The purpose of this study is to investigate the further direction of molecular biological studies, the advantages and limitations of assaying samples, and variables in figuring out the details of domestic and overseas studies verified through cell and molecular biological analysis in order to analyze the effect of concurrent training. The analysis study was limited to domestic and overseas literature, which investigated the effect of combined training using molecular biological analysis among studies to date. The study was reclassified by specialty, composed of professors of physical education and doctors of exercise physiology. The final selected study analyzed the subject and the trend of studies in terms of comprehensive perspectives. In detail, it analyzed hormonal and enzymatic changes in criteria such as leptin, 5-HT, ACTH(adrenocorticotropic hormone), cortisol, testosterone, GH(growth hormone), LDH(lactate dehydrogenase), CPK(creatine phosphokinase), antioxidants in blood samples and protein, and enzymatic and morphologic changes in for CRP, VEGF(vascular endothelial growth factor), PAI-1(plasminogen activator inhibitor-1), MAD(malondialdehyde), carnosin, and SDH(succinate dehydrogenase), the area of muscle fibers, ratio of type Ⅰ/Ⅱ muscle fiber and capillary proportion per muscle fiber in the extracted muscle by biopsy, for example. Finally, urine samples, and hormonal changes (like cortisol), were analyzed. The results of the analysis of domestic and overseas studies according to combined training has shown that this training has more varied effects than single training and lower improvement by interference effect or magnifying the effect of one type of training amongst the combined training types appears, rather than higher improvement through combined trainings. Therefore, it should be investigated in view of performance improvements relating to the characteristic of sports.
Purpose The purpose of this study was to provide useful information on the improvement of performance by measured the psychological-physiological stresses experienced by elite shooters during a competition. Methods Thirty-eight elite shooters participated in this study (Male = 13, Female = 25). Psychological stress was measured and used for this study based on the stress factors found in the elite target stress study by Park(2015). The cortisol, a physiological stress hormone, was measured using saliva. Results The reliability of the psychological stress sub-factor pre-post analysis results showed no statistically significant. The concentration of cortisol measured on the day before the competition (0.1704 µg/dL) significantly increased immediately before the competition (0.3558 µg/dL). Cortisol immediately before the competition showed negative correlation (r=-.361, p=.036) with the competition score, and the regression variable of cortisol was 13%. Conclusions In this study, physiological stress had a negative effect on elite shooters performance compared to psychological stress.
PURPOSE This study aims to provide empirical foundational data for the development of a new profit model in Korean professional baseball. It does so by examining the influence of professional baseball NFT product attributes on customer perceptions of value, satisfaction, and purchase intention. METHODS Data were collected from consumers who have experience purchasing KBOLLECT. A total of 363 samples were collected for analysis. Surveys were utilized for data collection, encompassing 39 items that measured product characteristics, perceived value, satisfaction, purchase intention, and demographic information. Using the collected data, various statistical analyses were conducted including descriptive statistics, exploratory factor analysis, reliability analysis, correlation analysis and multiple regression using SPSS version 21. The ensuing results from the correlation analysis and multiple regression analysis are as follows. RESULTS Product features, including aesthetics, symbolism, and scarcity, had a positive impact on consumer’s perceived emotional value. Moreover, product features, encompassing aesthetics, symbolism, scarcity, and creativity played a significant role in enhancing consumer’s perceived economic value. Furthermore, product attributes such as aesthetics, symbolism, and creativity positively contributed to consumer’s perceived social value. Similarly, product features comprising aesthetics, scarcity, creativity, and symbolism positively affected consumer’s perceived intellectual value. Additionally, the research revealed that product features related to aesthetics, symbolism, creativity, and scarcity were instrumental in bolstering consumer. Importantly, these very attributes, including aesthetics, symbolism, scarcity, and creativity, exhibited a positive influence on consumers’ purchase intentions. CONCLUSIONS In conclusion, this study underscores the substantial impact of professional baseball NFT product characteristics on consumers’ perceptions, satisfaction, and purchase intentions. To maintain enduring relationships with consumers who engage with professional baseball NFT products, it is essential to fortify these product attributes and offer diverse services utilizing them.
PURPOSE This study was conducted to estimate the tendency of psychological factors influencing cycling performance by analyzing the characteristic factors of athlete reputation in the news big-data. METHODS To explore the psychological factors influencing cycling performance, an open questionnaire was conducted on 82 cyclists, and Inductive Content Analyses was performed. Overall, 89,520 news articles were collected through BIGKinds, and forming factors of athlete reputation were derived through LDA topic modeling analysis and inductive categorization. Through regression analysis, time series tendency of the factors of athlete reputation was calculated. Finally, the tendency of psychological factors to influence cycling performance was estimated based on the previously derived results in this study. RESULTS The psychological factors influencing cycling performance were found to be; emotion control, trust capital, cognitive control, motivation and communications with the coach. The forming factors of athlete reputation was found to be; reporting of the sports event, infrastructure creation, analysis to performance, moral issue, social environmental changes and sports gossip. The time series tendency of the forming factors of athlete reputation was found to include the categories of Hot, Warm, Cool and Cold. The psychological factors influencing cycling performance are estimated to expand to exercise performance and moral intelligence. CONCLUSIONS The results of this study suggest that the discussion of psychological factors influencing cycling performance extends not only to exercise performance, but also to moral intelligence, reflecting the socio-cultural context in the discussion of performance.
PURPOSE The purpose of this study was to establish the criteria for measuring acute muscle fatigue using tensiomyography (TMG) by quantifying the trend of changes in TMG variables. METHODS Searches were conducted in the Web of Science and Pubmed databases using the keyword “Tensiomyography”. Sixteen studies which used TMG to measure acute muscle fatigue caused by acute exercises in rectus femoris or biceps femoris were included. All statistical data analyses were performed using Comprehensive Meta-Analysis software program. RESULTS The meta-analysis results indicated that the biceps femoris showed a significant (p<.05) decrease in all TMG variables of the elite athletes. Also, in the overall effects of maximum displacement and mean velocity until 90% Dm (Vc90) showed a significant (p<.05) decreasing trend. The rectus femoris showed a significant (p<.05) decreasing trend for maximum displacement (Dm) in the average person, while contraction time (Tc) showed a decreasing trend in elite athletes and overall. CONCLUSIONS These results suggest that TMG could be used as an indicator of muscle fatigue indicator, and will help to develop a more proper protocol to test the response of the body to muscle fatigue.
[Purpose] The purpose of this study was to predict winning percentage in the Korean Basketball League(KBL) by applying the possession concept. [Methods] The model to estimate possession was utilized by formula used in NBA(National Basketball Association). Data consist of 20 seasons of the KBL (1997-2017). For data analysis, multiple regression analysis, Fisher’s Z transformation and stepwise multiple regression analysis were performed using SPSS 22.0. [Results] The result indicated that average team stats per possession had more explanatory power in predicting the KBL teams’ winning percentage than average team stats per game. The most important factor for winning in the KBL was defensive rebounds and followed by 2-point field goal percentage, steals, 3-point field goal percentage, free throw attempts, turnovers, offensive rebounds, blocked shots, free throw percentage, and assists. The results of this study provided fundamental information for the data analysis of Korean basketball games. It might be useful for basketball coaches to manage and instruct their teams. [Conclusion] Practical implications and future research direction were also suggested.
The purpose of this research is to investigate the factors affecting the performance capability of lunge movements by performing lunge movements which are commonly used as a method of instant physical movement in sports with a kinetic analysis including an EMG analysis. This research targeted 14 skilled fencers and made the subjects perform kick-lunges which allow them to go farthest from their positions and performed an analysis on such, applying a 3D motion analysis system and an EMG system. The subjects performed kick-lunges in two movements; one with a preliminary movement and the other without it and those are performed with both dominant leg and non-dominant leg. The result of this research is as follows. The lunges with a preliminary movement showed higher performance capability than those without it. Furthermore, as the level of skills gets higher, the length of lunges gets longer, and it seemed that a tactical mechanism shortening exercise performance times was used as a mechanism to control the impulse coming from such lengthened lunges. In addition, a difference appeared in mechanical factors such as moment and power in a dominant leg movement and it seemed to result from a difference in an functional capability using muscles.
PURPOSE The purpose of this study was to provide information for improving the performance and skills of 500 m speed skaters by analyzing the kinematic and kinetic changes in their slide board movements over time. METHODS The subjects were 10 male short-distance skaters in their 20s to 30s who were registered as professional athletes with the Korea Sports Council. The changes in joint angle, joint moment, and joint power over time in the subjects’ slide board motion were measured and analyzed. RESULTS It was found that during phase 2 of the skater’s slide board movement, there was an increase in plantar flexion and a decrease in flexion of the lower extremity joint and extension of the knee and hip joint, with decrease in positive power of the knee joint. CONCLUSIONS The results of this study are expected to provide practical information to skating coaches and athletes by quantifying the biomechanical factors observed over time during slide board movements. In addition, this study is expected to contribute to the field of speed skating by presenting scientific training methods and proposing new analysis techniques to improve performance in the future.
PURPOSE This study comprehensively examined the aerodynamic and flight characteristics of modern soccer balls, focusing on their design evolution and performance attributes. METHODS The aerodynamic characteristics of five types of World Cup balls (2006 Germany World Cup, 2010 South Africa World Cup, 2014 Brazil World Cup, 2018 Russia World Cup, 2022 Qatar World Cup) and five types of Euro tournament balls (EURO2008, EURO2012, EURO2016, EURO2020, EURO2024) were examined, along with their respective design changes. RESULTS Through detailed analysis, significant variations in aerodynamic properties among soccer balls used in various tournaments were identified. Recent advancements have resulted in faster transitions towards critical Reynolds numbers, indicating improved stability in flight trajectories. This enhancement was attributed to the augmentation of surface roughness, which plays a crucial role in enhancing aerodynamic stability and overall performance. 2D simulations simulating powerful goalkeeper kicks revealed distinct differences in flight distances among different soccer balls; the Jabulani ball used in the 2010 World Cup exhibited the longest flight distance, while that of the 2024 Euro ball was the shortest. CONCLUSIONS Variations in surface texture significantly impact aerodynamic properties, affecting flight distance, arrival time, and height. This study underscores the significant design enhancements in modern soccer balls that optimize aerodynamic stability and performance, with modifications aimed at improving flight characteristics and enriching player experience.
PURPOSE This study aimed to provide evidence for improving the working environment by exploring the phenomenon of presenteeism experienced by coaches. METHODS Ten coaches experiencing presenteeism were selected as participants of the study using the snowball sampling method, and in-depth interviews were conducted. The in-depth interviews were conducted for about 50 to 60 min using semi-structured questions organized through pre-expert meetings, and inductive content analysis was conducted. RESULTS First, the health problems that developed while coaching were categorized into two detailed areas (physical and psychological symptoms). Second, the causes of presenteeism were categorized into four general areas (policy and institutional problems, poor job environment, athlete problems, and human relations). Third, performance loss due to presenteeism was categorized into two general areas (coach-athlete relationship damage and poor training performance). Finally, coping with presenteeism was categorized into three detailed areas (private time spending, joining acquaintances, and changing training methods). CONCLUSIONS The result of this study confirmed that coaches are currently experiencing the phenomenon of presenteeism for various reasons, and the symptoms and coping method for this differ with each individual. However, the phenomenon of presenteeism experienced by coaches requires further future research since it is not easily observed and the coping method is not efficient.
