Kinematical Analysis of Uchimata in Judo

( Sung Hyu Shin ),( Myoung Sung Son ),( Won Sub Kim ),( Seung Pil Choi ) 한국운동역학회 2005 한국운동역학회 논문 영문초록집 Vol.2005 No.-

Depth Jump 시 하지 관절 상해에 관한 운동역학적 분석

소재무,김윤지,이종희,서진희,정연옥,김광기 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

J. M. SO, Y. J. KIM, J. H. LEE, H. J. SEO, Y. O. CHUNG ? K. K. KIM. The analysis of lower extremities injury on depth jump. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 127-142, 2005. The purpose of this study was to analysis biomechanics of the lower extremities injury the heights(40cm, 60cm, 80cm) of jump box as performed depth jump motion by 6 females aerobic athletes and 6 non-experience females students. The event of depth jump were set to be drop, landing and jump. The depth jump motions on the force plate were filmed using a digital video cameras, and data were collected through the cinematography and force plate. On the basis of the results analyzed, the conclusions were drawn as follows: 1. The landing time of skill group was shorter than unskill group at 40cm, 60cm drop height during drop-landing-jump phase especially. The landing time of 60cm drop height was significant between two group(p<.05). 2. The peak GRF of sagittal and frontal direction following drop height improve was variety pattern and the peak vertical force of 40cm drop height was significantly(p<.05). 3. The magnitude of peak passive force was not increase to change the drop height. 4. The peak passive forces was significant at 40cm drop height between two groups(p<.05)

테니스 포핸드 스트로크 시 오픈스탠스의 족저압력분포의 변화

최지영,김승재,이의린 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

J. Y. CHOI, S. J. KIM, E. L. LEE. Change of Plantar Pressure Distribution of Open Stance during Forehand Stroke M Tennis. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 143-153, 2005. Recently among several tennis techniques forehand stroke has been greatly changed in the aspect of spin, grip and stance. The most fundamental factor among the three factors is the stance which consists of open, square and close stance and it is very important to know the patterns of plantar pressure distribution for the better understanding of forehand stroke. Therefore, the purpose of this study was to investigate the change of plantar pressure distribution in open stance during forehand stroke in tennis. Three high school tennis players were recruited for the study and required to perform forehand stroke five consecutive trials in the condition of open stance. The forehand strokes were filmed with two digital video cameras and measured with pedar system for plantar pressure. The plantar regions under the foot were divided into 3 regions, which were forefoot, midfoot, and rear foot. In conclusion, The plantar pressure of open stance during forehand stroke was distributed more largely to the right foot. The plantar pressure of open stance during forehand stroke was distributed more weight loads on forefoot of right than heel of right

평지와 오르막경사의 트레드밀 걷기와 달리기 동안 발보장구가 발바닥근막염과 관련된 발아치 스트레인에 미치는 영향

김승재,Stefanyshyn, Darren,김로빈 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

S. J. KIM, D. Stefanyshyn, R. B. KIM. Effects of Foot Orthotics on the Foot Arch Strain related to PIantar Fasciitis During Treadmill Level and Uphill Walking and Running. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 155-176, 2005. There is some evidence that one of major factors to produce plantar fasciitis depends on the magnitude of the foot arch strain. The orthotics that can reduce the foot arch strain during locomotion may be effective to prevent or treat plantar fasciitis. Therefore, the purpose of this study was to investigate the effect of control condition and three types of foot orthotics on 3-dimensional foot arch strain that can produce plantar fasciitis during treadmill level and uphill walking and running. Sixteen male subjects are recruited and the arch length and height strain according to three types of foot orthotics with respect to control condition were measured by using two digital video cameras. The first hypothesis which the comfort of foot orthotics would be increased from arch pad, half length orthotics to full length orthotics was mostly accepted. It suggested that the types of the foot orthotics could be properly prescribed according foot regions that is pain or abnormal. The second hypothesis which the foot arch strain can be reduced by foot orthotics during level heel-toe walking and running and the third hypothesis which the foot arch strain can be reduced by foot orthotics during uphill heel-toe walking and running were rejected. The foot arch length and height strain during walking and running showed small and subject-specific characteristics and could not be optimal biomechanical variable to prove the overall comfort. The forth hypothesis which the foot arch strain cannot be reduced by foot orthotics during uphill toe walking and running was accepted. With the foot arch length and height strain during uphill toe walking and running the windlass mechanism suggested by Hicks can be explained successfully and excessive uphill toe walking and running can be one of cause of plantar fasciitis. The dynamic investigation on the foot arch such as walking and running should be carefully observed with integrated insights considering ligaments and foot bones as well as plantar fascia, extrinsic muscles and tendons, and intrinsic muscles and tendons.

보행 속도 변화에 따른 발목 관절의 운동학적 분석과 하퇴 근육의 근전도 분석

문곤성 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

G. S. MOON, The kinematic analysis of the ankle joint and EMG analysis of the lower limbs muscle for the different walking speed. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 177-195, 2005. The purpose of this study was to analyze the kinematic variables of ankle joints and EMG signal of the lower limbs muscle activity for the different walking speed. The subjects were 6 males of twenties. It was classified into three different walking speed-0.75m/s, 1.25m/s, 1.75m/s. The walking performances were filmed by high speed video camera and EMG signal was gained by ME3000P8 Measurement Unit. Tibialis anterior(TA), Gastrocnemius medial head(GM), Gastrocnemius lateral head(GL), Ssoleus(SO) were selected for the dorsiflexion and plantarflexion of the ankle joint. The result of this study were as follows: 1. In the gait cycle, The time parameters for the phases were showed significant difference without the terminal stance phase and terminal swing phase for the different walking speed. 2. The angle of ankle joint was no significant difference for each time point and MDF, MPF but increasing walking speed the angle had the increasing pattern slightly. 3. The angular velocity of ankle joint was showed the significant difference for LHC, RTO, RKC, LHU, MPF and MDF point along the walking speed. 4. TA was showed about 2-3 times muscle activity at the 1.75m/s than 1.25m/s in some phases. And it was showed the similar muscle activity between the 0.75m/s and 1.25m/s but, showed a little much muscle activity in the 0.75m/s. GM was showed about 2-3 times muscle activity in the 1.75m/s than 1.25m/s, and even much muscle activity at the 0.75m/s than 1.25m/s in some phases. GL was showed increasing pattern of muscle activity specially in the initial swing phase as the walking speed increased. SO was showed about 3 times muscle activity in the 1.75m/s than 1.25m/s during the plantarflexion of ankle joint. It was showed the similar muscle activity between the 0.75m/s and 1.25m/s but, showed a little much muscle activity in the 1.25m/s.

하지 분절 각도에 따른 수의 등척성 수축(MVIC)시 근전도 비교

김정자,이민형,김연정,채원식,한윤수,권선옥 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

J. J. KIM, M. H. LEE, Y. J. KIM, W. S. CHAE, Y. S. HAN, O. KWON. Comparison of the maximum EMG levels recorded in maximum effort isometric contractions at five different knee flexion angles. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 197-206, 2005. The purpose of this study was to quantify the maximum EMG levels and determine if there are differences in these EMG levels with respect to different knee flexion angles. Eight university students with no known musculoskeletal disorders were recruited as the participants. The maximum voluntary isometric knee extensions and flexions were taken from each participant sat on the isokinetic exercise machine (Cybex 340) at five different knee flexion angles (10?30?50?70? 90?. After surface electrodes were attached to rectus femoris, vastus medialis, vastus laterlis, biceps femoris, and semitendinosus, maximum EMG levels at five different knee flexion angles were measured. The results showed that there was no significant difference in maximum EMG levels among five different knee flexion angles. Although there was no significant difference in EMG levels and were some variations among different knee flexion angles, the EMG signals of quadriceps in extension and biceps femoris in flexion were the greatest at 30? It seems that different joint angles or relative locations of body segments might affect the magnitude of EMG levels. Because the maximum EMG levels could change with a different knee flexion angle, an attempt should be made to more accurately measure these values. If then, %MVIC measure provides more reliable data and is most appropriate for EMG normalization.

스텝 운동 기구를 사용한 운동 시 발의 위치가 하지 근육 활동에 미치는 영향 분석

채원식 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

W. S. CHAE. Electromyographic Analyses of the effects of different foot positions during exercise on a stair-climbing machine. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 207-219, 2005. The purpose of this study was to determine the effect of the foot rotation on the lower limb muscles. Fourteen subjects performed step-up/step-down at a cadence of 80 beats/min, exercises with the foot neutral, 35?internally rotated, and 35?externally rotated, respectively. For each variable, a one-way analysis of variance (ANOVA) was used to determine whether there were significant differences between genders and among the eight types of jump. When a significant difference was found in jump type, post hoc analyses were performed using the Tukey procedure. A confidence level of p < .05 was used to determine statistical significance. The results showed that significant changes in averaged IEMG values occurred with the internal rotation of the foot in the lateral gastrocnemius during the knee extension, and in the of the foot produced a significantly lower Averaged IEMG values than the neutral foot position in the medial gastrocnemius. The results also found that the peak IEMG activity of the rectos femoris during the knee extension for the external rotation of the foot was significantly higher than the corresponding values in the neutral position of the foot, while the intenal rotaion of the foot exhibited a significant difference with the neutral position of the foot in the semitendinosus during the knee flexion. In general, the foot rotation position did not influence the average IEMG and Peak IEMG values of most muscles. The practice of adopting foot rotation to selectively strengthen individual muscles of the lower limb was not supported by this study. The external rotation of the foot produced high muscle activities in the quadriceps during the knee extension. For the knee extension, therefore, maintaining a laterally rotated position should be need for stable and comfortable position.

배드민턴 드롭샷 동작의 운동학적 분석

오정환,최수남,정익수 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

C. H. OH, S. N. CHOI, I. S. JEONG. Kinematic Analysis of the Badminton Drop-shot Motion. Korean Journal of Sport Biomechartics, Vol. 15, No. 1, pp. 221-235, 2005. The purpose of this study was to analyse badminton players' drop-shots, in order to make players understand the principles of drop-shot motion in badminton. Three dimensional analysis was used to measure movements such as the time required per section, the change of center of gravity, joint angle and speed, and joint speed. The results of this study revealed as follows: (1) top players are faster than amateurs in the total time required per section; (2) top players moved more in the x-axis and z-axis, while amateurs moved more in the y-axis; (3) the inclination of amateurs was greater than that of top players in all phases; (4) amateurs showed larger angle on the shoulder joints than top players in the first phase, while top players showed larger angle on the shoulder joint than amateurs in the second and third phase. Amateurs' angle was larger on angle joint in the first phase than top players' ones, while top players' angle was larger in the third phase than amateurs; (5) the speed of racket head of top players was faster than that of amateurs; and the velocity of the center of gravity of amateurs was greater than that of the top players. The findings of this study were that gravity decreases during impact and then the velocity increases to perform the follow-through and making the swing fast by increasing the speed of the racket head is most important.

유도 허벅다리걸기 기술발휘 시 받기의 자세와 저항수준에 따른 중심변인 분석 사례연구(Ⅱ)

김의환,김성섭,정재욱 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

E. H. KIM, S. S. KIM, C. W. CHUNG. A Case Study on Center of Gravity Analysis when Performing ilchimata by Posture and Voluntary Resistance Levels of Uke in Judo[ II]. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 237.-257, 2005. It was to study as a following-research of "A Case Study on Center of Gravity(COG) Analysis when Performing Uchimata(inner thigh reaping throw) by Posture and Voluntary Resistance Levels(VRL) of Like in Judo[1]". The purpose of this study was to analyze the COG variables when performing uchimata(inner thigh reaping throw) by two postures and voluntary resistance Jevels(VRL) of uke(reciver) in Judo. The subjects, who were one male judoka(YH) for 1992 Barcelona Olympic Games Olympian(silver medalist), and one male trainee; Y.I.University representative member (SDK), and were filmed on two S-VHS 16mm video cameras(60fields/sec.) through 3-dimensional motion analysis methods, that postures of uke were shizenhontai (straight natural posture) and jigohontai(straight defensive posture), VRL of uke were 0% and 100%, respectively. The kinematical variable was COG variable, distance of COG, and distance of resultant COG between uke and tori(the thrower), velocity and acceleration of COG. The data of this study collection were digitized by SIMI Motion Program computed the mean values and the standard deviation calculated for each variables. When performing uchinwta according to each posture and VRL of uke and classifying. From the data analysis and discussion, the conclusions were as follows : 1. Displacement of COG Subject YH, COG was the highest in kuzushi(balance -breaking), vertical COG was low when following in tsukuri(positioning; set-up), kake(application; execution), and COG was pattern of same character each postures and resistance, respectively. Subject SDK, COG was low from kumikata(engagement positioning) to kake, and COG was that each postures and resistance were same patterns, respectively. Subject YH, SDK, each individual, postures and resistance, vertical COG was the lowest in kake phase, when performing. 2. Distance of COG between uke and tori The distance of COG between uke and tori when performing, subject YH was 0.64-0.70cm in kumikata, 0.19-0.28cm in kake, and SDK was 0.68-0.72cm in kumikata, 0.30-0.42 cm in kake. SDK was wider than YH. 3. Distance of resultant COG between uke and tori The distance of resultant COG between uke and tori when performing, subject YH was 0.27-0.73cm from kumikata to kake. and SDK was 0.14-0.34cm in kumikata, 0.28- 0.65cm in kake. Jigohontai(YH:0.43-0.73cm,SDK:0.59-0.65cm) was more moved than shizenhontai(YH:0.27-0.53cm, SDK: 0.28- 0.34cm). 4. Velocity of COG The velocity of COG when performing uchimata, subject YH was fast anterior-posterior direction in kuzushi, ant-post. and vertical direction fast in tsukuri and kake. SDK was lateral, ant.-post. and vertical direction in kuzushi, ant.-post. and vertical direction in tsukuri and ant.-post. direction in kake, respectively. 5. Acceleration of COG The acceleration of COG when performing uchimata, The trend of subject YH was showed fast vertical direction in kuzushi and tsukuri, ant-post. and vertical direction fast in kake. The trends of SDK showed lateral direction in kuzushi, lateral and ant.-post. direction in tsukuri and ant.-post direction in kake, respectively.

남자 스포츠 에어로빅스 선수의 Depth Jump시 하지관절에 대한 운동역학적 분석-사례 연구

김윤지 한국운동역학회 2005 한국운동역학회지 Vol.15 No.1

Y. J. KIM. The kinematic and kinetic analysis of lower extremities for male sports athletes during depth jumps - a case study. Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 259-274, 2005. The purpose of this study was to compare the kinematic and kinetic parameters of lower extremity joints between novice and experienced sports aerobic dancers during two heights of depth jumps. Four male dancers were participated in this study and they performed 40cm and 60 cm height depth jump three times, respectively. Four ProReflex MCU cameras (100frame/sec) and a Kistler force plate (1000Hz) were used for data collection. The results indicated that the duration of contact phase of experienced group was shorter than that of novice group regardless of jump height. For minimum angle of hip, knee, and ankle joints, the novice group had tendency to decrease the angle but the experienced group had increased the joint angle with jump height. There was no difference of total ground reaction force between the groups but the reaction force had tendency to increase with jump height. Thus, this study implied that repetition of jump and landing may induce joint related injury and further study such as EMG analysis of lower extremity can be needed to verify the relationship between injury and ground reaction force.