• 한국의류학회지
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• 제26권12호
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• pp.1739-1748
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• 2002

본 연구의 목적은 소방용 coverall의 디자인이 소방수들의 동작기능성에 어떤 영 향을 주는지에 관하여 고찰하여, 보다 기능적 인 coverall을 개발, 궁극적으로 작업자의 노동력을 향상시키고, 보다 안락한 환경 속에서 작업할 수 있도록 도와주는데에 있다. 미국 캔사스 지역의 전문 소방수를 대상으로, interview 및 video analysis를 통하여, 그들이 현재 사용하고 있는 current coverall의 동작기능면에서의 문제점을 조사, 분석한 후, 이를 바탕으로 prototype coverall을 개발하였다 prototype coverall의 동작기능성을 객관적으로 측정하기 위하여 10가지 실험동작(shoulder adduction/ abduction, shoulder flexion/extension, trunk flexion/extension(standing), hip flexion/extension(knee), hip flexion/extension(trunk), upper leg flexion, trunk lateral flexion, hip adduction, trunk flexion/ extension(sitting), upper leg flexion)을 선택하여 이의 관절각도(range-of-motion)를 Leighton flexometer, goniometer, computer-aided method를 이용하여 측정하였으며, 착용자의 주관적 평가를 위하여서는 23 항목의 wearer acceptability scale를 사용하였다. ANOVA(Analysis of Variance)와 LSD(Least Significant Difference)를 이용한 통계처리 결과, prototype coverall이 current coverall에 비해 동작기능성 (특히 crotch, torso, hip movement)에 있어서 우수함을 보이고 있다.

• 한국전문물리치료학회지
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• 제10권3호
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• pp.71-79
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• 2003

Manual tracking is an experimental paradigm that can be used to study information processing in continuous movements involving accurate, ongoing control of motor performance. The purpose of this study was to identify the effects of knee tracking training, using the paretic side, on gait in stroke patients. Nine patients with hemiplegia participated in the study. The timed 10 m gait speed test and tracking test were administrated. The tracking test was composed with ranges of $-20^{\circ}$ to $20^{\circ}$ and $0^{\circ}$ to $60^{\circ}$. The tracking training consisted of five times every week for 4 weeks. The data were analyzed by non-parametric paired sign test of Wilcoxon. The flexion/extension error of the tracking test was significantly reduced on the paretic side, while the nonparetic side was not statistically significant. The transfer of the skill to the functional activity was shown in the significant improvement at timed 10 m gait speed test. This study shows that individuals with chronic who have impaired knee movement can be trained to improve their knee control through intensive practice at a knee movement tracking task and that the skill learned from such training is transfered to a more functional gait speed.

• 한국운동역학회지
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• 제19권4호
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• pp.697-705
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• 2009

본 연구의 목적은 여성고령자들에 있어 젊은 여성과 비교해 Sit-to-Walk동작 시 낙상의 간접적인 요인이 될 수 있는 역학적 에너지를 비교분석 하는 것이다. 여성고령자 그룹 10명과 젊은 여성 그룹 10명이 본 연구를 위해서 참여하였고, 적외선 카메라와 두 대의 지면반력기를 통하여 역학적 에너지를 분석한 결과는 다음과 같다. 근 파워는 각속도와 근 모멘트의 변화에 따라 고관절의 무릎 및 고관절의 신전 국면시 두 그룹 모두 낮은 음의 일률을 보였고, 특히 고령자그룹에 더 낯은 음의 일률을 보였다. 역학적 에너지 일량에 있어서도 무릎관절과 고관절은 무릎 및 고관절 신전 국면에서 두 그룹 모두 음의 일량을 보였고, 특히 고관절은 전체국면에서 고령자 그룹에 있어 더 낮은 음의 일량을 보였다. 이러한 결과는 STW동작 시 고관절 대퇴근의 약화로 인한 에너지 손실(dissipation)은 고령자들의 낙상의 위험요소를 간접적으로 보여주는 것이라 여겨진다.

• 대한정형도수물리치료학회지
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• 제15권2호
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• pp.63-68
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• 2009

Purpose : The purpose of this study was to investigate the effect of tensor fasciae latae length on the rotation of pelvis during one leg stance. Methods : 41 healthy adults participated in this study. The movement of the pelvis and trunk was measured using 3-dimensional motion analyzer, during one leg stance. The movement of the pelvis and trunk was collected lateral shift, rotation, side bending, and flexion-extension. Tensor fasciae latae length of subjects was measured in sidelying positon with neutral position of hip joint and flexion $90^{\circ}$ of knee. Also, the range of motion of hip exteral and interal rotaion were measured in prone position wih lexion $90^{\circ}$ of knee. The subjects were separated 2 groups that more pelvic rotation group(n=15) and less pelvic rotation group(n=15) according to the degree of pelvic rotation. Results : The more pelvic rotation group was showed significantly higher in the ROM of hip external rotation than less pelvic rotation group(p<0.05). The difference of tensor fasciae latae length not showed significant difference between groups. During one leg stance, The movement of the shifting and flexion-extension of trunk and pelvis were not showed significant difference. But the side bending and the rotation of pelvis and trunk showed significant difference between groups. Conclusion : The difference of tensor fasciae latae length not showed significantly in more pelvic rotation group and less pelvic rotation group. But, this study suggests that the pelvis instability brings the instability of the trunk during one leg stance.

• 한국운동역학회지
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• 제16권1호
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• pp.31-41
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• 2006

The primary purpose of a TKA is to restore normal knee function Therefore, ideally, a TKA should: (a) maintain the natural leverage of the knee joint muscles to ensure generating adequate knee muscle moments to accomplish daily tasks such as rising from climbing stairs; (b) provide adequate knee joint stability. A 16-channel MyoResearch XP EMG system was used to collect the differential input surface electromyography signals VM, VL, RF, BF, ST during climbing/descending stair tests. A Peak Motion Measurement System was used to collect the kinematic and kinetic data. AKIN-COM Ill isokinetic dynamometer was used for EMG of VM, VL, RF, BF and ST during maximal voluntary contraction. I Quadriceps EMG results for the VM of the passed 1year group limb demonstrated significant less RMS EMG than that of the passed 3year group limb $60^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The VL of the passed 1year group limb also demonstrated significants less RMS EMG than that of the passed 3year group limb from $60^{\circ}-45^{\circ}$ of knee flexion(p<0.05). Similar to the VM and VL, the RF of the passed 1year group limb showed less RMS EMG than that of the passed 3year group limb from $60^{\circ}-30^{\circ}$ do knee flexion(p<0.05). Hamstring EMG results for the BF of the passed 1year group limb demonstrated less RMS EMG than that of the passed 3year group limb from $75^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The passed 1year group limb tended to have less ADD displacement(p<0.071) than that of the passed 3year group limb. There was no significant difference of the ABD displacement between the passed 1year group and the passed 3year group limbs(p<0.73). The passed 3year group used compensatory adaptation movement strategies to compensate for the strength deficit of passed 3year group limbs. The passed 3year group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. The passe 3year group limb might have an unstable knee joint in the medio-Iateral direction during the climbing/descending by showing a tendency of more ADD displacement and greater hamming co-activation EMG than the passed 1year group limbs. The TKA design was not able to help the knee joint to produce adequate knee extension moment with less quadriceps muscle effort. I think that old man needs continuous exercise for muscle strength.

• 한국운동역학회지
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• 제18권1호
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• pp.203-212
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• 2008

본 연구의 목적은 자진모리장단에 맞추어 3단 디딤새동작의 적합한 모델을 제시하고 이상적인 발 디딤새 동작수행을 위한 자료제공을 목적으로 하였다. 신체중심의 위치변화는 발을 내딛는 순간 신체중심의 높이를 낮추고 발의교차 전진시 전방으로 향하는 직선운동을 수직운동으로 전환하여 동작의 안정성을 유지하며, 좌 우 흔들림 없이 이동하는 것으로 나타났다. 신체중심에 대한 속도변화는 수평방향으로 발을 딛는 순간 신체유동을 작게 하고 전방으로 급격한 이동을 통제하여 안정된 동작을 취하고, 슬관절과 족관절을 수직으로 들어 올려 종골이 지면에 닿을 때 무게중심의 속도가 수평방향으로 빠르게 전진하지 못하게 하는 것으로 나타났다. 관절의 각도변화는 하퇴의 과신전을 막기 위해 고관절은 신전시키고 슬관절은 굴곡 시켜 동작의 안정성을 확보하여 굴곡과 신전이 원활히 이루어지며, 족관절은 중족 에서 발바닥 전체로 무게중심이동시 좌측 발은 배측굴곡을 이룰 때 안정적인 동작이 이루어지는 것으로 나타났다.

• 한국운동역학회지
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• 제25권3호
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• pp.311-322
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• 2015

Objective : The purpose of this study was to investigate the effects of landing height and knee joint muscle fatigue on the movement of the lower extremity during cutting after landing. Method : Subjects included 29 adults (age: $20.83{\pm}1.56years$, height: $172.42{\pm}9.51cm$, weight: $65.07{\pm}10.18kg$). The subjects were asked to stand on their dominant lower limb on jump stands that were 30 and 40 cm in height and jump from each stand to land with the dominant lower limb on a force plate making a side step cutting move at a $45^{\circ}$ angle with the non-dominant lower limb. The fatigue level at 30% of the knee extension peak torque using an isokinetic dynamometer. Results : The results showed that the difference of landing height increased maximum range of motion and angular velocity of hip, knee, and ankle joints in the sagittal plane, and in the angular velocity of motion of the hip joint in the sagittal plane. The maximum range of motion of the knee joint in the sagittal plane and the frontal plane decreased on landing from both heights after the fatigue exercise. The angular velocity of the hip joint in the sagittal plane, and the maximum range of motion of the hip joint in the transverse plane decreased for both landing heights after the fatigue exercise. The angular velocity of the hip joint in the frontal plane decreased for the 30 cm landing height after the fatigue exercise. On the other hand, the angular velocity and maximum range of motion of the ankle joint in the sagittal plane for both landing heights, and the angular velocity and maximum range of motion of the ankle joint in the frontal plane increased on landing from the 40 cm height after the fatigue exercise. Conclusion : Different landing heights of 30 and 40 cm and 30% fatigue of peak torque of knee extensor found a forefoot and stiff landing strategy, when cutting after landing. These results might be due to decline in the shock absorption capability of the knee joint and the movement capability related to cutting while increasing the contribution of the ankle joint, which may cause increased ankle joint injuries.

• 한국운동역학회지
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• 제19권2호
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• pp.369-377
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• 2009

The purpose of this study was to determine the relationship between different soccer cleat designs and knee joint moments. Twelve physically active males (mean(SD): age: 26.4(6.2)yrs; height: 176.4(4.1)cm; mass: 74.0 (7.4)kg) were recruited Kinematic and force plate data were collected for all subjects during normal running and a $45^{\circ}$ cutting maneuver, called a v-cut. Both motions were performed at $4.0{\pm}0.2\;m/s$ on infilled artificial turf with three pairs of soccer cleats of different sole plate designs, and one pair of neutral running shoes. Inverse dynamics were used to calculate three dimensional knee joint moments, with repeated measures ANOVA and post hoc paired Student's t-test used to determine significance between shoe conditions. Significant differences were found in the extension moments of the knee for running trials, and for external rotation and adduction moments in the v-cutting trials. Knee moments were greater in v-cut than running, and the traditional soccer cleats (Copa Mondial and World Cup) tended to result in greater knee moments than the Nova runner or TRX soccer cleat. Cleat design was found to influence 3-dimensional knee moments in a v-cut maneuver. In the translational traction test, there were significant differences between all conditions. In the rotational traction test, friction with soccer shoes were greater than friction with running shoes. However, no differences were found between soccer shoes. Higher moments may lead to increased loads and stresses on knee joint structures, and thus, greater injury rates.

• Journal of Mechanical Science and Technology
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• 제19권10호
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• pp.1919-1931
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• 2005

Human joint motion can be kinematically described in three planes, typically the frontal, sagittal, and transverse, and related to experimentally measured data. The selection of reference systems is a prerequisite for accurate kinematic analysis and resulting development of the equations of motion. Moreover, the development of analysis techniques for the minimization of errors, due to skin movement or body deformation, during experiments involving human locomotion is a critically important step, without which accurate results in this type of experiment are an impossibility. The traditional kinematic analysis method is the Angular-based method (ABM), which utilizes the Euler angle or the Bryant angle. However, this analysis method tends to increase cumulative errors due to skin movement. Therefore, the objective of this study was to propose a new kinematic analysis method, Position-based method (PBM), which directly applies position displacement data to represent locomotion. The PBM presented here was designed to minimize cumulative errors via considerations of angle changes and translational motion between markers occurring due to skin movements. In order to verify the efficacy and accuracy of the developed PBM, the mean value of joint dislocation at the knee during one gait cycle and the pattern of three dimensional translation motion of the tibiofemoral joint at the knee, in both flexion and extension, were accessed via ABM and via new method, PBM, with a Local Reference system (LRS) and Segmental Reference system (SRS), and then the data were compared between the two techniques. Our results indicate that the proposed PBM resulted in improved accuracy in terms of motion analysis, as compared to ABM, with the LRS and SRS.

• 한국운동역학회지
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• 제28권4호
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• pp.199-205
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• 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.