PURPOSE This study aimed to verify the accuracy of three-dimensional (3D) motion data produced through artificial intelligence-based user motion recognition technology with images obtained using a smartphone monocular camera. This was done to explore the possibility of developing an application that can improve the reliability of the measurement of physical activity performing motions and feedback provision. METHODS To check the accuracy of the artificial intelligence-based 3D motion analysis system that utilized a semi-supervised learning method, a commercialized 3D infrared motion analysis system measured and compared motions on three movement planes, motions with limited joint movement, and fast motions in a wide moving range. RESULTS The motions on the coronal and sagittal planes produced through the 3D motion analysis application showed very high measurement accuracy; however, the accuracy of the measurement of motions on the horizontal plane, which could not be measured directly with a camera, was relatively lower than that of the coronal and sagittal planes. Accuracy in measuring 3D motion was moderate in moving motions and low in motions with limited joint movement. CONCLUSIONS For the developed 3D motion analysis system to be used in online physical education, the types of physical activities included in the program should be comprehensively composed through the analysis of the content system of the physical education curriculum and the resultant physical activities.
The purpose of this study was to analysis of moving distance during games, time and heart rate for hockey games using GPS (global positioning systems) by positions in Korea national female athletes. The subjects were Korea national female hockey players (n=13) including 4 forwards, 4 midfields, and 5 fullbacks that participated in five Korea vs. Japan international games. All subjects were wearing GPS throughout the games. The results were as follows: Firstly, the average total travel distance per game was approximately 5.7km and higher in the second half. Physical movement in the games was not different from positions where 70% of physical movement was performed at low intensity and 30% at moderate and/or vigorous intensity, suggesting that the subjects; physical movement was performed at the appropriate level of exercise intensity. Secondly, during the game, the subjects performed physical movement faster than 11km/h for 22 minutes, indicating that the subjects could maintain their physical movement at a relatively faster speed throughout the games. In particular, midfields showed a greater amount of physical movement at moderate speed. Thirdly, the average exercise heart rate was 145bpm, which was equivalent to 60% of HRmax. The subjects maintained their average exercise heart rate greater than 150bpm (above 60% of HRmax) for 40 minutes during the games, indicating that the players had an ability to maintain physical movement at high intensity throughout the games. In conclusion, in spite of the fact that Korea national female hockey players have an ability to maintain physical movement at a relatively faster speed and higher intensity, their physical movement and performance are often affected. Therefore, it is necessary to develop and apply the specific interval training program for national female hockey players that can facilitate the faster recovery from the repetitive physical movement requiring power and speed at high intensity.
Purpose This study was aimed at interpreting the football talent development stages based on complexity theory. Methods The data for this study was gathered through literature review and in-depth interviews that were analyzed by thematic analysis. Literature review of the studies regarding complexity theory revealed the features of complexity theory and five football players participating in the K-league were interviewed. Gathered materials were analyzed by the thematic analysis. Initial codes and potential themes of football talent development stages, the conception and potential themes of the complexity theory were interpreted by metaphorical analysis. Results Results of literature review were as follows: analysis frame of complexity theory were organized environment of complexity, feedback structure, self-organization, critical condition and emergent phenomenon. The football talent development stages, interpreted as a result of literature review, were divided into Potential Talents, Excellence based Talents Development, Footballizational Talents, Football to Takeoff and Personalization of Football Talents. The stages were specifically materialized as follows: Potential Talents was materialized into physical condition, physical activity preference and change of environment. Excellence based Talent Development was materialized into skill mastery, thoughts about football and relationship with significant others. Footballizational Talents was materilized into skill fractionation, football flow and growth experience. Football to Takeoff was materialized into overcoming crisis experience, performance scaffolding and performance takeoff. Personalization of Football Talents was materialized into manifestation of performance personalization, performance evolution, condition maintenance. Conclusion Football talent development stages, interpreted by means of complexity theory, were divided into Potential Talents stage, Excellence based Talent Development stage, Footballizational Talents stage, Football to Takeoff stage and Personalization of Football Talents stage. Utilization of this study as a fundamental resource of football talents development programs and as a means to understanding football talents development is looked forward to.
PURPOSE This study aimed to develop and implement a customized mental plan program to facilitate an optimal psychological state and peak performance among para shooting athletes. It also sought to empirically verify this program’s psychological effects by focusing on improvements in concentration, confidence, and relaxation. METHODS A total of six para shooting athletes who had earned medals in the Paralympic Games underwent six program sessions that were designed and implemented based on attention-related psychological factors identified through open-ended surveys and in-depth interviews. RESULTS The athletes’ attention was facilitated by task-focused behavior, breathing control, performance routines, and physical condition management. Meanwhile, their concentration was hindered by task-irrelevant thoughts, negative physical states, and external distractions. These factors were further categorized according to competition phase: the day before, precompetition, and during competition. Based on the statistical analysis, significant improvements were observed in the athletes’ concentration, confidence, and relaxation. CONCLUSIONS The custom program was practically effective as an intervention for psychological skills tailored to experienced para shooting athletes’ individual needs. The findings offer valuable insights for developing strategies supporting the psychological states of athletes in disabled sports.
This study aims to suggest the guide line for weight category sports(Taekwondo, Judo, Wrestling, Weightlifting, and Boxing) who have to lose weight to pass weigh-in before games. Reference data was collected from RISS, Medline, PubMed, SciELO and effects of short term weight loss on physiological variables(body composition, physical fitness, blood components, oxidative stress and hormone, immune function) were analyzed. Also, weight loss procedures for weight category sports athletes were analyzed in details. The results of the research are as follows: weight category sports athletes prefer short term (3~5 days) weight loss methods (3~5%) with dietary control, sweating and exercise. Physical changes caused by the loss in body weight, fat-free mass, and BMI, however, do not affect body fat percentage. Different changes of physical strength element depend on weight reduction period. In short term weight loss method, anaerobic exercise capacity, muscular strength, and reaction time partially decrease and affect staying power. In contrast, long term weight loss method do not affect aerobic and anaerobic exercise capacity. Furthermore, most of previous studies show that blood component change has negative effect on body water balance, stress-related hormone, and immune function. In conclusion, short term weight loss method negatively affects athletic performance of weight class competition athletic. Therefore, careful long term weight loss methods are recommended with dietetic consideration to prevent dehydration during weight loss period. Excessive weight loss on lightweight athlete should be prevented by institutional basis as well.
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.
The purpose of this study was to provide managers and owners of Korea professional baseball teams with the necessary information for improving managerial performance by fan acquisition and retention. This paper chose LG, Nexen, and SK fans over the age of 17 as population of this study who visited at least twice home games held in the Jamsil, Mokdong, and Munhak baseball stadium. For the analysis of data, 413 questionnaires were used using SPSS 15.0 Windows and Amos 7.0. To examine respondents demographics traits, frequency analysis was processed and reliability analysis, confirmatory factor analysis and correlation analysis for relationship among the variables were conducted. Also, convergent validity analysis and discriminant validity analysis were made. Finally, path analysis was made for the verification of model suitability and of research hypotheses through structure equation modeling. The research results are as per the below. First, team attributes like physical facilities, team performance and licensing had significantly positive influence on consumption emotion. Second, team attributes like service and team performance significantly positive impact on viewing value. Third, consumption emotion had significantly positive impact on revisit intention. Fourth, viewing value had significantly positive impact on revisit intention.
This study was purposed to explore psychological change and regulation process during badminton competition. The data were conducted using group interviews and participation observations who 18 K college badminton players. The data were analyzed using open, axial, and selective coding based on grounded theory method (Strauss & Corbin, 1998). The results were as follows: Open coding results, 89 concepts, 44 subcategories, and 18 categories emerged as psychological change and regulation process during badminton competitions. Axial coding results, the categories are showed structural relationships such as performance, score, psychological momentum, the importance of competition, court environment, physical condition, competition strategy, psychological preparation, past experience, outcome expectation, psychological disturbance, psychological skills, game situation-changing strategy, support-seeking strategy, significant others' behavior, the opponents' behavior, psychological resilience, and maintenance psychological disturbance. Selective coding results, core category of this study was revealed to maintain psychological homeostasis. Environmental context during badminton competitions causes specific situations and events that evoke psychological disturbance. In turn, a player seeks mental and behavioral strategies to maintain psychological homeostasis. There is psychological homeostasis mechanism during badminton competitions for peak performance. Development of proper interest for psychological homeostasis will be improved through this research approach in sport psychology.
Purpose The valuable impacts of exercise-intervention in diverse type of cancer patients were rationally well-prescribed, though many experimental and review researches already performed in this fields. Generally, cancer-related fatigue and pain remains one of the most prevalent problems for cancer populations. Therefore, exercise has become increasingly significant in cancer prevention and progression. The purpose of this recent study was to analyze the combined exercise program on cancer-related fatigue, pain, quality of life and cancer prognosis in diverse type of cancer patients. This study analyses the safety and feasibility of exercise intervention in diverse stages of cancer patients such as early stage, advanced stage and even metastatic periods in cancer populations. we also wanted to know the impacts of dose-response trial of aerobic and resistance exercise on quality of life in cancer survivors. Methods we conducted a comprehensive PubMed/MEDILINE electronic database from Jan 2015 to August 2020. The reference lists of eligible experimental research articles and relevant systemic review articles were checked. Inclusion criteria were adult cancer survivors from randomized controlled trials performing well-tailored exercise intervention programs to diverse type of cancer patients, Using predefined search items ‘exercise-intervention, cancer & immunology’. Based on reference search, more than 100 articles were identified whereas 30 research papers met the inclusion criteria and were well connected with exercise-intervention and cancer progression. we analyzed the connections between physical exercise and cancer intervention in the main text. Results Moderate to vigorous exercise (aerobic and resistance exercise) revealed to decreased level of cancer-related fatigue, pain, and cancer-related symptoms, however increased level of sleep quality, activities of daily living, exercise performance and health- related quality of life. Exercise intervention reduced pro-inflammatory markers and oxidative stress as well as insomnia, fatigue, pain symptoms whereas it enhanced the antioxidant systems and immune functions. In addition, home-based aerobic physical exercise might enhance muscular strength and quality of life in many types of cancer survivors. Psychological intervention also effective for reducing cancer-related fatigue and pain during and after cancer treatment. they might be the much better intervention than available pharmaceutical options. we believe that it is the related mechanisms of immune cell mobilization and activation such as NK cells which is induced by the activation of sympathetic system during and after physical exercise. Conclusion According to the aforementioned results, it was concluded that implementation of exercise intervention appear to be the best non-pharmaceutical interventions for cancer populations, and also revealed to be safe and feasible in early and advanced stages, although not in the metastatic periods. Sometimes, psychological intervention such as mindfulness-based stress reduction (MBSR) might be useful in reducing anxiety, depression, fatigue, pain and enhancing quality of life, quality of sleep for cancer populations. we can conclude, exercise-intervention might not just be prevention effect but might be therapeutics, however more studies are urgently needed to confirm the exercise intervention on the NK-receptors activation and immune connection of cancer populations.
PURPOSE The purpose of this study was to investigate the effects of 8-week aerobic exercise and polyphenol intake on body composition, cardiovascular response, vascular endothelial function, and physical fitness at rest and during exercise in prehypertensive men. METHODS The study included twenty-eight males in their 20-30 years of age with prehypertension. Participants in the aerobic exercise + polyphenol intake group (EX + PP; n = 14) performed aerobic exercise three sessions/week, 30 min/session, at 65% of the heart rate reserve, and consumed polyphenol (grape seed extract 300 mg) for 8 weeks. Participants in the aerobic exercise + placebo intake group (EX + PL; n = 14) performed the same aerobic exercise; however, they consumed placebo instead of polyphenol. All independent variables were measured at pre-test and post-test, and the data were analyzed. RESULTS The main results of the study were as follows: 1) SBP and MAP at rest decreased significantly in EX + PP, while MAP decreased significantly in EX + PL group. 2) In the EX + PP group, CO increased significantly, whereas DBP, MAP, and TPR decreased significantly during the hand grip exercise. In contrast, CO decreased significantly, while DBP and TPR increased significantly in the EX + PL group during the hand grip exercise. 3) Regarding vascular endothelial function, % FMD increased significantly in EX + PP group. 4) Sit-up increased significantly in both EX + PP and EX + PL groups; however, sit-and-reach in EX + PP group was significantly higher than that in EX + PL group at post-test. CONCLUSIONS The findings of this study showed that the 8-week aerobic exercise would have positive effects on body composition, cardiovascular response, and physical fitness at rest and during exercise in hypertensive men. Additionally, polyphenol intake would contribute more towards reduction of blood pressure at rest and during exercise and improvement of vascular endothelial function.
