한국 여성 노인용 신발의 LAST 설계를 위한 인체 발 측정치에 관한 연구

곽창수(Chang Soo Kwak),이경옥(Kyung Ok Yi) 한국여성체육학회 2000 한국여성체육학회지 Vol.14 No.1

The purpose of this study was to provide fundamental foot measurement data essential for shoe LAST design suitable for physical characteristics of Korean aged women to enhance their health and prevent injuries. The subjects employed for this study were 250 old women who lived in the metropolitan area and over 60 ages. They had never experienced an surgery and pain in foot region. The variables for foot measurement were 42 regions, and specific measurement method for variables was used KS A7003 and KS A7004 provided by the Korean industrial standards association and measured foot regions by Martin rulers. The findings of results were as follows: 1. The variables for foot measurement were 42 regions which was 10 for foot height, 8 for foot girth, 16 for foot length, 5 for foot width, and 3 for foot angle. Thus it was the most items related to the foot measurement survey which ever studied and sampling size was 250 old women, which was the largest of specific group sampling size. 2. It showed that there were no foot measurement items shown big differences, but there were some items shown small differences compared with former studies. 3. There were no differences in percentiles in comparison with former studies. It was assumed that it resulted from small sampling size of former studies and measurement errors. 4. The highest correlation between variables was between ankle girth and heel-ankle girth, and correlation coefficient was r=0.67. However, most correlation coefficient between variables was appeared to be very low. The study found out that foot measurement data was no diffenence from former surveys, but there were few variables which showed small differences. Also, it was thought that measurement variables and sampling size of this study had been developed relative to former surveys. Foot measurement data should be applicable to shoe LAST design and verify this data by shoe subject testing in the future.

중량물을 부가한 워킹화 신발바닥의 적정경도 분석

곽창수 ( Chang Soo Kwak ),전민주 ( Min Ju Jeon ) 한국스포츠과학원 2011 체육과학연구 Vol.22 No.4

The purpose of this study was to evaluate the function and the safety of optimal hardness with additional weight shoes developed for the improvement of aerobic capacity and to improve some problems found in subject`s test utilizing thick and heavy sole shoes. The subjects employed for this study were 15 obese male adolescents and 10 obese female adolescents. Additional weight shoes developed for this study had shore A 65, shore A 78, shore A 91, shore A 104 of midsole hardness each. The results of the study were as follows; 1. The change of initial achilles tendon angle and initial rearfoot pronation angle of additional weight shoes during walking increased according to the hardness of shoes sole for male, but except shore A 91 in female subjects. 2. Maximal impact force of additional weight shoes increased according to the hardness of shoe soles. The time to maximal impact force of an additional weight shoes was about 19-20% of total ground contact time for each cases. Maximal vertical ground reaction force and force loading rate of additional weight shoes were appeared to be no difference between hardness. The time to maximal vertical ground reaction force was about 55-58% of total ground contact time for each cases and there was no difference among subjects as well as hardness. 3. In maximal joint momert, flection moment of hip joint was the biggest for males and females. Each joint moment showed small figure under expectation, and showed no significant tendency between joints and hardness generally. 4. In maximal amplitude of heel contact phase, tibial muscle showed the biggest figure and soleus mucsle showed the biggest figure in take-off phase. It did not show any relationships between maximal amplitude and hardness, and the recruitment of each muscle was appeared to be different between sex. 5. The distribution of maximal pressure was improved to be compared with the old additional weight shoe. M3 of regional maximal pressure was decreased to 13% in males, and 12% in females. The optimal hardness of additional weight shoe sole to improve the improvement of aerobic capacity for adolescents was shore A 65 through hardness analysis of various shoe evaluation variables in this study. There were some valuables not satisfied in this study, shore A 65 was the optimal hardness overall. In addition. this study had proven the safety of additional weight shoe which some people had been debating that additional weight shoe might caused the joint injury for adolescents because of heavy shoe weight.

중량물 부가 두꺼운 신발바닥의 적정두께 분석

곽창수 ( Chang Soo Kwak ),전민주 ( Min Ju Jeon ),정경석 ( Kyeong Seok Jeong ) 한국스포츠과학원 2010 체육과학연구 Vol.21 No.4

The purpose of this study was to evaluate the function and the safety of an additional weight shoe sole developed for the improvement of aerobic capacity and to improve some problems found in subject`s test utilizing thick sole shoes. The subjects employed for this study were 15 obese male adolescents and 10 obese female adolescents. Additional weight shoes developed had 21mm, 34mm, 46mm, 59mm of shoe sole thickness each. The results of the study were as follows: 1. The change of initial achilles tendon angle and initial rearfoot pronation angle of additional weight shoes during walking increased according to the thickness of soles for both male and female subjects and showed substantial difference between 34mm and 46mm. 2. Maximal anterior posterior ground reaction force of additional weight shoes increased according to the thickness of soles. The time to MAPGRF of an additional weight shoes was about 20% of ground time for each cases. Maximal vertical ground reaction force of additional weight shoes were appeared to be 9.85-10.14B.W. for males and 8.25-9.96B.W. for females. 3. In maximal joint moment, flection moment of hip joint was the biggest for males and flection moment of ankle joint was the biggest for females. Each joint moment showed small figure under expectation, specially, rotation moment and supination moment of each joint showed small figure generally. 4. In maximal amplitude of heel contact phase, tibial muscle showed the biggest figure and soleus muscle showed the biggest figure in push-off phase. Maximal amplitude had increased according to the thickness of soles for both phases. The optimum thickness of additional weight shoe to improve the improvement of aerobic capacity for adolescents was to be 34mm in this study. There were some valuables not satisfied in this study, 34mm was the optimum thickness overall. In addition, this study had proven the safety of additional weight shoe which some people had been debating that additional weight shoe might caused the injury of joint for adolescents.

운동화 굴곡강도에 따른 주행효율(Running Economy)과에너지 반환(Energy Return)과의 관계

곽창수 ( Chang Soo Kwak ),이충일 ( Chung Il Lee ),권영후 ( Young Hoo Kwon ),전민주 ( Min Ju Jeon ) 한국스포츠과학원 2014 체육과학연구 Vol.25 No.3

The purpose of this study was to investigate the effect of running economy and energy return in lower extremities according to the increase of bending stiffness of the shoes, furthermore to investigate the relationship between running economy and energy return for the improvement of sports performance. Subjects employed for this study were 10 healthy male college students who have not had the experiences in lower extremities injuries. Four different kinds of shoes in bending stiffness as with 0.56 N/mm, 0.74 N/mm, 0.96 N/mm, 1.21N/mm were used respectively. 3-D cinematography and pulmonary gas analyzer were utilized for energy return and energy consumption data during running according to the increase of bending stiffness of the shoes to obtain the following results. As the bending stiffness of running shoes increased, the statistical significance were not founded, however, the tendency of decrease in max. flexion moment and power, increase in max. extension moment and power in lower extremity joint were showed. Joints energy showed no statistical significance in phase 1, however, the tendency of lesser absorbtion as the bending stiffness of running shoes increased were showed. More energy were generated as the bending stiffness of running shoes increased in phase 2 with no statistical significance. Energy economy increased according to the increase of bending stiffness of running shoes. Negative correlation were showed between flexion moment of hip joint and energy consumption(p<0.05). Slightly higher degree of correlation between max. flexion power of hip and ankle joint and energy consumption were showed without statistical significance. Negative correlation were showed between joints energy and energy consumption for ankle joint in phase 1(p<0.05).

달리기 속도의 증가에 따른 운동화 중저의 경도와 신발바닥의 두께가 신발의 볼 굴곡각도에 미치는 영향

곽창수 ( Chang Soo Kwak ),목승한 ( Seung Han Mok ),권오복 ( Oh Bok Kwon ) 한국운동역학회 2005 한국운동역학회지 Vol.15 No.4

유산소 운동능력 향상을 위한 중량물 부가 신발의 기능성 평가

곽창수 ( Chang Soo Kwak ),김희석 ( Hee Suk Kim ) 한국운동역학회 2004 한국운동역학회지 Vol.14 No.3

C. S. KWAK, H. S. KIM. The Evaluation of an additional Weight Shoe`s Function developed for the Improvement of Aerobic Capacity, Korean Journal of Sport Biomechanics, Vol. 14, No. 3, pp. 67-82, 2004. 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.

운동화의 생체역학적 평가시 하지 회내운동의 운동학적 평가변인에 대한 상해 기준치 연구

곽창수 ( Chang Soo Kwak ),전민주 ( Min Ju Jeon ),권오복 ( Oh Bok Kwon ) 한국운동역학회 2006 한국운동역학회지 Vol.16 No.4

측면 이동속도변화에 의한 점프 후 착지 시 충격흡수와 후족운동과의 관계 연구

곽창수 ( Kwak Chang-soo ),전민주 ( Jeon Min-ju ),성금주 ( Seong Keum-ju ) 한국융합과학회 2022 한국융합과학회지 Vol.11 No.8

Purpose The study was aimed to find out the influence of lateral movement velocity on rearfoot stability and impact force absorption and to identify the corelation between rearfoot control variables and ground reaction force variables. Method The subjects employed for this study were ten college students with normal foot and had no injuries in lower extremities. Motions of lower extremity during landing after lateral movement jumping at 3 different velocity were analyzed by using 12 infrared cameras and a kistler force platform. Result Rearfoot control variables amd ground reaction force variables were increased by lateral movement velocity with the increment. Instantaneous angular velocity of the time to maximal impact force and maximal vertical ground reaction force was appeared to be lowest at knee joint angle. The corelation between rearfoot control variables and ground reaction force variables was appeared to be low overall. Conclusion This study identified that rearfoot control variables and impact force variables were increased with the increment of lateral movement velocity. Also similar results were shown at the different landing technique of toe-heel different from general running. It have been known that a foot pronation makes shock attenuation at the contact of ground. However, this study did not appear to be no relation between two variables. Initial achilles tendon angle showed the highest corelation in rearfoot control variable and maximal impact force loading rate in impact absorption variables. Therefore when we consider to evaluate the possibility of injury efficiently, we evaluate these two variables requisitely.

신발의 착화시 인지적 편안함과 관련된 요인 분석

곽창수 ( Chang Su Kwak ),이충일 ( Chung Il Lee ),양정수 ( Jung Soo Yang ),전민주 ( Min Joo Jeon ),목승한 ( Seung Han Mok ) 한국스포츠과학원 2007 체육과학연구 Vol.18 No.2

Korean shoes industry has been playing a substantial role in Korean economy, however the issue of lack of international competitiveness was raised and discussed in spite of its great potential. The primary reason for this is thought to be the lack of know-how on comfort footwear. Therefore, the purpose of this study was to find out the factors on comfort so that the Korean shoes industry can enhance and develop the new developing technology using the results of this study. Subjects in this study were 30 male university students with normal foot and no injury in lower extremity. Total of 22 shoe conditions were tested on shoe comfort and top 10 factors were analyzed using cinematography and ground reaction force measurement. Results of this study were as followings. 1. The best shoes in comfort cognition test had forefoot region 50 degree, rear-foot region 50 degree in mid-sole hardness, high arch in insole, standard last, and 2mm hill counter thickness. 2. Comfort was best when forefoot region thickness was in standard last level and hill-counter thickness was 2mm. 3. High and standard arch created comfort. Therefore, this factor should be considered when designing shoes or insole. 4. In two speed condition, pronation moment in hip joint and knee joint was decreased and they had little effect in comfort ratings. 5. Total change of rear-foot angle and total change of Achilles tendon angle was 7-11 degree, 10-13 degree in top 10 shoe conditions by the two speed condition, respectively and they had little effect in comfort ratings. 6. Forefoot region hardness should not be under 50 degree. Otherwise, pronation moment in hip, knee, ankle joint were increased. 7. Bottom up phenomenon might not happen with over 40 degree in mid-sole hardness for subjects under 70kg of body weight. Specially, for subjects over 50kg, it is thought that bottom up phenomenon will not happen, so this finding will be useful for designing shoes. Specially, medio-lateral control was ranked the fourth in spite that LAST round of hill-counter region was big with shoes-size of 280mm (standard 270mm). This finding suggests future study that medio-lateral control has little to do with rear-foot round but might have something to do with motion patterns and mid-sole hardness. Additionally, it is founded that pronation moment in knee and ankle joint was small when mid-sole hardness was small. This finding is contrary to the findings of former studies which found that pronation movement would increase as mid-sole hardness in rear-foot region would decreased, therefore future study for examining this should be followed.

역학 : 신발의 압력분포측정을 위한 압력매트 개발

곽창수,한광록,정동명 ( Chang Soo Kwak,Kwang Rok Han,Dong Myung Jung ) 한국체육학회 1992 국제스포츠 학술대회 Vol.1992 No.-