• 한국운동역학회지
• /
• 제21권2호
• /
• pp.153-159
• /
• 2011

The purpose of this study was to develop an innovative training model and method to improve the posture and motion, while pulling up during weight lifting by evaluating the problems of Korean weight lifters performing this motion. To investigate the effectiveness of the new training method substitute members of the Korean national weight lifting team performed both the original pull up technique and new pulling training technique while kinetics and kinematics were recorded. For this study, the first phase of the new training method is more appropriate than the original training with the pull up drop slow deadlift to the knee joint. For the second phase, the new training motion is deemed to be more effective than the current box deadlift motion. Also, this new motion corrects the posture as there is more anterior hip joint motion(about 10 cm) and the knee flexes to about 120 degrees. For the third phase, starting about 10cm above the knee the box snatch high pull up is identified as a more suitable training method. For the forth phase, the box top snatch method is judged to be a more effective training method than the original top snatch training method.

• 한국운동역학회지
• /
• 제24권1호
• /
• pp.67-74
• /
• 2014

This study researched into the left-right inclination of the rear foot at the lower limb joints, knee joint angle, angular velocity of the knee joint, angular acceleration and the max. Based on the analysis of kinematics according to the changes in the height of step box (6, 8, 10 inches) during step aerobics of female college students majoring in physical education. The findings of this study are as follows: Then angle of the knee joint decreased as the height of the step box increased the min. Angle was measured right before the right foot was on the step box, and the angle tended to decrease as the step box get heightened. The left-right inclination of the rearfoot angle according to the height of step box increased as the height increased. In the 'pull-up' stage during which the weight was loaded on the right foot the angle increased, while in the right foot stepping stage during which the right foot was on the ground, the left-right inclination of the rearfoot angle increased as the height of the step box increased. The angular velocity of the knee joint according to the height of step box started increasing when the right foot initially stepped on the step box and during the initial stepping section, the angular velocity decreased as the height of step box increased. The changes in angular acceleration of the knee joint according to the height of step box increased as the height of step box increased.

• 한국임상수의학회지
• /
• 제34권5호
• /
• pp.318-324
• /
• 2017

The objective of this study was to establish kinematic reference ranges for the femorotibial (FT) joint and the patellofemoral (PF) joint in healthy small-breed dogs by measuring 3D kinematics at the walk. Single-plane fluoroscopy was used to image the stifle joints of five healthy beagle dogs while the dogs were walking. 3D bone models of the femur, patella, and tibia were reconstructed by computed tomography scanning of the beagle dogs' hind limbs. The shape-matching technique was used to measure kinematic data from the fluoroscopic images and the 3D bone models. The cranial translation of the tibia during walking was inversely proportional to the FT joint flexion. There were significant correlations between the patellar motion and the tibial motion. The FT joint flexion had a strong correlation with the patellar proximodistal translation and flexion. Additionally, the tibial mediolateral translation had a strong correlation with the patellar shift and tilt. In this study, normal in vivo 3D FT joint and PF joint kinematics were demonstrated, and the average kinematic parameters were determined in walking beagle dogs.

• 한국전문물리치료학회지
• /
• 제25권3호
• /
• pp.19-26
• /
• 2018

Background: Genu varum is also known as bow leg. It is a deformity wherein there is lateral bowing of the legs at the knee. it does give rise to pain, and persistent bowing can often give rise to discomfort in knees, hips and ankles. Objects: This study investigated the effect of narrow squats on the knee joint during a gait and distance between the knees of person with genu varum. Methods: This study analyzed 23 patient with genu varum that grade III, 12 narrow squat group and 11 genenal squat group in motion analysis laboratory. The subjects of experiment took gait before and after intervention, the range of joint motion, moment of knee joint adduction, power, distance of the knees were measured. And in order to make an analysis between groups, an paiered t-test and independent t-test was carried out. For statistical significance testing, it was decided that significance level ${\alpha}$ be .05. Results: It was shown that the group of narrow squat exercise significantly decreased in distance of knees (p<.05),In moment of adduction of knee joint, it was shown to significantly decrease in two groups (p<.05), was significantly decreased in adduction, abduction, and rotation (p<.05). In relation of peak-knee adduction moment and valgus angle, there was significant decrease in narrow squat group (p<.05). Conclusion: When the above result of study were examined, a narrow squat exercise given to the genu varum patients significantly decreased the distance between the knees, range of knee adduction and abduction, knee adduction moment, knee power. And stability gains through the decrease of excursion of knee medial part be effective for the correction of genu varum deformation.

• 한국안전학회지
• /
• 제23권1호
• /
• pp.35-45
• /
• 2008

This study was performed to compare the kinematics among three different safety shoes(type 1: ergonomically designed and high quality shoes, 2: curved and cushioned safety shoes, and 3: regular safety shoes) and to find the effect of insole during walking. Ten healthy subjects were recruited for this study. The range of motion of knee and ankle joint, angle of rear foot and angle of heel contact were measured using a three dimensional motion analysis system. In the second peak, the angle of heel contact showed statistically significant difference between safety shoes and insole, however, there was no statistical significance among three different safety shoes. The angle of ankle increased significantly at initial contact, first peak, the second peak and the toe off phase compared with type 1 and 2 safety shoes, and the angle of ankle showed statistically significant difference between with and without applying the insole. During the first peak, the second peak and the toe off phase, the angle of knee was statistical significance between safety shoes and insole. In heel contact, the angles of Achilles' tendon showed statistically significant difference between safety shoes and insole. The rear foot angles showed statistically significant difference between safety shoes and insole during heel contact and early heel contact. These results suggest that the type 1 safety shoes were superior to others in the statistics, and applying insole could be a possible method to prevent fatigue of lower extremity and musculoskeletal disorders. Further studies are needed to find the effect of ergonomically designed safety shoes and insole on practical value in prevention of musculoskeletal disorder, fatigue and satisfaction of workers.

• 한국운동역학회지
• /
• 제27권1호
• /
• pp.9-18
• /
• 2017

Objective: The purpose of this study was to identify kinematic variables that govern successful performance and judges' scores and to establish correlative relationships among those of Yurchenko layout with a full twist in female vaults. Method: Four video cameras with sampling rate of 60 Hz collected 32 motion data of Yurchenko vaults from twenty-two female participants (age: $18.6{\pm}3.6years$, height: $153.0{\pm}6.5cm$, mass: $44.7{\pm}7.3kg$) during national competition. Posting processing and calculations of kinematic variables were performed in Kwon 3D XP and $Matlab^{(R)}$ programs. Correlation and regression analyses were applied to find the relationships between the obtained scores and kinematic variables. Deterministic model (Hay & Reid, 1988) was used to investigate the strength of correlative relationships among kinematic variables. Results: The obtained scores from the judges' decision were mainly affected by post-flight peak height, horse contact time, knee angle at landing, and horse takeoff angle. Strong blocking during horse contact was required to get successful performance and obtain high scores. Modified deterministic model showed that round-off entrance and takeoff angles and resultant velocity of the center of mass (CM) during the roundoff phase were the starting variables affecting performance in the following kinematics. Knee angle at landing, a highly influential variable on the obtained point, was only determined by judges' decision without significant correlative relationship with previous kinematic variables. Conclusion: The obtained scores highly depended on kinematic variables of post-flight and horse contact phases that were affected by those from the previous phases including round-off postures and resultant velocity of the body center of mass.

• 한국운동역학회지
• /
• 제14권1호
• /
• pp.145-160
• /
• 2004

The purposes of this study to provide quantitative data in necessary to advance techniques kinematic analysis of Cucarachas which is an action of Rumba. Then, this study is performed on 5 female players who have won within the third prize at a national athletic meeting. When whole foot reached to floor, Displacement of right-left hip joint (until $E1{\sim}E3$ average moved 15.15cm)is found at right-left direction since the hip joint is turned to right back. On the other side, large displacement is shown because Rumba Cucaracha Movement is expressed by maximum shift of hip joint to right and left direction. Displacement of right hip joint(E3$57.40{\pm}7.46$) is found in front and in rear direction since hip joint is moved in rear and in front to turn the hip joint. It may be stated that this is ideal displacement expressed by movement of whole body with artistic poise and presentation because role of hip joint is very important in technical and artistic side. Angle of right shoulder joint E2($105.44{\pm}9.64$) is got wider. It may be stated that player shifts up and abduct elbow joint to right since center of gravity of player is exceedingly shifted to right in this motion of Cucarachas. On the other hand, since this motion is abducted right elbow and shrunk external abdominal oblique to him center of body to left front of hip joint, the angle becomes narrow. It is shown that angle of knee in right knee joint E4($75.44{\pm}2.61$) is large since right leg and hip joint is turned by foot using reaction of ground and so center of body is shifted to left. Large angle of ankle E4($134.40{\pm}10.50$) in Cucaracha Movement is shown by the action of twist force using narrow part of foot and compression force against ground with adduction speed of arm. The various kinematic analyses associated with motions of dance sport have not been sufficiently peformed so far, and thus a number of research projects for dance sport should be proposed and performed to be continuous.

• 한국체육학회지인문사회과학편
• /
• 제53권2호
• /
• pp.531-540
• /
• 2014

본 연구는 두 종류의 공기주입식 카약 보트의 성능 비교와 함께 선수들의 카약 전방 스트로크 동작의 차이점을 비교 분석하여 보다 효율적이고 안전한 카약 보트를 찾는 데 목적이 있다. 이를 위해 대한 체육회 소속 K 고등학교 엘리트 남자 선수 5명이 연구에 참여하였으며, K고 실내 수영장에서 실험을 실시하였다. 보트의 성능 평가를 위해 보트 속도, 보트 좌우 흔들림 각도 차이, 보트의 회전 평균 각속도를 산출하였으며 선수의 수행력 차이를 분석하기 위해 몸통의 회전 가동범위, 무릎 관절의 굴곡-신전 가동범위, 몸통의 최대 회전 각속도, 무릎관절의 최대 신전 각속도, 상하지 근육의 활성도를 산출하였다. 연구 결과 선수들의 수행력 평가 변인에서는 통계적으로 유의한 수치를 보이지 않았다. 보트의 성능 평가 변인에서는 보트의 속도에서 B보트가 통계적으로 유의하게 빨랐으며 다른 변인들은 통계적으로 유의한 차이를 보이지 않았다. 결국 길이가 상대적으로 길고 폭이 상대적으로 좁은 B보트는 A보트와 비교했을 때 비슷한 안전성을 갖고 있으면서 보다 효율성을 나타내었다.

• 한국운동역학회지
• /
• 제28권4호
• /
• pp.199-205
• /
• 2018

Objective: The purpose of this study was to examine the effect of increase in barbell weight on closely related variable to the anterior cruciate ligament (ACL) injury which are knee joint kinematics, joint load, joint moment, and maximum load attainment point during snatch of the weight lifting. Method: The subjects of the study were 10 male Korean national weight lifting athletes (69 kg 5, 77 kg 5; age: $21.80{\pm}3.91yrs.$, height: $168.00{\pm}4.06cm$, weight: $75.00{\pm}4.02kg$, career: $7.8{\pm}3.99yrs.$, snatch records: $168{\pm}4.06kg$). The weight of the barbell during the snatch operation was set at 70%, 75% and 80% of the highest records for each subject studied. Results: The result obtained from the one-way repeated measure ANOVA are as follows: With increased barbell weight, the extension moment of the left knee joint was higher in the 80% condition than the 70% (p<.001). However, other variables were not statistically significant difference. According to the factor analysis of the variables related to maximum load attainment point of the ACL major injury variables, the first sub-factor was the internal shear force, the posterior shear force, the abduction moment, and the muscle activity of the VL. The second sub-factor was the extension moment of the knee joint, compressive force, adduction moment, and the third sub-factor was the muscle activity of BF. Conclusion: These results indicate that the possibility of ACL injury can be lowered when performing a stable snatch movement.

• The Journal of Korean Physical Therapy
• /
• 제25권6호
• /
• pp.379-385
• /
• 2013

Purpose: The purpose of this study is to compare kinematics on lower limbs between stair walking with high heel and barefoot in healthy adult women. Methods: 18 healthy adult women were recruited in this study. The subjects performed stair ascent and descent with high heels and barefoot. The experiment was conducted in random order and repeated three times for each stair walking with high heels and barefoot. The movements of lower limb joints were measured and analyzed using a three-dimensional analysis system. Results: The ankle, knee, and hip flexion angles on the sagittal plane exhibited statistically significant differences between stair ascent and descent with high heels and barefoot. The pelvic forward tilt angles showed statistically significant differences only during stair ascent. The ankle inversion, hip abduction and pelvic lateral tilt angles on the frontal plane showed statistically significant differences between stair walking with high heels and barefoot. On the transverse plane, the hip rotation angles showed statistically significant differences between the high-heeled and barefoot gait during stair ascent and descent. However, the pelvic rotation angles showed no statistically significant differences. Conclusion: Therefore, wearing high-heeled shoes during stair walking in daily life is considered to influence lower limb kinematics due to the high heel, and thus poses the risks of pain, and low stability and joint damage caused by changes in the movement of lower limb joints.