자연과학편 : 평행봉(平行棒) Slide Kip동작(動作)의 비교분석(比較分析)

박광동(KwangDongPark) 한국체육학회 1987 한국체육학회지 Vol.26 No.1

The Purpose of this study is to analyze the motion of Slide Kip, one of basic skill in parellel bars, with computer. Two university players, subject A can perfect motion but B con not, were rendomly sampled as subjects.The writer Photoed their motion Several times with 16mm movie camera(64frame/sec). Films were projected with motion analyzer and misphotoed films were excluded. And among the rest, the film of the most correct motion was selected. 20 portions(Matsui’s drawing method) were Pointed with stylus pen and bata were output by computer. The motion of Slide Kip was divided into 5 phase and the moving Velosity of the gravitational center of the body and the changes of angle of joints were analyzed.The conclusions were as follows:1. In phase 1, subject A flexed more than B by 3.31˚ at neck joint, 4.09˚ at hip joint, and 5.81˚ at shoulder joint and moved faster than B by 1.33m/sec of HV, -0.40m/sec VV, and 1.09m/sec of RV.2. In phase 2, subject A flexed more than B by 11.69˚ at hip joint and 7.26˚ at shouleder joint At neck joint, subject A extend 29.72˚, but B flexed 19.91˚.3. In phase 3, subject A moved faster than B by 0.14m/sec of HV, 0.58m/sec of VV, and 0.34m/sec of RV and extend more than B by 36.53˚ at neck joint, 4.08˚ at hip joint, and 2.49˚ at shoulder joint.4. In phase 4, subject A moved slower than B by 0.92m/sec of HV and 0.13m/sec of RV, and faster than B by 0.22m/sec of VV. subject A flexed more than B by 14.06˚ at hip joint and 25.24˚ at shoulder joint, and subject B flexed more than A by 3.00˚ at neck joint.5. In phase 5 5, subject A extend more than B by 9.14˚ at neck joint and 5.93˚ at hip joint. At the end of phase 5, pushing up body by flexing neck joint and shoulder joint and straitening one by extending hip joint is thought to be desirable.6. In sum, success of the slide kip motion is due to hip position when hang inversely and kicking direction when lift body.

자연과학편 : 회전계 도마운동 발구름 동작의 역학적 분석

박광동(KwangDongPark) 한국체육학회 1993 한국체육학회지 Vol.32 No.2

The purpose of this study is to examine the mechanical characteristics of the last approch, the touch down on vaulting board, the take off, the preflight and the hand touch on long horse during the motion of handspring and Salto Forward Tucked on the long horse.Kinematic and Kinetic factors were analyzed in terms of cinematograpic analysis and force-platform which was fabricated by writer.10 male Gymnastic players were devided into two groups : each group is composed of five subjects on the basis of their performance.In terms of Cimematography, Kinematic factors such as time, displacement, velocity, angular rotations, angular velocity are studied and analyzed using force-platform.The results obtained form those two groups are as follows :1. Kinematic analysisThe experimental results show that the horizontal displacement of the total C. O. G. is 2.28m in group A which is composed of skilled players and 1.97m in groups B unskilled players.The mean difference between those two groups were significant(P<.051).Group A(0.56sec) moved faster than group B(0.57sec) in 0.01sec of the required time. However, this is not significant.The averge velocities were 2.59m/sec for the skilled group(A) and 2.49m/sec, 2.43m/sec for the unskilled group(B). This the difference of horizontal velocity was larger for group A than that for group B and the difference of vertical velocity vice versa.The test results showes a significant difference between two(P<.05).Group A contained more values than group B in the resultant velocity to the hand touch on vault this indicates that a significant difference exists between two(p<.05).For the horizontal acceleration of the approach phase. group A retains 0.48m/ sec² and group B-2.66m/sec², group A 2.61m/sec² and group B-2.66m/sec² in the vertical acceleration.The test result showes that there is no significant difference for the incidence angle and the reflex. angle between two. The incidence angle of group A is larger than that group 3 in 4deg. In contrast. The reflex angle of group A is smaller than of group B in 2deg.2.Kinetic AnalysisThe differences of forward and backward vertical forces were significant. The forward vertical forces were 234㎏ for group A and 169㎏ for group B. The backward vertical forces shown by group A in 34㎏ and group B in 29㎏.For the maximum vertical forces. group A showed 458㎏ and group B 408㎏ in the forward vertical force.However, group A showed 76㎏ and group B 99㎏ in the backward vertical forces. This indicates that the significant differences exist between two.3. Correlation of variable factorsThis research proved that board landing angle depend upon vertical velocity which has relevance of angle of hand touch on long horse.From this results, it can be seen that there is a positive correlation between horizontal velocity and angle of hand touch on long horse in the touch on vaulting board(r=0.72).Also, the test results shows that there is a positive correlation between vertical velocity and angle of hand touch on vault(r=0.49).On the other hand, there is a negative correlation between vertical velocity and angle of landing in the touch on vaulting board.4. This work supports that touch board and the take off angle velocity depend upon horizontal factors of the approch in the long horse of rotatory system.

운동 역학 : 철봉에서 KOVACS 동작 수행의 운동학적 분석

박광동(KwangDongPark) 한국체육학회 1997 한국체육학회지 Vol.36 No.1

이 연구의 목적은 철봉 KOVACS동작을 운동학적 변인들의 기술적 차이점을 비교하여 이 동작의 이상적인 지도방법과 선수들의 경기력 향상에 기초자료로 제공함에 있다.위의 목적을 달성하기 위하여 철봉에서 KOVACS동작을 수행할 수 있는 남자 국가 대표선수 2명과 대학 선수 1명을 임의 추출하여 운동학적인 변인들을 분석한 결과 다음과 같은 결론을 얻었다.어깨가 봉 위에서 봉과 수직을 이룬 자세에서 어깨가 봉과 수평을 이룬 자세까지는 긴 소요시간으로 견관절의 이완과 고관절의 굴곡이 여유있는 동작을 취하게 하며, 어깨가 봉과 수평을 이룬 자세에서 어깨가 봉 아래에서 봉과 수직을 이룬 자세까지는 신체를 layout시키면서 큰 원운동의 swing동작을 취하다가 어깨가 봉 아래에서 봉과 수직을 이룬 자세에서 봉에서 손이 떨어지는 순간까지는 빠른 소요시간으로 신체의 반작용을 이용하여 하지를 들어올리며, 봉에서 손이 떨어지는 순간에서 다시 봉에 손이 닿는 순간의 자세까지는 신체의 회전반경을 짧게 한 tuck자세를 취하여 빠른 회전을 한 후 bar를 잡는 것이 이 동작의 승패를 좌우하는 결정적인 요인이 된다. The purpose of this study is to compare the technical differences from thefactors of kinetic changes in the motion of KOVACS at horizontal bar in order to provide an ideal coaching method for the motion and improvement in players' conpetivity as a fundamental datum.For the achievement of such a purpose, two out of national level male champions and one university player have been selected as subjects, who were able to perform the KOVACS motion at horizontal bar.The analysis of the kinetic factor changes extracted from the atrandom selected subjects was resulted in a conclusion as follows.First, the changes of time favors as shown wer a period of long time in phase H · S to phase H · P; a duration of short time in phase V · P to phase Rel.; a long duration of time in phase Rel. to phase T · B, respectively were desirable.Second, the factors of velocity changes shown as resultant velocity in phase H · P; a horizontal velocity in phase V · P; another resultant velocity in phase Rel.; a horizontal velocity in phase P · H; and a horizontal and vertical velocity particularly in phase T · B.. All these factors were very essentialThird, the position factor revealing a vertical position in phase H · P; a horizontal vertical position in phase V · P; a horizontal veltical position in phase Rel.; a horizontal vertical position in phase P · H; then a vertical position in phase T · B, respectively as their essectial factors..Fourth, this time, it was the angular factor which showed as specifically the shoulder hoint and hip joint in phase H · P; the hip joint in phase V · P; the shoulder joint and hip joint in phase Rel.; the neck joint and hip joint in phase P · H; and, then differences of flexion and extention in the shoulder joint, hip joint, and knee joint phase T · B.To summarize the foregoing status, a retardness of the shoulder joint and the deflexion of the hip joint enabled a motion with composure incurring a long duration in phase H · S to phase H · P; a swing motion was taken by a great circle exercise, laying out the body in phase H · P to phase V · P; the lower legs were lifted up by using the physical reaction to take consumption of a fast time in phase V · P to phase Rel; and, it became a very decisive factor for the motion whether to succeed by taking the bar after fast revoution with a tuck posture in a short revoltionary radius or fail without doing so.

자연과학편 : 슬관절 굴곡 및 신전근의 피로에 따른 태권도 선수 하지근 동원 형태의 변화

박광동(KwangDongPark) 한국체육학회 2007 한국체육학회지 Vol.46 No.6

이 연구는 슬관절 근피로 유발 전후 태권도 앞차기 시 주변 근군의 동원 형태의 변화를 알아보기 위해 태권도 전공남자 대학생 7명과 태권도 비전공 대학생 7명을 비교집단으로 하였다. 피험자간 EMG 비교를 위한 표준화 작업을 위한 사전실험과 본 실험의 두 단계로 실시되었다. 등속성 근력 측정 장비를 이용하여 각속도 180°/sec에서 최대신전, 굴곡하는 동작을 연속해 50회씩 10분의 간격을 두고 3회 실시하는 knee flexor and extension fatigue test 방식으로 근피로를 유발하였다. EMG를 통해 근 활성도를 측정하였으며, 측정부위는 비복근, 전경골근, 복직근, 복사근, 대퇴직근, 외측광근, 내측광근, 대퇴이두근이었다. 국면 구분을 위해 촬영속도 100 frames/sec으로 촬영한 결과 첫째, 앞차기 수행시간은 전공집단에서 빨랐으며, 이에 대해 제 1국면과 제 2국면의 영향이 큰 것으로 나타났다. 둘째, 앞 차기와 관련한 근육 중 기여도는 대퇴직근과 복직근이 높은 것으로 나타났으며, 피로유발 후 복사근과 대퇴이두근이 추가 동원되는 경향을 보였다. 결존적으로 근피로는 태권도 앞차기 시 근육 동원 형태의 변화를 야기할 수 있으나, 제한적이며, 이를 일반화하기 위한 추가적 연구가 요구된다. The purpose of this research is to investigate the effects of muscular fatigue on alternations of leg muscle recruitments in Taekwondo players. 7 Taekowndo majored college students and 7 normal in this study volunteerly. Each subject was tested in the sitting position and made to perform 50 consecutive right knee extension and flexion at interval of 10 min between each series and then fartigue rate were determined EMG were completed on gastrocnemius tibialis anterior, rectus abdominis muscle, oblique muscle of abdomen, rectus femoris, vastus lateralis, vastus medialis, musculus biceps femoris. Video analysis with l00frames/sec camera were used to record the Taekwondo front kick motion to define phases. The duration of front kick were faster significantly in TAE compared to CON and the dura社on were influenced by phase 1 and 2. Rectus femoris and rectus abdominis muscle were most strongly firing muscle during Taekwondo front kick and oblique muscle of abdomen and musculus biceps femoris were additionally recruited in CON during phase 1. In conclusion, muscular fatigue can altemat muscle recruitrnents during Taekwondo front kick, however to generalize these results, further study were needed.

자연과학편 : 우슈(武術) 선풍각(旋風脚) 540° 발구름 동작의 지면반력 분석

강영석(YoungSeokKang),박광동(KwangDongPark) 한국체육학회 2007 한국체육학회지 Vol.46 No.6

이 연구는 우슈 종목의 투로 선수들의 고난도 도약 동작 중 선풍각 동작의 540°B난이도에 해당하는 기술 중 발구름 동작을 연구하여 지면반력기를 통하여 국가대표를 포함한 전국대회 3위 이내의 경력의 8년 이상의 우수한 선수들의 동작수행에 대한 기술적 특징들을 찾아내고 운동역학적 요인들을 분석함으로써 다음과 같은 결과를 얻었다. 이 연구의 결과를 종합해 보면 우슈 선풍각 540°를 완전하게 수행하기 위해서는 오른발의 압력중심점을 전족에 극대화 하여 발구름 시 지면을 짧은 발구름 시간으로 수직충격력과 지면반회전력을 크게 증가시켜 운동 진행방향으로 운동량을 증가시킴으로써 수직상방향으로 신체중심을 높이 투사시키는 것이 바람직한 것으로 나타났다. This Study has researched the take-off motion which is in the techniques applicable to 540°B-difficult degree of whirlwind kick among the high degree-hardship jumping actions of the Touro athletes in the Wushu event, and it found out through the force platform, the technical characters regarding to the motion performances of the excellent athletes who maintain the career within the 3rd ranking in the national athletic meeting for more than 8 years, including the athlete of the national team, and the following result has been obtained by means of analysis on the biomechanical factors. In synthesizing the result of this Study, in order to accomplish the Wu-shu whirlwind kick with tlie 540° perfectly, it should maximize the Center Of Pressure (COP) of right foot to the forefoot, and also by greatly increase the vertical impulsive force and ground anti-rotative force owing to its shorter take-off time at the ground surface when take-off, therefore it appeared as desirable to throw the center of body highly to the vertical upper direction by increase the momentum toward its motion proceeding direction.

특수체육 : 수영훈련이 뇌성마비 청소년의 혈장 LDH 동위효소와 CPK 농도에 미치는 영향

김미영(MiYoungKim),박광동(KwangDongPark) 한국체육학회 2005 한국체육학회지 Vol.44 No.4

The objective of this research is to find out the effect of the plasma LDH isoenzyme and CPK concentration related variances before and after 16 weeks' swimming exercise the high school students with cerebral palsy. The swimming was done 60 minutes per day and 5 times for 16 weeks. Warming up for the exercise test was done at the speed of 3.2㎞/h, on the degree of 3%, with a three minutes exercise and a three minutes rest. According the subjects' performance, the exercise test was done. The females were tested at the 3.2~4.0㎞/h speed and on the degree of 3% during the first 25 minutes and at the 4.0~5.6㎞/h speed with the degree of 3∼5% until all out. The males were tested at the 3.2~5.6㎞/h with a degree of 3% for the first 25 minutes and at the 4.0~5.6㎞/h with degree of 3∼9% until all out.The results of the tests are as follows.1) We can identify higher concentration of plasma LDH1 after exercise than before as well as the similar statistical difference. On the other hand, higher concentration of DHL2 is recognized after exercise than before. Both concentration of LDH3 and LDH4 have similar higher value after exercise. In case of LDH5, we can get higher value after exercise than before, moreover, only female's values has similar difference.2) The concentration of plasma CPK have higher value after exercise than before, however, has similar statistical difference.With above results, we can conclude that swimming exercise for 16 weeks cause very positive effects. However, we also realize the necessity for improving cerebral palsied adolescents physically handicapped property by keeping excercise and increasing exercise load because their exercise ability may be drastically reduced.

운동역학 : 쇼트트랙 스피드 스케이팅의 스케이트 반력 변화에 따른 특성 분석

전명규(MyungKyuJun),박광동(KwangDongPark),백진호(JinHoBack) 한국체육학회 2001 한국체육학회지 Vol.40 No.2

본 연구는 쇼트트랙 스피드 스케이팅 국가대표급 여자 선수 4명을 대상으로, 직선주로 활주 시 왼발 스케이트 반력의 특성을 분석하고, 이러한 전문적인 기술의 특성을 규명하여 우수선수들의 훈련지도에 기초자료로 제공함에 그 목적이 있다. 이에 직선주로의 왼발 스케이트의 활주와 푸시-오프동작에서 스케이트의 앞·뒤 로드셀에 작용되는 일축방향의 힘과 기준좌표의 수직 ·수평성분의 힘을 분석하였다. 스케이트 반력분석을 통하여 얻은 변인들의 상대비교와 논의를 통해 다음의 결론을 도출하였다.1. 직선주로 활주 시 브레이드에 작용되는 반력은 오른발이 빙면에서 이탈되는 시기와 왼발의 푸시-오프 직후에서 최대값이 나타났으며, 최대값의 범위는 0.87∼1.45b.w.이며, 평균반력은 1.1b.w.로 나타났다.2. 브레이드의 앞쪽 로드셀에서 측정된 반력은 푸시-오프에서 0.59∼0.99b.w.의 최대값이 나타났고, 뒤쪽 로드셀에서 측정된 반력은 프레이트 활주 직후 왼발이 기울어지기 직전에서 0.37∼0.55b.w.의 최대값이 나타났다.3. 브레이드에 작용되는 힘의 성분에서, 수직반력은 수평반력에 비해 크게 나타났으며, 수직반력은 플래이트 활주 직후 왼발이 기울어지기 직전과 푸시-오프 구간에서 0.24∼0.78b.w.의 크기로 나타났고, 수평반력은 푸시-오프 시점의 전·후에서 0.11∼0.41b.w.의 크기로 나타났다. The purpose of this study was to examine the kinetical characteristics of skating by left foot in straight track of reaction force changes acted on skate in straight in short track skating, to grope for the better skating techniques, and to give the basic data for training guidances on highly skilled skaters. In this study, 4 nationally ranked female short track speed skaters were employed as the subjects.Therefore, based upon comparative analysis from variables from reaction forces analysis, the following conclusions are drawn,1. In straight track, the maximum reaction force act on blade of skate indicated the moment of right foot take off and left foot push off and ranged from 0.87b.w. to 1.45b.w.. And reaction forces averaged 1.1b.w.2. Maximum reaction forces measured from the load cell attaching in front of the blade ranged from 0.59b.w. to 0.99b.w. at push off and maximum reaction forces from the rear blade ranged 0.37∼0.55b.w. just after the plate gliding.3. Vertical reaction force acting on blades was higher than horizontal force. Vertical reaction force ranged 0.24∼0.78b.w. at plate gliding and push off phase and horizontal velocity ranged 0.11∼0.41b.w. at the before and after push off moment.