Exploring the existence, strength, and independence of relative age and maturation selection biases: a case study in Gaelic football talent development programmes.

BACKGROUND: Biological maturity and relative age player selection biases are well documented in youth sports. However, there has been limited examination of the relationship between these biases. AIM: This study investigated the presence, strength, and independence of relative age and biological maturity selection biases in Gaelic football. SUBJECTS AND METHODS: A total of 247 male players from U14 to U16, from two talent academies were assessed for relative age (decimal age (DA)) and biological maturity (discrepancy between biological and chronological age (BA-CA)). RESULTS: Relative age effects (RAE) were observed in the U14 (DA = 0.62, d = 0.40) and U15 squads (DA = 0.57. d = 0.26) only. A bias towards advanced maturity status was present at U14 (BA-CA = 0.60, d = 0.83), U15 (BA-CA = 0.78, d = 0.89), and U16 (BA-CA, d = 1.01). There was a trivial (U14, r(83) = -0.210; U15, r(88) = 0.060) and low (U16, r(76) = 0.352) correlation between relative age and maturity status. CONCLUSION: Substantial maturity selection biases and, to a lesser degree, relative age biases are evident in youth Gaelic football. Critically, these biases are independent constructs. Coaches and policy makers should be educated on the distinct influences of relative age and maturation, and on strategies to address these biases.

Retrospective survey of youth sports participation: Development and assessment of reliability using school records.

Many youths participate in sports, and it is of interest to understand the impact of youth sports participation on later-life outcomes. However, prospective studies take a long time to complete and retrospective studies may be more practical and time-efficient to address some questions. We pilot a retrospective survey of youth sports participation and examine agreement between respondent's self-reported participation with high school records in a sample of 84 adults who graduated from high school between 1948 and 2018. The percent agreement between our survey and the school resources for individual sports ranged between 91.5% and 100%. These findings provide preliminary evidence for the reliability of retrospective self-report of youth sports participation. This survey may serve as an efficient approach for evaluating relationships between involvement in youth sports and health outcomes later in adulthood.

Adolescents' healthy sports behavior model based on the theory of social-ecological system / Modelo de comportamento esportivo saudável de adolescentes baseado na teoria do sistema socioecológico / Modelo de comportamiento deportivo saludable de adolescentes basado en la teoría del sistema socioecológico

ABSTRACT Introduction: Education administrative departments and schools should regard sports as an integral part of school education and allow students to use sports every day. Guarantee the time for sports activities; schools should organize various forms of extracurricular sports activities". Objective: Based on the ecological system theory, the paper constructs a three-factor structural model that restricts youth sports participation and compiles a scale of factors restricting youth sports participation. Methods: The thesis selected 1,800 primary and secondary school students as the research object and used exploratory factor analysis to explore the questionnaire structure on the obstacles to sports participation. Results: 1) Exploratory factor analysis, the cumulative contribution rate of the first three factors extracted was 58.90%, and the load of each factor was more significant than 0.4. The three factors were school factors, family factors, and personal factors in order; 2) Reselected subjects, Exploring the three-factor structural model of obstacles to sports participation were verified. The final modified model RMSEA was 0.071, CFI was 0.98, and χ2/df was 8.55. The three factors were school factors, family factors, and personal factors. Conclusions: The fit of the three-factor structural indicators restricting youth sports participation is ideal, and the model is relatively stable. The "Questionnaire on Restricting Factors of Youth Sports Participation" can be used as a measurement tool to evaluate and understand youth sports participation constraints. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução: Departamentos administrativos de educação e escolas devem considerar os esportes como parte integrante da educação escolar e permitir que os alunos pratiquem esportes todos os dias. Garantia de tempo para atividades esportivas; as escolas devem organizar várias formas de atividades esportivas extracurriculares. Objetivo: Com base na teoria do sistema ecológico, o artigo constrói um modelo estrutural de três fatores que restringe a participação em esportes de jovens e compila uma escala de fatores que restringem a participação em esportes de jovens. Métodos: a tese selecionou 1.800 alunos do ensino fundamental e médio como objeto de pesquisa e utilizou uma análise fatorial exploratória para explorar a estrutura do questionário sobre obstáculos à participação esportiva. Resultados: 1) Análise fatorial exploratória, a taxa de contribuição cumulativa dos três primeiros fatores extraídos foi de 58,90% e a carga de cada fator foi mais significativa do que 0,4. Os três fatores eram fatores escolares, fatores familiares e fatores pessoais em ordem; 2) Foram verificados os temas reelecionados, explorando o modelo estrutural de três fatores de obstáculos à participação esportiva. O modelo RMSEA modificado final foi 0,071, CFI foi 0,98 e χ2 / df foi 8,55. Os três fatores eram fatores escolares, fatores familiares e fatores pessoais. Conclusões: O ajuste dos indicadores estruturais de três fatores que restringem a participação dos jovens em esportes é ideal e o modelo é relativamente estável. O "Questionário sobre Fatores Restritivos da Participação em Esportes de Jovens" pode ser usado como uma ferramenta de medição para avaliar e compreender as limitações da participação em esportes de jovens. Nível de evidência II; Estudos terapêuticos: investigação dos resultados do tratamento.

RESUMEN Introducción: Los departamentos administrativos de educación y las escuelas deben considerar los deportes como una parte integral de la educación escolar y permitir que los estudiantes utilicen los deportes todos los días. Garantizar el tiempo para actividades deportivas; las escuelas deberían organizar diversas formas de actividades deportivas extracurriculares. Objetivo: Basado en la teoría del sistema ecológico, el artículo construye un modelo estructural de tres factores que restringe la participación deportiva juvenil y compila una escala de factores que restringen la participación deportiva juvenil. Métodos: La tesis seleccionó a 1.800 estudiantes de primaria y secundaria como objeto de investigación y utilizó un análisis factorial exploratorio para explorar la estructura del cuestionario sobre los obstáculos a la participación deportiva. Resultados: 1) Análisis factorial exploratorio, la tasa de contribución acumulada de los tres primeros factores extraídos fue de 58,90% y la carga de cada factor fue más significativa que 0,4. Los tres factores fueron factores escolares, factores familiares y factores personales en orden; 2) Se verificaron sujetos reselegidos, Explorando el modelo estructural de tres factores de obstáculos a la participación deportiva. El modelo final modificado RMSEA fue 0.071, CFI fue 0.98 y χ2 / df fue 8.55. Los tres factores fueron factores escolares, factores familiares y factores personales. Conclusiones: El ajuste de los indicadores estructurales de tres factores que restringen la participación deportiva juvenil es ideal y el modelo es relativamente estable. El "Cuestionario sobre factores restrictivos de la participación deportiva juvenil" puede utilizarse como una herramienta de medición para evaluar y comprender las limitaciones de la participación deportiva juvenil. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados del tratamiento.

Understanding the impact of COVID-19 on youth sport in Australia and consequences for future participation and retention.

BACKGROUND: COVID-19 continues to represent the single biggest challenge to contemporary community sport globally. Compliance with social distancing policies, strict return-to-play protocols, and COVID-19 specific training has, perhaps, forever changed the way that children and young people engage in organised sport. Within this context, and while many children and families seek to re-engage with community sport, we (researchers and sport practitioners) have an obligation to ask questions about how the pandemic has impacted youth sport, understand the short- and long-term consequences, and explore what (if any) opportunities can be seized to assist and improve future participation and retention. The aim of this paper was to present an in-depth exploration of the impact of COVID-19 on youth sport in South Australia. METHODS: Within an interpretive descriptive methodology, this qualitative investigation draws on rich, individual interview and focus group data with 39 youth (ages 15-18), parents, coaches, and sport administrators. A reflexive thematic analysis was undertaken, leading to the development of four substantive themes. RESULTS: We conceptualised the '4 Rs' to advance theoretical understandings about the pandemic's impact on youth sport, including the themes 'recognising struggle', 'reconnection', 're-engaging after restrictions, and 'reimagining sport'. The themes captured insights about a decline in mental wellbeing and physical activity, an increase in family connectedness, the challenge for sports to attract volunteers and participants back into sport, and the opportunities to reset values and philosophies underpinning the provision of youth sport. CONCLUSION: The findings provide valuable insight into the youth sport setting as a result of the global pandemic and suggest that families, sporting clubs and sporting organisations require additional resources and tools (for example, support for parents to facilitate their children's training at home during lockdown) to aid recovery efforts and to ensure the survival and prosperity of youth sport into the future.

Injuries in youth football and the relationship to player maturation: An analysis of time-loss injuries during four seasons in an English elite male football academy.

A better insight into injuries in elite-youth football may inform prevention strategies. The purpose of this prospective cohort study was to investigate the frequency, incidence, and pattern of time-loss injuries in an elite male football academy, exploring injuries in relation to age and maturation status. Across four consecutive playing seasons, playing exposure and injuries to all academy players (U'9 to U'21) were recorded by club medical staff. Maturation status at the time of injury was also calculated for players competing in U'13 to U'16 aged squads. Time-loss injury occurrence and maturation status at time of injury were the main outcome measures. A total of 603 time-loss injuries were recorded, from 190 different players. Playing exposure was 229 317 hours resulting in an overall injury rate of 2.4 p/1000 h, ranging from 0.7 p/1000 h (U'11) to 4.8 p/1000 h (U'21). Most injuries were traumatic in mechanism (73%). The most common injury location was the thigh (23%), and the most common injury type was muscle injury (29%) combining to provide the most common injury diagnosis; thigh muscle injury (17%). In U'13-U'16 players, a higher number of injuries to early-maturing players were observed in U'13-U'14 players, while more injuries to U'15-U'16 players occurred when classed as "on-time" in maturity status. Maturation status did not statistically relate to injury pattern; however, knee bone (not-fracture) injuries peaked in U'13 players while hip/groin muscle injuries peaked in U'15 players.

Injury patterns differ with age in male youth football: a four-season prospective study of 1111 time-loss injuries in an elite national academy.

OBJECTIVES: To describe age group patterns for injury incidence, severity and burden in elite male youth football. METHODS: Prospective cohort study capturing data on individual exposure and time-loss injuries from training and matches over four seasons (2016/2017 through 2019/2020) at a national football academy (U13-U18; age range: 11-18 years). Injury incidence was calculated as the number of injuries per 1000 hours, injury severity as the median number of days lost and injury burden as the number of days lost per 1000 hours. RESULTS: We included 301 players (591 player-seasons) and recorded 1111 time-loss injuries. Overall incidence was 12.0 per 1000 hours (95% CI 11.3 to 12.7) and burden was 255 days lost per 1000 hours (252 to 259). The mean incidence for overall injuries was higher in the older age groups (7.8 to 18.6 injuries per 1000 hours), while the greatest burden was observed in the U16 age group (425 days; 415 to 435). In older age groups, incidence and burden were higher for muscle injuries and lower for physis injuries. Incidence of joint sprains and bone stress injuries was greatest for players in the U16, U17 and U18 age groups, with the largest burden observed for U16 players. No clear age group trend was observed for fractures. CONCLUSION: Injury patterns differed with age; tailoring prevention programmes may be possible.

Family Affluence Relationship to Sports Specialization in Youth Athletes.

Our objective was to examine the association between participant-reported family affluence and sport specialization level. We conducted a cross-sectional investigation of adolescent athletes. Specifically, participants completed a level of sport specialization (low/moderate/high) questionnaire and the Family Affluence Scale. The majority (52%) of the 195 youth athlete participants reported low, 33% reported moderate, and 15% reported high sport specialization. Sport specialization groups were similar in age (mean = 15.3 ± 1.6 years), proportion of females (49%), and time spent training (mean = 11.9 ± 5.0 hours per week). The high sport specialization group reported significantly greater family affluence than the low sport specialization group (Family Affluence Scale = 10.4 ± 1.7 vs 9.2 ± 1.9; P = .005). After covariate adjustment, higher levels of sport specialization remained significantly associated with greater family affluence (ß = 0.48, 95% confidence interval = 0.11-0.86). Understanding the relationship between family affluence and sports specialization affords an opportunity to better identify and monitor populations likely to specialize in a single sport during high school.

Longitudinal Association Between Participation in Organized Sport and Psychosocial Development in Early Childhood.

OBJECTIVE: To explore whether the associations between developmental delays in the first year of life and psychosocial outcomes in preschool children are affected by participation in organized sport. STUDY DESIGN: Data were obtained from the infant cohort of the Growing Up in Ireland project. Parents reported on child development (Ages and Stages Questionnaire) at age 1 year, psychosocial characteristics (Strengths and Difficulties Questionnaire) at ages 3 and 5 years, and engagement in organized sport at age 5 years. Data were analyzed using mixed models. RESULTS: At age 1 year, 15% of the cohort was classified as having developmental delays. These children exhibited more behavioral difficulties (0.55, ±0.27; mean difference, ±95% confidence limits [CL]) (P < .0001) and fewer prosocial behaviors (-0.54, ±0.11) (P < .0001) at age 3 years. For boys in this group, engagement in sport was associated with a significant decrease in behavioral difficulties between ages 3 and 5 years (-0.44, ±0.39) (P = .03). Compared with those classified as lacking regular engagement (ie, never engaging, or engaging <1 hour/week), the relative effect of sport on changes in behavioral difficulties for boys with developmental delays was statistically significant (0.70, ±0.59) (P = .02). Participation in sport was not associated with significant changes in behavioral difficulties for girls, or a significant change in prosocial behaviors for boys or girls. CONCLUSIONS: Regular participation in sport by boys could attenuate some of the behavioral difficulties associated with early development. Lack of opportunities for engaging in sport could negatively affect boys' behavioral regulation in the preschool period.

Mechanisms explaining the birthplace effect for male elite football players.

Earlier research shows that wide regional variations exist in the success of athletes' talent development but is divided with respect to the role of urbanity: both low and high urbanity have been identified as settings that contribute to the presence of talent hotspots. In this article, we intend to provide more insight into the role of urbanity in talent development in Dutch football. We used public data on the regional background of male elite players (N = 825) and combined this with public data on municipal characteristics from Statistics Netherlands and other sources: urbanity, football participation, instructional resources and population composition effects (migration background and income of inhabitants). Linear regression analysis showed that football participation, the proportion of non-western migrants and median income predict "talent yield", i.e., the proportion of young people that reach an elite level in a municipality. Urbanity does not have an independent influence when the proportion of non-western migrants in the municipality is taken into account. The presence of instructional resources does not have an independent influence. The results suggest that characteristics of the built environment, such as indoor and outdoor play opportunities, may be less influential in talent development than previously assumed.

The influence of initial selection age, relative age effect and country long-term performance on the re-selection process in European basketball youth national teams.

The aims of the study were to: (a) analyse the re-selection patterns in European youth basketball national teams, and (b) investigate how the chance of re-selection is influenced by the initial selection age and relative age of the players, as well as the long-term performance of the country at the youth level. The sample consisted of 8362 basketball players (5038 men, 3324 women) born 1988-1997 who have participated in at least one U16, U18 or U20 European youth basketball championship between 2004 and 2017. The results from the survival analysis showed that around 75% of male and 80% of female players participating in a championship were re-selected the following year. Also, initial selection age, relative age effect, and the country long-term performance influenced the re-selection rates, with relationships being different between men and women. To conclude, the results of the present study show that the re-selection process by which players progress in European youth national basketball teams is complex and influenced by several different factors.

Injury incidence and burden in a youth elite football academy: a four-season prospective study of 551 players aged from under 9 to under 19 years.

OBJECTIVE: Investigate the incidence and burden of injuries by age group in youth football (soccer) academy players during four consecutive seasons. METHODS: All injuries that caused time-loss or required medical attention (as per consensus definitions) were prospectively recorded in 551 youth football players from under 9 years to under 19 years. Injury incidence (II) and burden (IB) were calculated as number of injuries per squad season (s-s), as well as for type, location and age groups. RESULTS: A total of 2204 injuries were recorded. 40% (n=882) required medical attention and 60% (n=1322) caused time-loss. The total time-loss was 25 034 days. A squad of 25 players sustained an average of 30 time-loss injuries (TLI) per s-s with an IB of 574 days lost per s-s. Compared with the other age groups, U-16 players had the highest TLI incidence per s-s (95% CI lower-upper): II= 59 (52 to 67); IB=992 days; (963 to 1022) and U-18 players had the greatest burden per s-s: II= 42.1 (36.1 to 49.1); IB= 1408 days (1373 to 1444). Across the cohort of players, contusions (II=7.7/s-s), sprains (II=4.9/s-s) and growth-related injuries (II=4.3/s-s) were the most common TLI. Meniscus/cartilage injuries had the greatest injury severity (95% CI lower-upper): II= 0.4 (0.3 to 0.7), IB= 73 days (22 to 181). The burden (95% CI lower-upper) of physeal fractures (II= 0.8; 0.6 to 1.2; IB= 58 days; 33 to 78) was double than non-physeal fractures. SUMMARY: At this youth football academy, each squad of 25 players averaged 30 injuries per season which resulted in 574 days lost. The highest incidence of TLI occurred in under-16 players, while the highest IB occurred in under-18 players.

How parental socioeconomic status contribute to children's sports participation in China: A cross-sectional study.

Socioeconomic status (SES) is an important factor contributing to health inequality. This study aimed to investigate factors that predict junior school students' sports participation, identify the mechanisms underlying transmission of social resources and assess the mediating effects of classmate support and parental involvement on the relationship between parental SES and children's sports participation. 4829 males and 4536 females (mean age = 13.56 years, standard deviation = 0.686 years) participated in the study. Multivariate regression was adopted to analyze the determinants of junior school students' sports participation and multiple mediation analyses were used to analyze the hypothesized model. The results indicated that parental SES is significantly and directly correlated with junior school students' sports participation. In addition, parental SES has a significant indirect effect on sports participation through classmate support and parental involvement. Furthermore, the mediation effect of classmate support on the association between parental SES and sports participation is stronger than that of parental involvement. To promote and facilitate the participation of junior school students', strategies should be developed by government and social workers to strengthen classmate support and parental involvement.

The UEFA Heading Study: Heading incidence in children's and youth' football (soccer) in eight European countries.

To assess the real-life magnitude of the heading incidence in children's and youth' football in eight European countries with different "football cultures," a cross-sectional observational design, in which one match per team in 480 different teams from eight European countries (2017/18-2018/19), was recorded by video. One training session was recorded in 312 teams. Clubs with Under-10, Under-12 (female/male/mixed), and Under-16 female and male teams were eligible to participate. Heading frequencies and types were analyzed. Results are presented as headers per match/training and per team. Incidence rates (IR) per 1000 match/training hours were calculated. Under-10 teams carried out the lowest average number of headers per match (8.8), followed by Under-16 female (17.7), Under-12 (18.4), and Under-16 male (35.5). Total number of headers per match and team varied between countries. 80% of the total number of headers were single intentional headers, 12% heading duels, 3% unintentional headers by getting hit, and 5% others (trends apparent in all age groups). Three head injuries occurred during match play corresponding to an IR of 0.70 (95% CI, 0.23-2.16). The lowest number of headers per training and team was found in Under-10 (21.3), followed by Under-16 females (34.1), Under-12 (35.8), and Under-16 males (45.0). In conclusion, this large-scale study presents novel data about the number and type of headers in youth' football throughout Europe. A more precise understanding of the heading incidence, specifically in young players, is mandatory for the debate of restrictions on heading in youth football.

The association between adolescent football participation and early adulthood depression.

Concerned about potentially increased risk of neurodegenerative disease, several health professionals and policy makers have proposed limiting or banning youth participation in American-style tackle football. Given the large affected population (over 1 million boys play high school football annually), careful estimation of the long-term health effects of playing football is necessary for developing effective public health policy. Unfortunately, existing attempts to estimate these effects tend not to generalize to current participants because they either studied a much older cohort or, more seriously, failed to account for potential confounding. We leverage data from a nationally representative cohort of American men who were in grades 7-12 in the 1994-95 school year to estimate the effect of playing football in adolescent on depression in early adulthood. We control for several potential confounders related to subjects' health, behavior, educational experience, family background, and family health history through matching and regression adjustment. We found no evidence of even a small harmful effect of football participation on scores on a version of the Center for Epidemiological Studies Depression scale (CES-D) nor did we find evidence of adverse associations with several secondary outcomes including anxiety disorder diagnosis or alcohol dependence in early adulthood. For men who were in grades 7-12 in the 1994-95 school year, participating or intending to participate in school football does not appear to be a major risk factor for early adulthood depression.

Evaluation of adolescent sport specialization and injury mechanism by sex: A secondary analysis.

OBJECTIVES: The purpose of this study was to compare the association of sport specialization with previous overuse and acute injuries between male and female adolescent athletes. DESIGN: Cross-sectional study. METHODS: Questionnaires were completed by adolescent athletes from various sports at sport club summer events in the state of Wisconsin. Adolescent athletes (12-18 years old) who were active in organized sports in the previous year were recruited. The questionnaire contained demographics, sport participation, sport specialization classification, and previous injury history. Sport specialization classification was determined using common methods in sport specialization research. Previous injury was restricted to athletic injuries that occurred in the past year. RESULTS: Two-thousand and eleven participants (age=13.7±1.6 years, females=989) completed the questionnaire. Highly specialized athletes were more likely to report both acute and overuse injuries compared to low specialization athletes. However, this relationship differed by sex, with only moderate and highly specialized females being more likely (Moderate: OR [95%CI]=1.74 [1.18-2.58], p=0.005; High: OR [95%CI]=1.69 [1.14-2.53], p=0.010) to report an overuse injury compared to low specialization females. Highly specialized female athletes were more likely to report an acute injury (High: OR [95%CI]=1.46 [1.06-2.02], p=0.022) compared to low specialization females. Highly specialized male athletes were not associated with overuse or acute injuries. CONCLUSIONS: Highly specialized athletes were more likely to report acute and overuse injuries. However, when this analysis was separated by sex, only highly specialized females were more likely to report a previous overuse or acute injury.

Parental awareness and engagement in the Active Kids program across socioeconomic groups.

OBJECTIVES: In 2018, the New South Wales (NSW) Government implemented a State-wide program to reduce the cost barrier to organised sport and physical activity participation. We explored parent/carer's awareness and children's engagement in the Active Kids program across socioeconomic groups and used the NSW Population Health Survey (PHS) to validate engagement in the program. DESIGN: Cross-sectional. METHODS: Data were obtained from the 2018 NSW PHS and the Active Kids program registration database. We compared demographic characteristics of children who had registered for the program in the registration database with children in the weighted NSW PHS. Multinomial regression models were used to determine whether socioeconomic status was associated with parent/carer awareness and children's engagement in the program. RESULTS: Parent/carer's in the most disadvantaged quartile were twice as likely to have never heard of the Active Kids program (OR: 2.04, 95% CIs 1.31, 3.16) or to have heard or the program but not registered (OR: 1.94, 95% CIs 1.26, 3.00), and more than twice as likely to have registered for a voucher, but not followed through and redeemed the voucher (OR: 2.68, 95% CIs 1.27, 5.63) compared with the least disadvantaged quartile. CONCLUSIONS: The Active Kids program has provided financial support for organised sport and physical activity to a large number of children. However, there are still a substantial proportion of socially disadvantaged groups who are unaware or have not engaged in the program. Further targeted work is required to increase the awareness and engagement in the program for socially disadvantaged groups.

The role of growth and maturation during adolescence on team-selection and short-term sports participation.

BACKGROUND: During adolescence, deselection from sport occurs during team try-outs when month of birth, stage of growth and maturation may influence selection. AIM: The purpose of this study was to identify differences in growth and maturity related factors between those selected and deselected in youth sports teams and identify short-term associations with continued participation. SUBJECTS AND METHODS: Eight hundred and seventy participants, aged 11-17 years, were recruited from six sports try-outs in Saskatchewan, Canada: baseball, basketball, football, hockey, soccer and volleyball. Two hundred and forty-four of the initial 870 (28%) returned for follow-up at 36 months. Chronological (years from birth), biological (years from age at peak height velocity (APHV)) and relative (month of birth as it relates to the selection band) ages were calculated from measures of date of birth, date of test, height, sitting height and weight. Parental heights were measured or recalled and participant's adult height predicted. Reference standards were used to calculate z-scores. Sports participation was self-reported at try-outs and at 36-month follow-up. RESULTS: There was an over-representation of players across all sports born in the first and second quartiles of the selection bands (p < 0.05), whether they were selected or deselected. z-scores for predicted adult height ranged from 0.1 (1.1) to 1.8 (1.2) and were significantly different between sports (p < 0.05). Height and APHV differences (p < 0.05) were found between selected and deselected male participants. In females only weight differed between selected and deselected female hockey players (p < 0.05); no further differences were found between selected and deselected female participants. Four per cent of deselected athletes exited sports participation and 68% of deselected athletes remained in the same sport at 36 months, compared with 84% of selected athletes who remained in the same sport. CONCLUSIONS: It was found that youth who attended sports team's try-outs were more likely to be born early in the selection year, be tall for their age, and in some sports early maturers. The majority of both the selected and deselected participants continued to participate in sport 36 months after try-outs, with the majority continuing to participate in their try-out sport.

The participation in organised sport doubles the odds of meeting physical activity recommendations in 7-12-year-old children.

The purpose of this study was to determine the contributing role of organised sport participation to daily physical activity (PA) and to describe the PA during training. Children aged 7-12 wore the accelerometer for 1 week. Children with activity data for a minimum of 5 days were included in the analysis (n = 492). Evenson cut-points were used to extract PA data for whole day and training sessions. Compliance with PA recommendations was assessed with two methods - weekly average and daily data. More than half (52.5%) of the children participated in an organised sport at least once a week. Participation in organised sport three or more times a week increased the odds of meeting PA recommendations (average method: OR = 4.02, 95% CI: 1.98-8.19, p < 0.001, days method: OR = 2.82, 95% CI: 1.35-5.88, p = 0.006). On average, children acquired 23.3 ± 15.3 min of moderate to vigorous PA (MVPA) during trainings, while boys accrued more MVPA minutes compared to girls (ß = 5.2, 95% CI: 2.4-8.0) and the training time MVPA decreased with age (ß = -1.0, 95% CI: -1.9 to -0.1), respectively. Each additional MVPA minute during training increased daily MVPA by 1.3 min (95% CI: 1.1-1.5). On days with training children accumulated 24.9 (95% CI: 21.8-28.0) more MVPA minutes compared to days without training. In conclusion, these findings highlight the importance of organised sport in supporting the PA levels of children. However, participation in the organised sport only is not sufficient to meet PA recommendations, and therefore, PA should be supported throughout the day.

Parents' Awareness and Perceptions of Sport Specialization and Injury Prevention Recommendations.

OBJECTIVE: To conduct a survey of parents to determine their knowledge of sport volume recommendations and examine their perceptions toward sport specialization. DESIGN: Cross-sectional survey. SETTING: Youth sport athletic tournaments, competitions, and practices. PATIENTS OR OTHER PARTICIPANTS: Parents (n = 1000, 614 women, age: 44.5 ± 6.7 years) of youth athletes completed the survey. Parents had to have a child between 10 and 18 years of age who participated in organized sport in the previous 12 months. INTERVENTIONS: The survey was anonymous and consisted of yes/no and Likert-scale questions and consisted of background of parent and child and perceptions and knowledge of safe sport recommendations. An expert panel validated the survey. MAIN OUTCOME MEASURES: Data were summarized by frequencies, proportions (%), and mean values and SDs, when appropriate. Chi-square analyses were used to determine if parent sex influenced distributions. RESULTS: Over 80% of parents had no knowledge of sport volume recommendations regarding h/wk (84.5%), mo/yr (82.2%), or simultaneous participation in multiple leagues (89.9%). Twenty-four percent of parents considered it appropriate to participate in multiple leagues in the same sport, whereas 60.5% considered it appropriate to participate in multiple leagues of a different sport. Thirty-four percent of parents indicated that they were concerned about the risk of injury in youth sports. Although 55% of parents considered sport specialization a problem in youth sports, only 43.3% thought that year-round sport participation increased the chances of sustaining an overuse injury. Female parents were more likely to be concerned about injury and believe that year-round sport participation results in overuse injury compared with men. CONCLUSIONS: Recommendations associated with youth sport participation are not well known. However, parents are concerned about the risk of injury and consider sport specialization a problem.

The environment contribution to gender differences in childhood obesity and organized sports engagement.

OBJECTIVE: This study aims to analyze gender-specific associations between sports activity outside of school and obesity, observing to what extent the local built environment contributes to the patterns found. METHODS: A total of 2253 children aged 6.0-11.0 years were assessed: 49.3% girls and 50.7% boys. Children's weight and height were measured, age and sex-specific BMI cut-off points were used to define normal vs overweight/obesity. Children's organized sports (OS) activity was assessed by questionnaire, and local facilities for children's engagement in OS were analyzed. Logistic regression models were computed, adjusted for confounding variables. RESULTS: Results showed greater overweight and obesity (25.1% vs 20.1%) and lower OS engagement (66.5% vs 73.8%) in girls as well as greater impact of OS engagement on weight status in girls (OR for having a normal weight = 1.434 in girls vs 1.043 in boys). Additionally, opportunities to engage in OS were scarce for girls. CONCLUSIONS: The gender gap in children's weight status and OS engagement might be enhanced by an environmental mismatch that undermines girls' opportunities to play sports. There should be more opportunities for girls to engage in their favorite sports as a means to tackle the obesity epidemic and to promote gender equality.