• Journal of Life Science
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• v.20 no.2
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• pp.314-320
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• 2010

As the nature of triathlons is competition in three successive sports, triathletes experience elevated levels of stress on the body that are absent in single-sport athletic events, and consequently there are more potential medical problems to prepare for. Triathletes can also experience problems such as hypothermia, heat illness, excessive exposure to ultraviolet radiation, musculoskeletal injuries and trauma, immunosuppression, and haemolysis. Depending on the potentiality of such above-listed problems occurring in any given race, race organizers will prepare preventative measures and treatments accordingly. Olympic distance is not the only triathlon racing distance. Sprints, which are normally around half the Olympic distance, are common distances, as well as Long (2 km swim, 80 km bike, 20 km run), Ironman (3.8 km swim, 180 km bike, 42 km run), and ultra-distance events varying in length. Races of longer duration normally result in a higher percentage of athletes experiencing the above-mentioned medical problems, as well as inducing additional health risks such as hyponatraemia. Minimizing the occurrences of serious health issues is possible through the following means: carefully preparing for the probable race-day weather conditions; proper management and organization of the race; preparing an extensive water-safety and ground-course safety plan; distributing necessary nutrition along the course; and stressing the importance for athletes to have proper knowledge concerning race nutrition, biomechanical technique, physical preparation, and utilization of safe equipment. While risks of competing in triathlon are many, the instances of such medical problems are not excessive, and the triathlon has a reputation of being a reasonably safe sport as long as athletes with high risk take added precautions.

• Journal of Life Science
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• v.25 no.11
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• pp.1324-1330
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• 2015

The present study was performed to analyze and review the physical and immune responses to overtraining syndrome in humans. Overreaching refers to the initial phage of overtraining syndrome and has been known as a physical fatigue which is mainly from metabolic imbalance. It has been known that overtraining also results in a loss of adaptability which may lead to an attenuation of exercise performance, sleeping disorder, central fatigue, neurohormonal changes, difficulty recovery to physical stress, and immunological changes. Additionally, overtraining syndrome is characterized by persistent fatigue, poor performance in sport due to the prolonged and strenuous physical training. Also, previous studies reported that endurance athletes experienced a high incidence of URTI during intense training and the post training. And also, high-performance athletes reported that suppression of cell mediated and anti-body mediated immune function. NK cell numbers were also reduced in the period of overtraining syndrome. Major components of prevention and treatment for the overtraining syndrome are screening, education, and detraining. Furthermore, the combination of these prevention and treatment strategies will be much helpful. Therefore, the current review will be helpful for athletes and individuals who are at the risk of overtraining syndrome.

• Journal of Industrial Convergence
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• v.22 no.4
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• pp.21-29
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• 2024

This study analyzed the difficulty of scoring in different match situations in relation to which competitor scored first. The study analyzed the data from the 2022 Guadalajara World Taekwondo Championships. The analysis was performed for two separate weight classes: lightweight and heavyweight. Four game content variables were used: whether the athlete scored first, attack type, attack area, and game situation. Descriptive statistics, the Rasch model, and discrimination function questions were applied for data processing. SPSS and Winsteps were used for the statistical analysis, and the statistical significance level was set at 0.05. Consequently, in the lightweight class, the scoring frequency of the first scorer was high for all the game variables. In the heavyweight class, the scoring frequency for the first scorer was high for the attack type and attack area. By contrast, those who did not score first were more frequently found to be in a loss situation. By analyzing the scoring difficulties in different match situations based on whether the competitor scored first, the athletes who scored first in attack type most easily scored first. In losing situations, the athletes who scored first in attack area scored most easily, whereas those who did not score first scored most easily in body and match situations. For the heavyweight class, those who scored first in terms of attack type, counter-attack, and attack area scored the most easily while winning in body and match situations.

• Korean Journal of Applied Biomechanics
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• v.21 no.2
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• pp.141-152
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• 2011

The purpose of this study was to investigate the projectile factors and biomechanical characteristics of men's hammer throwing during turning phases. Four national leveled athletes including Korea national record holder participated in this study. After full warm-up, each participant performed 6 trials of hammer throwing with their best. The best recorded trial was selected from each participant and they were analyzed for this study. Three-Dimensional motion analysis using a system of 5 video cameras at a sampling frequency 60Hz was performed for this study. As the number of turns increased, athletes revealed following characteristics. 1) The single and double support time decreased. 2) The rotation foot was closed to axis foot and it revealed greater medio-lateral displacement than that of horizontal one. 3) At the transition point from double support to single support, ball was in front of rotation foot so that not much angular velocity obtained. For the projectile factors, projectile angle did not show differences while projectile height and velocity revealed differences among the participants. It may indicated that each athlete has different fitness and skill level to resist centrifugal force which become larger as the number of turn increased.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.503-510
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• 2011

The purpose of this study was to find the biomechanical research project result carried out at 2011 IAAF World championship in Daegu. This project was approved by the International Amateur Athletic Federation(IAAF) and financially supported by the Ministry of Culture, Sports and Tourism(MCST) and, Korea Association of Athletics Federations(KAAF). The total number of the project members was 20, including the members of the Scientific Committee, the Korean Society of Sport Biomechanics(KSSB) and graduate students as assistants. The objective of this project has been to analyze the performance in the track events(100 m, 110 mH) and field events(Long Jump, High Jump, Triple Jump, Pole Vault, Javelin Throw and Shot Put). This project was focused on the biomechanical research only. This kind of analysis has been carried out at major competitions for more than a decade, as it provides coaches and athletes with very useful information as an aid to training programmes and competition preparation. The biomechanical analysis of the top athletes in the world in each specialty serves as a reference for assessing technique and rationalizing the results achieved. The results will be disseminated world-wide and coaches will be in a better position to design training strategies in line with current world trends.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.167-171
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• 2002

Purpose: To analyze the result of Modified Brostr$\ddot{O}$m procedure for Chronic ankle lateral instability without associated injury. Materials and Methods: Forty-one patients(Forty-one feet) diagnosed and operated with chronic ankle lateral instability without associated injury were evaluated retrospectively from June 1995 to December 1999. Twenty-three patients were athletes. For the evaluation of clinical outcome, a subjective grading scale of modified Hamilton was used, and pain relief, relief of instability symptom and anterior drawer test were evaluated. Results: Among forty-one operations, there were six excellent, thirty-five good results as a whole. All cases showed over the grade good. The average time to ordinary life in the non-atheletes was 2.5 months and average time to sport activity in the athletes was 4 months postoperatively. Conclusion: The modified Brostr$\ddot{O}$m procedure seems to be effective method for chronic ankle lateral instability without associated injury.

• Korean Journal of Exercise Nutrition
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• v.25 no.3
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• pp.8-15
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• 2021

[Purpose] Excessive reactive oxygen species (ROS) induced by prolonged high-intensity exercise can cause structural and functional damage. Antioxidant polyphenol supplementation, which reduces ROS levels, may improve high-intensity exercise performance. We evaluated the effect of lychee fruit extract, which contains high levels of low-molecular-weight oligomerized polyphenols, on high-intensity exercise performance. [Methods] Ten male athletes were included in an open-label trial that consisted of control and intervention phases, with a 7-day washout period between phases. The participants were administered oligomerized lychee fruit extract for seven days, whereas no intervention was given in the control phase. High-intensity intermittent exercise and the Wingate test were performed. The power output, blood lactate levels, reactive oxygen metabolite levels, biological antioxidant potential, heart rate, and rate of perceived exertion were measured. [Results] The average power output was significantly higher in the intervention phase than in the control phase (P < 0.01), while the change in blood lactate levels was significantly lower in the intervention phase than in the control phase (P < 0.05). The average heart rate was significantly higher in the intervention phase than in the control phase (P < 0.05), without changing the rate of perceived exertion. Although there was no difference in reactive oxygen metabolite levels between the phase, the change in biological antioxidant potential was larger in the intervention phase than in the control phase (P = 0.06). The Wingate test showed no significant differences between the phase. [Conclusion] Short-term loading with oligomerized lychee fruit extract may increase performance during high-intensity intermittent exercise by improving metabolism.

• Fashion & Textile Research Journal
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• v.19 no.3
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• pp.320-330
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• 2017

People have recently became interested in eco-friendly cycling that attracted further attention as a sport activity. The number of high school cyclists has increased due to the popularity of cycling; however, high school cyclists have trouble choosing cycling suits because there is no professional cycling suit for high school cyclists in Korea. Therefore, it is necessary to develop a professional cycling suit for high school cyclists because sportswear for athletes is an important means to improve performance. This study suggests a standard sizing system for high school student athletes' cycle tights. The subjects were 111 high school cyclists. The 3 clusters were categorized by cluster analysis, and the sizing system was classified according to three lower body types. The size intervals of waist girth, hip girth and height were 5cm, respectively. The most frequent sizes were 75-100-175 in figure type 1, 70-90-170 and 75-95-170 in figure type 2, 70-90-175 and 70-90-180 in figure type 3. The sizing system, which had frequencies more than 3.6%, was classified into 9 cases, 8 cases, and 5 cases, respectively by lower body types. The results will contribute to the development of athletic performance cycle wear for high school cyclists.

• Korean Journal of Applied Biomechanics
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• v.17 no.4
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• pp.209-219
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• 2007

The purpose of this study was to analyze biomechanical mechanism (posture, moment of back joint, EMG) when athletes (Judo, Ssirum) and lay people lifted a load according to two different lift methods; backlift and leglift. The number of subjects was 12; 8 athletes (4 for Judo, 4 for Ssirum) and 4 lay people. We recorded a lift motion in backlift and leglift using 7 real time infrared cameras (vicon) and analyzed EMG pattern of major muscles for a lift (lattisimus dorsi, erector spinae, biceps femoris). In a backlift Judo players showed a biggest range of back flexion and extension motion and lay people flexed more than other groups at phase 2 in which an interaction between groups and events was statistically significant (p=.024). In a leglift Ssirum players more flexed their back in a barbell lift and there was a statistical significance (p=.021) between groups and events. For moment of back joints, 1) in a backlift a larger loading on back joints in all three groups at phase 2 when lifting down a barbell, 2) in a leglift a larger loading on back joints when lifting down a barbell in two athlete groups but a larger loading when lifting up a barbell in lay people group, and all groups did not show any statistical significance. For EMG, right lattisimus dorsi muscle in a backlift was statistical significant (p=.006) in an interaction between groups and phase but left lattisimus dorsi muscle was insignicant, and there was not any significance in a leglift. Generally atheletes (Judo and Ssirum) used more their muscles of lower extremity in lifting up and down and lay people did more their ones of upper extremity.

• Korean Journal of Applied Biomechanics
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• v.30 no.2
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• pp.155-163
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• 2020

Objective: This study to identify the mechanism of head impact that occurs during youth soccer game with regard to head injuries in sports. Method: Ten male subjects (age: 10.0±2.0 yrs.) were participated during 10 soccer practices spread out over a time period of 10 weeks. During each soccer game, the participants agreed and wore the X-Patch (wireless accelerometer, gyroscopes). The X-Patch records the head impact mechanics, such as peak linear acceleration (PLA), peak rotational acceleration (PRA), peak rotational velocity (PRV), Head Injury Criterion (HIC), and the location of impact. Results: A total of 501 impacts to the head were measured over the 10 soccer games, PLA 17.8±10.4 g, PRA 3168±2442 rad/s²; PRV 16.1±10.6 rad/s; HIC 11.7±34.2. The severity of impact was classified into 3 ranges; low 10~39 g (482 impacts); medium 40~69 g (17 impacts); and high >69 g (2 impacts). There are no significant differences in PLA and HIC (p=0.08, p=0.15), however PRA and PRV show the differences (p<.05) between each of the participants. For the analysis comparing between the soccer games, there are no significant differences in PLA, PRA, PRV and HIC (p=0.11, p=0.13, p=0.14, p=0.05). Conclusion: Our results indicated that there were significant differences between athletes, especially in terms of rotational acceleration, whereas there were significant differences in linear and rotational based variable between each of the soccer games. Although the vast majority of impacts were below 39 g there were 2 potentially dangerous impacts above 69 g. It is important that future research continuous to measure head impact mechanics during soccer to help understand head injury mechanisms to ensure the safety of athletes.