• Korean Journal of Rural Living Science
• /
• v.7 no.2
• /
• pp.99-108
• /
• 1996

This study has intended to suggest fundamental data to develope and choose appropriate shoes for upland farming in order to prevent health deterioration of women workers and improve work effectiveness and reduce fatigue by wearing appropriate shoes. During 1995. 4. 28 - 5. 10, Fifty women workers in hot pepper farming were observed and major shoe types, which were rubber shoes, walking shoes, slippers, and rubber boots, were selected for the study. During 1995. 10. 9 - 31, two subjects were tested by wearing those shoes in the laboratory where the temperature was 24$\pm$1$^{\circ}C$ and relative humidity 50$\pm$5%RH. And the temperature & humidity on sole and in the shoes, the rectal temperature, skin temperature, blood pressure, pulse, lactate concentration of blood, Flickers' value and subjective sensation were measured. The results were as follows : 1. 84% of women workers mentioned that they need shoes improvement and the order of most frequent shoe types to be worn was rubber shoes, walking shoes, slippers, rubber boots. 2. The rate of women who were unsatisfied with shoes for upland farming is 38 percentages. The reason of unsatisfaction was that feet were in a sweat and alien substances were let into shoes. 3. The temperature & humidity on sole were the lowest in rubber boots during experiment(p＜0.01). 4. The relative humidity in the shoes was the highest in rubber boots by 90% and the lowest in walking shoes by 72% during rest And the humidity in slippers and walking shoes were significantly low in experiment(p＜0.001). 5. Rubber boots showed the highest rise in rectal temperature by 0.2$^{\circ}C$ showing increase of core temperature (p＜0.05). 6. The mean skin temperature during experiment was highest in rubber boots by 33.8$^{\circ}C$(p＜0.001).

• Korean Journal of Applied Biomechanics
• /
• v.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.

• Proceedings of the KAIS Fall Conference
• /
• 2001.11a
• /
• pp.196-200
• /
• 2001

Foot has two functions : one is walking (or propulsion), the other is supporting or protecting of human body. In spite of such important roles, the importance of foot in keeping health has been easily disregarded. The bottom of foot is usually regarded as the second heart, for it is the pocket edition of all the principal parts of human body. Shoe is one of the tools to protect foot, and to wear a good shoe is the most demanded point in keeping health, Shoe can be different in kinds and shapes according to each one's usage. That is, different conditions of different people should have the different results in the material, design, last, pattern and structure in manufacturing shoe. A good shoe is absolutely a shoe with its right suitability, elasticity and adaptability. To make this healthy shoe, it is needed to design in the way of human technology, and the relative and scientific materials are basically required in manufacturing it. Recently there is an increasing demand for milti-functional shoe that can improve the efficiency of work in parallel with the maintenance of health. Accordingly this paper put its main purpose on the development of a healthy shoe based on proper and right theory and test.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.04a
• /
• pp.515-528
• /
• 1995

Slips and falls are the major causes of the pedestrian injuries in the industry and the general community throughout the world. With the awareness of these problems, the friction coefficients of the interface between floorings and footwear have been measured for the evaluation of slip resistant properties. During this measurement process, the surface texture has been shown to be substantially effective to the friction mechanism between shoe heels and floor surfaces under various types of walking environment. Roughness, either of the floor surface or shoe heels, provides the necessary drainage spaces. This roughness can be designed into the shoe heel but this is inadequate in some cases, especially a wear. Therefore, it is essential that the proper roughness for the floor surface coverings should be provided. The phenomena that observed at the interface between a sliding elastomer and a rigid contaminated floor surface are very diverse and combined mechanisms. Besides, the real surface geometry is quite complicate and the characteristics of both mating surfaces are continuously changing in the process of running-in so that a finite number of surface parameters can not provide a proper description of the complex and peculiar shoe - floor contact sliding mechanism. It is hypothesised that the interface topography changes are mainly occurred in the shoe heel surfaces, because the general property of the shoe is soft in the face of hardness compared with the floor materials This point can be idealized as sliding of a soft shoe heel over an array of wedge-shaped hard asperities of floor surface. Therefore, it is considered that a modelling for shoe - floor contact sliding mechanism is mainly depended upon the surface topography of the floor counterforce. With the model development, several surface parameters were measured and tested to choose the best describing surface parameters. As the result, the asperity peak density (APD) of the floor surface was developed as one of the best describing parameters to explain the ambiguous shoe - floor interface friction mechanism. It is concluded that the floor surface should be continuously monitored with the suitable surface parameters and kept the proper level of roughness to maintain the footwear slip resistance. This result can be applied to the initial stage of design for the floor coverings.

• PNF and Movement
• /
• v.11 no.2
• /
• pp.21-29
• /
• 2013

Purpose : The study was to evaluate the weight distribution, balance and gait function of stroke patients wearing lateral wedged insole to the shoe of the affected side. Methods : 27 patients with stroke (15 men, 12 women) participated in this study. Participants performed weight distribution, dynamic balance and gait ability with or without wedged insole on affected side in a random order. The balancia was used to evaluate the weight distribution. Deviation from the center line was analyzed by Dartfish during sit to stand to evaluate dynamic balance. The functional walk ability evaluated by 10 m walking velocity. Results : The asymmetry index of weight bearing improved significantly with wedged insole of affected side(p<.05). During sit to stand, center of gravity significantly moved from non-affected side to more mid line of body(p<.05). Improvement were shown in walking speed after wearing the wedged insole(p<.05). Conclusion : Wedged insole applied on affected side have a beneficial effect on weight distribution, dynamic balance and walking speed with stroke.

• Journal of Convergence for Information Technology
• /
• v.8 no.6
• /
• pp.59-66
• /
• 2018

The utilized coefficient of friction (UCOF) as a ratio of the shear force to the normal force on the ground during walking is used to identify the point at which slip is likely to occur. Shoe walking will change the utilized coefficient of friction by shoe design such as sole thickness and hardness, heel shape, and outsole pattern. In this study, subjects are 21 adults (10 female, 11 male, age: $25.2{\pm}2.3yrs$, height: $165.6{\pm}7.2cm$), analysis variables were walking speed, GRF, when the UCOF is maximal, and Tangent of CoP-CoM angle, and correlation analysis with the utilized friction coefficient (UCOF). As a result, First, for the shod walking the time point which UCOF is maximum about heel strike was faster and the magnitude was larger than for barefoot walking. Second, the correlation between the tangent of CoP-CoM and UCOF of right foot was higher at the left heel striking point (UCOF2_h) which occurred in the post propulsion phase than at the right heel striking point (UCOF1_h). This suggests that the right foot UCOF is related to the braking phase of left foot( which is the propulsion phase of right foot) rather than the braking phase of right foot.

• Journal of Korean Physical Therapy Science
• /
• v.26 no.3
• /
• pp.70-75
• /
• 2019

Purpose: The purpose of this study was to investigate the changes of static and dynamic balance control ability according to the stability of shoes in elderly woman and female university student. Design: Cross-sectional study. Methods: Six elderly women and seven female university students were recruited for this study. The subject's static and dynamic balance were evaluated while wearing two different types of shoes (comfortable running shoe and masai walking shoe). The BT4 system was used to measure the static (postural sway area and velocity) and dynamic balance (limit of stability on forward, backward and left and right side). The measurement of static and dynamic balance control ability was performed in standing posture wearing comfortable running shoes and masai walking shoes. Results: In the static balance control ability, both female university students and elderly women showed significant increase in postural sway area and velocity when wearing unstable shoes (p<0.05) In addition, in the dynamic balance control ability, both female university students and elderly women showed significant decrease in limit of stability on forward and backward when wearing unstable shoes (p<0.05). Conclusion: In selecting shoes for the elderly, the stability of shoe should be considered for prevention of falls.

• Journal of the Ergonomics Society of Korea
• /
• v.26 no.1
• /
• pp.71-77
• /
• 2007

Shoe's size and shape are determined by the last that takes shape of foot because last is the mold of shoe in development and manufacturing process. Then adaptation between foot and shoe is dependent on the last. In mass shoe production, model size is developed in the first place, other sized lasts are made through the grading process based on model size. The most important factor in grading system is grading deviation that must be same amount induced from foot measuring database. At present, most of the last manufacturing companies in korea using 260mm as a standard foot model size. When length grading deviation is 5mm, the ball girth grading deviation is 3.7mm and the ball width grading deviation is 1.2mm. I verified existing grading system by comparing grading results with foot measuring data. Also, I proposed reasonable grading deviation and application method of grading system. From the analysis of foot measuring database, reasonable grading deviations are 1.22mm in ball width and 0.84mm in ankle height in case of length grading deviation is 5mm. I confirmed that the current grading system is very accurate. When we grade last from 230mm to 290mm by current grading system based on model size 260mm, there is grading error over 1mm in the front outside area of foot. This error level of 1mm is no problem in normal walking shoe's last, but it induces adaptation problems in sports and special purposed shoe's last. Therefore using of three standard model size is recommended in grading men's last for reducing grading deviation error under the level of 1mm. It is specifically described as 235mm in 225-245mm, 260mm in 250-270mm, 285mm in 275-295mm. According to the above recommended grading system, it is enough to measure only three foot sizes in case of foot measuring project for men's last development.

• Korean Journal of Applied Biomechanics
• /
• v.16 no.2
• /
• pp.1-8
• /
• 2006

The purpose of this study was to evaluate normalized jerk according to shoes, slope, and velocity during walking. Eleven different test subjects used three different types of shoes (running shoes, mountain climbing boots, and elevated forefoot walking shoes) at various walking speeds(1.19, 1.25, 1.33, 1.56, 1.78, 1.9, 2, 2.11, 2.33m/sec) and gradients(0, 3, 6, 10 degrees) on a treadmill. Since there were concerns about using the elevated forefoot shoes on an incline, these shoes were not used on a gradient. Motion Analysis (Motion Analysis Corp. Santa Rosa, CA USA) was conducted with four Falcon high speed digital motion capture cameras. Utilizing the maximum smoothness theory, it was hypothesized that there would be differences in jerk according to shoe type, velocity, and slope. Furthermore, it was assumed that running shoes would have the lowest values for normalized jerk because subjects were most accustomed to wearing these shoes. The results demonstrated that elevated forefoot walking shoes had lowest value for normalized jerk at heel. In contrast, elevated forefoot walking shoes had greater normalized jerk at the center of mass at most walking speeds. For most gradients and walking speeds, hiking boots had smaller medio-lateral directional normalized jerk at ankle than running shoes. These results alluded to an inverse ratio for jerk at the heel and at the COM for all types of shoes. Furthermore, as velocity increased, medio-lateral jerk was reduced for all gradients in both hiking boots and running shoes. Due to the fragility of the ankle joint, elevated forefoot walking shoes could be recommended for walking on flat surfaces because they minimize instability at the heel. Although the elevated forefoot walking shoes have the highest levels of jerk at the COM, the structure of the pelvis and spine allows for greater compensatory movement than the ankle. This movement at the COM might even have a beneficial effect of activating the muscles in the back and abdomen more than other shoes. On inclines hiking boots would be recommended over running shoes because hiking boots demonstrated more medio-lateral stability on a gradient than running shoes. These results also demonstrate the usefulness of normalized jerk theory in analyzing the relationship between the body and shoes, walking velocity, and movement up a slope.

• The Journal of Korean Physical Therapy
• /
• v.23 no.3
• /
• pp.49-56
• /
• 2011

Purpose: To evaluate changes in lower extremity muscle activity caused by high heeled shoe wearing during normal, brisk, and upslope walking. Methods: Twenty healthy young women (age, $23.9{\pm}2.47$) participated in this study. Muscle activities of the tibialis anterior, peroneus longus, gastrocnemius lateralis, gastrocnemius medialis, soleus, hamstring, vastus lateralis, and vastus medialis while walking normally, walking briskly, and walking up a slope. Results: When walking normally, the peroneus longus, gastrocnemius lateralis, soleus, and vastus lateralis evidenced higher activity when high-heeled shoes were worn (p<0.05). During brisk walking, the peroneus longus and gastrocnemius lateralis exhibited higher activity (p<0.05). Although the peroneus longus and vastus lateralis exhibited higher activity when walking up an incline with high-heeled shoes, the activity levels of the tibialis anterior and gastrocnemius medialis were lower (p<0.05). Conclusion: The results of this study demonstrate that increased heel height substantially reduces muscle effort when walking up a slope. From a therapeutic perspective, it is possible that using high heeled shoes over a short period might enhance muscle activity of ankle evertor, although it can cause mediolateral muscle imbalances in the lower extremities.