Decreased dorsiflexion range of motion (DROM) can be modified using static stretching and joint mobilizations and may attenuate known knee anterior cruciate ligament injury risk factors. It is not known how these interventions compare to each other and how they improve knee landing mechanics. This study’s purpose was to determine the immediate effects of static stretching and joint mobilization interventions on DROM measurement changes and right-leg drop jump knee landing mechanics. Eighteen females and 7 males, all recreationally active, completed 2 study sessions. Active and passive DROM, the weight-bearing lunge test, the anterior reach portion of the Star Excursion Balance Test, and a right-leg drop jump landing task were completed before and after the intervention. Change in DROM (ΔDROM) was calculated for DROM assessments between preintervention and postintervention. Pairwise dependent t tests determined no differences in ΔDROM between interventions, and statistical parametric mapping determined increased knee flexion (P = .004) and decreased anterior shear force (P = .015) during landing after both interventions. Increased DROM improves sagittal plane displacement and loading at the knee. Stretching may be a more feasible option in a healthy population for those wanting to maintain range of motion and decrease knee injury risk without physical therapist involvement.
Lauren E. Schroeder, Rachel L. Tatarski, and Joshua T. Weinhandl
S. Sofie Lövdal, Ruud J.R. Den Hartigh, and George Azzopardi
Purpose: Staying injury free is a major factor for success in sports. Although injuries are difficult to forecast, novel technologies and data-science applications could provide important insights. Our purpose was to use machine learning for the prediction of injuries in runners, based on detailed training logs. Methods: Prediction of injuries was evaluated on a new data set of 74 high-level middle- and long-distance runners, over a period of 7 years. Two analytic approaches were applied. First, the training load from the previous 7 days was expressed as a time series, with each day’s training being described by 10 features. These features were a combination of objective data from a global positioning system watch (eg, duration, distance), together with subjective data about the exertion and success of the training. Second, a training week was summarized by 22 aggregate features, and a time window of 3 weeks before the injury was considered. Results: A predictive system based on bagged XGBoost machine-learning models resulted in receiver operating characteristic curves with average areas under the curves of 0.724 and 0.678 for the day and week approaches, respectively. The results of the day approach especially reflect a reasonably high probability that our system makes correct injury predictions. Conclusions: Our machine-learning-based approach predicts a sizable portion of the injuries, in particular when the model is based on training-load data in the days preceding an injury. Overall, these results demonstrate the possible merits of using machine learning to predict injuries and tailor training programs for athletes.
Ahalee C. Farrow and Ty B. Palmer
This study aimed to examine the effects of age on hip flexion maximal and rapid strength and rectus femoris (RF) muscle size and composition in men. Fifteen young (25  y) and 15 older (73  y) men performed isometric hip flexion contractions to examine peak torque and absolute and normalized rate of torque development (RTD) at time intervals of 0 to 100 and 100 to 200 milliseconds. Ultrasonography was used to examine RF muscle cross-sectional area and echo intensity. Peak torque, absolute RTD at 0 to 100 milliseconds, and absolute and normalized RTD at 100 to 200 milliseconds were significantly lower (P = .004–.045) in the old compared with the young men. The older men exhibited lower cross-sectional area (P = .015) and higher echo intensity (P = .007) than the young men. Moreover, there were positive relationships between cross-sectional area and absolute RTD at 0 to 100 milliseconds (r = .400) and absolute RTD at 100 to 200 milliseconds (r = .450) and negative relationships between echo intensity and absolute RTD at 100 to 200 milliseconds (r = −.457) and normalized RTD at 100 to 200 milliseconds (r = −.373). These findings indicate that hip flexion maximal and rapid strength and RF muscle size and composition decrease in old age. The relationships observed between ultrasound-derived RF parameters and measurements of RTD suggest that these age-related declines in muscle size and composition may be relevant to hip flexion rapid torque production.
Georde Vuillermin, Kelly-Ann Bowles, Ross Iles, and Cylie Williams
Health professionals responsible for return to work plans have little data about allied health movement to guide recommendations following lower back injury. This study aimed to quantify the lumbar movement patterns of allied health professionals within a health care facility throughout a normal workday. An observational case study was undertaken at a public health care facility with 122 allied health professionals. The lumbar movements were recorded with the ViMove together with pain scale measurement. The mean (SD) recording time for allied health was 7.7 (0.7) hours. A mean (SD) 3 (1.4) hours total were spent in standing, 3.8 (1.7) hours in sitting, and 0.8 (0.4) hours in locomotion. Forty-nine flexions were recorded on average per session, most identified as short term (<30 s) within low range (0°–20°). Lumbar movement patterns differed among professions. Thirty-seven (31%) participants reported a history of lower back injury, and 57 (47%) reported low back pain at the end of their workday. This study provides an insight into allied health professionals’ back movement in a hospital or community-based health care setting. These data may inform those who make return to work recommendations or provide rehabilitation services for allied health professionals working with a lower back injury.
Wen-Yen Tseng, Ghazi Rekik, Chia-Hui Chen, Filipe M. Clemente, Pedro Bezerra, Zachary J. Crowley-McHattan, and Yung-Sheng Chen
Background: The psychological and physiological adaptations in response to the FIFA 11+ for kids (FIFA11+kid) program has not been examined in school children. This study aimed to investigate the effects of 8-week FIFA11+kid intervention on physical fitness and attentional capacity in elementary school children. Methods: A total of 55 elementary school students voluntarily participated in the study. Participants were assigned to either the FIFA11+kid (n = 28, 5 times per week) or the control (n = 27) group. At baseline and after 8 weeks, all participants were asked to perform a battery of physical fitness tests (sit-and-reach, broad jump, sit-up test, and 800-m run) and the Attention Scale for Elementary School Children, including 5 subscales: focused, sustained, selective, alternating, and divided attentions. Results: The FIFA11+kid group demonstrated larger pre–post change in sit-and-reach (P < .001) and sit-up test (P < .001) than that of control group. Moreover, the FIFA11+kid group demonstrated large improvements pre–post change in Attention Scale for Elementary School Children scores of total score (P < .001), focused (P < .001), sustained (P < .001), and selective attentions (P < .001) compared with the control group. Conclusion: A total of 8 weeks of FIFA11+kid exercise intervention can improve general physical fitness and attentional capacities in elementary school children.
Margo E.K. Adam, Abimbola O. Eke, and Leah J. Ferguson
Self-compassion, an adaptive self-attitude, is a resource that women athletes use during emotionally difficult times and as a way to reach their potential. The relationship between self-compassion and sport performance, however, is complex. The role and experience of self-compassion within perceived important competitive events are important to explore, as athletes face unique pressures and stressors in these meaningful sport experiences. This collective case study describes women athletes’ self-compassion, sport performance perceptions, and well-being around a self-identified important competitive event. Competitive women athletes (N = 9) participated in two one-on-one interviews, before and after their important competitive event. Results from the holistic, functional, and thematic analyses are represented by holistic case descriptions and an overarching theme, Continuing to Excel in Sport, and subthemes, Reframing Criticism and A Determined Approach. In important competitive events, women athletes utilize self-compassion to promote performance perceptions and well-being when preparing, competing, and reflecting to excel in sport.
Myungjin Jung, Heontae Kim, Seungho Ryu, and Minsoo Kang
Background: The objective of this study was to evaluate secular trends in domain-specific physical activity in the immigrant population in the US between 2009 and 2018. Method: A secondary data analysis from the 2009–2018 National Health and Nutrition Examination Survey; a total of 7282 immigrants in the US were included in this analysis. All domain-specific physical activity was assessed by a self-reported questionnaire. Tests for linear trends were performed to examine the trends of each physical activity time using orthogonal polynomial coefficients. Physical activity trends were assessed by the whole group and the various subgroups. Results: Total physical activity showed an upward linear trend in female (P trend = .04) and young adult (P trend = .009) immigrants. Work-related physical activity showed an upward linear trend in young adult immigrants (P trend = .01). Recreational physical activity showed an upward linear trend in young adult (P trend = .03) and Mexican American (P trend < .001) immigrants and in immigrants living in the US for 15–29 years (P trend = .02). In contrast, we observed downward linear trends in transit-related physical activity for immigrants across male (P trend = .04), middle-aged adult (P trend = .01), and non-Hispanic black groups (P trend = .004) and in immigrants living in the US for 15–29 years (P trend = .03). Conclusion: There were no significant linear trends in the 4 domains of physical activity in the overall US immigrant population; however, trends in domain-specific physical activity in the US immigrant population differed by gender, age, race/ethnicity, and length of residence. These findings may inform physical activity promotion strategies targeting US immigrant populations with diverse sociocultural backgrounds.
Danielle S. Molnar, Melissa Blackburn, Dawn Zinga, Natalie Spadafora, Tabitha Methot-Jones, and Maureen Connolly
This study provided the first test of the 2 × 2 model of perfectionism with respect to dancers’ goals for dancing in competitive dance. Four hundred twenty-five young female North American competitive dancers (M = 11.33 years; SD = 2.14) completed questionnaires assessing multidimensional perfectionism and goals for participation in dance. The latent moderated structural equations approach along with procedures outlined by Gaudreau indicated partial support for the 2 × 2 model of perfectionism. Pure Evaluative Concerns Perfectionism was associated with fewer intrinsic goals for dance and greater extrinsic goals for dance relative to nonperfectionism. Pure Personal Standards Perfectionism was related to less endorsement of extrinsic goals relative to nonperfectionism. Findings were complex with respect to mixed perfectionism, with this form of perfectionism being related to greater endorsement of both intrinsic and extrinsic goals for dance. Results provide partial support for the 2 × 2 model in youth dance.