• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.319-325
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• 2010

The purpose of this research was to investigate the differences in the ski carving turn motion according to level of expertise. The posture and movement of 6 skiers nearby the fall-line was evaluated with a biomechanical approach focusing the rotational mechanics. The slope was at an angle of $9^{\circ}$ and the following variables were measured and calculated: tangential velocity, change of COM height after passing fall-line, width between feet, angle between upper body and thigh, trunk angle, average radius of curvature and average centripetal force. The expert skiers minimized their center of mass height movement and maintained the width of between their feet after the passing the fall-line in comparison with the beginners and intermediate skiers. The experts restrained themselves from pushing their upper body downward after the turn to maximize the centripetal force. The experts in comparison with the beginners and intermediate skiers during the turn didn't have to reduce their radius of curvature to maintain a high centripetal force. It was concluded, that the most important factor affecting the centripetal force, was for the beginners and intermediate skiers, to minimize their movement while using the appropriate amount of edging.

• The Journal of Korean Physical Therapy
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• v.32 no.1
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• pp.29-33
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• 2020

Purpose: This study examined the effects of the weight-bearing pattern and calcaneal taping on the heel width and plantar pressure in standing. Methods: Fifteen healthy subjects with normal feet participated in this study. The heel width was measured using a digital caliper, and a pedoscan was used to measure the plantar pressure of the rear foot while standing. The participants were instructed to stand in three weight-bearing patterns (anterior, middle, and posterior weight bearing) before and after calcaneal taping. The heel width and plantar pressure were measured three times before and three times after calcaneal taping, with the three weight-bearing patterns applied in random order. A 2 (non-taping vs. taping) × 3 (anterior, middle, posterior weight bearing) two-way repeated ANOVA with a Bonferroni post hoc correction was used to assess the differences in heel width and plantar pressure. Results: The results revealed a significant main effect of the weight-bearing pattern (p<.01), but not of calcaneal taping (p>.05). Greater weight bearing applied to the heel resulted in a significantly increased heel width and planter pressure of the rear foot (p<.01). Conclusion: In standing, a posterior weight-bearing pattern increases the heel width due to side-to-side shifting of the plantar heel pad, which increases the heel plantar pressure. Therefore, to prevent high stress on the heel pad and plantar heel pain, it is important to refrain from posterior weight bearing while standing during the activities of daily living.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.134.2-134
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• 2001

This paper treats the implementation of a statically stable control system for a biped walking robot with 10 degrees-of-freedom. Statically stable walking of a biped robot can be realized by keeping the center of mass (COM) inside the sole of the supporting foot (or feet) during single-support or double-support phases. We predetermined five static positions for walking based on the COM method. The positions can be represented by the length of the gait, the width between the feet, the height of the foot and two parameters in the hip movement. With the five parameters, we calculated the position trajectory. And we got the angular trajectories of 10 joints from the posit ion trajectory using the position tracking control and neural network. By tracking the angular trajectories, the robot can walk maintaining stability. We implemented walking of a biped robot throught the above ...

• Journal of the Korean Society of Costume
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• v.52 no.2
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• pp.71-80
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• 2002

The purpose of this study was to examine the correlation between the shape of the foot and foot abrasion. and to provide preliminary data for shoe manufacturing by comparing the length of a woman's feet and the shoe size. The Martin calibrator and measuring tapes were utilized to measure the shapes of 163 female college students' feet. Indirect measurements were also obtained by line drawing of the feet for additional analysis. Brief questionnaires about what type of shoes are worn were given to the subjects of the study. Data analysis was presented by frequency, percentage, and standard deviations. Factor analysis and correlation co-efficiency of data was conducted on the significance level of p〈.05. The results of the study are as follows (1) The average number of days per week in which the subjects wear ladies' shoes per week were 4.5. Little over half of the subjects (53.87% ) answered that they wear heeled shoes for more than 8 hours per day. The most preferred height of a ladies'shoe heel was between 2 cm and 4 cm, as replied by 41.0% of the subjects. (2) The foot area where abrasion occurs most often was around the heel (51.2%) and the middle part of the sole (50.9%) (3) Factors correlated to the heel abrasion included the circumference and the breadth of the foot. The abrasion on the side of the first toe of mid-sized feet was most affected by the angle of the first the and inner foot line. The height of the foot heel was a significant factor for the abrasion near the anklebone. In conclusion, the abrasion resulted from the inappropriate fitting of the shoe and the foot. Also, the circumference and the width factors were more influential rather than the foot length. Therefore, more database on this should be systemized and available to the footwear manufacturers and the customers for more practical use of shoe size and public education.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.10 no.1
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• pp.67-81
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• 2004

The purpose of this study was to investigate between low back pain scale and disability index owing to gait pattern. For the period of February 1 to February 29, 2004, we had conducted a questionnaire and direct interview with 100 persons lived in Daejeon. The result were as follows: 1. The stride length of experimental group, the male was $49.9{\pm}12.9cm$, the female $45.7{\pm}12.9cm$ and the width of feet. the male was $13.5{\pm}5.7cm$, the female $12.2{\pm}4.8cm$. 2. The Fick angle of all subjects was showed in external disposition, the left angle showed in asymmetry, the male was $11.0{\pm}5.7^{\circ}$, the female $8.5{\pm}1.3^{\circ}$. 3. The foot arch was similar to sex as a weight bearing and non-weight bearing, the male was $1.3{\pm}0.8cm$, the female $1.3{\pm}0.9cm$. 4. The impedimental index according to back pain grade, men was a lower than women, the male was $5.7{\pm}6.9$ and the female $7.2{\pm}5.3$. 5. The relation to difference between foot arch and disability index according to back pain grade as a weight bearing and non-weight bearing, the higher foot arch, the higher back pain grade was statistically significance(p<.05). 6. The relation between width of feet and disability index according to back pain grade, the wider width of feet, the higher back pain grade was statistically significance(p<.01). 7. The relation between stride length and disability index according to back pain grade, the wider stride length, the higher back pain grade was statistically significance (p<.05).

• Journal of Korean Foot and Ankle Society
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• v.4 no.1
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• pp.5-12
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• 2000

Purpose: The purpose of this study is to assess the amount of changes in the foot size on weight bearing in adult women, which might help in choosing an appropriate size of the shoes. Materials and Methods: The authors measured the length and width of the feet of 200 healthy women on weight bearing and non-weight bearing, and the size of the shoes they wore. Results: Foot length and width differences between right and left sides were 2.53 mm and 2.16 mm respectively on non-weight bearing, and 2.47 mm and 1.77 mm respectively on weight bearing. Foot length and width increased by 2.89% and 7.50% respectively on weight bearing than those on non-weight bearing. Shoe width was 6.82% longer and 9.54% narrower than the weight bearing foot size. There were 25 women who had shoe-related foot pain, all of them wore shoes that were 13.01 % or more narrower than the weight bearing foot width. Foot pain was significantly correlated with the shoe-foot width difference(p=0.0001). Conclusion: The foot size was increased by 2.89% in length and 7.50% in width with weight bearing. The width of their shoes was narrower. than the weight bearing foot width. Shoe-related foot pain was correlated with the foot-shoe width difference.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.5 s.142
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• pp.595-606
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• 2005

The purpose of this study is to identify foot shapes of elderly women by classifying their foot types according to the shapes of sole (plantar view) of foot and analyzing the characteristics of each type. The subjects were 321 elderly women over 60 years of age. Their right feet were measured indirectly by using .scanner. The anthropometric measurements consist of 32 items. They were measured during the months of July and August in 2001. The results and discussions of this study are as follows. First, in analyzing sole of the foot of elderly women, the shapes of sole were classified as W-type (wider width for its length and severe alteration), A-type (similar to W-type but with narrower width), D-type (protruded outside) and H-type (even foot width). Second, the most characteristic sole type in elderly women was W-type. In this type, the width was wider for its length, the first metatarsophalangeal protrusion was severe and the toes were gathered at the center. Hopefully, understanding the shapes of sole and characteristics of each sole type will help to develop suitable shoes for elderly women.

• Journal of International Academy of Physical Therapy Research
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• v.3 no.1
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• pp.391-396
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• 2012

The purpose of this study is to identify which width of the base of support(BOS) is safer and more effective in lifting by comparing muscle activations and body sways when lifting objects under the width variation of the BOS. A total of fifteen healthy adults participated in this study. For the width variation of the BOS, the participants changed the width between their feet into three different types(10cm, 32cm, 45cm) and lifted a 10kg four times in each type after going up on a force plate. In order to measure body sways according to the width variation of the BOS, a motion analysis system was used. In addition, in order to measure the muscle activations of lower extremities, including the erector spinae, gluteus maximus, rectus femoris, and tibialis anterior, an electromyogram(EMG) analysis was employed. In addition, the Borg's scale was drawn by quantifying the subjective discomfort levels felt from each width of the BOS. In conclusion, no statistically significant differences according to the width variation of the BOS were observed(p=.295, .308)(p>.05). However, a statistically significant difference was exhibited between the Borg's scale, which indicates the discomfort levels from lifting performances, and the width variation of the BOS (p=$.000^*$).

• Journal of Fashion Business
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• v.8 no.6
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• pp.78-89
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• 2004

With 100 collegians residing in Busan, a shoes wearing survey was held. Out of the subjects, 50 women collegians showing some interest in fashion sneakers were chosen to reveal the effects of shoes size changes on walking patterns and wearing sense. This study focused on the fitness of sneakers produced the following results: 1. Survey Results of Shoes Wearing The subjects had some room in wearing sneakers or athletic shoes, including $20{\sim}30mm$ (33%). Just 25% of the subjects reported about the experience of falling, and 67.6% had difficulty walking on downhills. 50% felt feet fatigue difference when wearing fitting and unfitting shoes. 2. Analysis of Walking Patterns & Survey Results of Wearing Sense No significance was found among shoes sizes in left and right step angles. Step width measurement revealed no significance among shoes sizes. Significance ($p{\le}.05$) existed among shoes sizes in steps and strides. Significance ($p{\le}.001$) was noticed among shoes sizes in wearing sense.

• The Journal of Dong Guk Oriental Medicine
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• v.5
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• pp.79-95
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• 1996

When we see normal gait, gait cycle is seperated as stance phase and swing phase. It needs 6 determinant of gait of pelvic rotation, pelvic tilt, knee joint of stance phase, ankle and foot motion, ankle and knee motion, and pelvic movement to be accomplished. In addition, a joint and muscle action is accomplished biomechanically at the same time with its gait cycle. In oriental medicine, the relationships between chang-fu physiology and meridian physiology are summaried as follows ; ${\bullet}$ chang-fu physiology : Spleen manages the extremities. Liver manages soft tissues. Liver stores blood. Kidney stores essences. Kidney manages bones. ${\bullet}$ meridian physiology : The Leg Greater Yang Meridian and meridian soft tissues The Leg Yang-Myeong Meridian and meridian soft tissues The Leg Lesser Yang Meridian and meridian soft tissues The Leg Greater Yin Meridian and meridian soft tissues The Leg Lesser Yin Meridian and meridian soft tissues The Leg Absolute Yin Meridian and meridian soft tissues Especially, we can find out relations between in a "blood supplied feet can walk well" that explains "blood regulations and by liver nourishing effects"that is the closest concept of muscle. Abnormal gaits are due to three causes as following; first, physical defect secoud, pain third, nervous system or instability of muscle. In oriental medicine, we can know relationship in "atrophy, numbness, stroke, convulsion, muscular dystrophy of knee, rheumatoid arthritis, five causes of infantile growing defects, five causes of softening, sprain". Especially, atrophy is the most important symptom. Gait evaluation should be emphasized where a point can walk 8 feet to 10 feet considering stride width, stride length, the body weight center, stride number, flexion, extension, rotation of a joint as a standard factor. The point is we should find out something strange in a patient's side, front and back view. After that we should find out its cause as an index that we can observe abnormal findings in a joint and muscle.