• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.1-9
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• 2014

The purpose of this study was to investigate the muscle mechanical properties of the pelvic axial pre-rotational movement for the Jireugi in the Taekwondo Juchumseogi stance. Eleven elite Taekwondo Poomsae athletes participated. Each participant performed 5 right hand Jireugi in Juchumseogi stance as fast and strong as possible while their motion was recorded by a 3D motion analysis system and the ground reaction forces by two force plates. The power and work of the muscular group surrounding the waist were analyzed to verify the effect of the stretch-shortening cycle (SSC) theory. The cause of the greater power seems to be the application of the SSC by the muscles surrounding the waist during the preparation phase of the pre-rotation group. For the none pre-rotation group, they only used the concentric contraction of the muscles surrounding the waist. Because the pre-rotation group used the SSC theory, they had the effect of shortening of the range of movement, creating a fast and more powerful rotation, thus anticipating the increase the magnitude of impact.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.4
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• pp.85-93
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• 2021

PURPOSE: This study aimed to examine the evaluation of muscle activity, muscle fatigue and balance in male high school Taekwondo athlete with a deformity of the medial longitudinal arch. METHODS: The 20 male high school Taekwondo athletes participated in the study they have been measured radiographic a medial longitudinal arch and divided into a medial longitudinal arch group (higher than 18.8°; MLA group, n = 12) and control group (lower than 18.8°; CON group, n = 8). All subjects were measured muscle activity (TA, PT, PL and PB), muscle fatigue (TA, PT, PL and PB) and balance (A-, AL-, L-, PL-, P-, PM-, M-, AM-direction and composite score; CS). RESULTS: The muscle activity of TP was significantly higher in MLA group compared to CON group (p = 031) and the muscle fatigue of TA was significantly lower in MLA group compared to CON group (p = .043). However, balance did not show significant differences between the groups. CONCLUSION: These results confirmed that male high school Taekwondo athlete with a deformity of medial longitudinal arch increase TP and decrease TA, but there was no difference on balance.

• Journal of muscle and joint health
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• v.29 no.2
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• pp.133-140
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• 2022

Purpose: This study was to examine the effects of auricular acupressure on competitive state anxiety and the accuracy of breaking in taekwondo players. Methods: This study was a quasi-experimental study with a time-series design. Twenty-two taekwondo breaking players were assigned to the control group for the first two weeks and then assigned to the experimental group for the next two weeks. Anxiety was measured by the revised Competitive State Anxiety Inventory-2 and the accuracy of breaking was measured as a percentage of breaking the wooden board. Results: Auricular acupressure for two weeks significantly increased the accuracy of breaking from 80.83±7.99% to 90.92±7.57% (t=7.74, p<.001). Auricular acupressure for two weeks significantly increased anxiety from 35.66±10.36 to 50.64±7.45 (t=4.38, p<.001). Among three subtypes of competitive state anxiety, somatic anxiety was increased from 12.48±4.97 to 22.95±4.54 (t=2.09, p=.011). Cognitive anxiety was significantly increased from 10.11±3.96 to 14.68±3.89 (t=5.37, p<.001) but self-confidence was not changed. Conclusion: The results of this study showed that auricular acupressure was effective in increasing the accuracy of breaking in taekwondo players.

• Advances in nano research
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• v.14 no.6
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• pp.591-602
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• 2023

In the present study, capability of nanobiotics in repairing tendon injuries commonly occur in Taekwondo sport is investigated and some approaches are proposed. In this regard, a brief review on the types and application of nanobiotics is presented. Their capabilities and limitation are discussed. Next, different type of tendon injuries in Taekwondo athletes are discussed along with their treatment approaches. Based on the presented data, a nano-scale feasible robot model carrying nanobiotics is proposed for repairing tendons. Finite element simulations is also conducted to show the effectiveness of the repairing process using nanorobots equipped with nanobiotics. This repairing procedure is a combination of mechanical and chemical treatments. The results indicated that using nanobiotics on nanorobots arms in the repair of tendon injuries has many benefits. First, drug delivery is directly injected to the target section. Second, Due to the nanorobots small sizes more acute treatment is possible. Finally, since the control of the nanorobots are assisted with computers, the possibility of human error reduces significantly. The proposed method of the present study could be utilized by other scientists and technological industry in developing final nanorobots with nanobiotics carrying capacity.

• The Korean Journal of Physiology
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• v.15 no.1
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• pp.45-51
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• 1981

The aim of this study was to investigate the pulmonary function tests of athletes related to Running, Swimming, Cycle, Taekwando, Wrestling, Boxing, Yudo, Badminton, Base-ball, Soccer, Hand-ball, Basket-ball and Volley-ball. Subjects were 269 athletes from 18 to 22 years of age. They were college students and citizens. The results are as follows: 1) Frequency of breath: (cycles/min., $M{\pm}S.D$) Running shows $13{\pm}3.6$, Swimming $12{\pm}3.2$, Cycle $13{\pm}3.4$, Taekwondo $12{\pm}4.0$, Wrestling $14{\pm}2.5$, Boxing $15{\pm}4.5$, Yudo $13{\pm}3.2$, Badminton $14{\pm}5.7$, Base-ball $15{\pm}6.2$, Soccer $13{\pm}2.5$, Hand-ball $14{\pm}2.5$, Basket-ball $12{\pm}5.6$, Volley-ball $12{\pm}4.2$(Table 2, Fig. 1). 2) Vital capacity: (1, $M{\pm}S.D$) Running shows $4.29{\pm}0.634$, Swimming $4.30{\pm}0.608$, Cycle $4.08{\pm}0.718$, Taekwondo $4.32{\pm}0.595$, Wrestling $4.40{\pm}0.663$, Boxing $4.45{\pm}0.779$, Yudo $4.58{\pm}0.389$, Badminton $3.98{\pm}0.556$, Base-ball $3.99{\pm}0.617$, Soccer $4.42{\pm}0.728$, Hand-ball $4.23{\pm}0.397$, Basket-ball $4.28{\pm}0.426$, Volley-ball $4.60{\pm}0.620$(Table 2, Table 3, Fig. 2). 3) Tidal volume: (ml, $M{\pm}S.D$) Running shows $615{\pm}180$, Swimming $603{\pm}121$, Cycle $529{\pm}189$, Taekwondo $726{\pm}112$, Wrestling $512{\pm}90$, Boxing$622{\pm}134$, Yudo $583{\pm}89$, Badminton $672{\pm}121$, Base-ball $714{\pm}97$, Soccer $579{\pm}89$, Hand-ball $507{\pm}69$, Basket-ball $628{\pm}133$, Volley-ball $597{\pm}144$(Table 2, Fig.3). 4) Breath holding time : (sec., $M{\pm}S.D$) Running shows $64{\pm}18.8$, Swimming $81{\pm}23.0$, Cycle $54{\pm}13.6$, Taekwondo $55{\pm}11.8$, Wrestling $78{\pm}12.5$, Boxing $63{\pm}9.6$, Yudo $71{\pm}14.4$, Badminton $62{\pm}9.8$, Base-ball $58{\pm}8.9$, Soccer $65{\pm}10.9$, Hand-ball $66{\pm}7.6$, Basket-ball $62{\pm}8.8$, Volley-ball $57{\pm}13.4$(Table 2, Fig.4).

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.285-293
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• 2012

The aim of this study is to identify the appropriate movement for maintaining postural balance during Front Kick and Turning Side Kick motions. To do so, ten Taekwondo athletes: five skilled players(S, body mass: $65.0{\pm}5.8kg$, height: $172.3{\pm}3.7cm$, age: $20.0{\pm}1.2yrs$, career: $9.0{\pm}1.9yrs$) and five less-skilled players(LS, body mass: $67.1{\pm}5.5kg$, height: $173.2{\pm}5.1cm$, age: $19.4{\pm}1.7yrs$, career: $9.6{\pm}1.7yrs$) participated in this study. A three-dimensional motion analysis was performed on the participants using eight infrared cameras and two force plate(sampling frequency of 200 Hz and 2000 Hz for S and LS players, respectively). The participants' motions were divided into: a front-kick phase(P1) and a turning-side-kick phase(P2). For P2(p<.05), the range and root mean square(RMS) of the ground reaction torque and the M-L mean velocity of COP were greater for LS than for S; similarly, for P2(p<.05), the M-L range, A-P range, and velocity of the COP were greater for LS than for S. Further, the M-L range and maximum velocity of the COP was greater for failure than for success(p<.05). The femoral biceps muscle for bending the knee joint was significantly stronger in S than in LS(p<.05). It is expected that these results will be useful in developing a training program for improving the balance and stability of Taekwondo poomsae athletes and improve their front-kick and turning-side-kick motions.

• Nutritional Sciences
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• v.8 no.2
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• pp.118-124
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• 2005

To examine the eating attitudes, weight concerns, dietary intake, and menstrual function of Korean female elite athletes, 109 subjects in seven sports disciplines (rhythmic gymnastics, synchronized swimming, badminton, volleyball, Taekwondo, field hockey, and soccer) responded to a questionnaire consisted of three parts; eating attitudes and behavior(Eating Attitude Test-26; EAT26), body weight perception (Body Dissatisfaction Index: BDI) and weight control behavior, and menstrual history and status. They also recorded three-day dietary intake. Body weight (43.6$\pm$4.3 kg) and body mass index (16.7$\pm$1.4 kg/$m^2$) in rhythmic gymnasts were lower than those in other athletes (P<0.05). EAT26 scores were not different among sport events (12.3$\pm$6.5 total), however, eating disturbances (EAT26 score$\geq$20) were highly prevalent in aesthetic athletes ($30\%$) than in others ($5\%$). More than half of the athletes perceived themselves overweight and four fifth of the athletes desired to reduce weight about 4.4 kg. The gymnasts consumed the lowest caloric intake (1028:t371) while the volleyball players did the highest (2995$\pm$342 kcal/d) (P<0.05). The BDI score was not different among sport events. Three fourth of the athletes experienced weight control, and the most frequently used weight reduction method was exercise followed by using robber suits, diet, and sauna. About $40\%$ of the subjects reported irregular menstrual cycles, but menstrual dysfunction ($\leq$6 menses/yr) was only $5\%$. Generally, the Korean female elite athletes desired to reduce weight from their current body weight. No differences in eating attitude and body dissatisfaction were noticed among athletic disciplines. However, eating disturbances were highly prevalent in aesthetic athletes who also reported much less energy intake than the recommend daily energy intake. It appeared that weight reduction methods were not properly practiced in these population. Menstrual dysfunction was minimally reported.

• Journal of the Korea Society of Computer and Information
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• v.27 no.4
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• pp.89-97
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• 2022

This research intends the provide the influence of emotional intelligence and resilience on burnout of University sports athletes. For this purpose, purposive sampling method was used. The subject of this study were 257 University sports athletes from Korea. Data were collected through the self-administrated questionaire which were used by preceding study. The frequency analysis, factor analysis, correlation analysis and multiple regression analysis were used to solve the research problems in this study. The conclusion were drawn as follows. First the emotion intelligence influenced to resilience significantly. Second, the emotion intelligence influenced to burnout partially. Third, the resilience influenced to burnout partially.

• The Journal of the Korea Contents Association
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• v.8 no.10
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• pp.301-308
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• 2008

The purpose of this study was to investigate the change of physical fitness, MDA, SOD after short-term weight reduction through exercise, food restriction and exhalation of sweat among Taekwondo players. The subjects ten male collage Taekwondo players with excellent practical skills, and more than seven years of experiences. They were asked to reduce about 5% of their body weight in seven days. Physical fitness levels were analyzed through grip strength, muscle endurance, flexibility, power, agility, balance, reaction time and MDA and SOD through blood test. The results of this study were as follows; First, there was no significant change in physical fitness due to short-term weight reduction in muscle strength, muscle endurance, flexibility, power, agility, balance and reaction time. Second, The change of MDA and SOD, resulting from short-term weight reduction did not show significant difference statistically. Therefore, the results of this study indicate that the Taekwondo players' short-term weight reduction of 5% of their body weight did not influence on their athletic performance and physiological capacity. Therefore athletes and coaches should endeavor to take exercise, dietary, and dehydration into consideration when conducting 5% of their body weight reduction in a week.

• 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.