• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.17-32
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• 2002

The purpose of this study was to find the rational method to analyze golf swing with specific property of club shaft. Three subjects were filmed by two high speed digital cameras with 500 fps. The phase analyzed was downswing of each subject. The three-dimensional coordinates of the anatomical landmarks were obtained with motion analysis system Kwon3d 3.0 version and smoothed by lowpass digital filter with cutoff frequency 6Hz. From these data, kinematic and kinetic variables were calculated using Matlab(ver 5.0) The variables for this study were angular velocity and accelerations, which were calculated and following conclusions have been made : 1) Golf swing time of stiff club is faster than that of regular club. 2) In shoulder joint motion of swing with the stiff club, x-stiff showed mort rapid negative acceleration than that of regular club. 3) In regular club, the velocity of club head would be more effective velocity, which was increasing, than those of other clubs before impact. 4) In wrist joint motion of swing with stiff club, x-stiff club showed faster than regular club in the downswing and impact more rapid negative acceleration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3902-3909
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• 2009

The purpose of this study was to investigate the spontaneous therapy, TENS(transcutaneous electrical nerve stimulation) and ice therapy after induction of DOMS(delayed onset muscle soreness) through application of eccentrically exercise in ralation to biceps brachii muscle of opposite-dominance. And to explain this, we analyzed VAS(visual analogue scales), peak torque, RMS(roots mean square) when exercising elbow joint. The subjects were 30 adults without any physical defect. Subjects were divided into three groups that spontaneous therapy, TENS therapy and ice therapy after DOMS induction, choosen movement could get the maximal peak torque in angular velocity of $60^{\circ}$/sec, and mearsured peak torque, RMS and VAS. 1. The VAS was significantly decreased after 3 days application of TENS than other groups(p<.05). 2. The peak torque was significantly increased after 3 days application of TENS than other groups(p<.05). 3. The RMS was significantly increased after 3 days application of TENS than other groups(p<.05). This study showed that TENS therapy application were effective treatment strategy on DOMS than spontaneous therapy and ice therapy. Therefore, it could be considered as a treatment method in the patients with DOMS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.167-174
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• 2020

The purpose of this study was to investigate the kinematic comparison between successful and failed trials of Lopez vault techniques in male gymnastics. The subject, an Olympic gold medalist, was YHS (age: 27 years, height: 1.6 m, and mass: 53 kg) and fourteen high speed motion capturing cameras were used for data collection. The 26 reflective sensors were attached on major anatomical positions and 15 segment-body model was used to calculate the kinematic variables. According to results, the contact duration of the spring-board for successful trial(ST) was longer and that of failed trial(FT) and the range of motion of knee joint for ST was greater than that of FT. The movement times during pre-flight between ST and FT were same, but the movement time of horse contact period for ST was shorter than that of FT. The ST showed a longer movement time during post-flight and the longer horizontal distance than those of FT. Conclusively, YHS needs to approach the horse with a higher position of the body and higher incidence angle, as well as make faster twist angular velocity in an attempt to achieve ST.