Nebojša Trajković

University of Nis | NIS · Faculty of Sport and Physical Education

Background/Objectives: The aim of this study was to examine the acute effects of foam rolling and traditional stretch treatments on physical performance and self-perceived fatigue in youth football players. Methods: The sample of participants consisted of 20 youth football players from the Serbia Under-17 league. Participants were randomly assigned...

Background: The aim of this study is to investigate the effects of a school-based high-intensity interval training (HIIT) program on quality of life and physical fitness in adolescents. Methods: The study included 60 male adolescents (16.2 ± 0.6 years), randomly assigned to one of two groups: the HIIT group (n = 30) and the control group (CG, n = 3...

Background: The purpose of this study was to compare the effects of resistance training on stable versus unstable surfaces on strength performance in young judokas. Methods: The study included 18 young judokas (age: 13.2 ± 1.2 years) with 4.7 years of training experience assigned to either the URT (unstable resistance training) group or the STG (st...

Background/Objectives: This study aims to investigate the daily variations in upper and lower body power performance in adolescent volleyball players. Methods: The sample consisted of 50 young male volleyball players (14.12 ± 0.8 years), actively involved in regular training and competition. Players were tested for vertical jump tests and medicine...

Background High-intensity interval training (HIIT) in school settings has been much less studied in adolescents. The aim of this study was to examine the impact of HIIT on health-related fitness in adolescents. Methods The total sample consisted of 60 adolescents (age 16.33 ± 0.62 years) from secondary Grammar school, randomly divided into two gro...

Background/Objectives: The aim of this research was to determine the differences in physical fitness according to the level of physical activity (PA) during physical education classes in 10-year-old school children. Methods: The research included 315 primary school children (age 10 ± 1.3 years), divided into three groups by level of PA: low, modera...

Background: The relationship between motor coordination and physical fitness in preschool children is of significant interest due to its implications for overall health and development. This study aims to investigate the correlation between gross motor coordination, as assessed by the Körperkoordinationstest für Kinder (KTK), and health-related phy...

This study aimed to determine the influence of body composition on the muscle fitness of selected judokas. This study was conducted on a sample of 23 judokas (cadets n = 12, juniors n = 11), members of the male national team of Serbia. The assessment of body composition was performed using the InBody 720 (Biospace Co., Ltd., Seoul, Republic of Kore...

Background Individuals with type 1 diabetes mellitus (T1DM) face impaired cardiorespiratory fitness and glycemic control, increasing the risk of cardiovascular complications. High-intensity interval training (HIIT) has emerged as a promising exercise modality with potential benefits for both aspects in this population. Objectives The primary aim w...

Body composition is a fitness component closely associated with health and the efficiency of sports performance, making it an integral aspect of research in sports medicine sciences. Implementing appropriate training programs results in suitable physiological adaptations and a notable enhancement in body composition. This study determined the effec...

Background Although previous studies have reported that proprioceptive training methods (PTM) have positive effects, there is a relatively small number of studies regarding the impact of PTM in women’s soccer. Therefore, there is a need to systematize the given results. In this regard, this systematic review aimed to investigate the effect of propr...

The aim of this study was to determine inter-instrument reliability between Takei and Jamar dynamometers in school children. Fifty-six five grade participants aged eleven to twelve (n = 32 boys, n = 24 girls) performed handgrip strength test on two different occasions, with a 5-day gap between them, as test–retest. The Pearson correlation coefficie...

This study aimed to investigate the relationship between attitudes, motivation, and school sports engagement frequency, using the newly constructed Attitudes and Motivation Toward School Sports Questionnaire (AMTSSQ) inventory as a tool for assessment. The study found a significant effect of attitudes (F = 11.96, p < .001, np² = 0.02) and motivatio...

The COVID-19 pandemic has profoundly impacted global health, affecting millions of individuals worldwide. The pandemic has posed significant challenges to public health and profoundly influenced the fitness and overall health of individuals worldwide. The main objective of this study is a training programme that will offer quality and systematic tr...

Testing physical fitness in children is essential for monitoring their physical development. The goal of this study was to determine whether there are variations inphysical fitness test results throughout the day among primary school-aged children.A total of 60 primary school children (26 girls and 34 boys), aged 10 to 12, voluntarily participated...

Background Although previous studies have reported that proprioceptive training methods (PTM) have positive effects, there are a relatively small number of studies on the impact of PTM in women's soccer, and there is a need to systematize the given results. In this regard, this systematic review aimed to investigate the effect of proprioceptive tra...

Background There is limited information regarding adaptation of HIIT in female athletes which is important since the adaptation to HIIT may be different compared to male athletes. Therefore, the aim of this systematic review was to summarize the effects of HIIT on physical performance in female team sports athletes. Methods The following databases...

Motor coordination has a crucial role in various physical activities and sports, highlighting its significance in overall movement proficiency and performance. This study aimed to compare motor coordination in children engaged in multisport versus swimming activities. The participants of this study included 180 boys and girls (girls = 87) aged 8.25...

Background: This study aimed to explore the effectiveness of a 12-week circuit training program in improving local muscular endurance in normal-weighted primary school students. Methods: The study involved a parallel-group randomized trial with 606 primary school boys assigned to an experimental or a control group. The participants underwent a 1...

The aims of this study were to determine the relationship between vertical jumping performance, linear speed, change of direction speed (CODs) time and the COD deficit (CODD) in adolescent basketball players and to analyze the CODD between faster and slower players based on linear speed performance. Thirty-eight male basketball players (age: 15.47...

Background: The aim of this study was to examine the sodium bicarbonate (NaHCO3) effect on recovery in high-level judokas. Methods: The sample of participants consisted of 10 male judokas (Age = 20 ± 2.1 years) who are judo masters (black belt holders) with a minimum of 10 years of training and competition experience. The study was designed as a...

Since knowledge possession about the morphological characteristics trend is important to understand, it is necessary to monitor the physical growth and children's development. We have aimed to examine the current state, dynamics, and direction of changes in morphological characteristics, over a 30-year period in Serbian children and adolescents. Mo...

Musculoskeletal fitness (MF) is a multidimensional construct that combines muscle strength, endurance, and power to allow for the performance of tasks against one’s own body weight or an external resistance. The aim of this study was to determine the effects of school-based programs on promoting MF in children aged 6 to 10. PubMed and Web of Scienc...

Background: Plyometric training is used to improve human neuro-muscular function and performance in sports. Agility as a necessary motor ability, which is one of the physical components of success in many sports, is especially important for the optimal performance of soccer players. Due to changes in direction and movement during the game, soccer p...

The aim of this study is to determine the attitudes (level of anxiety about the pandemic and behavior caused by the pandemic) of athletes and staff members (coaches, physiotherapists) engaged in polystructural contact sports (wrestling) towards COVID-19. The sample of respondents consisted of 154 national team members and wrestling staff. The sampl...

It is well known that good postural stability and trunk flexibility are among the most important prerequisites for enhancing sports performance and achieving superior results [1,2,3]. In rowing, one or several athletes in a sitting position propel the boat through water via cyclical manipulation, which renders their posture unstable [4]. Consequentl...

Background: After the in-season period where trainings and games are consistant, players have the rest period, during which the volume and stress are reduced, which allows physical and mental recovery. Instead of having too much free time in transition period, the players should work on their fitness, in order to reduce the side effects of inactivi...

Background and Study Aim: Success in wrestling depends on many different factors, but strength could be considered as the most important one. Different strength indicators are closely related to high-level wrestling performance. The aim of this review is to generalize the recommendations of the authors of works dedicated to the analysis of muscle s...

This study aimed to investigate the effects of ten weeks of mixed resistance training on isometric force parameters and anthropological characteristics in young female adults. Fifty-two participants (22.61 ± 1.86 years) were randomized into either the mixed resistance training (MRT; n = 25) or control group (CON; n = 27). Anthropological parameters...

Caffeine supplementation has become increasingly popular among athletes. The benefits of caffeine include delaying the negative effects of fatigue, maintaining a high level of physical and mental performance, and improving certain abilities necessary for sport success. Given the complex nature of basketball, caffeine could be a legal, ergogenic sti...

The purpose of this study was to present the physical performance of elite female soccer players and to analyze the relationship between jump performance, speed and COD ability. Sixteen elite female soccer players (age: 20.05±2.85; height: 166.47±4.83cm; body weight: 60.52±8.30kg, BMI 21.88±2.86) from a women's club who played the highest rank of t...

The main aim of this study is to examine age and gender differences in cardiorespiratory fitness (CRF) among Serbian secondary school children. The secondary aim is to explore the association between CRF and quality of life in Serbian adolescents. The sample consisted of 579 adolescents (285 males), aged from 14 to 18 years old. To evaluate their a...

This study aimed to determine if there is a difference in postural stability in highly trained adolescents and young adult athletes regarding sex and sport. The participants were young athletes (n = 464) from seven different sports. We considered the center of pressure (CoP) velocity (total, anterior–posterior (AP) and medial–lateral (ML)), CoP amp...

The aim of this study was to establish the role of maturation on the development of physical performance in adolescent athletes and nonathletes. The total studied sample consisted of 231 participants (131 athletes: 72 boys with an average chronological age of 13.53 ± 0.7 and 59 girls with an average chronological age of 11.97 ± 0.8; 100 nonathletes...

This study aimed to determine the interrater and intrarater reliability of EasyForce dynamometer for assessing shoulder, knee, and hip muscle strength in healthy young adults. Shoulder, knee, and hip maximal isometric strength were measured using the EasyForce in healthy adults (11 women and 12 men). Three repetitions of shoulder internal rotation,...

The aim of this study was to determine the effects of a twelve-week game-based school intervention on physical fitness in girls aged 12–14 years. Fifty-nine adolescent girls (13.2 ± 0.3 years) were randomly assigned to a group that participated in a game-based after-school program (EXP) or a control group (CON) that participated only in mandatory p...

The prevalence of cognitive impairment in hemodialysis (HD) patients is extremely high. Despite the well-documented benefits of interventions on cognitive function, there is a widespread call for effective strategies that will show the long-term consequences in patients undergoing dialysis. The aim of this research protocol was to investigate the e...

BACKGROUND: The isokinetic testing can provide valuable information in combat sports regarding the strength of certain muscle groups and its imbalance detection. This study aimed to determine the isokinetic profile of shoulder internal and external rotators in judo and karate male elite athletes. METHODS: This cross-sectional study involved 22 elit...

This study aimed to assess intra- and inter-visit reliability of a novel EasyForce dynamometer for assessment of maximal strength in knee extension and flexion, and hip abduction and adduction tasks. Young healthy participants (n = 50; 25 males, 25 females; age: 23.4 ± 2.1 years) were measured for maximal joint torque with EasyForce dynamometer and...

The current study aimed to investigate the effects of an after-school volleyball program on body composition in overweight adolescent girls. Forty-two girls were randomly divided into a volleyball group (VG) (n = 22 age: 15.6 ± 0.5 years) and control group (CG) (n = 20; age: 15.5 ± 0.7years). Both groups continued with their usual physical educatio...

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 se...

The recovery of athletes following training is a constant concern for coaching staff since inadequate recovery can lead to chronic fatigue, decreased performance and increased potential for injury. Hyperbaric oxygen therapy is a treatment where 100% oxygen is administered under pressure, where the primary function is to accelerate the recovery of s...

Introduction: The ability to differentiate players according to their level is not clearly defined. There is evidence that youth soccer players classified as elite and non-elite differ in body size and maturity (Malina, 2003). but also in strength, flexibility and soccer-specific skills (Hansen et al, 1999; Rosch et al., 2000). However, studies t...

The study aimed to determine the effects of 6 months daily physical activity on physical fitness in preschool children. A total of 72 children (36 boys) and 92 children (47 boys) composed the experimental (EG) and control group (CG), respectively. We used the PREFIT battery access physical fitness. In EG, participants had 45 minutes of organized ph...

Motor skill competence of children is one of the important predictors of health because if a child is physically active during early childhood, the possibility of occurrence of many chronic diseases in adulthood will be reduced. The aim of this study was to systematically review the studies conducted in healthy children using the shorter form of th...

This study summarized the relevant literature and aimed to determine the effect of exercise-based interventions after myocardial infarction in middle-aged and older adults. Studies were identified and analyzed according to the PRISMA guidelines. The following electronic databases were used: Google Scholar, PubMed, Mendeley, Science Direct, and Scop...

Knee pads have become increasingly popular among volleyball players. Given the fact high-intensity activities that are crucial to successfully playing this sport lead to an increased risk of a knee injury, the primary use of knee pads is to prevent potential injury. However, no research has been carried out to explain the effects of knee pads on th...

Neuromuscular fatigue is known to impair balance ability, which is reflected in increased postural sway during quiet standing tasks. Recently, quantifying transient characteristics of postural sway has been suggested as an approach to obtain additional information regarding postural control. However, this approach is currently vastly unexplored. Th...

The aim of this research was to determine the difference in physical performance of soccer players across different playing positions in team. A total of 75 adolescent male soccer players (aged 14.2±0.4 years) that participated at the highest level of competition in Serbia of their age were recruited. They were tested for speed, change of direc...

The present study is aimed at determining the effects of intensity-modified recreational volleyball training on health markers and physical fitness in healthy middle-aged men. Thirty-four healthy untrained men aged 25–55 years were randomized to either a modified recreational volleyball group (MRV, n=17) or a recreational volleyball group (RV, n=17...

The purpose of the present cross-sectional study was to examine dietary patterns and the prevalence of underweight, overweight, and obesity among Serbian children. Furthermore, the study analyzed the association between dietary patterns and weight status. A nationally representative sample of 6–9-year-old children (n = 3,067) was evaluated as part...

The aim of this study was to determine the relationship between strength of ankle plantar and dorsal flexors and range of motion (RoM), and body sway variables during single-leg quiet stance, in highly trained athletes. The participants for this study were young athletes from 9 disciplines (n = 655). Center of pressure (CoP) velocity, amplitude, an...

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...

The aim of the study was to examine changes in obesity prevalence among primary school children in Serbia between 2015 and 2019 rounds of the national WHO European Childhood Obesity Surveillance Initiative (COSI-Serbia). Cross-sectional studies were conducted in 2015 and 2019. The nationally representative samples of primary school children were me...

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 senior...

Background The role of the measurements of postural stability in the context of screening for ankle sprain risk is still equivocal. Transient characteristics of body sway have been suggested as an alternative or an improvement to traditional whole-trial analyses. Research question Are transient characteristics of body sway sensitive to the history...

Background: Monitoring of physical activity within the educational institution is of great importance, primarily because of the orientation and content implemented in the daycare. This research aimed to examine the number of steps children took during their stay in daycare with regards to age, gender and the frequency of going out. Methods: The...

Children in schools are facing many academic challenges. Moreover, there is constant pressure on children and parents to maximize academic achievement. We aimed to determine the relationship between motor competence, physical fitness, and academic achievement in young school-aged children. Participants were 130 elementary school children (mean±SD8....

Regular exercise during school hours is encouraged since childhood obesity has reached epidemic proportions. Moreover, a great majority of adolescents do not meet the recommendations for moderate-to-vigorous physical activity. The present study aimed to determine the effects of school-based high-intensity interval training (HIIT) and nutrition inte...

This study investigated the effects of the Teaching Games for Understanding (TGfU) model implemented in physical education classes on volleyball skills and enjoyment in secondary school students. A total of 54 students (18 girls) from two classes participated in this study, of whom 28 (age = 15.5 ± 0.7 years) were randomized to a TGfU model (EXP) g...

The aim of this study was to determine and to compare the effects of different exercise programs on motor abilities in primary school children. A total of 60 (30 boys and 30 girls) primary school children, aged 12 years ± 6 months voluntarily participated in this study. Motor abilities were assessed by the following variables: the squat jump, long...

Functional movement is an important part of developing athletes' but also untrained individuals' performance. Its monitoring also proved useful in identifying functional limitations and asymmetries, and also in determining the intervention effects. The quasi-experimental pre-test post-test study investigated the effects of core stability training p...

This study was designed to compare the effectiveness of small-sided handball games in combination with handball training (SSG group) versus high-intensity interval training in combination with handball training (HIIT group) on physical performance of young female handball players during pre-competitive period. Twentyfour young female handball playe...

Swimming is a form of physical activity and a life-saving skill. However, only a few studies have identified swimming ability classifiers in preschool children. This pilot cross-sectional study aimed to find anthropometric (AM) and motor competence (MC) predictors of swimming ability in preschool children, by building classifiers of swimming abilit...

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)...

This study aimed to determine the effects of an after-school volleyball program on aggression and physical fitness in 14–16 years old students. One hundred and seven participants were randomized to a small-sided volleyball (SSV) training group or a control group (CON). The SSV group completed 8 months of small-sided volleyball training twice a week...