This study aims to investigate the influence of muscle mass on jump height based on the stage of biological maturation. The total sample consisted of 71 male athletes with three years of minimum training experience. The athletes were divided into three groups based on biological maturation: PrePHV, MidPHV, and PostPHV. Vertical jump height was assessed using three tests: the countermovement jump (CMJ), the countermovement jump with arm swing (CMJwas), and the squat jump (SJ). The results of the interaction between muscle mass percentage (MM) and peak height velocity (PHV) indicate that the effect of MM on vertical jump variables is greater in the PrePHV and MidPHV groups compared to the PostPHV group. For the PrePHV and MidPHV groups, there was a significant increase in CMJ [b=.83, t(22)=3.77, p=.001 and b=.92, t(14)=3.70, p=.002, respectively] and SJ [b=1.11, t(22)=4.45, p< .001 and b=1.06, t(14)=3.51, p=.003, respectively] when muscle mass percentage increased by one unit, while no significant increments were apparent for the PostPHV group [b=0.71, t=1.98, p=.058 and b=0.48, t(28)=1.65, p=.111, respectively]. Additionally, when muscle mass percentage increased by one unit, the CMJwas performance significantly increased in the PrePHV [b=1.48, t(22)=4.68, p<.001], MidPHV [b=1.15, t(14)=4.59, p<.001], and PostPHV [b=.97, t(28)=2.52, p=.018] groups. This study substantiates muscle mass as an important predictor of explosive power, demonstrating a more pronounced impact in the PrePHV and MidPHV relative to the PostPHV group. The study points out the importance of considering biological maturation when understanding the relationship between muscle mass and explosive power performance in young athletes.

Introduction: Taekwondo has developed into an Olympic sport, which means that a thorough understanding of the main Taekwondo athletes and competitors' characteristics is necessary. This study investigated the fundamental anthropometric measurements of high-level Taekwondo athletes, with a particular focus on disparities between genders. The objective of this study was to assess and contrast the physical attributes of elite Taekwondo athletes, specifically examining the differences between males and females. Methods: A group of 28 highly skilled Taekwondo athletes, consisting of 14 female and 14 male cadets participated in this study. Results: The results showed a significant difference between male and female competitors' anthropometric variables, most notably in skinfold thickness and fat tissue proportion (p≤ 0.01). Conclusion: Accordingly, these data can help taekwondo specialists in the early stages of selection, especially when advanced examinations are impossible. Further studies profiling this group of responders should include more characteristics to help practitioners recognize talents and create training program goals.

The aim of this research was to systematize the available literature on the types and frequency of locomotor injuries in combat sports. The sample consisted of martial arts athletes (judo, karate, wrestling, boxing and taekwondo) of both sexes, aged 11-49 years. Survey questionnaires and medical reports were used as measuring instruments for assessing injuries in the research. The found data, presented numerically and in percentages, were used for further analysis. The results of this research show that the characteristics of injuries of the locomotor system in martial arts usually do not depend on the sex of the respondents. There is a higher frequency of injuries in competitions and lower in training (except for under-18s). The most common locations of injuries (head and neck, extremities and joints), types of injuries (contusions, bruises and fractures), and severity of injuries (mild, moderate, or severe) depended on the characteristics of martial arts (sports techniques, tactics, physical and mental fitness, etc.). By applying additional methods, by improving physical preparation that is adequately dosed with the improvement of technical and tactical elements, injuries to athletes could be prevented.

High handgrip strength in men’s artistic gymnastics is crucial, mainly for improving performance and to potentially prevent injuries, as well as for the fact that gymnasts body movements are around immovable apparatuses (pommel horse, rings, parallel bars and high bar) for the extended period of time. Since there are not so many studies that have dealt with this topic and on actual competition, we have aimed to examine the handgrip strength influence on the competition result in elite male artistic gymnasts. The sample of participants were conducted of 37 elite male artistic gymnasts (8–21 years old), from 8 different countries as national team competitors at the International Competition “Laza Krstić and Marica Dželatović” held in Novi Sad, Serbia. Basic anthropometric measurements were included (body height, body weight and Body Mass Index (BMI)), along with training experience and handgrip strength measurement (both dominant and nondominant hand). Kolmogorov-Smirnov Z test (p < 0.05) was used for distribution normality, along with regression analysis with Model 1 (participants age, training experience, body height, body weight and BMI), Model 2 (Model 1 + dominant handgrip strength) and Model 3 (Model 1 + nondominant handgrip strength). SPSS v.20 was used for all statistical analysis. Our study have revealed that there is significant influence of all 3 Models on the parallel bars final result (p = 0.33; p = 0.49; p = 0.31, respectively), in terms of all set of variables, whereas body weight Beta scores (28.6%; 30.3%; 32.7%, respectively) moslty explains the results. Both dominant and nondominant handgrip strength are influential factors only on the parallel bars final result. Since both hands are contributing equally, bilateral training is necessary. In order to expand the knowledge on this topic and completely understand the influential factors, future studies are needed on this sample. Regardless of our main findings, our results should be taken with caution.

The aim of this research was to determine the differences related to morphological characteristics and body composition among female players of Montenegro national junior volleyball team and Kosovo national junior volleyball team. A sample of the subject consists of a total of 25 top-level female junior players who were members of two national teams, participants of the European Championship qualifying 2020. The first sub-sample of the subjects consisted of 13 players of National team of Montenegro, of the average age 17.13 ± 0.54, while the other sub-sample consisted of 12 players of National team of Kosovo, of the average age of 16.35 ± 0.41. Anthropometric characteristics in the body composition were evaluated by a battery of 11 variables: body height (cm), body weight (kg), triceps skinfold (mm), back skinfold, biceps skinfold, abdominal skinfold, thigh skinfold, calf skinfold, body mass index (BMI), percentage of fat (%) and muscle mass (kg). Statistically significant differences (p< 0.05) between body composition and morphological characteristic of the female volleyball players of two national teams, Montenegro and Kosovo, were determined by using a discriminatory parametric procedure with t-test for small independent samples. The results showed that the female volleyball players of Montenegro are somewhat higher, also they have greater body mass index, greater muscle mass and a significantly lower percentage of fat, compared to the female volleyball players of Kosovo. When it comes to variables of skinfolds, it was demonstrated only one statistical significance in favor of the Montenegrin National team, variable skinfold thigh.

This study aims to determine the effects of a program based on a progressive increase in the number of nage-komi repetitions (throws) on a specific judo fitness test (SJFT). The research was conducted on a total of 20 respondents. In SJFT for research purposes, 12 variables. Descriptive statistics and paired t-tests for dependent samples of initial and final testing were used for data processing. The results of the study showed significant statistical deviations in the number of throws in the first 15 seconds, with the pulse measured immediately after testing and the SJFT index (p <005). There is a noticeable need for a table to classify SJFT results for young judoists. Based on the obtained results, we can conclude that the programmed activity had positive effects on the results of the SJFT, ie that the index was statistically significantly lower in the final than in the initial testing. Taking into account the results obtained, calculated by the SPSS 22 t-test for dependent variables, the values ??of the young judoist index and the values ??of the senior index show noticeable differences. While their results can be classified into appropriate categories, the results of young judoists can be classifieclassifiedrity, under, ad and the rest as very bad. Some results could not even be ranked, so we conclude that it is necessary to make tables for classifying the results of young judoists. The obtained results can be used as guidelines for more efficient programming of the training process. Keywords: cadets, judo, juniors, SJFT test, training.

The aim of the study was to analyze the relationship between lifestyle level and the risk of type 2 diabetes. The study included 206 respondents who were not diagnosed with diabetes and who were not elite or amateur athletes. The sample was divided into two sub-samples. The first group consisted of respondents aged 18-29 years (n = 104); the second group consisted of respondents aged 30-44 years (n = 102). The FINDRISC questionnaire was used to collect data for the purpose of assessing the risk of type 2 diabetes. The answers to 8 questions provided information about respondent's age, body mass index, waist circumference, physical activity, fruit and vegetable consumption, high-pressure medication, history of hyperglycemia and history of diabetes in the family. The results of the type 2 diabetes risk level indicated the following values: a low level was present in 55%; mild level in 33%; moderate level in 8%; and a high level in 4% of respondents. The results of the study indicated that quality of life decreases with age and the risk of diabetes increases. Therefore, it is important to familiarize people with how to control their weight, their eating habits and their regular physical activity as a preventive method. It is also important to recognize and apply global animation models to maintain and improve the health status of people.

This research aimed to determine the isokinetic strength differences between two groups of athletes (karate and track-and-field athletics) and to analyse factors that possibly contribute to the differences. We examined possible differences in peak power output and power ratio between agonist and antagonist thigh muscles of the knee. The sample consisted of 20 respondents: karate athletes (n=10; age 19±2.4) and track-and-field athletes (n=10; age 18±2.6). For this study, a valid test (CV<5%) of the isokinetic strength output of the knee extensors and flexors, was used at the angular velocity of 60°/s. Isokinetic variables: Peak torque in extension for both legs (Nm); Peak torque in flexion for both legs (Nm); Total work for both legs (J); Strength deficit involved/uninvolved leg and agonist/antagonist ratio for involved and uninvolved leg. A t-test for independent samples was used to determine the differences. Statistical significance was set at the conventional 95%. In the sample of examined variables, the first tested group of athletes (karate) achieved higher power output values with the dominant leg, except in the case of the peak torque extensors. In the second tested group of athletes (track-and-field athletics), a higher power output values are registered with dominant leg, except in the case of the total work flexor with almost identical value of dominant and non-dominant leg. In the variables of the peak torque of the dominant leg (p=0.002) and the peak torque of the non-dominant leg (p=0.019), statistically significant differences were noted between two tested groups of athletes (p<0.01, p<0.05). The unilateral relationship of the dominant leg (p=.003) significantly differentiates two groups of athletes (p<0.01). The better performance of track-and-field athletes is probably the result of the specificity of the structure of their motor movement and greater muscular work in training and competition. In contrast, the lower results of peak torque and total work in karate athletes compared to track athletes do not necessarily mean situational inferiority. Evaluation and assessment of knee dynamic stabilizers’ isokinetic profile can lead to the optimal selection of training operators, during the construction of the overall training program for athletes. Results of different outputs of force and strength may indicate a differently shaped approach to training.

Uvod Poznato je da starenje za posljedicu ima opadanje tjelesnih sposobnosti čovjeka, što je uz globalni problem hipokinezije, jedan od vodećih savremenih problema društva (Čaušević, Ormanović, Doder, & Čović, 2017; Ćirić, Čaušević, & Bejdić, 2015). Individualni aerobni fi tness se smanjuje za 8-10% tokom svake decenije života, dok veoma aktivni ljudi mogu smanjiti ovaj nivo na 2-3%. Opadanje snage je osjetno u šezdesetim, a posebno u sedamdesetim godinama života (15% odnosno 30%), (Sharkey & Gaskill, 2008). Takođe u brojnim studijama, utvrđeno je da su promjene koje nastaju kao posljedica biološkog starenja, povezane sa smanjenim stepenom fi zičke aktivnosti osoba starije dobi, a koje za posljedicu imaju smanjenje mišićne mase i tjelesne funkcije. Poznato je da organizovano tjelesno vježbanje ima mnogo pozitivnih efekata na organizam čovjeka u cjelini, te da ima jasan i prioritetan fi zički i zdravstveni uticaj na osobe i njihove radne aktivnosti. Međutim, bez obzira na to šta osoba radi – bilo da se bavi prostim fi zičkim poslom (nošenjem, podizanjem, poljoprivrednim radom) ili vrši fi zičke vježbe, njen mišić ni, kardio-vaskularni, respiratorni i centralni nervni sistem aktivno funkcionišu. Shodno tome će fi zička aktivnost, bilo kao tjelesna vježba ili fi zički rad, uvijek uticati na naše tijelo i tako dovesti do poveć anog nivoa funkcionisanja (Bjelica & Krivikapić, 2019). S druge strane, neaktivnost uzrokuje 9% prerane smrtnosti, što brojem iznosi više nego 5,3 od 57 miliona smrtnih slučajeva širom svijeta tokom 2008. godine (Lee i sar. 2012). Istoimeni autori navode da ukoliko neaktivnost nije eliminisana ali jeste umanjena za 10% ili 25%, onda bi se smrtnost tokom svake godine mogla izbjeći za više od 533 000 odnosno za više od 1,3 miliona slučajeva. Ovakav navod potvrđuje i činjenica da Abstract

Uvod Dehidracija može ugroziti sportsku izvedbu i povećati rizik od teške tjelesne povrede. Negativni efekti dehidratacije na performanse se uočavaju već pri <2% (Barr, 1999). Naime, manjak tečnosti koji se javlja tokom jedne vježbe može potencijalno kompromitovati sljedeću sesiju vježbanja, ukoliko ne dođe do adekvatne zamjene tečnosti. Dakle, zamjena te čnosti poslije vježbanja često se može smatrati hidratacijom prije sljedećeg treninga (Shirreff s, Armstrong, & Cheuvront, 2004). Ipak, sportisti samoinicijativno ne piju dovoljnu količinu vode za sprječavanje dehidracije tokom fi zičke aktivnosti (Casa, Armstrong, Hillman, Montain, Reiff , Rich, Roberts, & Stone, 2000; Maughan i sar., 2010). Maughan & Shirreff s (2010), navode da neki sportisti piju previše tečnosti, dok neki mogu razviti i hiponatremiju zbog prevelikog unosa tečnosti. S druge strane, slobodnim mikropauzama koje se tokom treninga planiraju u cilju nadoknađivanja tečnosti gubi se na intenzitetu treninga, a ukoliko je cilj treninga sticanje motoričkog znanja onda dolazi do narušavanja organizacije i kontinuiteta rada (Gobson i sar., 2012). Pogotovo je to slučaj prilikom rada u parovima, kada jedan od partnera nadoknađuje tečnost, dok drugi stoji i čeka ga. Interesantno bi bilo ispitati da li nadoknađivanje tečnosti tokom treninga predstavlja samo naviku sportiste, ili zato zaista postoji objektivna potreba nastala kao rezultat gubitka tečnosti znojenjem i naprezanjem tokom treninga. Sam osječaj žeđi je individualnog karaktera, te bi stoga bilo potrebno provjeriti opravdanost slobodnog načina rehidriranja. Poznato je i da vrhunski judo takmičari hipohidracijom smanjuju težinu prije takmičenja, što takođe negativno utiče na organizam sportiste i dovodi do smanjenja funkcije te negativnih učinaka na zdravlje (Jung & Malliaropoulos, 2014). Gubitak tečnosti rezultira osjećajem letargije i gubitkom motivacije za nastavak vježbanja, pridonoseći razvoju umora (Watson, 2008). Kratkoročne promjene u hidrataciji mogu se procijeniti na temelju promjene mase tijela (Maughan & Shirreff s, 2010). Rezultati ove studije bi trebali potvrditi dehidraciju organizma u slučaju nekonzumiranja tečnosti tokom judo treninga, te ukazati na opravdanost organizovane rehidratacije u slučaju sportista 11-12 godina starosti. Abstract