This research aimed to propose a new methodological approach for analyzing relative age effect (RAE) in different sports or samples named “Relative age effect overall scale” (RAEOS). The sample consisted of 1455 male and female young athletes who competed in four different sports (basketball, n = 159; handball, n = 215; swimming, n = 981; taekwondo, n = 100) at the Youth Olympic Games (YOG) in Buenos Aires in 2018. To construct the new model, the sample was classified into four unified quartiles of a specific range depending on the sport (swimming: 48-month range, taekwondo: 24-month range, and basketball and handball: 36-month range). Expected and observed frequencies for each sport, the winners/all athletes, and differences between team and individual sports were analyzed using a non-parametric Chi-square test. The obtained results confirm the existence of the RAE in all four analyzed sports (p > 0.01) in a sample of all participants and the sample of gold medalists. Differences between team and individual sports in the analyzed sample have also been found. The proposed methodological approach (RAEOS) is a simple and applicable tool that provides opportunities for comparison and analysis of different sports and competition formats, as well as improvement of the sports talent system in the context of RAE issues. It is suggested to the sports decision-makers to improve the YOG qualification and competition system to enable fairer competition and reduce the influence of RAE on the performance and development of young athletes.

Aggression and violence among youth are researched as social phenomena in sport. This paper was designed to determine the occurrence of these behaviors as well as prosocial behaviors among young athletes. The current paper is a research report aiming to detect the frequency of aggressive behavior, social exclusion, prosocial behavior and cohesion in the youth environment, the frequency of personal experience of peer violence or social exclusion, and to evaluate cross-national differences in terms of occurrence of these phenomena.The field research was conducted in six European countries (Austria, Bosnia and Herzegovina, Croatia, Italy, Lithuania, and Serbia) on a sample of 482 children aged 6 to 16. The conducted questionnaire consisted of pre-existing scales and measures for specific behaviors and social aspects that formed the Youth Environment Assessment and Youth Characteristics Questionnaire. Previous personal experience of violence and social exclusion determined groups in the sample. One-way ANOVA and discriminant analysis were conducted to compare various variables and groups within the sample. The results have shown that aggressive and social exclusion behaviors are rare or very rare, predominantly in the form of verbal aggression in the sports club environment. The results of the conducted discriminant analysis indicate that prosocial and cohesion behaviors occur “quite often” to “often” among sports club athletes’ samples. The percentage of athletes who have had personal experience of violence or social exclusion in the last two years and whose feeling of hurt by that experience was assessed as “a lot” or “fully” on the measurement scale is estimated to be approximately 25%. Mild cross-national differences emerged in the overmentioned variables, probably due to the sample specificity, or to cultural variety. The results indicate the need for longitudinal research on this topic since the sport is an environment in which cohesion can be developed among young athletes, but it is not free from social exclusion or aggression.

The main purpose of this study was to determine the body composition and anthropometric reference values of male and female junior Croatian taekwondo competitors according to official weight category. Additional aim of the study was to identify possible differences in variables between the weight categories. The sample comprised 247 junior participants of the national taekwondo championships divided into male (N=121) and female (N=126). The variable sample was defined by a set of 8 measurements: Body height (cm), Body mass (kg), Body mass index, Body fat (%), Body fat (kg), Muscle mass (kg), Lean body mass (kg) and Total body water (%). Results confirm previous studies proving that younger taekwondo practitioners have higher levels of body fat than their more experienced peers (seniors). Significant differences were only found between lean and heavy categories. Male junior taekwondo athletes show total body water percentages from 57.4 to 74.8 %, with significantly lower percentages in higher weight categories, while female athletes in heigher categories demonstrate a worrying level of hydration status, therefore endangering their performance and overall health. As the first paper that investigates the reference values of junior taekwondo athletes but based on official weight categories it is especially important as each weight category warrant different body composition requirements, as seen from significant differences across different variables. Future studies should include motor abilities inspection throughout the weight categories and possible use of calculation of metabolic age.

Purpose: This study aims to investigate the level of lower-limb functional asymmetries in sub-elite rhythmic gymnasts while performing sport-specific elements, including passe and side passe balance stance. Methods: The analysis focuses on postural stability and balance parameters, measured using Gyko, a 3-axis accelerometer, gyroscope, and magnetometer device. The task was to execute a passe balance and maintain the position for 30 seconds, which was the duration of the test, and then perform the same task with the other leg. The test was repeated for both legs in a side passe balance stance. Sixteen active female sub-elite rhythmic gymnasts participated in the study. Results: The results reveal significant differences in the mean travel velocity in all anatomical planes during the passe elements, indicating asymmetry in postural stability in favor of the non-dominant leg (P≤ .01). Similarly, in the side passe balance test, significant differences were observed in the mediolateral (in favor of the dominant leg) and anteroposterior (in favor of the non-dominant leg) total distances, indicating asymmetry in postural stability (P= .03). However, no significant differences were found in other postural stability parameters, the ellipse (EA) and the total length of the trajectory (Len(D)). Conclusions: Evident asymmetries in movement speed during the passe element and imbalances in weight distribution during the side passe balance test do not appear to compromise overall postural stability considering that asymmetry was not proven in several variables, such as the ellipse or the total length of the trajectory. These findings shed light on the potential impact of asymmetries on performance and injury risk in rhythmic gymnastics, emphasizing the importance of considering sport-specific balance tests.

The objectives of this study were: a) to examine the influence of an 18-week basic artistic gymnastics program on fundamental movement skills (FMS) development in seven-year-old children; b) to determine correlations between children’s daily activities and successful performance of FMS and basic artistic gymnastics skills. Seventy five first grade primary school children took part in this study. A physical education teacher specialized in artistic gymnastics conducted a gymnastics program for 18 weeks, three times a week. The level of gymnastics skills and FMS were identified at the beginning and at the end of the program. The level of gymnastics skills was evaluated by performance of eight artistic gymnastics skills, while FMS were evaluated by the use of FMS-polygon. Physical activity and inactivity was evaluated by using a proxy-questionnaire “Netherlands Physical Activity Questionnaire˝ (NPAQ). According to the dependent samples t test, significant differences were found in the FMS-polygon and all gymnastics skills before and after the 18-week gymnastics program. Increasing correlations were established over time between gymnastics skills and the FMS-polygon. Unorganized daily activity of children significantly correlated with their mastering of gymnastics skills and FMS. The presented findings confirm: (1) the thesis that basic artistic gymnastics skills and FMS could be developed simultaneously, (2) the theory of positive transfer of similar skills between FMS and artistic gymnastic skills. Mastering basic artistic gymnastics skills will provoke improvement of FMS and finally become a prerequisite for successful introduction of learning more complex gymnastics skills. The obtained results imply that an increase of children’s unorganized daily activities can improve the mastering of basic gymnastics skills and simultaneously the development of FMS.

The purpose of this study was to identify pain occurrence among young female athletes in aesthetic sports by defining the proportions of pain status of fourteen body regions. Three groups of young female athletes (artistic gymnasts, rhythmic gymnasts and contemporary dancers) were analysed and compared. The sample consisted of overall 99 competitive athletes. Using the “Self-estimated functional inability because of pain” (SEFIP) questionnaire, athletes were asked to assess their current pain status in 14 body regions on a 5-point scale, with 0 being no pain and 4 being pain so severe that they are unable to practice. According to the Wilk’s test there was a significant multivariate effect (F= 4.60; p<0.001) between artistic gymnasts, rhythmic gymnasts and compulsory dancers in training experience and body status. The most common locations for incidence of pain on the total sample of subjects were in the lower back (44%), knees (35%) and ankles/feet (31%). Artistic gymnasts mostly report pain in the ankles/feet (51.43%), and lower (37.14%) and upper back (34.29%). Rhythmic gymnasts of the same age mostly report pain in lower back area (46.42%), knees (42.86%) shins, ankles and feet (28.57%)¸ while dancers experience pain mostly in lower back (50%), upper back (44%) and knees (38.89%). According to the results of the Chi-square test, artistic gymnasts reported significantly higher pain incidence in ankles/feet region (p<0.01). Early detection of even low intensity pain, accompanied with the adjustment of training load and usage of appropriate safety requirements, can prevent the occurrence of injuries among young athletes.