This article represents a review of the existing literature on possible long-term effects of sport participation at high-level on health. Search of databases was performed through Web of Science and Science Direct including following keywords: metabolic risk factor/syndrome, diabetes mellitus and cardiovascular health. Former athletes tend to adopt healthier lifestyles, which may give them an advantage in relation to risk factors taking into account metabolic risk factor/syndrome, diabetes mellitus and cardiovascular health. Health benefits of physical activities, moreover, depends of engagement at recommended levels, even in subjects who have never been athletes. 

The aim of this research was to examine in which way the constructs of emotional intelligence and perfectionism predict mental health of adolescent football layers. The sample consisted of 164 participants (average age 16.63 (± 10,21) years). The research was conducted in April 2018 and it included the cadet football players from KolubaraMacva league in Serbia. Test of Emotional Management (TUE; Babić-Čikeš i Buško, 2014), Multidimensional Perfectionism Scale (MPS; Frost et al. 1990) and Mental Health Inventory (MHI-38; Veit & Ware, 1983) were used to generalize data. During the process of data analysis, metric characteristics of the measuring instruments were first tested using the method of internal consistency which was based on Cronbach's alpha coefficient. The empirical findings of the correlation analysis revealed that there is no link between emotional intelligence and mental health of football players, meaning that managing emotions is only linked to adaptive dimensions of perfectionism (p ≤ 0,01). The obtained coefficient of multiple determination (R = 0.27) indicated that the group of predictors accounted for 27% of the variance of mental health, meaning that the perception of non-adaptive traits of perfectionism: (a) worry about mistakes, (b) dilemmas regarding one’s own actions and (c) parental criticism contribute the higher number of mental health problems. In addition, it showed that the adaptive trait of perfectionism (organizational skills) directly contributes better mental health of cadet football player. The results of this study suggest that the variables of emotional intelligence and perfectionism have significant role in prediction mental health among adolescent football players. 

The aim of this research was to determine the differences in health-related fitness between preschool children involved in organized and unorganized physical activities. This study was performed on a sample of 220 healthy preschool children that were divided into two groups, organized physical activity group (N=99) and unorganized physical activity group (N=121). Beside the set of anthropometric variables children were tested for Standing broad jump, Classic sitand-reach test, Bent arm hang, Sit-ups in 30 seconds and Handgrip strength test. The t-test applied to determine differences between anthropometric characteristic revealed differences for almost all variables (p≤0.05). Moreover, the organized physical activity group showed better results in all fitness variables compared to unorganized group (p≤0.01). It can be concluded that the developmental gymnastics program has influence on improvement of health-related fitness in preschool children.

Studies concerning the effects of different invasion games on physical fitness in school children are scarce. Consequently, the purpose of this study was to examine the effects of the application of invasion games on physical fitness in primary school children. A total of 62 primary school children aged 10-12 years voluntarily participated in this study. They were divided into experimental (32) and control (30) group. Physical fitness of children was estimated by the following tests: Standing broad jump, Vertical jump, Bent-arm hang, Sit-ups, Push- ups, Medicine ball test and Andersen test. The experimental group had twice per week invasion games on non-consecutive days for 12 weeks. Participants in control group did not perform specific program but attended their regular PE class twice per week. Compared with initial measurement, there was a significant (p < 0.05) improvement in vertical jump test for both groups. Furthermore, the group that participated in the invasion games program made significantly greater gains compared to the control group (p < 0.05) in Standing broad jump (8.2%; ES=0.56 vs. 3%; ES=0.2) and Medicine ball test (8.2%; ES=0.6 vs. 3%; ES=0.3). There was a significant improvement in bent arm hang, sit ups and push-ups in experimental group. Compared with initial measurement, there was a significant (p < 0.05) improvement in Andersen test in invasion games group, which was not the case with control group (p>0.05). To conclude, invasion games were an effective way of improving physical fitness in primary school children, because the results of this study indicate that this method was more effective for physical fitness than traditional school program. 

Measuring of morphological characteristics and motor abilities was performed on the sample of 51 male students of the secondary traffic school “Pinki” from Novi Sad.  Body height and body mass were used for measuring of morphological characteristics, and results of standing long jump and running at 30 meters with standing start were used for measuring of motor abilities. The body mass index was calculated after the results were obtained. The aims of the study were to establish and analyze differences in the results of morphological status and explosive strength of students measured in different periods, in the first measurement when the subjects were 15 years old and in the second measurement when the subjects were 17 years old. The data obtained in the study were analyzed using repeated measures ANOVA. The obtained results indicate the existence of statistically significant differences between first and second measurement in all morphological characteristics and motor abilities, at the level of significance of p<0.05.A significant increase in morphological characteristics and motor abilities with age, indicating that boys have adequate growth and development for their age.The age factor has a significantly stronger influence than the factor of the curriculum for the physical education in this high school. 

The aim of this paper was to determine whether the high-intensity interval training (HIIT) training can improve aerobic fitness in regional-level soccer players. Billat method (30-30s and 15-15s; 6-12 min) was used twice a week for 8 weeks during a season. Twenty-Three National-level soccer team players, (years=25±8, height=183.28±5.93, weight=75.28±5.9), were recruited for this study. Pre- and post-experimental period, maximum oxygen uptake was measured thru pseudo-ramp test on treadmill until volitional fatigue. Obtained results showed improvement in aerobic fitness for post- vs premeasurement (initial measurement = 51.92±3.40, final measurement = 54.87±2.61, p<.001). It is likely that specific high intensity interval training is viable method for aerobic fitness improvements in national-level soccer players when conducted during season.

The aim of this research was to examine differences in the use of self-handicapping strategies in athletes and non-athletes, changes in self-handicapping strategies that can occur with the approach of an important event, and the relationships between these strategies and personality traits, gender, and some external criteria such as performance. The sample included 183 subjects (mean age 21.16 years) consisting of 102 non-athletes and 81 athletes. Three questionnaires were used: VP+2, for measuring personality dimensions of seven-factor model, SH-17, for the assessment of changes in the use of self-handicapping strategies through time and a general biographical questionnaire. A general linear model for repeated measures was used for data analysis. Significant correlation was found between self-handicapping strategies and the number of medals and awards won at international and domestic competitions. The results also showed a positive correlation between self-handicapping strategies and dimensions of Neuroticism and Extraversion and negative with Conscientiousness. Also, a statistically significant difference in the use of self-handicapping strategies was found between athletes and non-athletes, showing that non-athletes express more self-handicapping behaviour. The results indicate that the frequency of selfhandicapping behaviour does not change through time. The effect of gender on self-handicapping is not significant, but there was a statistically significant interaction effect of gender and population on self-handicapping behaviour. It indicates that male non-athletes are more prone to self-handicapping 10 days before an important competition (exam or public speaking for general population, or “game of the season” for sporting population) compared to male athletes. These results, apart from the gender differences, are consistent with the results of previous studies. Limitations of this research and possible directions for future studies were also considered. 

The aim of this study is to establish the effects of specially programmed circuit training on physical fitness in primary school children. A total of 58 (28 girls) primary school children aged 11-13 (experimental group 12.2±1.2, control group 12.4±1.1) years voluntarily participated in this study. Physical fitness of children is assessed based on motor skills, through the following tests: abdominal muscle endurance - Sit-ups test, upper body strength and muscular endurance - Bent-arm hang test, upper-body muscular endurance - Pushups test, muscular strength and power of the lower limbs - Standing broad jump test, agility and speed - 4x10m test and flexibility - Sit and reach test. During the regular classes of physical education, the experimental group conducted a circular training lasting 15-20 minutes, at the same time control group practiced exercises that were in accordance with the plan and program of teaching physical education for a particular teaching unit. The treatment lasted for 15 weeks, with two classes of physical education per week. The results for the standing broad jump indicated significant differences between groups following 15 weeks. Furthermore, the group that participated in the circuit training program made significantly greater gains compared to the control group (p<0.05) in bent-arm hang, sit-ups and sit and reach. The results for the 4x10m test indicated no significant differences in time, group and their interaction (p≥0.05). To conclude, circuit training appears to be an effective way of improving physical fitness in primary school children. The results of this study indicate that this method was more effective for performance than traditional school program. 

The aim of this study was to establish the genderrelated differences among children 6-6.5 years of age in anthropometric characteristics so as to observe their development and make more appropriate selection for participation in guided and organised physical activities. A battery of 7 anthropometric measurements was used on the representative sample of 175 subjects of both genders from Valjevo (M=45 aged 6 and M=83 aged 6.5; F = 44 aged 6 and F=43 aged 6.5). The multivariate analysis of variance showed the existence of statistically significant differences (p=0.00) in the anthropometric space of the two ages analysed regarding the gender. Through the individual analysis, the differences at age 6 were found in the Upper arm skin fold variable (p=0.03) and the Back-skin fold (p=0.00), whereas with the 6.5-year-old subjects, the differences were found in the Body height variable (p=0.03), Upper arm skin fold (p=0.00) and Back skin fold (p=0.02), both in favour of the boys. It can be assumed that the differences are the result of the endogenous and exogenous factors upon the children's organism in the period of childhood in a smaller urban community of the southwest Serbia. 

The main purpose of our article was to broaden the knowledge of the level of the motor performance of young soccer players in puberty, taking into account their biological age. The object of our research was 18 soccer players in the U 15 category of the soccer club ŠK Slovan Bratislava divided into a subset with accelerated development (n=10) with body height 177,4 ± 5,1 cm, body weight 65,8 ± 7,5 kg and a subset with retarded development (n=8) with body height 170,9 ± 7,3 cm, body weight 63,9 ± 7,7 kg. To assess the motor performance, a set of 3 tests to evaluate speed and speed-coordination (agility) capabilities was applied. The set of tests contained a 10 m run (n=10 - average value of 1.61 s, n=8 - average value of 1.62 s), a 30 m run (n=10 - average value of 4.13 s, n=8 - average value of 4.16 s) and a 5 x 10 m run with a change of direction (n=10 - average value of 11.55 s, n=8 - average value of 11.70 s). Using the Mann-Whitney U test, we did not confirm in our case a statistically significant different level in the motor performance of the monitored sets with regard to the degree of their biological maturity.