Sports Specialization and Sports-Related Injuries in Japanese School-Aged Children and Adolescents: A Retrospective Descriptive Study

Early sports specialization in Japanese young soccer players and related factors

Although understanding the status of sports participation is essential for preventing injuries in young athletes, the level of specialization and relevant information in Japan is unknown. This study aimed to clarify the status of sports specialization and examine the relationships between specialization and training status in Japanese young soccer players. Four hundred Japanese young male soccer players were included. The players' parents completed a web questionnaire that consisted of three-point questions regarding specialization and training status (year, days of playing soccer, age when starting soccer). The level of specialization and accompanying information were calculated, and data were compared by specialization status. Of the participants, 53.8% demonstrated a high level of specialization. In addition, 74.5% considered soccer more important than other sports, 89.0% trained in soccer for more than 8 months of the year, and 74.0% had quit other sports to focus on soccer or played only soccer. The proportion of participants who played only soccer was significantly higher in the high-specialization group (37.6%) than in the moderate-specialization (22.5%; P < .01) and low-specialization (7.1%; P < .01) groups. By specialization status at grades 4 to 6 (9-12 years), 40.3% of participants demonstrated a high level of specialization. Young Japanese soccer players tend toward early specialization. Factors contributing to the high specialization level are being active throughout the year and rarely playing other sports. Training volume should be controlled, and an environment allowing young soccer players to participate in other sports simultaneously is needed, with early specialization being avoided.

Injury Patterns in Highly Specialized Youth Athletes: A Comparison of 2 Pathways to Specialization

CONTEXT

Sport specialization, commonly defined as intensive year-round training in a single sport to the exclusion of other sports, has been associated with an increased risk for overuse injury. Two pathways to becoming highly specialized are recognized: (1) having only ever played 1 sport (exclusive highly specialized) and (2) quitting other sports to focus on a single sport (evolved highly specialized). Understanding the differences in injury patterns between these groups of highly specialized athletes will inform the development of injury-prevention strategies.

OBJECTIVE

To compare the distribution of injury types (acute, overuse, serious overuse) among evolved highly specialized athletes, exclusive highly specialized athletes, and low-moderately specialized athletes.

DESIGN

Cross-sectional study.

SETTING

Tertiary care pediatric sports medicine clinic between January 2015 and April 2019.

PATIENTS OR OTHER PARTICIPANTS

A total of 1171 patients (age = 12.01-17.83 years, 59.8% female) who played ≥1 organized sports, presented with a sport-related injury, and completed a sports participation survey.

MAIN OUTCOME MEASURE(S)

Distribution of injury types (acute, overuse, serious overuse).

RESULTS

The percentage of injuries due to overuse was similar between the exclusive and evolved highly specialized athletes (59.2% versus 53.9%; P = .28). Compared with low-moderately specialized athletes, exclusive and evolved highly specialized athletes had a higher percentage of overuse injuries (45.3% versus 59.2% and 53.9%, respectively; P = .001). Multivariate analysis of the highly specialized groups revealed sport type to be a significant predictor of a higher percentage of injuries due to overuse, with individual-sport athletes having increased odds of sustaining an overuse injury compared with team-sport athletes (odds ratio = 1.95; 95% CI = 1.17, 3.24).

CONCLUSIONS

The distribution of injury types was similar between evolved and exclusive highly specialized youth athletes, with both groups having a higher percentage of injuries due to overuse compared with low-moderately specialized athletes. Among highly specialized athletes, playing an individual sport was associated with a higher proportion of overuse injuries compared with playing a team sport.

Prevalence of and Factors Associated with Sports Injuries in 11,000 Japanese Collegiate Athletes

BACKGROUND

To establish the 1-year prevalence of sports injuries and explore associations of various factors with a sports injury in Japanese collegiate athletes.

METHODS

The data were collected through a web-based survey of Japanese collegiate athletes associated with UNIVAS (Japan Association for University Athletics and Sport). The survey questions asked about athletes' personal characteristics, sports participation, and injuries sustained within the previous year. Follow-up questions on the details regarding the three most serious injuries were asked. Differences in proportions of athlete characteristics between males and females and between injured and uninjured were explored with the chi-square test. Factors associated with sustaining an injury were determined with regression analysis.

RESULTS

The prevalence of injuries among Japanese collegiate athletes is high, and most of the sustained injuries require athletes to take a considerable time off training and competition indicating their severity. Athletes from year two and higher at the university, overweight or obese, training more often per week, and with longer sports experience were more likely to sustain an injury within the previous year.

CONCLUSIONS

There is compelling evidence to suggest that excessive training and insufficient recovery may be contributing to their increased risk of injury. These findings underscore the importance of implementing evidence-based training programs and recovery strategies to mitigate injury risk and optimize performance outcomes among this population.

Correlates of early attrition from school sports clubs in male senior high school students: a 2.4-year follow-up study

The correlation between early attrition and school sports clubs has been underexplored. This study aims to clarify the correlates of early attrition from school sports clubs at a private male senior high school in Fukuoka Prefecture, Japan. Of the 928 first-year students, 331 belonging to the school's sports clubs were included in this study. A baseline survey was conducted in May 2017 and a follow-up survey was conducted in October 2019. This study defined early attrition as a student who quit a sports club earlier than April in their third year. Examined correlates for early attrition consisted of biological, intrapersonal, interpersonal, and institutional factors. We used univariate logistic regression analysis, in which early attrition was the response variable and the examined correlates were the explanatory variables, and calculated the odds ratios (OR) and 95% confidence intervals (CI). Overall, 232 students (85.0%) continued to participate in sports clubs after April of their third year, and 41 students (15.0%) experienced early attrition. Statistically significant correlates for early attrition were weight (OR = 0.94, 95% CI = 0.90-0.98), body mass index (OR = 0.84, 95% CI = 0.74-0.97), experience of injury or disability (OR = 0.40, 95% CI = 0.19-0.87), athletic achievement (OR = 0.29, 95% CI = 0.13-0.62), and duration of experience of the sport (OR = 0.99, 95% CI = 0.98-1.00). Our findings suggest that the school officers or family members of students should recognize the possibility of early attrition and provide appropriate support if a student experiences early attrition. The athletic level or norms of school sports club activities may differ among other schools and sports clubs; therefore, it is necessary to examine whether our findings are applicable to other schools and sports clubs.

Sport activities for children and adolescents: the Position of the European Academy of Paediatrics and the European Confederation of Primary Care Paediatricians 2023-Part 1. Pre-participation physical evaluation in young athletes

The European Academy of Paediatrics (EAP) and the European Confederation of Primary Care Paediatricians (ECPCP) emphasize the importance of promoting healthy lifestyles within the pediatric population. Many health professionals have questions concerning adequate levels of physical activity for both the healthy pediatric population and for those who may have specific complications. Unfortunately, the academic literature that provides recommendations for participation in sport activities within the pediatric population that have been published during the last decade in Europe is limited and is mainly dedicated to specific illnesses or advanced athletes and not toward the general population. The aim of part 1 of the EAP and ECPCP position statement is to assist healthcare professionals in implementing the best management strategies for a pre-participation evaluation (PPE) for participation in sports for individual children and adolescents. In the absence of a uniform protocol, it is necessary to respect physician autonomy for choosing and implementing the most appropriate and familiar PPE screening strategy and to discuss the decisions made with young athletes and their families. This first part of the Position Statement concerning Sport Activities for Children and Adolescents is dedicated to healthy young athletes.

Early Sport Specialization Trends and Injuries in Former High School Athletes Specialized in Sports

Purpose

Determining the effects of early specialization in a specific sport is difficult. Therefore, it is necessary to investigate its effects based on the type of sports. The purpose of this study was to investigate the proportion of participants who had been participating in a single sport, in individual or team sports from an early age and to compared the prevalence of acute and overuse injuries among these participants.

Methods

A total of 1377 adult participants (team sports = 700, individual sports = 637) retrospectively completed a questionnaire assessing sports participation from elementary school to high school and injury history (acute and overuse) at high school age. The proportions of the specialized / nonspecialized groups per sport type were compared, and differences in acute or overuse injury prevalence were examined.

Results

The proportion of the specialized group participants who continued to play the same single sport from elementary school age to high school age was greater in team sports (33.6%) than that in individual sports (19.2%) (p < 0.01). The specialized group participating in team sports had a greater prevalence of overuse injury at high school age than the nonspecialized group (p < 0.05) who previously participated in several sports. However, the prevalence of overuse injury at high school did not significantly differ between the specialized and nonspecialized groups participating in individual sports.

Conclusion

More children who continued to play only one sport from elementary school age to high school age played in team sports in Japan. They also had a higher prevalence of overuse injuries when they were at high school age. It is necessary to consider the environment to play multi sports before high school age, especially in team sports.

Risk Factors of Sports-Related Injury in School-Aged Children and Adolescents: A Retrospective Questionnaire Survey

Studies conducting quantitative surveys in school-aged children and adolescents help identify sports-related risk factors for acute and overuse injuries are scarce. This study aimed to quantify the risk factors for sports-related injury in school-aged children and adolescents by school categories. University students (n = 484) retrospectively recalled their sports experiences and related injuries in a questionnaire according to the following school categories: lower elementary school (LE), upper elementary school (UE), junior high school (JH), and high school (H). Both sports-related acute and overuse injuries were recorded. After adjusting various covariates, weekly hours in sports were identified as a significant risk factor in LE and UE. The interaction of weekly hours in sports and sports specialization was significant in LE and UE, suggesting that early specialization would be a risk factor in lower school categories. In JH and H, female sex, high-level competition, and injury experienced in a previous school category were significantly related to sports-related injuries. In conclusion, weekly hours in sports, high-level competitions, previous injury experience, and sex were confirmed as risk factors in specific school categories. Most identified risk factors are modifiable, suggesting that sports-related injuries can be prevented in school-aged children and adolescents.

Association of Sports Participation and Training Frequency with Injury in Japanese Students Majoring in Physical Education: A Retrospective Analysis

Objectives: This study evaluated prior sports participation and training frequency during elementary to high school and their association with acute and overuse injuries in Japanese college students currently majoring in physical education.Methods: This retrospective study included 292 students who completed questionnaires that assessed their type of sport participation (single sport or multiple sports), training frequency (number of days per week), and injury history (acute and overuse) during the elementary, junior high, and high school periods.Results: In total, 47.9% (95% confidence interval [CI]: 38.2–57.7) of elementary school-aged athletes played multiple sports; this decreased to 22.3% (95% CI: 14.1–30.4) in junior high school and 5.5% (95% CI: 1.0–9.9) in high school. There was a significant difference in the training frequency between those who had overuse injuries and not in elementary (p < 0.05), and junior high school (p < 0.05).Conclusions: The results of this study suggest that participating in multiple sports through junior high school may lead to improved sports levels (i.e., participation in higher levels of competition). In addition, appropriate management of training frequency may help reduce the incidence of overuse injuries.