Đorđe Hajder

Mr. Đorđe Hajder

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 March 2025 in Healthcare
Verified
Journal Article
Open access
PDF file
ĐHĐorđe Hajder
Đorđe Hajder
BBBojan Bjelica
Bojan Bjelica
Saša Radoslav BubanjSaša Radoslav Bubanj
Saša Radoslav Bubanj
Nikola AksovićNikola Aksović
Nikola Aksović
Milan MarkovicMilan Markovic
Milan Markovic
Mihai-Adrian SavaMihai-Adrian Sava
Mihai-Adrian Sava
(1) Background: The aim of this study was to conduct a systematic literature review and meta-analysis on the effects of virtual reality (VR) and traditional (TR) physical activity programs, analyzing their impact on the physical, health, and cognitive aspects of participants. The study sought to identify the advantages and limitations of both methods, taking into account previous research and potential areas for future studies. (2) Methods: The study protocol for this systematic review was registered at the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY202530015). The review followed PRISMA guidelines, and studies were selected based on their relevance to the research objectives using the PICOS model criteria. The authors applied a meta-analysis in addition to a systematic review to further ensure the accuracy of the results. Primary outcomes included physical and cognitive performance, while secondary outcomes encompassed participant perceptions and psychological effects. (3) Results: The findings indicate that VR training significantly enhances flexibility, motivation, and cognitive abilities, particularly in populations with limited access to traditional exercise methods. The most pronounced effects were observed in programs lasting 8 to 12 weeks with a moderate to high intensity. In contrast, TR showed superiority in developing strength, endurance, and cardiorespiratory functions. (4) Conclusions: VR offers significant benefits as an adjunct or alternative to TR, especially for individuals with limited resources or physical accessibility. However, variations in methodological approaches, short program durations, and sample heterogeneity highlight the need for further longitudinal research. Standardizing VR training duration and intensity is essential to ensure consistent and reliable outcomes.

4 March 2025
Verified
Report
Closed access
ĐHĐorđe Hajder
Đorđe Hajder
BBBojan Bjelica
Bojan Bjelica
Saša Radoslav BubanjSaša Radoslav Bubanj
Saša Radoslav Bubanj
Nikola AksovićNikola Aksović
Nikola Aksović
Milan MarkovicMilan Markovic
Milan Markovic
Mihai-Adrian SavaMihai-Adrian Sava
Mihai-Adrian Sava
INPLASY202530015 Comparing Virtual and Traditional Physical Activity Programs: Systematic Review Keywords: Effectiveness; Virtual Training; Digital Exercise; Online Fitness; Influence. Read and dow…

1 January 2025 in Physical Education and Sport Through the Centuries
Verified
Journal Article
Open access
PDF file
ĐHĐorđe Hajder
Đorđe Hajder
BBBojan Bjelica
Bojan Bjelica
Nikola AksovićNikola Aksović
Nikola Aksović
TDTatiana Dobrescu
Tatiana Dobrescu
Saša Radoslav BubanjSaša Radoslav Bubanj
Saša Radoslav Bubanj
The aim of this study was to compare the effects of resistance training on motor fitness and morphological characteristics of combat sports athletes - judokas and jiu-jitsu practitioners. The sample consisted of 40 participants (20 judokas and 20 jiu-jitsu athletes) who attended an eight-week experimental program with four training sessions per week. The resistance training program was performed at an intensity of 80% of each athlete's individual maximum capacity. Motor fitness was assessed using tests for squats, sit-ups, standing long jump, forward bend on a bench, and the 10×5 m shuttle run, while morphological variables included measurements of body mass, arm, thigh, chest, and waist circumference. The results showed statistically significant improvements (p < 0.05) in most motor fitness tests in both groups, indicating a positive impact of the resistance training program. Jiu-jitsu athletes achieved better results in trunk strength and flexibility tests (sit-ups and forward bend), whereas judokas were superior in explosive strength and speed tests (squat, standing long jump, and 10×5 m shuttle run). Although some changes in morphological parameters were recorded, the differences between groups were not statistically significant. These findings suggest that resistance training has a positive effect on the motor abilities of combat sports athletes, although specific adaptations depend on the nature of each sport. The results provide a basis for designing targeted training programs in accordance with the demands of individual combat disciplines.

1 January 2026
Verified
Conference Paper
Open access
PDF file
ZVZorana Veselinović
Zorana Veselinović
ĐHĐorđe Hajder
Đorđe Hajder
BBBojan Bjelica
Bojan Bjelica
RPRadomir Pržulj
Radomir Pržulj
Nikola AksovićNikola Aksović
Nikola Aksović
Saša Radoslav BubanjSaša Radoslav Bubanj
Saša Radoslav Bubanj
The aim of the study was to determine the effect of various corrective and preventive programs on scoliosis, one of the most common postural disorders in children and young people. Electronic databases such as PubMed, Web of Science, Scopus, MEDLINE, ERIC and Google Scholar were used in the literature review. Based on predefined criteria, ten studies that met quality standards were analyzed. The results of the study indicate that preventive programs that include specialized exercises, corrective gymnastics and individually tailored interventions significantly contribute to reducing the angle of spinal curvature and improving postural condition. It has also been shown that regular application of such programs has a positive effect on the functional abilities and psychophysical health of participants. Future research should focus on the long-term effects of preventive programs, including their application in different age groups and degrees of scoliosis. It is also recommended to examine the effectiveness of programs that combine corrective exercises with modern technological solutions, such as posture monitoring sensors and virtual reality. In addition, it is important to expand the samples to populations from different settings so that the results can be generalized and applied in a broader context.

4 August 2026 in SPORTS, MEDIA AND BUSINESS
Verified
Journal Article
Open access
PDF file
BBBojan Bjelica
Bojan Bjelica
ĐHĐorđe Hajder
Đorđe Hajder
MSMiroslav Smajić
Miroslav Smajić
MMMilan Milivojević
Milan Milivojević
Nikola AksovićNikola Aksović
Nikola Aksović
ASAldin Sarajčić
Aldin Sarajčić

1 January 2026
Verified
Conference Paper
Open access
PDF file
SKStevan Kovač
Stevan Kovač
BBBojan Bjelica
Bojan Bjelica
BCBorislav Cicović
Borislav Cicović
RPRadomir Pržulj
Radomir Pržulj
Nikola AksovićNikola Aksović
Nikola Aksović
Saša Radoslav BubanjSaša Radoslav Bubanj
Saša Radoslav Bubanj
Supplementation, as a modern approach to improving physical performance, has become an integral part of sports practice worldwide. Today, there are numerous nutritional supplements on the market that aim to increase muscle mass, reduce fatigue or optimize recovery. The aim of this study is to examine the impact of creatine on muscle strength and body composition parameters under specific training conditions. The research sample consisted of 19 recreational athletes divided into an experimental (n=12) and a control (n=7) group. The experimental group was supplemented with 5g of creatine monohydrate, while the control-placebo group received 5g of dextrose as a supplement. The experimental program was conducted for 8 weeks with a frequency of 4 training sessions per week. The effects of the experimental treatment on body composition (3 variables) and strength (3 tests) were monitored. Based on the results of the study, it can be concluded that the experimental treatment has positive effects on the strength of the subjects, an increase in muscle mass, while there were no statistically significant differences in the percentage of fat and body water. Fitness programs are an effective tool for improving the body composition and strength of women. It would be desirable to determine the effects of training on some other motor parameters and partial body parts when it comes to body composition.