-S involves increasing energy intake and/or decreasing exercise energy expenditure to address the underlying LEA. Clinically, however, the time burden and methodological errors associated with the quantification of energy intake, exercise energy expenditure, and fat-free mass to assess energy availability in free-living conditions make it difficult for the practitioner to implement in everyday practice. Furthermore, interpretation is complicated by the lack of validated energy availability thresholds, which can result in compromised health and performance outcomes in male and female athletes across various stages of maturation, ethnic races, and different types of sports. This narrative review focuses on pragmatic nonpharmacological strategies in the treatment of RED-S, featuring factors such as low carbohydrate availability, within-day prolonged periods of LEA, insufficient intake of bone-building nutrients, lack of mechanical bone stress, and/or psychogenic stress. This includes the implementation of strategies that address exacerbating factors of LEA, as well as novel treatment methods and underlying mechanisms of action, while highlighting areas of further research.

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Courtney M. Butowicz, Julian C. Acasio and Brad D. Hendershot

Altered trunk movements during gait in persons with lower-limb amputation are often associated with an increased risk for secondary health conditions; however, the postural control strategies underlying such alterations remain unclear. In this secondary analysis, the authors employed nonlinear measures of triplanar trunk accelerations via short-term Lyapunov exponents to investigate trunk local stability as well as spatiotemporal gait parameters to describe gait mechanics. The authors also evaluated the influence of a concurrent task on trunk local stability and gait mechanics to explore if competition for neuromuscular processing resources can assist in identifying unique strategies to control kinematic variability. Sixteen males with amputation—8 transtibial and 8 transfemoral—and 8 uninjured males (controls) walked on a treadmill at their self-selected speed (mean = 1.2 m/s ±10%) in 5 experimental conditions (8 min each): 4 while performing a concurrent task (2 walking and 2 seated) and 1 with no concurrent task. Individuals with amputation demonstrated significantly smaller Lyapunov exponents than controls in all 3 planes of motion, regardless of concurrent task or level of amputation (P < .0001). Individuals with transfemoral amputation walked with wider strides compared with individuals with transtibial amputation and controls (P < .0001). Individuals with amputation demonstrated more trunk kinematic variability in the presence of wider strides compared with individuals without amputation, and it appears that performing a concurrent cognitive task while walking did not change trunk or gait mechanics.

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Daniel Yang and Kathy Babiak

A specific form of corporate social responsibility—corporate philanthropy—has received little attention in sport scholarship despite the increased formalization of this business function in practice. Specifically, few studies have explored the institutional mechanisms that influence the corporate philanthropy of professional sport teams. Given that teams receive simultaneous institutional pressures from their league and from the community in which they operate, this study examined how the presence of multiple peers from different fields affected teams in terms of determining the appropriate level of philanthropic activity. The hypotheses were tested through a longitudinal analysis of philanthropic data from team foundations in four professional leagues in the United States from 2005 to 2017. The authors found that teams were more likely to be affected by the philanthropic giving levels of league peers than local peers. Overall, this study provides a better understanding of simultaneous institutional pressures shaping the philanthropic activities of professional sport teams.

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Xiyao Shan, Pavlos Evangelidis, Takaki Yamagishi, Shun Otsuka, Fumiko Tanaka, Shigenobu Shibata and Yasuo Kawakami

This study investigated (a) site- and direction-dependent variations of passive triceps surae aponeurosis stiffness and (b) the relationships between aponeurosis stiffness and muscle strength and walking performance in older individuals. Seventy-nine healthy older adults participated in this study. Shear wave velocities of the triceps surae aponeuroses at different sites and in two orthogonal directions were obtained in a prone position at rest using supersonic shear imaging. The maximal voluntary isometric contraction torque of the plantar flexors and normal (preferred) and fast (fastest possible) walking speeds (5-m distance) were also measured. The shear wave velocities of the adjoining aponeuroses were weakly associated with plantar flexion torque (r = .23–.34), normal (r = .26), and fast walking speed (r = .25). The results show clear spatial variations and anisotropy of the triceps surae aponeuroses stiffness in vivo, and the aponeurosis stiffness was associated with physical ability in older adults.