The effect of complex contrast training with different training frequency on the physical performance of youth soccer players: a randomized study.

Background: Complex contrast training (CCT) is potentially an efficient method to improve physical abilities such as muscle strength, power output, speed, agility, are extremely important in developing soccer players of different age categories. Aim: This study aimed to analyze the effects of 6 weeks of CCT program applied in different training frequency (sessions per week) on youth soccer players performance. Methods: Twenty-one youth soccer players (age: 15.3 ± 1.1 years; body mass 64.9 ± 0.7 kg; height 175.4 ± 0.7 cm) were randomized into three groups: a regular pre-season training control group (G0, n = 8), a group with regular pre-season training plus twice-a-week CCT (G2, n = 6), and a group with regular pre-season training plus thrice-a-week CCT (G3, n = 7). The CCT consisted of soccer skills-based exercises distributed across five stations, to be performed before common regular practice during a 6-week pre-season period. The agility (505 Agility test), sprint (S5 and S15), jump (SJ and CMJ), and free kick speed (11 m from the goal) of the groups were analyzed pre- and post-CCT intervention. During a 6-week pre-season period, the players integrated CCT into their regular training sessions. Furthermore, performance variables were compared between the groups. Results: A statistical difference was identified for the timepoint for the players' CMJ (p = 0.023; η2 = 0.343) and the free kick speed (p = 0.013; η2 = 0.383) using ANOVA. The G3 showed a significant improvement in the CMJ (p = 0.001) and the free kick speed (p = 0.003) between pre- to post-CCT test. No other significant changes in performance were observed (p > 0.05). Conclusion: The CCT training program with a weekly frequency of 3 days per week is effective in improving free kick speed and CMJ performance in young male soccer players (U-15 and U-17 categories). CCT training programs have the potential to refine an athlete's preparation for competition. However, certain performance tests did not demonstrate substantial enhancements. Consequently, additional investigations are required to ascertain the effectiveness of CCT.

The Influence of the COVID-19 Pandemic on Baseline Concussion Symptom Assessments Among Adolescents.

Introduction The COVID-19 pandemic resulted in the cancellation of high school sports in spring 2020, a modified resumption of sports in the 2020-2021 academic year, and a return to pre-pandemic sports in 2021-2022. This cancellation had a major impact on the quality of life of adolescent athletes, but it is unknown exactly how these pandemic-driven sports disruptions on athlete baseline (preseason) symptoms affected quality of life. Therefore, the current study retrospectively evaluated symptom inventories from Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) assessments to determine whether the cancellation of sports during the COVID-19 pandemic affected baseline (preseason) self-reported symptoms among adolescent athletes. Methods Our study used a retrospective cohort design to evaluate high school athletes with complete ImPACT assessments in the academic years before (2018-2019 and 2019-2020), during (2020-2021), and after (2021-2022) the pandemic. Specifically, data from a 22-item symptom report called the Post-Concussion Symptom Scale (PCSS) assessed during ImPACT was collected and analyzed using generalized linear models with a Tweedie exponential dispersion model and post hoc Tukey's honestly significant difference tests. The main outcomes were the total symptom severity score and the affective cluster score. Secondary outcomes were the analysis of the vestibular-somatic, cognitive-sensory, and sleep-arousal symptom clusters. Results Of the 104,274 ImPACT assessments, the total symptom severity score on the PCSS was different across years (p<0.001). There were lower symptom scores in 2020-2021 (5.33, 95% CI = 5.13-5.54) than in 2018-2019 (6.82, 95% CI = 6.63-7.01), 2019-2020 (6.94, 95% CI = 6.75-7.14), and 2021-2022 (6.44, 95% CI = 6.25-6.64). The cluster scores on the PCSS for affective, cognitive-sensory, sleep-arousal, and vestibular-somatic were also lower (p<0.001) in 2020-2021 than in 2018-2019, 2019-2020, and 2021-2022. Conclusion Contrary to our expectations, total symptom severity and cluster scores on the PCSS during the pandemic (2020-2021) were significantly lower than during the years before and after the pandemic-driven sports disruptions, suggesting the pandemic did not negatively affect these athletes as expected. These results also suggested that self-reported symptoms utilized in the PCSS component of ImPACT may not be as sensitive to sports disruption among adolescent athletes as other quality-of-life measures, especially during the COVID-19 pandemic.

Development and validation of an overuse injury questionnaire for youth athletes: The Youth Overuse Injury Questionnaire.

OBJECTIVE: To develop and validate the Youth Overuse Injury Questionnaire (YOvIQ). DESIGN: A cross-sectional study. SETTING: Online platforms. PARTICIPANTS: Two content experts (in sports injury epidemiology and in sports science and medicine) and seven end-users (youth volleyball athletes) provided feedback during development of the YOvIQ. 227 competitive youth athletes across 14 different sports assessed the psychometric properties of the YOvIQ. MAIN OUTCOME MEASURES: Participants completed both YOvIQ and the Oslo Sports Trauma Research Centre Overuse Injury Questionnaire (OSTRC-O2) for anatomical areas of the shoulder, elbow, lower back, knee, and ankle/foot. Validity was assessed via convergent validity. Reliability was assessed using internal consistency estimation and interclass correlation coefficient. RESULTS: Following feedback from content experts, examples and quantitative symbolization were added to the options in YOvIQ, with positive feedback from end-users. Convergent validity between YOvIQ and the OSTRC-O2 was demonstrated with non-significant differences (P ≥ .05) and significant correlations (P < 0.001) for prevalence and severity scores. YOvIQ demonstrated internal consistency for prevalence (Cronbach's alpha coefficient >0.70) and moderate-to-good reliability for severity scores (ICC: 0.51 to 0.88) for shoulder, lower back, and knee. CONCLUSIONS: The YOvIQ is a valid and reliable instrument to identify overuse injuries to the shoulder, lower back, and knee in youth athletes.

Suture Anchor Repair for Distal Patellar Tendon Avulsion in Tibial Tubercle Fractures: A Technical Description and Report of Two Cases.

Tibial tubercle avulsion fractures, though rare, pose a significant challenge in pediatric orthopedics, particularly in athletic adolescents. For nondisplaced fractures, conservative treatment involves the use of braces or casts, while displaced fractures necessitate operative intervention, often through screw fixation. Concomitant soft tissue injuries should also be identified and addressed operatively to ensure complete repair of the extensor mechanism. This paper introduces a method for open reduction and internal fixation (ORIF) of tibial tubercle fractures with suture anchor repair of the distal patellar tendon avulsion. Two case examples of 14-year-old males with displaced fractures undergoing this procedure are presented. After standard screw fixation of the displaced fragment was performed, a single suture anchor was placed into the tibia and an onlay tension slide technique was utilized to secure the distal patellar tendon avulsion. Both patients underwent immobilization and protected weightbearing for four weeks with physical therapy initiated at six weeks. At four months postoperatively, both patients had returned to competitive sports without issue. The described technique may represent a reliable and reproducible method for addressing the distal patellar tendon avulsion component of tibial tubercle fractures. Its biomechanical advantages contribute to the complete repair of the extensor mechanism, enabling a successful return to competitive athletics without hardware complications.

Physical activity, organized sport participation and active transportation to school among Canadian youth by gender identity and sexual attraction. / Activité physique, participation à des sports organisés et utilisation du transport actif pour se rendre à l'école chez les adolescents canadiens par identité de genre et par orientation sexuelle.

INTRODUCTION: Regular physical activity is associated with a wide range of health benefits in youth. While previous studies have identified disparities in physical activity among youth by gender identity and sexual attraction, these have seldom been explored in Canadian youth. METHODS: Data from the 2019 Canadian Health Survey on Children and Youth were used to assess prevalence of and time spent in organized sports participation, total physical activity and active transportation by gender identity (non-cisgender vs. cisgender) among youth aged 12 to 17, and by sexual attraction (nonheterosexual attraction vs. heterosexual attraction) among youth aged 15 to 17. RESULTS: There was no difference in average minutes of total physical activity per week between non-cisgender and cisgender Canadian youth. Non-cisgender youth (which represent 0.5% of the population) averaged significantly fewer minutes of organized sports per week than their cisgender counterparts. There was some evidence of increased active transportation to school among non-cisgender youth, but insufficient power to detect significant differences. Canadian youth reporting any nonheterosexual attraction (which represent 21.2% of the population, including mostly heterosexual youth) were less likely to be regularly physically active and participate in organized sports than youth reporting exclusive heterosexual attraction. Differences were larger among males than females. Males reporting nonheterosexual attraction were more likely to use active transportation to get to school than their heterosexual counterparts. CONCLUSION: Non-cisgender youth and youth reporting nonheterosexual attraction tended to participate less in organized sports than their counterparts, but may have engaged in more active transportation. Mitigating the barriers associated with sport participation could increase physical activity among these groups.

Effects of plyometric jump training on measures of physical fitness and lower-limb asymmetries in prepubertal male soccer players: a randomized controlled trial.

BACKGROUND: High level of physical fitness is a paramount soccer performance factor. As such, developing key components of physical fitness such as sprinting, jumping, and change of direction (CoD) at an early age empowers both short- and long-term performance success. Although previous research in prepubertal male soccer players has reported physical fitness performance enhancements following plyometric jump training (PJT), the effects on inter-limb asymmetries remain unclear. OBJECTIVE: To assess the effects of PJT on measures of physical fitness and inter-limb asymmetries in prepubertal male soccer players. METHODS: A total of 27 participants were recruited, and randomly assigned to either a PJT group (n = 13; age = 12.7 ± 0.2 years; maturity offset = -1.6 ± 0.7) or an active control group (CG) (n = 14; age = 11.8 ± 0.4 years; maturity offset = -2.51 ± 0.61). The training intervention lasted eight-week and was conducted during the in-season period, with twice-weekly sessions. Physical fitness tests were conducted before and after the intervention, including the 505 change-of-direction (CoD; [505 CoD test]), countermovement-jump (CMJ) height, standing-long-jump (SLJ) distance, and single-leg hop test for distance with dominant (SHTD-D) and non-dominant legs (SHTD-ND). A jump-based asymmetry score was calculated as the difference between HTD and HTND. RESULTS: ANCOVA analysis revealed significant between-group differences in all physical fitness measures at post-test. Specifically, the PJT group showed significant large improvements in CMJ height, SLJ distance, HTD and HTND, and CoD speed (d = 0.84 to 2.00; ∆1.05% to 16.85%). Moreover, the PJT group showed a significant, small reduction in the inter-limb asymmetry score (d = 0.43; ∆-45.21%). In contrast, no significant changes were reported in the CG between pre-and post-tests (d = 0.07 to 0.24; ∆0.21% to 0.98%). CONCLUSIONS: The incorporation of PJT into the training schedules of prepubertal male soccer players resulted in positive effects on various measures of physical fitness. Furthermore, our findings suggest that PJT can reduce lower-limb asymmetry, which could potentially decrease the risk of lower limb injuries. TRIAL REGISTRATION: This study does not report results related to healthcare interventions using human participants and therefore it was not prospectively registered.

Influence of body size and skeletal maturity status on strength and motor performances of soccer players 9-16 years.

The contributions of height, weight and skeletal age (SA) to strength and motor performances of male soccer players 9-12 (n = 60) and 13-16 (n = 52) years were estimated. SA was assessed with the Fels method, and was expressed as the standardized residual of the regression of SA on chronological age CA (SAsr). Static strength (right + left grip), speed (5 m, 20 m sprints), acceleration (10 to 20 m), agility (figure-of-eight run), explosive strength (vertical jump) and endurance (yo-yo intermittent shuttle run, 13-16 years only) were measured. Hierarchical multiple regression was used. The interaction of SAsr with body size (height and height x weight interaction) explained most of the variance in strength in both age groups, 9-12 years (51.6%) and 13-16 years (56.7%), and in speed (31.4%, 38.7%), acceleration (39.6%), and explosive strength (32.6%) among players 13-16 years. In contrast, SAsr alone explained limited amounts of variance in strength, speed, acceleration and vertical jump among players 9-12 years (1.4-4.5%) and 13-16 years (0-0.5%). Results for agility varied with CA group, while SAsr per se was the primary contributor to endurance among players 13-16 years (18.5% of the variance). Although the influence of body size and skeletal maturity status on performances was significant, the explained variance differed among tasks and between CA groups, and suggested a role for other factors affecting performances of the soccer players.

Perfis de envolvimento parental no futebol juvenil: Um estudo com jovens atletas / Perfiles de participación de los padres en el fútbol juvenil: Un estudio con atletas jóvenes / Parental involvement profiles in football: A study with young players

Este estudo analisou as diferenças na perceção dos atletas acerca dos comportamentos parentais, considerando também a importância do escalão desportivo dos atletas. Além disso, foi analisado se diferentes perfis de envolvimento parental, segundo a avaliação dos atletas aos seus pais, correspondiam a diferenças na orientação motivacional e na perceção de rendimento dos jovens atletas. Participaram no estudo 292 atletas do sexo masculino com idades compreendidas entre os 12 e 19 anos (M = 15.0; DP = 1.5), praticantes de futebol no campeonato nacional. Foram aplicados três instrumentos, (1) Questionário de Comportamentos Parentais no Desporto; (2) Escala de Objetivos de Realização no Desporto Juvenil; (3) Questionário de Perceção de Rendimento Desportivo. Os resultados indicaram (a) diferenças na perceção de comportamentos do pai e da mãe separadamente, sendo que, a perceção dos atletas variou em função do seu escalão desportivo; e (b) a orientação motivacional e a perceção de rendimento variaram em função do perfil de envolvimento parental percebido. Em suma, os resultados demonstram a importância do envolvimento parental no desporto juvenil, devendo este fator ser considerado pelos profissionais que intervêmjunto dos jovens atletas.(AU)

Este estudio analizó las diferencias en la percepción de los atletas sobre los comportamientos de sus padres, considerando también la importancia del nivel deportivo de los atletas. Además, se analizó si los diferentes perfiles de participación de los padres, según la evaluación de los deportistas sobre sus padres, se correspondían con diferencias en la orientación motivacional y en la percepción del rendimiento de los jóvenes deportistas. Participaron del estudio 292 atletas masculinos con edades entre 12 y 19 años (M = 15,0; SD = 1,5), futbolistas del campeonato nacional. Se aplicaron tres instrumentos, (1) Cuestionario de Conductas Parentales en el Deporte; (2) Escala de Metas de Logro en Deportes Juveniles; (3) Cuestionario de Percepción del Rendimiento Deportivo. Los resultados indicaron: (a)diferencias en la percepción de los comportamientos del padre y de la madre por separado, y la percepción de los deportistas varió según su nivel deportivo; e (b)la orientación motivacional y la percepción de rendimiento varió según el perfil de participación parental percibida. En resumen, los resultados demuestran la importancia de la participación de los padres en el deporte juvenil, y este factor debe ser considerado por los profesionales que trabajan con jóvenes deportistas.(AU)

This study analysed the differences in athletes’ perception of parental behaviours, considering the importance of athletes’ age category. It was also verified if different parental involvement profiles, according to athletes’ evaluation of their parents’ behaviours, corresponded to differences in motivational orientation and in performance perception of the young athletes. The study included 292 male athletes, aged between 12 and 19 years old (M = 15.0; DP = 1.5), playing football in the national championship. Three instruments were used: (1) Parental Behaviours in Sports Questionnaire; (2) Achievement goal scale for youth sport; (3) Sport Performance Perception Questionnaire. The results indicated: (a)differences in the perception of father’s and mother’s behaviours, separately, and these differences changed according to athletes’ age category; and (b)motivational orientation and performance perception varied according to the perceived parental involvement profile. In sum, the results demonstrate the importance of parental behaviours in youth sports and this aspect should be considered by professionals who work with young athletes.(AU)

Multidimensional and Longitudinal Approaches in Talent Identification and Development in Racket Sports: A Systematic Review.

BACKGROUND: Better methods to support talent identification and development processes may contribute to more effective and efficient athlete development programs in racket sports. Both researchers and practitioners recommend multidimensional and longitudinal approaches to better understand the nature of talent (development). However, the added value of these 'innovative' approaches has not yet been clarified for racket sports. This systematic review intends to gain further insight into the outcomes of multidimensional and longitudinal approaches for talent identification and development in racket sports and to provide directions for future talent research. METHODS: Electronic searches were conducted in PubMed, Scopus, SPORTDiscus, and Web of Science (January 2000-August 2022). Search terms covered the areas of racket sports and talent in sports. Studies using multidimensional and/or longitudinal talent approaches were included and analyzed regarding the methodology, included performance characteristics (i.e., anthropometrical, physiological, technical, tactical, psychological), and study findings. RESULTS: A total of thirty-two studies were included using multidimensional (n = 15), unidimensional longitudinal (n = 3) or multidimensional longitudinal designs (n = 14). Most research covered physiological characteristics (n = 28), while fewer articles investigated anthropometrics (n = 21) and technical characteristics (n = 16). Only limited research investigated psychological (n = 4) and tactical characteristics (n = 1). Almost all studies measured physiological characteristics in combination with other characteristics. There was moderate to strong evidence that physiological and technical characteristics have value for athlete development programs in racket sports. Positive but limited evidence was found for psychological and tactical characteristics. Anthropometrical assessments were generally used as controlling variables for maturation. Study designs varied, and many studies used unidimensional statistical models and analyses within multidimensional study designs and datasets. CONCLUSIONS: This review provides an overview of talent research using multidimensional and/or longitudinal approaches within racket sports and gives guidance on what characteristics to include in decision-making and monitoring processes. However, it remains difficult to draw conclusions about the added values of these approaches due to their variety in methodology. Future talent research should include more consistent study designs and conduct multidimensional and longitudinal studies using multivariate statistical approaches that benefit from the data's multidimensionality.

Changes in Sports Participation, Specialization, and Burnout From 7th to 12th Grade: Final Results From a 6-Year Longitudinal Study.

BACKGROUND: Previous studies show alarming rates of burnout and dropout from sports participation and physical activity in the youth population. Early sports specialization may increase the risk of injury, burnout, and eventual dropout from sports. HYPOTHESIS: Sports participation will decrease, specialization will increase, and burnout will increase from junior high to high school. STUDY DESIGN: Prospective longitudinal study. LEVEL OF EVIDENCE: Level 2b. METHODS: The graduating class of 2023 was surveyed longitudinally in the fall of each school year from 7th to 12th grade (n = 35-77 from middle to high school based on new enrollment participants and attrition). Survey questions asked about sports participation, specialization, and burnout. Responses were analyzed by grade level using mixed effects linear and logistic regression accounting for repeated measures. RESULTS: The number of days per week in which students engaged in at least 60 minutes of strenuous exercise progressively decreased from 7th through 12th grade from 4.0 to 2.3 days per week (P < 0.01). The percentage of students participating in sports also decreased from 7th to 12th grade from 82% to 39% (P < 0.01). More students stopped participating in a sport (38% vs 22% to 29%, P = 0.04), quit a sport to focus on a single sport (60% vs 46% to 49%, P = 0.01), or reported that 1 sport was most important to them (71% vs 54% to 67%, P = 0.06) in 9th grade. Burnout in sports did not differ significantly by grade level (19% to 23%, P > 0.99). In contrast, burnout in school was significantly more common in high school (54% to 69%) compared with middle school (36%, P < 0.01). Burnout in school was higher in female students compared with male students (68% vs 38%, P < 0.01). CONCLUSION: Organized sports participation and general physical activity decreased from middle to high school, with the entry into high school at 9th grade being a time at which a significant number of students dropped other sports to specialize in a single sport or stopped participating. Burnout in sports did not appear to increase with age; however, there was an increase in school-related burnout as students transitioned from middle to high school. CLINICAL RELEVANCE: Our results highlight the need for continued research into sports participation, specialization, and burnout in adolescents. In addition, health professionals and the community (parents, coaches, teachers) supporting youth athletes may consider positive interventions during the periods of transition from middle to high school to include facilitating different tracks of sports participation (including a developmental or recreational model of play) to reduce dropout from sport and supportive measures to lessen burnout from sports and from school.

Menstrual cycle characteristics, perceived impact on performance, and barriers to communication: Perspectives of high-performance adolescent athletes in Singapore.

The purpose of this study was to examine the menstrual cycle (MC) characteristics, explore the impact on performance, and identify barriers to and facilitators of MC-related communication among high-performance female adolescent athletes in Singapore. Ninety athletes (15.4 ± 1.8 years) from multiple sports completed an online questionnaire. Eighty-four athletes were postmenarcheal (menarcheal age 11.9 ± 1.3 years), including two who were using an oral contraceptive pill (OCP). Secondary amenorrhea, current or history of, was self-reported in 16% of athletes. Sixty-two percent and 67% of non-OCP athletes perceived that the MC affected their ability to train and compete, respectively. Athletes preferred speaking to a parent (85%) and a female figure (67%) about MC-related concerns. Through thematic analysis, three barriers to communication were constructed: (1) pervasive menstrual stigma, (2) constraints of the training environment, and (3) the low value placed on MC-related conversations. Two facilitators of communication were constructed: (1) respect athletes' individual experiences as menstruating girls and (2) foster a safe space for MC-related conversations. Findings demonstrated that menstrual irregularities are common in adolescent athletes and screening for MC disorders, particularly primary amenorrhea should be undertaken in this population, with clear support pathways for management including symptom mitigation. To support athletes in raising MC-related concerns when needed, structured communication pathways that consider individual preferences and involve a (female) point of contact should be established within the training environment. Improving menstrual health literacy among adolescent athletes before any misinformation or negative perceptions are firmly established may contribute to longevity in their athletic careers.

MRI segmentation of tooth tissue in age prediction of sub-adults - a new method for combining data from the 1st, 2nd, and 3rd molars.

PURPOSE: We aimed to establish a model combining MRI volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults and compare the age prediction performance of different combinations of all three molars, internally in the study cohort. MATERIAL AND METHOD: We examined 99 volunteers using a 1.5 T MR scanner with a customized high-resolution single T2 sequence. Segmentation was performed using SliceOmatic (Tomovision©). Age prediction was based on the tooth tissue ratio (high signal soft tissue + low signal soft tissue)/total. The model included three correlation parameters to account for statistical dependence between the molars. Age prediction performance of different combinations of teeth for the three molars was assessed using interquartile range (IQR). RESULTS: We included data from the 1st molars from 87 participants (F/M 59/28), 2nd molars from 93 (F/M 60/33) and 3rd molars from 67 (F/M 45/22). The age range was 14-24 years with a median age of 18 years. The model with the best age prediction performance (smallest IQR) was 46-47-18 (lower right 1st and 2nd and upper right 3rd molar) in males. The estimated correlation between the different molars was 0.620 (46 vs. 47), 0.430 (46 vs. 18), and 0.598 (47 vs. 18). IQR was the smallest in tooth combinations including a 3rd molar. CONCLUSION: We have established a model for combining tissue volume measurements from the 1st, 2nd and 3rd molars for age prediction in sub-adults. The prediction performance was mostly driven by the 3rd molars. All combinations involving the 3rd molar performed well.

Coach-athlete relationships and life skills development among Brazilian handball players: A prospective study / Relaciones entrenador-atleta y desarrollo de habilidades para la vida entre jugadores brasileños de balonmano: un estudio prospectivo

This study was to examine the prospective associations between coach-athlete relationship (CAR) and life skills development in youth handball players. This study employed a longitudinal research design. A total of 78 male handball players completed the Life Skills Scale for Sport and the Coach-Athlete Relationship Questionnaire over three waves of data collection: start of the season; midseason and end of the season. Data were analyzed using multivariate analysis of variance Pearson’s Correlation and Linear Multiple Regression (p<.05). The findings indicated the three dimensions of CAR seem to have higher effect on life skills subscales as the season progressed (i.e., higher effect on life skills at T3 compared to T2 and T1). Commitment and Complementarity were positively associated with several life skills subscales at all three timepoints. Results suggest that the quality of the CAR is an important determinant for the de-velopment of life skills in youth handball players across the sports season. (AU)

Este estudio tuvo como objetivo examinar las posibles asociaciones entre la relación entrena-dor-atleta (CAR) y el desarrollo de habilidades para la vida en jugadores juveniles de balon-mano. Este estudio empleó un diseño de investigación longitudinal. Un total de 78 jugadores masculinos de balonmano completaron la Escala de Habilidades para la Vida Deportiva y la Es-cala de Entrenadores. Cuestionario sobre la relación con los atletas en tres oleadas de recopi-lación de datos: inicio de la temporada; mitad de temporada y final de temporada. Los datos se analizaron mediante análisis multivariado de varianza, correlación de Pearson y regresión lineal múltiple (p<0,05). Los hallazgos indicaron que las tres dimensiones de CAR parecen te-ner un mayor efecto en las subescalas de habilidades para la vida a medida que avanzaba la temporada (es decir, un mayor efecto sobre las habilidades para la vida en T3 en comparación con T2 y T1). El compromiso y la complementariedad se asociaron positivamente con varias subescalas de habilidades para la vida en los tres momentos. Los resultados sugieren que la ca-lidad del CAR es un determinante importante para el desarrollo de habilidades para la vida en jugadores juveniles de balonmano a lo largo de la temporada deportiva. (AU)

A machine learning approach for the classification of sports based on a coaches' perspective of environmental, individual and task requirements: A sports profile analysis.

Well-designed talent programmes in sports with a focus on talent identification, orientation, development, and transfer support the engagement of young individuals and the pursuit of elite performance. To facilitate these processes, an analysis of task, environmental and individual characteristics per sport is much needed. The aims of this study were to 1) analyse whether unique profiles per sport could be established by generic characteristics and 2) to discuss similarities and differences for the potential application in talent development and transfer. By means of a validated survey, 1247 coaches from 34 sports ranked 18 characteristics on importance to their sports (0 = not important - 10 = very important). To discriminate the responses per sport a Discriminant Analysis (DA) was carried out. To refine the DA-classification, Uniform Manifold Approximation and Projection (UMAP) with CatBoost classifier was performed. To test the performance of the CatBoost classifier-algorithm, a confusion-matrix was generated. The cross-validated DA showed that 70.2% of the coaches were correctly classified to their sport. The UMAP/CatBoost technique revealed 75.1% accuracy with correctly predicted responses per sport ranging from 18.2% (sailing) to 98.2% (soccer). With varying precision, the algorithm was able to differentiate sports by importance of its characteristics indicating similarities and differences per sport.

Adult Negative Spectator Behavior at Youth Sporting Events.

Due to its competitive nature, youth sports may provide an environment that invites the display of negative parenting behavior and exposes children to adults outside of their own household. This study aimed to quantify the frequency of negative parent and spectator behavior at youth sporting events and compare incidences across different sports and age ranges. Investigators attended baseball, basketball, soccer, and football events in Central O'ahu, Hawai'i for children ages 6 to 10 years. Recorded spectator behaviors included alcohol use, smoking, swearing, and negative language (such as threats and violent language). Negative behaviors were reported at a majority (68%) of events. The 95% confidence intervals of the means (95% CIM) for all negative behaviors observed were overlapping, and we were not able to demonstrate statistically significant differences between the 4 sports. The lack of significance between sports may be due to the younger-player-age group, small sample size, and time of events.

Remodeling of Lumbar Spinal Osteoid Osteoma Resected With Microscopic Surgery in a 15-Year-Old Basketball Player: A Case Report.

This case report focuses on a 15-year-old competitive-level high school basketball player who experienced chronic low back pain. Diagnostic imaging revealed osteoid osteoma in the L5 posterior element, causing osteosclerotic deformity of the left lamina and more inferior facet. To return him to the condition of sports activity, less invasive surgery of microscopic tumor resection with autologous bone grafting was planned instead of CT-guided ablation, which can cause thermal injury to nearby tissues. This procedure could preserve spinal structures, including the facet, pedicle, and paravertebral muscles. The day after surgery, the patient experienced a complete resolution of lower back pain. He gradually resumed light exercise two months postoperatively. Three-month follow-up CT imaging revealed bone remodeling at the resection site, to return to complete basketball activities. Over five years, no tumor recurrence or symptoms were observed, and he maintained his competitive activity level.

Maturity Offset, Anthropometric Characteristics and Vertical Force-Velocity Profile in Youth Basketball Players.

This work aimed to analyze the relationships between maturity offset, anthropometric variables and the vertical force-velocity profile in youth (12-18 years old) male basketball players. The vertical force-velocity profile was measured in 49 basketball players, grouped in competitive-age categories, i.e., under 14, 16 and 18 years of age (U-14, U-16 and U-18, respectively). A bivariate correlational analysis was carried out between maturity offset, anthropometric variables (height, body mass, % fat, muscle mass, bone mass and body mass index (BMI)) and vertical force-velocity profile (theoretical maximal force [F0], theoretical maximal velocity [V0], theoretical maximal power [Pmax], force-velocity imbalance [Fvimb] and force-velocity profile orientation). The results showed significant correlations (p < 0.05) between Fvimb and maturity offset at early ages of training (12-15 years). The anthropometric profile was correlated (p < 0.05) with F0 in U-14, V0 in U-16, and Pmax in U-18 basketball players. The current findings suggest a relationship between the vertical force-velocity imbalance and maturity offset and the main vertical force-velocity profile variables. The vertical force-velocity profile is hypothesized as a useful index to correct vertical force-velocity deficits according to the maturity offset of male basketball players.

Virtual Workshops as an Effective and Engaging Policy Implementation Strategy: Lessons From the National Youth Sports Strategy.

BACKGROUND.: Implementation is an important piece of effective policymaking, but connecting local organizations with federal policy can be challenging. A virtual workshop structure can help engage implementation partners, especially when in-person events are not possible. The workshops described here leveraged virtual outreach and facilitation methods to foster community engagement, forge connections, and build relationships at the regional, state, and local levels. METHODS.: This article focuses on five virtual workshops. The planning phase consisted of selecting the geographic scope of each workshop, developing outreach and facilitation materials, and supporting event logistics. The execution and summary phase included tailoring materials, hosting the events, and producing follow-up materials. Networking, resource sharing, collaboration, and active facilitation were employed to promote engagement. RESULTS.: Registration for the virtual workshops included 223 individuals representing organizations in 28 states. Participants shared 133 resources. In a post-event evaluation, 93% of respondents indicated they could identify at least one new resource to support their efforts to increase youth sports participation in their community, and 94% indicated they plan to follow up and explore potential partnerships/collaborations with others they met or heard from at the workshop. Networking and resource sharing were identified as the most useful aspects of the workshops. CONCLUSIONS.: With careful planning and collaboration, virtual workshops represent a useful community engagement mechanism to bring policy into practice. Creating events focused on the participant experience supports health promotion professionals, engages communities, and takes a policy off the page and out to the people.

The effects of backward vs. forward running training on measures of physical fitness in young female handball players.

Introduction: This study examined the effects of an 8-week backward running (BR) vs. forward running (FR) training programmes on measures of physical fitness in young female handball players. Methods: Twenty-nine players participated in this study. Participants were randomly assigned to a FR training group, BR training group, and a control group. Results and discussion: Within-group analysis indicated significant, small-to-large improvements in all performance tests (effect size [g] = 0.36 to 1.80), except 5-m forward sprint-time in the BR group and 5- and 10-m forward sprint-time in the FR group. However, the CG significantly decreased forward sprint performance over 10-m and 20-m (g = 0.28 to 0.50) with no changes in the other fitness parameters. No significant differences in the amount of change scores between the BR and FR groups were noted. Both training interventions have led to similar improvements in measures of muscle power, change of direction (CoD) speed, sprint speed either forward or backward, and repeated sprint ability (RSA) in young female handball players, though BR training may have a small advantage over FR training for 10-m forward sprint time and CoD speed, while FR training may provide small improvements over BR training for RSAbest. Practitioners are advised to consider either FR or BR training to improve various measures of physical fitness in young female handball players.