• 제목/요약/키워드: Movements of the center of pressure

검색결과 51건 처리시간 0.028초

골프드라이빙 스트로크시 역학적 분석 (Mechanical Analysis of golf driving stroke motion)

  • 박광동
    • 한국운동역학회지
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    • 제12권1호
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    • pp.205-219
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    • 2002
  • This research seeks to identify the plantar pressure distribution graph and change in force in connection with effective golf drive strokes and thus to help ordinary golfers have appropriate understanding on the moving of the center of weight and learn desirable drive swing movements. To this end, we conducted surveys on five excellent golfers to analyze the plantar pressure applied when performing golf drive strokes, and suggested dynamic variables quantitatively. 1) Our research presents the desire movements as follows. For the time change in connection with the whole movement, as a golfer raises the club head horizontally low above ground from the address to the top swing, he makes a semicircle using the left elbow joint and shaft and slowly turns his body, thus lengthening the time. And, as the golfer twists the right waist from the middle swing to the impact with the head taking address movement, and does a quick movement, thus shortening the time. 2) For the change in pressure distribution by phase, to strike a strong shot with his weight imposed from the middle swing to the impact, a golfer uses centrifugal force, fixes his left foot, and makes impact. This showed greater pressure distribution on the left sole than on the right sole. 3) For the force distribution graph by phase, the force in the sole from the address to halfway swing movements is distributed to the left foot with 46% and to the right foot with 54%. And, with the starting of down swing, as the weight shifts to the left foot, the force is distributed to the left sole with 58%. Thus, during the impact and follow through movements, it is desirable for a golfer to allow his left foot to take the weight with the right foot balancing the body. 4) The maximum pressure distribution and average of the maximum force in connection with the whole movement changed as the left (foot) and right (foot) supported opposing force, and the maximum pressure distribution also showed much greater on the left sole.

의복압 분석에 따른 중년 여성의 재킷비교평가 연구 (Comparative Evaluation of Jacket for Middle-aged Women according to Clothing Pressure Analysis)

  • 이영숙;박은주;서추연
    • 한국의류학회지
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    • 제27권5호
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    • pp.485-495
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    • 2003
  • This study was to compare and analyze the clothing pressure according to arms movements of 4 brands jacket for middle-aged women group by measuring clothing pressure of each brand. The results were as follows: 1. According to the analysis of jackets of 4 brands, in general, jacket C had the largest ease amount. while jacket A had a large ease amount in waist, hip areas compared with bust area. Also jacket B had a small ease amount in bust, waist areas and jacket D had a small ease amount in hip areas. Therefore the ease amount is different between each brand, each size even though jacket designs are similar. 2. It was found that clothing pressure was affected by arm movements than jackets. Since this study was limited to the arm movement for motion variation, it was recognized that a significant difference among each jacket and each movement at shoulder, waist parts existed with relation to this motion. 3. Parts showing a significant difference among each size were bust point, abdomen point, center back point of abdomen level, angulus superior scapulae point and center back point of waist level. Also clothing pressure of size B91 was bigger than size B88 except Center back point of waist level. 4. Clothing pressure in shoulder point, front armpit point, back armpit point, upper arm point areas increased as the angle of the arms movement increased. Also, individual variation of clothing pressure in front armpit point, back armpit point, armpit point and upper arm point was large, and clothing pressure in abdomen point was high in M5(sitting posture).

무릎스쿼트 운동과 스쿼트 운동 자세에 따른 뇌졸중 환자의 균형 비교 연구 (A Study on the Balance of Stroke Patients According to Kneeling Squat Exercise and Standing Squat Exercise Positions)

  • 고관혁;김병조
    • 대한통합의학회지
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    • 제10권4호
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    • pp.1-9
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    • 2022
  • Purpose : The purpose of this research is to propose a more efficient exercising method by measuring and comparing the movement of center of pressure (COP) while hemiplegic stroke patients perform kneeling squat exercise and squat exercise. Methods : 17 hemiplegic stroke patients were instructed to perform kneeling squat exercises and squat exercises, and the research was designed as a cross-over study. For data collection, a pressure distribution measurement platform (PDM) was used to measure the movement area, length, speed, and distance from the center of the X-axis of center of pressure. The data was then analyzed through a paired t-test. Results : Kneeling squat exercises have been found to have a significantly smaller center of pressure movement area compared to that of squat exercise(p<.001), and the center of pressure movement length of kneeing squat exercise has also been found to be relatively shorter (p<.001). Moreover, kneeling squat exercises have been found to have a significantly slower center of pressure movement speed than squat exercise (p<.001), and kneeing squat exercise center of pressure movement distance from the center of the X-axis has been found to be significantly small (p<.001). Conclusion : Kneeling squat exercises have significantly decreased amounts of center of pressure movement area, distance, and speed compared to squat exercises. Also, the center of pressure movement distance from the center of the X-axis was relatively closer. This result seems to derive from patients performing their motions with wide base surfaces while being refrained from using unstable ankle joints during kneeing squat exercise. Therefore, it can be concluded that kneeing squat exercises show relatively balanced center of pressure movements between the paralyzed and non-paralyzed sides because kneeling squats show smaller shakes in the center of pressure.

정상인의 지면수평자보행에 대한 입각기 압력중심의 이동 (Movements of the Center of Pressure During Stance Phase in Free Level Walking of Normal Adults)

  • 김영호;양길태;문무성;박시복
    • 대한의용생체공학회:의공학회지
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    • 제20권5호
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    • pp.587-592
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    • 1999
  • 압력측정시스템은 입각기동안 동적압력분포를 성공적으로 측정할 수 있으나 하중수용기-중간입각기, 말기입각기-전유각기의 전환기들에 대해서는 운동분석시스템을 사용하지않고는 정확한 정의가 불가능하다. 따라서 저자들은 수평자유보행 시 압력중심의 이동을 이해하기 위해서 정상적인 발을 가진 20-30대 성인남자 78명을 대상으로 동작분석과발바닥 압력측정을 동시에 수행하였다. 결과로 하중반응기-중간입각기 전환시기의 발바닥 압력중심점은 후족부와 중족부의 경계선에서 앞쪽으로 1.9$\pm$1.5frame(32$\pm$24msec)에 위치하였으며 말기입각기-전유각기 전환시기에는 중족골두 최대 압력점의 앞쪽으로 2.3$\pm$2.0 frame(38$\pm$33msec)에 위치하였다. 정상수평보행에 있어서 최초접지 순간 압력중심은 전방으로 빠르게 이동하다가 바로 급속히 감소하여 하중반응기-중간입각기의 전환시기에는 작은 속도로 이동하였다. 압력중심의 이동속도는 그 후 다시 서서히 증가하다가 전체 보행주기의 25% 전후에서 서서히 감소하여 비교적 일정하다가 말기입각기-전유각기의 전환시점에서 다시 급격한 증가를 보였다. 족부질환과 보행특성을 판단하는데 있어서 압력중심의 이동궤적은 매우 유용한 인자가 될 것으로 기대된다. 본 연구를 통해서 압력측정시스템만으로는 정의할 수 없었던 두 전환기인 하중반응기-중간입각기, 말기입각기-전유각기를 결정할 수있게 되었다.

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Effects of Ankle and Hip Strategy Training on Improving the Center of Pressure Movements and Limits of Stability in Stroke Patients

  • Park, Shinjun;Park, Sunghyun;Kim, Yongyoun
    • 국제물리치료학회지
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    • 제10권3호
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    • pp.1823-1829
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    • 2019
  • Background: Stroke patients have leg muscle weakness and impaired balance resulting in compensatory changes. To restore balance in these patients, functional training using postural strategy is needed. Objective: To examine the effects of ankle and hip strategy training on the center of pressure (COP) movement and limits of stability (LOS) in standing posture in stroke patients. Design: The study was an assessor-blinded and randomized-controlled clinical trial. Methods: Thirty patients were randomly assigned to an ankle strategy training group and a ankle/ hip strategy training group. Patients in the ankle strategy training group underwent ankle strategy exercise for 30 min, and those in the ankle/ hip strategy training group underwent 15 min of ankle strategy exercise and 15 min of hip strategy exercise. Both groups underwent training thrice a week for four weeks. Forward, backward, paretic side, and non-paretic side COP movements and LOS were measured using BioRescue. Results: After the intervention, except for the backward area in the ankle strategy training group, the COP movement area and the LOS were significantly improved in both the groups. In addition, these improvements were significantly higher in ankle/ hip strategy training group than that in the ankle strategy training group. Conclusions: Ankle strategy training in addition to hip strategy training improves COP movement (forward-backward, paretic side area, and non-paretic side area) and LOS in stroke patients.

컴파운드 양궁의 팔로우 스루 동작과 사격 정확도의 상관관계 (Relationship of Follow-through Movements to Target Accuracy in Compound Archers)

  • Junkyung Song;Kitae Kim
    • 한국운동역학회지
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    • 제34권1호
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    • pp.34-44
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    • 2024
  • Objective: This study aimed to investigate how the movements occurring during the follow-through phase after releasing an arrow among elite compound archers, are associated with the arrow impact points on the target. Method: Nine elite archers performed consecutive compound archery shooting under conditions identical to actual competitions using their own bows and equipment. Motion capture system and force platform were utilized to record the changes in joint positions and center of pressure, respectively. Principal component analysis was employed to identify the patterns in which multidimensional joint positions and COP changes were organized with horizontal and vertical coordinates of arrow impact points. Subsequently, correlation analysis quantified the relationship between individual variables and the coordinates of arrow impacts on the target. Results: We found a common organizational pattern in which the two axes of the impact point coordinates were grouped into the first two principal components. The movements of the upper and lower limbs following release exhibited opposite patterns in the anterior-posterior axis, with significant correlations observed between the arrow impact points of the horizontal axis and the left shoulder, right elbow, left hip, and both knees. Additionally, the lateral movements induced by the reaction force upon arrow release showed significant associations with the vertical coordinates of the impact points. Particularly, the correlations between the movements of the left shoulder and elbow, as well as the bilateral hip and right knee, were consistently observed among all participants. Conclusion: These findings implied that the post-release movements could significantly influence the trajectory and impact points of the arrows in compound archery. We suggest that a consistent and controlled movement during the follow-through phase may be more beneficial for optimizing shooting accuracy and precision rather than minimizing movements.

새롭게 개발한 요천추 보조기의 과제 수행 중 척추의 고정효과와 복부압력 (Immobilization Effect and Abdominal Pressure of Newly-Developed Lumbosacral Spinal Orthosis during Task Performance)

  • 전경수;양희승;장수웅;신희동;이윤경;이영;이슬빛나;안동영;심우섭;조민;조규직;박동범;박관수
    • Clinical Pain
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    • 제19권2호
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    • pp.70-79
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    • 2020
  • Objective: We evaluated the efficacy of a newly-developed spinal orthoses (V-LSO) by comparing the stabilizing effect, abdominal pressure, and comfort of 3 different semirigid LSOs (classic LSO, V-LSO, and Cybertech®) during various body movements. Method: Thirty healthy volunteers (23~47 years, 24 males, 6 females) were selected. A dual inclinometer measured the range of motion (ROM) while the participants performed flexion/extension and lateral flexion of the lumbar spine with 3 LSOs. The LSO's pressure on the abdominal surface was measured using 9 pressure sensors while lying, sitting, standing, flexion/extension, lateral flexion, axial rotation, and lifting a box. Comfort and subjective immobilization were analyzed by a questionnaire. Results: V-LSO had a statistically significant effect on flexion over Cybertech®. No significant differences were noted during extension and lateral flexion between the 3 LSOs. The abdominal pressure showed no significant differences while supine. While sitting, standing, and lifting a box, the mean abdominal pressure for V-LSO were significantly higher than those for Cybertech®. During lumbar flexion, the mean abdominal pressures for classic LSO and V-LSO were significantly higher than that of Cybertech®. For extension, lateral flexion and axial rotation, the abdominal pressure for V-LSO was significantly higher than those of classic LSO and Cybertech®. In the subjective analysis, V-LSO and Cybertech® scored best for comfort. Conclusion: The V-LSO and Cybertech® were more comfortable than the classic LSO, and hence, may have improved compliance with decreased discomfort. V-LSO may be superior to the other LSOs in restricting lumbar movement and increasing intraabdominal pressure.

발목관절 근력과 관절위치감각, 그리고 균형능력에 미치는 고유수용성 신경근 촉진법 중재와 테이핑 중재 비교연구 (A Comparative Study of the Effects of Proprioceptive Neuromuscular Facilitation and Taping Interventions on Balance Ability, Joint Position Sense, and Ankle Joint Strength)

  • 김좌준;박세연
    • PNF and Movement
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    • 제16권1호
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    • pp.51-58
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    • 2018
  • Purpose: The aim of the present study was to investigate the effects of proprioceptive neuromuscular facilitation (PNF) and taping interventions on balance ability, joint position sense, and ankle joint strength. Methods: Thirty subjects who had experienced an ankle sprain within the previous 3 months participated in this study. The subjects were randomly assigned to a PNF group (n=15) or a taping group (n=15). Before and after the interventions, ankle dorsi-flexion and plantar-flexion strength, joint position error, and total center of pressure movements in one leg while in a standing position were measured. Results: Regardless of the group allocation, ankle dorsi-flexion and plantar-flexion strength significantly improved after the interventions (p<0.05). Compared to preintervention measurements, joint position errors were significantly reduced postintervention (p<0.05). The PNF intervention significantly decreased the total lateral movement of the center of pressure in the one leg standing condition (p<0.05). Conclusion: Both PNF and taping interventions improved joint position sense and ankle joint strength. In common with the findings of a previous study, the PNF intervention improved balance ability. Further study is required to investigate the effects of various PNF and taping interventions on ankle performance in subjects with chronic ankle sprains.

수면중 주기성 사지 운동에서 나타나는 야간 혈압 강하의 감소 (Decreased Nocturnal Blood Pressure Dipping in Patients with Periodic Limb Movements in Sleep)

  • 이미현;최재원;오성민;이유진
    • 수면정신생리
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    • 제25권2호
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    • pp.51-57
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    • 2018
  • 목 적 : 주기성 사지운동(periodic limb movement syndrome, PLMS)은 수면 중 팔다리를 비롯한 신체 일부가 불수의적이고 주기적으로 움직이는 현상을 말한다. 여러 연구에 의하면 PLMS는 고혈압의 위험인자로 잘 알려져 있고 각각의 PLMS 이후의 혈압이 20 mm Hg까지 증가한다는 연구도 있다. 본 연구에서는 PLMS가 수면 전후 혈압의 변화에 미치는 영향을 알아보고자 하였다. 방 법 : 야간 수면다원검사상 수면무호흡증이 없고(respiratory distress index < 5), 렘수면행동장애, 기면병 등의 수면장애가 없는 358명(남자 176명, 여자 182명)의 18세 이상 성인을 대상으로 하였다. 이들의 수면다원검사 기록과 수면다원검사 전 저녁 수축기, 이완기 혈압, 수면다원검사 후 아침 수축기, 이완기 혈압, body mass index, 음주, 흡연, 혈압강하제 복용 유무, 벡우울척도(Beck Depression Index), 엡워스졸음척도(Epworth Sleepiness Scale), 피츠버그수면질지수(Pittsburgh Sleep Quality Index)를 포함하는 임상 기록들을 수집하였다. 주기성 사지운동지수(Periodic Leg Movement Index) 15를 기준으로 15 이하인 군과 15 초과인 군으로 나누어 비교하였다. 두 군의 임상적 변수 비교는 t-test와 카이제곱 검정을 사용하였으며 repeated measure ANOVA를 사용하여 각 군에서의 검사 전후 혈압 변화 및 두 군의 혈압 변화 양상을 비교하였다. 결 과 : 대상자 전체에서 PLMS가 시간당 15초과한 군이 PLMS 15이하인 군에 비하여 수면 전후 수축기 혈압이 덜 감소하였다. 이러한 결과는 성별과 연령을 보정하였을 때에도 유의하게 나타났으나 BMI, 음주, 흡연, 혈압강하제 사용, sleep efficiency 변수들을 보정하였을 때에는 통계적으로 유의하지 않았다(0.098). 여성에서 두 군간 연령 이외의 다른 변수들은 유의한 차이를 보이지 않았다($49.0{\pm}14.6$세, $57.1{\pm}14.8$세, p = 0.001). 여성의 경우, 두 군 모두 검사 전, 후 수축기 혈압은 유의한 감소를 보였다(p < 0.001). PLMI 15 이하군의 수축기 혈압이 9.7 mm Hg 감소한 것에 비해 PLMI 15 초과군의 수축기 혈압은 2.9 mm Hg 정도만이 감소하여 수면 전, 후 수축기 혈압 변화 양상이 유의하게 차이가 났다($135.2{\pm}20.3mm\;Hg{\rightarrow}125.5{\pm}18.3mm\;Hg$, $133.5{\pm}17.9mm\;Hg{\rightarrow}130.6{\pm}14.8mm\;Hg$, p = 0.010) 이러한 결과는 연령, BMI, 음주, 흡연, 혈압강하제 복용 유무, sleep efficiency 변수를 보정하여도 유의하게 나타났다(p = 0.024). 남성의 경우 두 군 모두에서 수축기 혈압이 수면 전, 후 유의하게 감소하였지만 PLMS에 의한 교호작용(interaction effect)은 나타나지 않았다. 결 론 : PLMS는 수면 중의 정상 혈압 강하 패턴의 감소와 유의한 연관성이 있었으며 혈압과 관련된 임상 변수를 보정하였을 때에는 여성에서만 유의한 연관성을 보였다. 여성에서 PLMS와 관련하여 발생할 수 있는 고혈압 및 심혈관 질환의 임상적 의미를 확인할 수 있었다.

탄성밴드 사용유무에 따른 발레 아라베스크 동작의 운동 역학적 분석 (The Biomechanical Analysis of Ballet Arabesque by Using Elastic Band)

  • 김민정;이경옥
    • 한국운동역학회지
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    • 제25권3호
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    • pp.265-274
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    • 2015
  • Objective : The purpose of this study was to analyze the effect of the elastic band on ballet arabesque based on kinematics analysis. Methods : To observe the effect of the elastic band, the availability of the elastic band during movement was set as the independent variable, and the dependent variables were set by using factors from two different categories such as motor mechanics and kinematics variables. For motor mechanics variable, the muscle activity and the center of pressure(COP)'s trajectory and velocity were used. Furthermore, the physical angle was used for kinematic variables. Data samples from the experiment was used to understand the correlation between independent and dependent variables while using paired samples t-test as a data analysis tool. Results : After analyzing the result of experiment, the usage of the Elastic band on ballet arabesque movement seemed to increase the activity of the agonistic muscle, which is mainly used for movement, and to improve the stability of the supporting leg by decreasing the trajectory and velocity of the center of pressure(COP). Moreover, the elastic band increased the level of elevation of the stretching leg with reducing the angle of the hip joint that resulted into a more stable movement and furthermore providing more beauty while standing on it. Conclusion : The movement training program while the using elastic band are expected to lead to appropriate muscular development and reduce the muscle imbalance, which usually occurs to dancers, during training with unfamiliar specific movements or strengthening muscular strength for a specific movement. In addition, this work is expected to be used as a training reference to understand and learn the fundamentals of movements of ballet and other dance fields.