The purpose of this investigation was to elucidate whether ankle joint stretch-shortening cycle performance, isometric and isokinetic plantarflexion strength, and maximal Achilles tendon force and elongation differ between dancers, endurance runners, and untrained controls. To differentiate between dancers, endurance runners, and controls, the authors measured maximal Achilles tendon force and elongation during isometric ramp contractions with ultrasonic imaging, maximal isometric and isokinetic plantarflexion strength with dynamometry, and stretch-shortening cycle function during countermovement hopping and 30-cm drop hopping with a custom-designed sled. The Achilles tendon of dancers elongated significantly (P ≤ .05) more than runners and controls. Dancers were significantly stronger than controls during isometric contractions at different ankle angles. Concentric and eccentric strength during isokinetic contractions at 60°·s−1 and 120°·s−1 was significantly higher in dancers and runners than controls. Dancers hopped significantly higher than runners and controls during hopping tasks. Dancers also possessed significantly greater countermovement hop relative peak power, drop hop relative impulse, and drop hop relative peak power than controls. Finally, dancers reached significantly greater velocities during countermovement hops than runners and controls. Our findings suggest dancing and running require or likely enhance plantarflexion strength. Furthermore, dancing appears to require and enhance ankle joint stretch-shortening cycle performance and tendon elongation.
Paige E. Rice, Kiisa Nishikawa, Kevin A. Zwetsloot, Amelia S. Bruce, Caroline D. Guthrie, and Sophia Nimphius
Declan A. Patton, Colin M. Huber, Susan S. Margulies, Christina L. Master, and Kristy B. Arbogast
Field studies have evaluated the accuracy of sensors to measure head impact exposure using video analysis, but few have studied false negatives. Therefore, the aim of the current study was to investigate the proportion of potential false negatives in high school soccer head impact data. High school athletes (23 females and 31 males) wore headband-mounted Smart Impact Monitor-G impact sensors during competitive soccer games. Video footage from 41 varsity games was analyzed by 2 independent reviewers to identify head contact events, which were defined as visually observed contact to the head. Of the 1991 video-identified head contact events for which sensors were functioning and worn by the players, 1094 (55%) were recorded by the sensors. For female players, 45% of video-identified head contact events were recorded by the sensor compared with 59% for male players. For both females and males, sensitivity varied by impact mechanism. By quantifying the proportion of potential false negatives, the sensitivity of a sensor can be characterized, which can inform the interpretation of previous studies and the design of future studies using head impact sensors. Owing to the difficulty in obtaining ground truth labels of head impacts, video review should be considered a complementary tool to head impact sensors.
Jackie D. Zehr, Jessa M. Buchman-Pearle, Tyson A.C. Beach, Chad E. Gooyers, and Jack P. Callaghan
The relationship between internal loading dose and low-back injury risk during lifting is well known. However, the implications of movement parameters that influence joint loading rates—movement frequency and speed—on time-dependent spine loading responses remain less documented. This study quantified the effect of loading rate and frequency on the tolerated cumulative loading dose and its relation to joint lifespan. Thirty-two porcine spinal units were exposed to biofidelic compression loading paradigms that differed by joint compression rate (4.2 and 8.3 kN/s) and frequency (30 and 60 cycles per minute). Cyclic compression testing was applied until failure was detected or 10,800 continuous cycles were tolerated. Instantaneous weighting factors were calculated to evaluate the cumulative load and Kaplan–Meier survival probability functions were examined following nonlinear dose normalization of the cyclic lifespan. Significant reductions in cumulative compression were tolerated when spinal units were compressed at 8.3 kN/s (P < .001, 67%) and when loaded at 30 cycles per minute (P = .008, 45%). There was a positive moderate relationship between cumulative load tolerance and normalized cyclic lifespan (R 2 = .52), which was supported by joint survivorship functions. The frequency and speed of movement execution should be evaluated in parallel to loading dose for the management of low-back training exposures.
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.
Sara Oliveira, Marina Cunha, António Rosado, and Cláudia Ferreira
This study aimed to test a model that hypothesized that the compassionate coach, as perceived by the athletes, has an impact on athlete-related social safeness and psychological health, through shame and self-criticism. The sample comprised 270 Portuguese adult athletes, who practiced different competitive sports. The path analysis results confirmed the adequacy of the proposed model, which explained 45% of the psychological health’s variance. Results demonstrated that athletes who perceive their coaches as more compassionate tend to present higher levels of social safeness (feelings of belonging to the team) and of psychological health, through lower levels of shame and self-criticism. These novel findings suggest the importance of the adoption of supportive, warm, safe, and compassionate attitudes from coaches in athletes’ mental health. This study also offers important insights by suggesting that feelings of acceptance and connectedness in team relationships may be at the root of athletes’ emotional processes and well-being.
Michal Vágner, Zdeněk Bílek, Karel Sýkora, Vladimír Michalička, Lubomír Přívětivý, Miloš Fiala, Adam Maszczyk, and Petr Stastny
The aim of this study was to find the effect of holographic sight (HS) on short-distance shooting accuracy and precision during static and high-intensity dynamic actions. Twenty policemen (31 ± 2.2 years, 85.6 ± 6.1 kg, and 181.9 ± 4.4 cm) performed five shots in the 10-s limit under the static condition for 20 m and dynamic condition 15–5 m, and after 4 × 10 m sprint action, both with fixed sight (FS) and HS. The analysis of variance post hoc test revealed that HSstatic had higher shouting accuracy than FSstatic, FSdynamic, and HSdynamic (p = .03, p = .0001, and p = .0001, respectively) and FSdynamic had lower precision than FSstatic, HSstatic, and HSdynamic (p = .0003, p = .0001, and p = .01, respectively) in vertical sway. The HS for rifles has improved the accuracy of static shooting and vertical sway precision of dynamic shooting.
Julie R. Steele
Lisa Chaba, Stéphanie Scoffier-Mériaux, Fabienne d’Arripe-Longueville, and Vanessa Lentillon-Kaestner
This article focuses on two popular sports that can put male athletes at risk of developing an eating disorder: bodybuilding and running. Bodybuilders concentrate on gaining muscle mass and runners on leaning body mass. Based on the trans-contextual model of motivation, this study aimed to better understand the psychological mechanisms underlying eating disorders in these athletes. In all, 272 male bodybuilders and 217 male runners completed measures of sport motivation, theory of planned behavior variables (i.e., attitude, subjective norm, perceived behavioral control, and intention to gain muscle mass/lean body mass), and eating disorders (dieting, control, and bulimia behaviors). The results revealed satisfactory fit indices for both samples. Autonomous and controlled motivations for sport were positively directly and indirectly related to eating disorders in these athletes. This motivational mechanism needs more in-depth investigation, and motivational profiles might help distinguish athletes with and without eating disorders.
Jessica Murphy, Karen A. Patte, Philip Sullivan, and Scott T. Leatherdale
The mental health benefits of physical activity may relate more to the context of the behavior, rather than the behavior of being active itself. The association between varsity sport (VS) participation, depression, and anxiety symptoms was explored using data from 70,449 high school students from the Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior study. The model adjusted for potential covariates; interactions by sex and participation in outside of school sport (OSS) were explored. Overall, 70% and 24% of respondents met or exceeded cutoff values for depression and anxiety, respectively. Students participating in VS had lower symptoms of anxiety and depression compared with nonparticipants. Results were consistent regardless of OSS participation; associations were strongest among students who participated in both VS and OSS and males. Participation in VS may prove beneficial for the prevention and/or management of depression or anxiety symptoms, particularly among males. An additive beneficial effect of OSS on depression and anxiety scores may exist.