PURPOSE The purpose of this study was to investigate the risk factors for anterior cruciate ligament injury using the Landing Error Scoring System (LESS) and muscle activity during the drop vertical jump for overweight females. METHODS The body mass index was 18.5-22.9 kg/㎡ for normal weight females and 23-24.9 kg/㎡ for overweight females among 10 participants aged 20-30 years classified into groups of participants without any injury history and those who were right-footed. An automatic heigh-tweight machine, body composition analyzer, diagnostic imaging, electromyography with the LESS, and muscle activity analysis were used for measurements. The difference in muscle activity between the normal weight and overweight females was evaluated by independent t-test. RESULTS Overweight females had a smaller angle of knee bending during the drop vertical landing, leading to a smaller knee curve angle. In addition, they landed with an unbalanced foot touch on the ground inclined backward, thereby breaking the whole body balance. Overweight females had an incorrect posture compared with normal weight females, with higher LESS points. The muscle activity of the rectus femoris was higher than that of the biceps femoris, indicating a higher load on the muscle. CONCLUSIONS Overweight females take more load on the knee joint and cannot absorb the impact force properly. These results suggest a higher risk of anterior cruciate ligament injury in overweight females.
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.
PURPOSE This study aimed to present isokinetic quadriceps and hamstring muscle strength values in K league 1 (K1) professional soccer players and compare these results to those of published studies. METHODS A total of 31 K1 soccer players (age 24.5±4.2) without a history of lower limb injury were included in this study. Isokinetic knee strength tests were implemented at a velocity of 60°·s-1 and 180°·s-1 for both dominant (D) and non-dominant (ND) legs using a dynamometer. Strength variables included peak torque (PT), body mass normalized PT (NPT), bilateral strength difference (BD), and hamstring to quadriceps strength (H/Q) ratio. RESULTS At 60°·s-1 velocity, the NPTs of the quadriceps were 3.39N·m·kg-1 and 3.33N·m·kg-1 for D and ND legs, respectively, and those of the hamstrings were 2.00N·m·kg-1 and 1.89N·m·kg-1 for D and ND legs, respectively. At 180°·s-1 velocity, the NPTs of the quadriceps were 2.31N·m·kg-1, 2.27N·m·kg-1 for D and ND legs, respectively, and those of the hamstrings were 1.42N·m·kg-1, 1.39N·m·kg-1 for D and ND legs, respectively. At all velocities, the BDs of quadriceps and hamstring muscles ranged from 6.6–7.8%, and H/Qs ranged from 57–62%. Compared to previous studies that did not consider the history of injury, this study showed lower levels of BD (less than 10%) and higher levels of NPT. CONCLUSIONS The presented isokinetic quadriceps and hamstring muscle strength values can be used as reference values for the isokinetic knee strength of K1 professional soccer players.
PURPOSE This study aimed to investigate the effects of COVID-19 on elite youth athletes by investigating their activities and eating habits before and after the COVID-19 pandemic. METHODS This study included 917 elite adult athletes from 19 sports and were grouped into 6. The questionnaire included items regarding demographics, physical activity, sleep, and eating habits before and after COVID-19. A total of 44 questions requiring subjective short answers were included. Statistical significance was set at p< 0.05. RESULTS After COVID-19, vigorous and moderate activity decreased across all sports; however, light activity increased in almost sports. Time spent sitting increased across all sports. The difference in the number of meals consumed varied among sports, and the number of competitions decreased in all sports. CONCLUSIONS The COVID-19 pandemic appears to be finished but has not ended yet. Athletes must determine the best way to maintain their physical, physiological, and psychological states close to their original abilities. Determining this will provide the greatest impact on the return of athletes after COVID-19; this study will be helpful.
PURPOSE This study was designed to propose a quantitative base training evaluation method through alpine ski training monitoring using a triaxial accelerometer. METHODS Twelve Korean alpine ski athletes, six each in France and New Zealand, participated in this study. Activity data during training and daily living were collected for 7 days via the Actigraph GT9X. The collected data were downloaded through ActiLife Ver 6.13.1. Energy expenditure was calculated with Freedson (2011), and the resting metabolic rate was corrected using the Harris & Benedict (1918) formula. Further, the physical activity intensity classification criteria and METs formula of Freedson (1998) were used to classify hourly activity intensity. The collected data were organized by date, time, intensity, and energy expenditure using Microsoft Excel 2016. Differences between weekdays vs. weekends and skiing vs. physical training were analyzed through a paired sample t-test using Windows SPSS 23 with a significance level of a=.05. RESULTS First, both groups showed repetitive on and off high-intensity activities during scheduled ski training and competition. Second, moderate-intensity activities accounted for an average of 6-10%, and the weekly total time and intensity of MVPA was very high. Finally, the group from France showed differences in total energy expenditure during weekdays vs. weekends (p<.05) and the energy expenditure of both ski training and physical training during weekdays vs. weekends (p<.05). The New Zealand group showed a difference in total energy consumption during weekdays vs. weekends (p<.05). CONCLUSIONS A systematic training program based on quantitative training evaluation should be developed for alpine ski athletes to maintain proper rest and exercise intensity levels.
PURPOSE This study aimed to develop a model for life skills transfer in sport. METHODS A literature review of research on life skills transfer was conducted. The prior representative studies on sport life skills and transfer models were selected and discussed to improve the validity of this study. RESULTS First, based on the basic psychological needs of the internalization and generalization of life skills, the model for life skills transfer should consider the influence of the explicit and implicit climate and environment. Furthermore, access to cognitive processes is required based on the conceptualization and integration of transfer. Second, the concept of a transfer was defined, and key issues of the cognitive processes that support the connection between the sport domain and out of the sport domain were discussed. Third, the model for life skills transfer in sport was presented. In this model, life skills transfer occur through sport context, cognitive process, promoting factors, and out of sport context. CONCLUSIONS Since the 2000s, research on life skills and transfer in sport has developed quantitatively based on positive youth development theory. Unfortunately, research on this area in South Korea is very insufficient. This study suggests a model for life skills transfer in sport based on an extensive and systematic analysis of the prior research, and this model can be used for future research.
PURPOSE This study aims to show that the ground for moral condemnation for an act, including cheating, is too vague and ambiguous in sports. Further, in sports, such condemnation and moral assessment must be found in ethical conventions within sports communities. METHODS I discuss how to distinguish between acceptable and unacceptable conduct in sports—what exactly is a moral action in sports, and on what basis moral condemnation or praise can be imposed on an action. These are discussed to understand the complexity and ambiguity of sports norms. Next, by examining the concept of cheating offered by prominent moral philosophers and sports philosophers, I argue that the concept of cheating does not have a useful moral compass for identifying cheating in sports. Finally, I show that the practical reasons used by sports communities to justify the normative qualification of actions in a specific way cannot be separated from the practical reasons produced by sports practices. RESULTS I argue that, since cheating in sports does not have the status or qualification of a concept, the evaluation of ethical behavior in sports should be based on the conventional norms instituted within the realm of sport as its starting point and moral basis. CONCLUSIONS Therefore, the normative evaluation of whether an action in sports has been ethically justified should be undertaken from a conventional evaluative perspective operating within the sports community rather than relying on a philosophical verification based on independent reason outside sports.
PURPOSE This study compared and analyzed the current status, system, and trend of evaluation and operation of member sports organizations of the Korean Sport & Olympic Committee from 2006 to 2020. METHODS A literature study was conducted for this study. RESULTS The 15-year evaluation was developed through three periods: preparation, execution, and construction. The preparation stage (2006–2009) was when the evaluation index development and operation system were established. The execution stage (2010–2016) is a critical time; when the current system was established. This was when evaluation perception was spread in the sports world and continuous changes such as evaluation system and operation, indicators. Finally, the construction stage (2017–2020) was when the evaluation system was established after integrating the Korean Sport & Olympic Committee and the National Sports Council. CONCLUSIONS It played a role in promoting balanced growth from organizational management to ethical management of sports organizations through preparation, execution, and construction. Further, the evaluation reflected the continuous development and change of the Korean sports community and one organizational assessment.
PURPOSE This study examined the process and cause of change in nationalism in German gymnastics in the 19th century. METHODS The study used a literature study method and analyzed data from previous studies. Eleven articles related to the research topic were chosen for domestic research data by searching RISS for "German gymnastics," "Turnen," and "German nationalism." Overseas research data involved seven articles related to this study and were found by searching for "German gymnastics" and "Turnen" in Google Scholar. RESULTS First, German nationalism was originally divided into liberal nationalism and nationalistic nationalism, resulting in nationalistic nationalism after German reunification. Second, Jahn as a liberal nationalist and Spiess as a nationalist attempted to spread their ideas through German gymnastics. Finally, German gymnastics change from Jahn's liberal nationalism to Spiess' nationalistic nationalism was inevitable due to German gymnastics' external background and inherent limitations. CONCLUSIONS This study illustrated the process and cause of the change in the nationalistic characteristics of German gymnastics in the 19th century. Various historical cases that have not yet received attention but are worthy of investigation must be studied.
PURPOSE This study aims to analyze research trends on the social capital in sports. METHODS A total of 69 papers published until December 2020 were selected as research subjects. Further, Excel, KrKwic software, and NetDraw function of the UCINET 6 program were used for analysis. RESULTS First, social capital research on sports has shown quantitative growth since 2010. Second, the studies were conducted on sports participants such as general, elderly, college students, adolescents, foreigners, and the disabled, showing the highest frequency of research subjects. Third, quantitative research conducted based on the research method were several. Fourth, single-author studies were the highest. Fifth, as the result of the analysis on the publication journal, the Journal of the Korean Physical Education Association was shown the highest. Sixth, due to frequency analysis of the thesis keywords, “social capital,” “sports participation,” “action intention,” “social capital type,” “living sports participation,” and “youth” were shown the highest. Seventh, as a result of centrality analysis between keywords through the network analysis, “sports participation” in connection centrality, “health-promoting lifestyle” in proximity centrality, and “sports participation” in mediation centrality were found as the highest. CONCLUSIONS The significance of social capital in sports is more important than others because it is a fundamental element for creating a culture where more people can enjoy sports moderately in Korea, where capitalism and liberal democracy were adopted as the governing system. Therefore, this study can be a vital resource significantly contributing to the understanding and active use of social capital, a significant factor in developing sports in Korea.
