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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Journal of Sport Biomechanics
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Journal DOI :
Korean Society of Sport Biomechanics
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Volume & Issues
Volume 14, Issue 3 - Dec 2004
Volume 14, Issue 2 - Aug 2004
Volume 14, Issue 1 - Apr 2004
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The Three Dimensional Analysis of the Upper Body's Segments of the Elderly during Walking
Kim, Hee-Su ; Yoon, Hee-Joong ; Ryu, Ji-Seon ; Kim, Tae-Sam ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 1~15
DOI : 10.5103/KJSB.2004.14.3.001
The purpose of this study was to investigate the kinematic variables of the upper part of the body for 8 elderly men during walking. For this study, kinematic data were collected using a six-camera (240Hz) Qualisys ProReflex system. The room coordinate system was right-handed and fixed in space, with righted orthogonal segment coordinate systems defined for the head, trunk, and pelvis. Based on a rigid body model, reflective marker triads were attached on the 3 segments. Three-dimensional Cartesian coordinates for each marker were determined at the time of recording using a nonlinear transformation(NLT) technique with ProReflex software (Qualisys, Inc.). Coordinate data were low-pass filtered using a fourth-order Butterworth with cutoff frequency of 6Hz. Three-dimensional angles of the head, trunk, and pelvis segment were determined using a Cardan method. On the basis of each segment angle, angle-angle plot used to estimated the movement coordinations between segments. The conclusions were as follows; (1) During the support phase of walking, the elderly people generally kept their, head the flexional and abductional posture. Particularly, the elderly displayed little internal/external rotation. (2) The elderly people showed extensional and external rotation postures in the trunk movement. Particularly, It showed the change from adduction into abduction at the heel contact event of the stance phase. (3) The elderly people showed almost same pelvis movement from the flexion into extension, from the abduction into adduction, and from internal rotation into external rotation at the mid stance and toe off of the stance phase.
Coordinated Intra-Limb Relationships and Control in Gait Development Via the Angle-Angle Diagram
Lee, Kyung-Ok ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 17~35
DOI : 10.5103/KJSB.2004.14.3.017
The purpose of this study is to explain developmental process of gait via angle-angle diagram to understand how coordinated relationships and control change with age. Twenty four female children, from one to five years of age were the test subjects for this study, and their results were compared to a control group consisting of twenty one adult females. The Vicon 370 CCD camera, VCR, video timer, monitor, and audio visual mixer was utilized to graph the gait cycle for all test subjects. Both coordinated Intra-limb relationships, and range of motion and timing according to quadrant were explained through the angle angle diagram. Movement in the sagittal plane showed both coordinated relationships and control earlier than movement in the coronal or transverse plane. In the sagittal plane, hip and Knee coordinated relationships developed first (from one year of age.) Coordinated relationships in the Knee and ankle and hip and ankle developed next, respectively. Both hip and ankle and knee and ankle development were inhibited by the inability of children to completely perform plantar flexion during the swing and initial double limb support phases. Children appeared to compensate for this by extending at their hip joint more than adults during the third phase, final double limb support. In many cases the angle angle diagram for children had a similar shape as adult's angle angle diagram. This shows that children can coordinate their movements at an early age. However, the magnitudes and timing of children's angle angle diagrams still varied greatly from adults, even at five years of age. This indicates that even at this age, children still do not possess full control of their movements.
Comparision and analysis about gait parameters based on personality types through MBTI Test
Park, Sung-Hyun ; Kim, Jung-Tae ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 37~47
DOI : 10.5103/KJSB.2004.14.3.037
This study was designed to understand gait pattern on the MBTI personality types by analyzing and figuring out specific charges, which includes analyzing gait parameter which was shown in walking movement. The personality types was measured by the standard MBTI(Myers- Briggs Type Indicator) test and gait analysis make used of GAITRite program. The objects of research were convenience sampled student of M College. Temporal and spatial parameters were calculated based on the MBTI personality types test using measured data, 68 items and SPSS pc/program was conducted to find out specific changes and obtainted the results as follows. There was not found significant in rate of swing phase and stance phase, step length, stride length, base of support, toe in/out between Extraversion group and Introversion group. But Extraversion group was significantly higher than Introversion group in velocity and cadence(p<.05). Sensing group was significantly more than iNtuiton group in cadence. There was not found significant in all parameter between Thinking group and Feeling group, Judging group and Perceiving group.
Development of Posture Evaluation System through Digital Recognition Method
Moon, Young-Jin ; Lee, Soon-Ho ; Back, Jin-Ho ; Lee, Jong-Gak ; Lee, Gun-Bum ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 49~65
DOI : 10.5103/KJSB.2004.14.3.049
The purpose of this study is development of posture evaluation and Range of Motion(ROM) system by using digital vision analysis method. The results of this study are as follows. First, Scoliosis evaluation through this research measurement system represent 3mm error in 7 cervical point and deepest lumbar point, 0.7mm error in other point. This mean this research measurement system have a reliability for scoliosis evaluation. Second, for spine line evaluation on high fat subject, we need reconstrection spine line after measurement for fat thickness in 7 cervical point and deepest lumbar point. Third, In pedioscope error test, it present 0.01848cm in X axis and 0.01757cm in Y axis. This results mean pedioscope have a reliability foot evaluation. Forth, Posture evaluation and Range of Motion measurement system by using digital vision analysis method can fast measure in range of motion and foot evaluation and posture. therefore we can expect this system application in young people posture clinic center and hospital and so on.
The Evaluation of an additional Weight Shoe's Function developed for the Improvement of Aerobic Capacity
Kwak, Chang-Soo ; Kim, Hee-Suk ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 67~82
DOI : 10.5103/KJSB.2004.14.3.067
The purpose of this study was to evaluate the function and the safety of an additional weight shoe developed for the improvement of aerobic capacity, and to improve some problems found by subject's test for an additional weight shoe. The subjects employed for this study were 10 college students. 4 video cameras, AMTI force platform and Pedar insole pressure distribution measurement device were used to analyze foot motions. The results of the study were as follows: 1 The initial achilles tendon angle and initial rearfoot pronation angle of an additional weight shoe during walking were 183.7 deg and 2.33 deg, respectively, and smaller than a barefoot condition. Maximum achilles tendon angle and the angular displacement of achilles tendon angle were 185.35 deg and 4.21 deg respectively, and smaller than barefoot condition. Thus rearfoot stability variables were within the permission value for safety. 2. Maximal anterior posterior ground reaction force of additional weight shoe was appeared to be 1.01-1.2 B.W., and was bigger than a barefoot condition. The time to MAPGRF of an additional weight shoe was longer than a barefoot condition. Maximal vertical ground reaction force of additional weight shoe was appeared to be 2.3-2.7 B.W., and was bigger than a barefoot condition in propulsive force region. But A barefoot condition was bigger in braking force region. The time to MVGRF of an additional weight shoe was longer than a barefoot condition. 3. Regional peak pressure was bigger in medial region than in lateral region in contrast to conventional running shoes. The instant of regional peak pressure was M1-M2-M7-M4-M6-M5 -M3, and differed form conventional running shoes. Regional Impulse was shown to be abnormal patterns. There were no evidences that an additional weight shoe would have function and safety problems through the analysis of rearfoot control and ground reaction force during walking. However, There appeared to have small problem in pressure distribution. It was considered that it would be possible to redesign the inner geometry. This study could not find out safety on human body and exercise effects because of short term research period. Therefore long term study on subject's test would be necessary in the future study.
A comparison study for mask plantar pressure measures to the difference of shoes in 20 female
Kim, Y.J. ; Ji, J.G. ; Kim, J.T. ; Hong, J.H. ; Lee, J.S. ; Lee, H.S. ; Park, S.B. ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 83~98
DOI : 10.5103/KJSB.2004.14.3.083
The purpose of this study was to investigate the test-retest of plantar pressures using the F-Scan system over speeds and plantar regions. 6 healthy female subjects in 20's were recruited for the study. Plantar pressure measurements during locomotor activities can provide information concerning foot function, particularly if the timing and magnitude of the loading profile can be related to the location of specific foot structures such as the metatarsal heads. The Tekscan F-Scan system consists of a flexible, 0.18mm thick sole-shape having 1260 pressure sensors, the sensor insole was trimmed to fit the subjects' right. left shoes - sneakers shoes & dress shoes. It was calibrated by the known weight of the test subject standing on one foot. The Tekscan measurements show the insole pressure distribution as a function of the time. This finding has important implications for the development of plantar pressure test protocols where the function of the forefoot is important. According to the result of analysis it is as follows 1) Center of force trajectory in women's dress shoes display direct movement, compare with center of force trajectory in Sneaker shoes displays a little bit curved slow pronation movement. Sneaker shoes in forefoot part display very quick supination movement, therefore, this shoes effects negative effectiveness for ankle's stability Considering center of force trajectory analyzing the more center of force close straight line, the more movement can be quick movement for locomotion. For foot pressure distribution, center of force trajectory in locomotion is better to curved trajectory with pronation movement. So sneaker shoes style is good shoes considering center of pressure distribution trajectory compare with women's dress shoes. 2) Women's dress shoes increased peak pressure in medial, this is effected by high hill's height. The more increased women's dress shoes's height, the more women's peak pressure will increase, pronation can increase compare with before. Supination movement increase, this focused pressure in lateral, also, supination increased more. If the supination movement increased, foot pressure focused in lateral, therefore, it is appeared force distribution in gait direction. This is bad movement in foot's stability. 3) Women's dress shoes in landing phase displayed a long time, this is when women's dress shoes wear, gait movement is unbalance, so, landing phase displayed a long time. For compensation in gait, swing phase quick movement. 4) Women's dress shoes displayed peak pressure distribution in lateral of rearfoot part, Sneakers shoes displayed peak pressure distribution in medial of forefoot part. Its results has good impact absorption compare with women's dress shoes. In forefoot part, sneakers shoes has good propulsive force compare with women's dress shoes.
A Study of In-sole Plantar Pressure Distribution in Functional Tennis Shoes
Lee, J.S. ; Kim, Y.J. ; Park, S.B. ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 99~118
DOI : 10.5103/KJSB.2004.14.3.099
The aim of this study is to evaluate tennis shoes's plantar pressure distribution in tennis prayers and to determine the influence of the shoe on various tennis movements. When investigating the biomechanics of movement in tennis, one of the first things to do is to understand the movement patterns of the sport, specifically how these patterns relate to different tennis shoes. Once these patterns are understood, footwear company can design tennis shoes that match the individual needs of tennis players. Plantar pressure measurement is widely employed to study foot function, the mechanical pathogenesis for foot disease and as a diagnostic and outcome measurement tool for many performance. Measurements were taken of plantar pressure distribution across the foot and using F-Scan(Tekscan Inc.) systems respectively. The F-Scan system for dynamic in-shoe foot pressure measurements has enabled us to assess quantitatively the efficacy of different types of footwear in reducing foot pressures. The Tekscan F-Scan system consists of a flexible, 0.18mm thick sole-shape having 1260 pressure sensors, the sensor insole was trimmed to fit the subjects' right, left shoes. For this study 4 university male, high level tennis players were instructed to hit alternated forehand stroke, backhand stroke, forehand volley, backhand volley, smash, service movement in 4 different tennis shoes. 1. When impact in tennis movement, peak pressure distribution of landing foot displayed D>C>B>A, A displayed the best low pressure distribution. A style's tennis shoes will suggest prayer with high impact. If prayer with high impact feeling during pray in tennis wear A style, it will decrease injury, will have performance improvement. 2. When impact in tennis movement, plantar pattern of pressure distribution in landing foot displayed B>A>C>D in stability performance. During tennis, prayer want to stability movement suggest B style tennis shoes when tennis movement impact keep stability of human body. B style tennis shoes give performance improvement 3. When impact in tennis movement, plantar pattern of center of force(C.O.F.)trajectory in landing foot analyzed this : 1) When stroke movement and volley movement in tennis, prayer better to rearfoot movement. 2) when service movement, prayer midfoot strike movement. 3) when smash movement, prayer have forefoot strike movement.
Analysis of the Angular Momentum for the Bar Clearance Motion in the Fosbury Flop
Sung, Rak-Joon ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 119~134
DOI : 10.5103/KJSB.2004.14.3.119
The purpose of this study was to analyze the angular momentum characteristics of the Fosbury Flop high jump and the role of the body segments for the production of 3 angular momentum components. The subjects were three male jumpers who were former Korean national team players. Their jumping motions were analyzed using the DLT method of three-dimensional cinematography. The conclusions were as follows. 1. All the forward angular momentum needed to clear the bar was created in the take-off phase. Take-off leg was the great contributor of the forward angular momentum. On the other hand, free leg produced large opposite angular momentum. 2. All subject had some lateral angular momentum before the take-off phase. Head and free leg had major contribution to the lateral angular momentum production. Take-off leg produced opposite angular momentum. 3. All subject had some twisting angular momentum, which make the back of the athlete him to the bar, before the take-off phase. Free leg was the major contributor of the twisting angular momentum. Head and trunk was the second contributor of the twisting angular momentum. 4. Total angular momentum needed to clear the bar had no significant correlation to the jumping height. 5. Subject who made excessive angular momentum showed different pattern of angular momentum production and had a poor record compared to other subject.
Biomechanical Analysis of Tsukahara Vault with Double Salto Backward Piked
Lim, Kyu-Chan ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 135~147
DOI : 10.5103/KJSB.2004.14.3.135
This study was conducted to investigate the technical factors of Lu Yu Fu vault actually performed by three men gymnasts participated in artistic gymnastics competition of 2003 summer Universiade in Daegu through the DLT method of three dimensional cinematography. To analyze these vaults, the instant events of Lu Yu Fu were set in the board touchdown(BTD), the board takeoff(BTO), the horse touchdown(HTD), the horse takeoff(HTO), the peak height(PH), the mat touchdown(MTD) respectively and the phases of that vault were set in the board contact(BC), the preflight(PRF), the horse contact(HC), the postflight(POF), the grounding on mat(GM) respectively After calculating the performance times, the CG displacement velocity, the kinetic energy impulse reaction force moment arm torque at the horse, the released angle piked angle addressed angle, the angular momentum angular velocity of whole body in x axis, and the horizontal displacement between the feet and CG, the following conclusions were reached. To perform the better Lu Yu Fu vault, a gymnast must have the large horizontal velocity of whole body with fast run-up, decrease the duration time and the horizontal vertical displacement of whole body in PRF, have the enough time to judge the correct magnitude and direction of force to brake or push the horse so as to lengthen the HC duration time at any cost. Also it is desirable to increase the horizontal vertical displacement of whole body in POF if possible, maintain the adequate piked position to decrease the angular velocity of whole body in x axis, prepare the grounding on mat previously and delay the release of the hand from the body to keep the angular momentum.
The Kinematic Analysis of Cross Over Step and Delivery Phase in Female Javelin Throwing Players
Lee, Young-Sun ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 149~163
DOI : 10.5103/KJSB.2004.14.3.149
This study analyzed kinematic variables about the cross step, the delivery and the release for women's javelin athletics recorded over 50m in the 2004 Busan International Athletics Competition. It was used the Kwon3D Motion Analysis Package Ver. 3.1 Program(Kwon, 2000) for analysing the kinematic variables about the distance, the velocity, and the angle, then we had the results as follows; 1 In the Cross step phase, the COG velocity was low because their step length was short. To keep the CM velocity from the approach to the last cross over step contact, the athletes have to keep the longer step length within about 130% of the athletics' height. 2. In the Delivery phase, the athletics' COG height was gradually lower, and the deceleration of the COG was going up. As the same in the cross step, Therefore the athletes have to increase the step length within about 100% of their height, in order to increasing the COG velocity. And it was shown they have to make small angle of the elbow as possible from the right foot contact to the left foot contact in order to being the big acceleration of the upperarm at the release phase. 3. In the release phase, it was shown to being low position of the release point as the COG was low and then the release velocity of the upperarm was low. Specially when the shoulder lean lateral angle is big at the release phase, it was shown they have a excessive release angle. And, when it was shown the high rotation angle of the shoulder, the shoulder was opened forward bigger than the trunk was opened forward. So the transmission of velocity from the proximal segments was a fast change.
Analysis of the angular momentum on the lower extremity by change of starting block angles
Shin, Sung-Hu ; Kim, Tae-Wan ; Kwon, Moon-Seok ; Go, Suk-Gon ; Park, Ki-Ja ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 165~175
DOI : 10.5103/KJSB.2004.14.3.165
The aim of this study is to show the effect of starting block angle on the starting motion of sprinters using a crouching start. After installing starting blocks on forced platform, and having four highly comparative sprinters use the starting blocks, I analyzed the angular momentum of a crouching start. From the results of the analysis, the following conclusions could be drawn: There were differences of angular momentum both in body's X, Y, and Z axes and in the thighs' X axes, but not in the pelvis and lower legs. As to the general change of block angle, we noticed that an angular momentum for each segments was higher at an angle of 50 to 55 degrees.
EMG Analysis for Investigation Muscle-Collaborated Relationship during Golf Swing
Shim, Tae-Yong ; Shin, Seong-Hyu ; Oh, Seung-Il ; Mun, Jung-Hwan ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 177~189
DOI : 10.5103/KJSB.2004.14.3.177
Kinematic and kinetic analysis using 3D Motion Capture system are common, yet there is little in the literature that discuss the relationship and coactivity between muscles during the golf swing. The purpose of this study was to describe the relationship between the employed 16 muscles during golf swing. We could observe 3 muscle patterns such as 'Line' shape, 'L' shape, and 'Loop' shape for the golf swing activity. The 'Line' shape indicates that two muscles act almost perfectly in phase, and the 'L' shape represents that two muscles act in a reciprocating manner(When one is active, the other is quiescent and vice versa). And the 'Loop' shape indicates that two muscles act sequently(After one is active, the other act). In these results, we knew the muscle patterns during golf swing is similar to the patterns during gait. And we presented it was possible to show the consistence of golf swing through the frequency analysis of muscle patterns. We believe that the results potentially useful for the golf players and coaches to analyze their performance.
The Movement of Foot and the Shift of Ground Reaction Force in Batters according to the Ball Speed Increase
Lee, Young-Suk ; Eun, Seon-Deok ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 191~202
DOI : 10.5103/KJSB.2004.14.3.191
The batting performance in baseball is a repetitive movement. In order to make the stabilization of posture and the efficient shift of body weight, both the range of stance and stride are important. The previous studies explained that the consistent stride which included the amount of time, stance, and direction were needed. However, the batting performance is frequently changed according to the several speed of ball. Therefore, this study was to analyze the reaction time, the range of stance, the change of stride, and the change of GRF during the batting movement in three kinds of ball speed (120km/h, 130km/h, & 140km/h). Seven elite players are participated in this study. 1. The reaction time of the stride phase was short whereas the time of the swing phase was long according to the increasing ball speed. 2. The range of the stance was wide and the mediolateral direction of the stride was decreased according to the increasing ball speed. 3. In the three kinds of ball speed, the change of body weight was transferred to the center, the rear foot, and the front foot directions. The ball speed of 130km/h showed the high frequency of the suitable batting. At this ball speed, the movement of the body weight was shifted smoothly and the value of the Ground Reaction Force was large enough.
A Kinematic Comparative Analysis of Yoko Ukemi(side breakfall) by Each Stage in Judo[ I ]
Kim, Eui-Hwan ; Kim, Sung-Sup ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 203~218
DOI : 10.5103/KJSB.2004.14.3.203
The purpose of this study was to analyze the comparisons of the kinematical variables when performing Yoko Ukemi(side breakfall) by three Stage in Judo. The subjects were four male judokas who were trainees Y. I. University Squad members and the Yoko Ukemi were filmed by two S-VHS 16mm video cameras(60fields/sec.). The selected times were subject to KWON 3D analysis program and kinematical analysis to compare variables of three Yoko Ukemi. Temporal variables(total time-required : TK, TR by each phase), the body part touched order on the mat and COG variables were computed through video analysis while performing right Yoko Ukemi by three stage. From the data analysis and discussion, the following conclusions were drawn : 1. Temporal variables : total time-required(TR) when performing Yoko Ukemi(side breakfall) by each stage, the first stage(full squat posture: FP : 1.11sec.) showed the shortest time, the next was 3rd(Shizenhontai, straight natural posture: NP : 1.41sec.), and 2nd(Jigohontai, straight defensive posture, DP : 1.42sec.), respectively- 2. TR when performing Yoko Ukemi(side breakfall) by each stage, and phase : the first phase(take of phase, average 0.68sec.) showed the longest time, next was the third phase(ukemi phase, 0.39sec.), and the second phase(air phase, 0.23sec.), respectively. 3. When performing yore Ukemi the body part touched order and TR on the mat : hip(0.94sec.) showed the shortest time, the next was elbow hand(0.97sec.), back(0.98sec.), and shoulder(1.04sec.) order. The hip part touched on the mat the first, but slap the mat in order to alleviate the shock try hand palm and forearm before receiving impact (difference 0.03sec,) 4. Vertical COG variables in each event by each stage : e1(ready position, average 78.33cm) moved the highest, the next was e2(jumping position, 70.14cm), e3(transition position, average 64.00cm), e4(landing position, average 35.99cm), and e5(ukemi position, average 18.32cm) order, gradual decrease respectively. And the difference of COG were showed in initial by each stage, because position fo Yoko Ukemi was difference by each stage in preparation position, but in accordance with executing of Ukemi phase that difference of COG was by decreasing, almost equal displacement in e4(landing) and e5(Ukemi)position finally.
Study of the forearm EMG activities during Kumdo head striking
Jang, Eon-Ryang ; Park, Young-Hoon ; Youm, Chang-Hong ; Seo, Kuk-Woong ; Noh, Suk-Gyo ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 219~233
DOI : 10.5103/KJSB.2004.14.3.219
The purpose of this study was to compare the EMG activities of four-forearm muscles during Kumdo head striking. The four skilled and unskilled Kumdo club members were selected from D university in B city. Investigated muscles were left brachioradialis, right brachioradialis and left flexor carpi radialis, right flexor carpi radialis. Raw EMG data were collected during the head striking motions and the average EMG were calculated by the frame width of 0.05s, and then the average %MVC were calculated. The average %MVC values of each muscle in each group were compared. The results are as follows. 1) In each group, there were no significant statistical differences between every muscle over the all phases. 2) There were significant differences, however, between skilled group and unskilled group. The former got higher average %MVC at left flexor carpi radialis and the latter at right brachioradialis in the ready phase and in the impact phase.
A Case Study on Kinematical Traits Analysis when Performing of Uchimatia(inner thigh reaping throw) by Posture and Voluntary Resistance Levels(VRL) of Uke in Judo[ I ]
Kim, Eui-Hwan ; Yoon, Hyun ; Kim, Sung-Sup ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 235~257
DOI : 10.5103/KJSB.2004.14.3.235
The purpose of this study was to analyze the kinematical traits variables when performing Uchimata(inner thigh reaping throw) by Voluntary Resistance Levels(VRL) and two postures of Uke in Judo. The subjects, who were one male judoka(YH) for 1992 Barcelona Olympic Games, and one male trainee Y. I. University representative member(SDK) and were filmed on two S-VHS 16 mm video cameras(60fields/sec.), that posture of Uke were Shizenhontai(straight defensive posture) and Jigohontai(straight natural posture), VRL of Uke were 0% and 100%. The kinematical variables were temporal(total time-required: TR), potures and COG variables etc., 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 according to each posture and VRL, from the data analysis and discussion, the conclusions were as follows : 1. Temporal variables total time-required(TR) when performing Uchimata was shown the shortest time YH than SDK by each posture and VRL. TR of each posture were shown the shorten trends or equal in DP by lower than NP, In existence and / or nonexistence of VRL was shown the shorten trends in VRL 0% than 100% of Uke. 2. Posture variables : In attacking right knee angle, YH was performing flexion(
) from Tsukuri(set-up) to Kake(execution) in regardless of postures and VRLs, SDK was performing not exchange extension and flexion in VRL 100%, and extension(
) in VRL 0%, respectively. In supporting left hee angle, YH was performing extension(
) from Tsukuri(set-up) to Kake(at(execution) in regardless of postures and VRLs, SDK extension(
), respectively. In attacking right hip angle, from Tsukuri to Kake, YH was performing extension(
), except in VRL 0%(
) NP, SDK was performing flexion(
) accept in VRL 100%(
) NP, In left hip angle, from Tsukuri to Kake, YH was performing flexion NP(70, 50degree) more than DP(27, 57degree), SDK was performing flexion DP(73, 52degree) more than NP(34, 20degree). 3. COG variables : When performing Uchimata, vertical COG variables was shown YH(:
) lower than Uke's COG level position, in existence and / or nonexistence of postures and VRL, during Kake as maximum force point of throwing techniques in Judo.
Kinmatics Analysis of pelvis and lower extremity using orientation angles during a developpe a la seconde
Jung, Chul-Jung ; Jeung, He-Jin ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 259~270
DOI : 10.5103/KJSB.2004.14.3.259
The purpose of this study was to analysis of pelvis and lower extremity using orientation angles during a developpe a la seconde. Data were collected by Kwon3D program. Two females professional modem dancer were participated in this experiment. Subjects performed a developpe a la seconde in meddle heights(about 90 dog.) The results were as follows. The orientation angles of pelvis were, in most cases, caused by the movement of trunk and thigh. It was restricted the movement of pelvis within narrow limits because the movement of pelvis was very important to lower extremity alignment. The orientation angle of shank against thigh showed a change of angle about
in internal external rotation. The orientation angle of foot against shank showed a change of angle about
in internal external rotation.
The effects of EMG activity and blood fatigue makers on balance taping treatment by exercise type
Lee, Hyo-Seong ; Lee, Yong-Sik ; Byun, Jae-Chul ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 271~284
DOI : 10.5103/KJSB.2004.14.3.271
The purpose of this study was to analyse the EMG activity of selected muscles with balance taping treatment and blood fatigue makers which accumulated during exercise of progressive maximal intensity. Ten male college students who did not experience any cardiovascular and musculo-skeletal disease were participated in this study. Balance taping were applied to rectus femoris, vastus medialis, vastus lateralis, biceps femoris, semitendinous, semimembranous, and around knee joint. Isokinetic knee joint flexion/extension force, EMG activity, lactate and ammonia as blood fatigue makers during progressive maximal intensity exercise were measured for with/without applying balance taping. The results indicated that although flexion force of total work at
with taping was increased applied taping did not affect to the aerobic exercise ability parameters. Lactate level as blood fatigue makers during progressive maximal intensity exercise after taping was decreased but the ammonia level did not change with same treatment. In isokinetic knee joint test at the angular velocity of
the taping treatment did not affect to any selected muscle EMG activities except maximal EMG of vastus lateralis at
Analysis of the Female 500m Sprint Starting Motion in Short Track Speed Skating
Back, Jin-Ho ; Kwak, Chang-Soo ; Chung, Nam-Ju ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 285~299
DOI : 10.5103/KJSB.2004.14.3.285
The purpose of this study is to identify female 500m sprint start motion by the center of gravity position in short track speed skating. The center of gravity position ratio was divided into three type(type A front : 80%-back : 20%, type B front : 70%-back 30%, type C front: 50%-back : 50%). Three video cameras were used for 3D motion analysis with DLT method and the results were as follows: The elapsed time in starting motion was appeared that type B was the shortest and type A was the longest. It was appear that the stroke length of type A was longer than that type B and C during starting phase. This result was similar to displacement of center of gravity. It was appeared that skill type of center of gravity position ratio type B' ankle and knee joint angle were lower than that of type A and C. Observing these results it was conclusion that skill type B of center of gravity position ratio was more faster than that of type A and C. But it is important that these skill type needed to verifying more subjects.
Mathcad program as a useful tool for the teaching and studying the sport biomechanics
Sung, Rak-Joon ;
Korean Journal of Sport Biomechanics, volume 14, issue 3, 2004, Pages 301~311
DOI : 10.5103/KJSB.2004.14.3.301
The purpose of this study was to verify the usefulness of the Mathcad program as a tool for the studying and teaching the sport biomechanics. A projectile motion was analyzed because it is the one of the most popular motion in sports activities. A 3 dimensional CG data for the high jump bar clear phase was used to calculate the initial velocity vector of the CG. Linear regression function and other functions such as cubic spline and derivative of Mathcad were used to calculate this vector. Finally, the approach angle to the bar and peak jump height was calculated. Programming in Mathcad was relatively easy compare to traditional computer language such as Fortran and C, because of the unique documentation method of Mathcad. Additionally the 2 and 3 dimensional graph function was very easy and useful to describe the mechanical data. If the use of Mathcad program is more popular in the field of sport biomechanics, it could greatly contribute to overcome the limit of research caused by the lack of proper programming ability.