There are a plethora of studies investigating agility in soccer; however, studies have rarely presented the reaction time in differentiating age groups in adolescent soccer players. We investigated age differences in reactive agility, speed, and change of direction speed (CODs), in a group of highly trained adolescent soccer players. A total of 75 adolescent male soccer players (aged 14–19 years) were recruited. The players were grouped based on their age to under 15 (U15; n = 27), under 17 (U17; n = 25), and under 19 (U19; n = 23) players. Players were tested for 5 m, 10 m, and 20 m sprint, CODs speed test, Illinois test, and reactive agility test (total and reaction time). Only the reactive agility test with a live tester (RAT live) and RAT live reaction time (RAT live RT) distinguished U19 from both groups, U17 (RAT live, p < 0.01; RAT RT live, p < 0.01) and U15 (RAT live, p < 0.01; RAT RT live, p < 0.01). Groups did not have different times for 5 m sprint, RAT light and RAT RT light, F = 0.472, 2.691, 1.023, respectively, p > 0.05. Moreover, a significantly slower average performance of sprint 20, CODs left and right, and Illinois was also observed in U15 as compared to U17 and U19 (p < 0.05). We can conclude that results in agility tests that include live testers can be a significant factor that differentiates between adolescent soccer players considering their age.

Studies dealing with the effectiveness of the Fédération Internationale de Football Association (FIFA) 11+ prevention program to improve performance outcomes in children aged < 14 years are limited. This study aimed to point out the effects of the application of short-term FIFA 11+ warm-up program on physical performance in young football players. Participants were 36 youth male football players, divided into a FIFA 11+ (n = 19; mean (SD) age: 11.15 (0.79) y) and a control group (CG: n = 17; age: 10.87 (0.8) y) and trained for 4 weeks. Before and after the training period, standing long jump performance, agility, repeated sprint ability, sit and reach, and "30-15" intermittent fitness tests were assessed. A mixed ANOVA showed significant differences between the groups in the standing long jump test (FIFA 11+: 5.6% vs. CG: −1.9%) in favor of FIFA 11+ over CG. Additionally, the FIFA 11+ performance of the Illinois agility test was significantly better compared to the CG performance (FIFA 11+: −1.9% vs. CG: 0.03%). The main findings of this study suggest that just 4 weeks of implementation of the FIFA 11+ improves physical performance compared with traditional warm-up routines in young soccer players.

The early detection and continuous monitoring of children’s motor competence levels and physical fitness is very important. The purpose of this study was to determine the differences in motor coordination of children enrolled in soccer and multisport activities. The participants of this study included 147 boys and girls (mean age 7.60 ± 0.85 years). The total sample of subjects was composed of two subgroups: children who were enrolled in organized exercise programs—multisports (n = 77), and children who were engaged in soccer training (n = 70). Motor coordination was evaluated with the Kiphard–Schilling body coordination test (KTK). Physical fitness was assessed with a 20 m shuttle run test, 4 × 10 m shuttle run test, standing long jump, and handgrip strength. The ANCOVA showed significant differences (p < 0.05) with large effect size between groups for tests hopping for height (d = 0.93), total motor quotient (d = 1.31), jumping sideways (d = 1.32), and moving sideways (d = 1.59), after adjusting for age and gender. There were no significant differences between groups in the physical fitness tests. It can be concluded that children enrolled in multisport activities have higher levels of motor coordination than children who are enrolled only in soccer. Therefore, multiple sport training programs should be considered and encouraged by parents, educators, and other training professionals.

There is a strong relationship between body composition and performance in male soccer players. This study aimed to display an optimal body height and weight, and body composition profile of male soccer players for four competitive age groups. This cross-sectional study included four groups: U-15 (n = 152), U-17 (n = 154), U-19 (n = 61), and seniors (n = 27). Body height and weight were measured under standard conditions, and the bioelectrical impedance analyzer (BIA) analyzed body composition. On average, soccer players in the U-15 group had significantly lower body height, weight, body mass index, skeletal muscle mass, fat-free mass, total body water and basal metabolic rate than U-17, U-19 and seniors, but a higher percentage of body fat than U-17 and U-19, p < 0.05. In addition, the results show significant non-linear increases in body height, weight and body composition as the age of soccer players increases, with the exception of the percentage of body fat mass, which tends to significantly decrease with age. The main findings of this study are that body fat mass remains stable and similar across all age groups, including in the senior squad.

Th is study aimed to investigate the eff ect of offi cial soccer matches on selected markers of muscle damage in U-21 soccer players. A group of 19 trained, healthy male soccer players from the junior category took part in this study. Blood samples were assessed pre-match and immediately aft er a match in response to a competitive (2×45 min) soccer match. Analysis was performed for muscle damage and infl ammatory markers. Signifi cant diff erences between two measures (before and aft er soccer match) exist in Aspartate-aminotransferase (AST), Lactate dehydrogenase (LDH), and Myoglobin. Plasma K + signifi cantly decreased aft er the match (p<0.05), whereas plasma Na + decreased slightly. Th is study showed that most selected markers of muscle damage were infl uenced by a soccer match. However, results remain inconsistent because of the infl uence of the type, duration, and intensity of exercise. Moreover, some markers show great variability among individuals.

This study presents an overview of current scientific articles that address the reliability and validity of the 30–15 intermittent fitness test (30–15 IFT) as an assessment of aerobic capacity, as well as its use in terms of training programming. The search for and analysis of papers was conducted in accordance with PRISMA guidelines. A database search was performed through PubMed, PMC, Med Line, Cochrane Library and ScienceDirect, as well as directly from the author who first presented the IFT 30–15. Type of study: research was included in this paper on condition that (i) the original scientific paper was available in its entirety; (ii) the IFT 30–15 was used to evaluate or verify validity and reliability; and (iii) the IFT 30–15 was used for the purpose of evaluation of training programming. Of the 213 relevant studies identified, 21 were included in the quantitative analysis. All research was conducted on a sample of athletes who are exclusively engaged in team sports. As for the use of the subject test when it comes to programming individualized intermittent training to strengthen aerobic capacity, it seems that the IFT 30–15 test is appropriate and extremely useful for team sports. Regarding the reliability of tests identified in the reviewed literature, all studies indicate that the 30–15 IFT is a reliable test for assessment of aerobic capacity.

The aim of this study was to examine seasonal variations in body composition in adolescent soccer players. A total of 64 young male soccer players (aged 14-18 years) were recruited for this research. Body composition was assessed using the Bioelectric impedance analysis. The variables were body mass, body fat, muscle mass, fat free mass, total body water, BMI, body fat %, basic metabolic rate. Body mass did not change across the three measurement occasions. Body fat mass and body fat % significantly changed between test intervals (p≤0.05). There were no significant differences in other variables between measurements performed during the season. In conclusion, body fat has changed significantly from the start of the season to the end of the competitive period in adolescent soccer players, in accordance with earlier studies.

sporta i fizičkog vaspitanja, Novi Sad, Srbija 2 Srednja škola -Grocka, Srbija Sažetak.Ispitivanje rodnih razlika u sposobnostima i karakteristikama od značaja za nastavu fizičkog vaspitanja, omogućava bolje planiranje i programiranje nastavnog rada. Cilj rada je bio da se utvrdi da li postoje statistički značajne razlike u morfološkim karakteristikama i motoričkim sposobnostima devojčica i dečaka mlaĎeg školskog uzrasta. Istraživanje je sprovedeno na uzorku od 70 ispitanika (36 dečaka i 34 devojčice), uzrasta 9-11 godina, učenika OŠ "Mića Stojković" u Umčarima. Primenjene su dve antropološke mere i osam motoričkih testova. Rodne razlike u morfološkim varijablama ispitane su ttestom za nezavisne uzorke, a u motoričkim varijablama pomoću multivarijante i univarijantne analize varijanse. IzmeĎu devojčica i dečaka nisu konstatovane statistički značajne razlike u telesnoj visini i masi. Primenom multivarijantne analize varijanse utvrĎe-no je postojanje statistički značajne razlike u motoričkom prostoru devojčica i dečaka. Na nivou pojedinačnih varijabli, značajne razlike su utvrĎene u varijablama: Trčanje 30 m iz visokog starta, Izdržaj u zgibu, Bacanje medicinke (1kg) iz ležećeg položaja na leĎima i Trčanje 6 minuta u korist dečaka, odnosno, u varijablama Odbijanje lopte od zid i Pretklon na klupici u korist devojčica. Dečaci su ispoljili značajno viši nivo snage, brzine i aerobne izdržljivosti, dok su devojčice bile uspešnije u testovima koordinacije i gipkosti. Dobijeni rezultati se mogu tumačiti razlikama u nivou fizičke aktivnosti devojči-ca i dečaka, zatim razlikama u telesnoj graĎi i strukturi, pažljivosti prilikom instrukcije i dr.Ključne reči: antropološke karakteristike, pol, deca, osnovna škola UvodFizički razvoj i fizičke sposobnosti su veoma važni višedimenzionalni pojmovi, čije definisanje i selekcija odgovarajućih parametara ima dugu i kompleksnu istoriju. Problem praćenja i vrednovanja različitih varijabli u ovoj oblasti zahteva naučno utvrđivanje celokupne sistemske strukture i definisanje onih dimenzija koje tu strukturu obeležavaju kao organizovanu celinu, jer su rezultati u oblasti fizičkog vežbanja uglavnom zanemarljivi, ako se ne izvrši kontrola i praćenje ovih procesa, uz objektivnu valorizaciju njihovih efekata. U procesu programiranja i sprovođenja sistema praćenja morfoloških i motoričkih sposobnosti dece i omladine, neophodno je prethodno određivanje nivoa, dinamike i strukture aktuelnih pojava koje su vezane za pol, uzrast, socijalne, etnografske, geografske i druge karakteristike. Međutim, morfološke i motoričke dimenzije na predstavlljaju izolovane faktore, već se moraju posmatrati u okviru celovitog sistema koji čini čoveka kao poseban biopsihosocijalni entitet, pa je samim tim njihova ekstrakcija i merenje otežano.Autor za korespondenciju: Miroslav Smajić,