Jung-Hyeon Yoo

Comparative Analysis of Foot Pressure Distribution by Functional Insole to be Transformed and Restored During Walking

The purpose of this study was to analyze the distribution of foot pressure generated by active materials of a functional insole. Comfort is an important consideration while selectingfootwear and insoles. Consequently, it has an influence on injury. The development of new materials for functional insoles is considered one of the more important points for their manufacture. The method adopted in this study is as follows. First, ten healthy males were selected as subjects for the study. Each subject`s foof was pre-screened podoscope(Alfoots, Korea) to check for the presence of any foot abnormalities, Two kinds of equipment were used for the study: a foot pressure device from Pedar-X, Germany, and a treadmill from Pulsefitness, UK. Next, each subject was asked to test four types of insoles(insoles of outdoor shoes, indoor shoes, walking shoes, and sports shoes) via walking trials on the treadmill at a constant speed of 4.2 km/h. The pressure distribution data(contact area, maximum force, maximum peak pressure, and maximum mean pressure) was collected using the pressure device at a sampling rate of 100 Hz. Results of the tests showed that all four types of functional insoles increased contact areas whit the foot. Further, functional insoles of walking shoes and sport shoes decreased the foot pressure. From these results, we conclude that the active materials of functional insoles of shoes can increase the contact area and provide greater comfort.

Biomechanical Analysis of Trail Running Shoes Applied to Korean Shoe-Lasts

【The purpose of this study was to analyze biomechanical factors of trail running shoes applied to korean shoe-lasts. 10 healthy male subjects with an average age of 37.2 years(SD=8.28), weight of 69.6 kg(SD=10.56) and a height of 171 cm(SD=4.93) were recruited for this study. Ten males walked on a treadmill wearing four different shoes. Foot pressure data was collected using a Pedar-X mobile system(Novel Gmbh., Germany) operating at the 1000 Hz. Surface EMG signals for tibialis anterior, gastrocnemius, vastus lateralis and biceps femoris were acquired at 1000 Hz using Noraxon TeleMyo DTS system(Noraxon Inc., USA). Foot pressure and leg muscle fatigue were measured and calculated during walking. The results are as follows: After walking 60 minutes, Type A showed a lower MPF. MPF values were significantly different from each muscle(p】

Biomechanical analysis of smart walking shoe sending movement information to display device by radio communication

The purpose of this study was to find the difference in foot pressure patterns when wearing smart walking shoes. Foot pressure measurement is an established tool for the evaluation of foot function [1]. These measurements assess the effect of structural changes, which may occur as a complication of pathologies such as diabetes, and therefore have been suggested as one of the key tools in ulcer risk estimation [2]. The subjects who took part in the test consist of 5 elderly people and 5 young people. The physical features of the elderly people that were recruited for the study are shown below: 5 healthy male subjects (elderly people) with an average age of 62.0 yrs (S.D 1.0 yrs), weight of 69.4 kg (S.D 10.0 kg), height of 168.8 cm (S.D 5.3 cm) and a foot size of 270.0 mm (S.D 0.0 mm). 5 healthy male subjects (young people) with an average age of 27.2 yrs (S.D 4.1 yrs), weight of 75.2 kg (S.D 4.6 kg), height of 175.4 cm (S.D 4.0 cm) and a foot size of 270.0 mm (S.D 0.0 mm). Ten males (5 elderly people, 5 young people) walked on a treadmill wearing three different shoes. Foot pressure data (Contact areas, Maximum forece, Peak pressure, Maximum mean pressure) was collected using a Pedar-X mobile system (Novel Gmbh., Germany) operating at the 1,000 Hz. Figure 1 Type A: development shoes, Type B: control shoes, Type C: smart walking shoes Table 1 Result of Foot Pressure The results are as follows: 1. Young people In comparison with the Type B (control shoes): 1) Type A (development shoes) a)The contact area of foot (Total) by increased 8.36%, forefoot (M1) by increased 8.95%, midfoot (M2) by increased 12.18% and rearfoot (M3) by increased 4.48%. b)The maximum force of foot (Total) by decreased 4.02%, rearfoot (M3) by decreased 6.39%, while the maximum force of forefoot (M1) by increased 2.48% and midfoot (M2) by increased 17.52%. c)The peak pressure of foot (Total) by increased 2.28%, forefoot (M1) by increased 6.19%, while the peak pressure of midfoot (M2) by decreased 2.91% and rearfoot (M3) by decreased 13.69%. d)The maximum mean pressure of foot (Total) by decreased 12.74%, forefoot (M1) by decreased 6.90%, midfoot (M2) by decreased 2.79% and rearfoot (M3) by decreased 11.18%. 2) Type C (smart walking shoes) a)The contact area of foot (Total) by increased 7.96%, forefoot (M1) by increased 8.90%, midfoot (M2) by increased 11.81% and rearfoot (M3) by increased 3.50%. b)The maximum force of foot (Total) by decreased 5.27%, forefoot (M1) by decreased 0.67% and rearfoot (M3) by decreased 5.67%, while the maximum force of midfoot (M2) by increased 23.55%. c)The peak pressure of foot (Total) by decreased 6.70%, forefoot (M1) by decreased 3.35% and rearfoot (M3) by decreased 10.54%, while the peak pressure of midfoot (M2) by increased 2.19%. d)The maximum mean pressure of foot (Total) by decreased 10.97%, forefoot (M1) by decreased 7.62%, midfoot (M2) by decreased 1.15% and rearfoot (M3) by decreased 8.02%. 2. Elderly people In comparison with the Type B (control shoes): 1) Type A (development shoes) a)The contact area of foot (Total) by increased 8.09%, forefoot (M1) by increased 5.47%, midfoot (M2) by increased 22.66% and rearfoot (M3) by increased 3.21%. b)The maximum force of foot (Total) by decreased 2.13%, forefoot (M1) by decreased 3.53% and rearfoot (M3) by decreased 9.85%, while the maximum force of midfoot (M2) by increased 41.32%. c)The peak pressure of foot (Total) by decreased 11.02%, forefoot (M1) by decreased 11.24%, midfoot (M2) by decreased 2.81% and rearfoot (M3) by decreased 18.85%. d)The maximum mean pressure force of foot (Total) by decreased 10.60%, forefoot (M1) by decreased 7.05% and rearfoot (M3) by decreased 14.42%, while the maximum force of midfoot (M2) by increased 3.04%. 2) Type C (smart walking shoes) a)The contact area of foot (Total) by increased 7.08%, forefoot (M1) by increased 5.62%, midfoot (M2) by increased 17.14% and rearfoot (M3) by increased 3.12%. b)The maximum force of foot (Total) by decreased 1.47%, rearfoot (M3) by decreased 7.37%, while the maximum force of forefoot (M1) by increased 0.19% and midfoot (M2) by increased 24.15%. c)The peak pressure of foot (Total) by increased 0.03%, forefoot (M1) by increased 0.74%, while the peak pressure of midfoot (M2) by decreased 15.51% and rearfoot (M3) by decreased 14.73%. d)The maximum mean pressure of foot (Total) by decreased 8.95%, forefoot (M1) by decreased 5.62%, midfoot (M2) by decreased 6.30% and rearfoot (M3) by decreased 11.82%. As a result of analysis, it has been found that Type A and Type C have lower foot pressure (Total, M3) than Type B. Also, Type A and Type C show superior performance compared to Type B in all mask at contact area. Type A and Type C shoes will be used to reduce foot pressure and increase comfort and fitting.

Effects of the toe spring angle of bobsleigh shoes on bobsleigh start time and forefoot bending angle in preparation for the 2018 Pyeongchang Winter Olympics

angle in preparation for the 2018 Pyeongchang Winter Olympics Seungbum Park*, Kyungdeuk Lee, Daewoong Kim, Junghyeon Yoo, Jaemin Jung, Kyunghwan Park, Sungwon Park and Jinhoon Kim Footwear Industrial Promotion Center, Busan, Republic of Korea; Footwear Biomechanics Team, Busan, Republic of Korea; Footwear Industrial Promotion Center, Busan Economic Promotion Agency, Footwear Biomechanics Team, Busan, Republic of Korea; TrekSta Inc, R&D Center, Busan, Republic of Korea

Analysis of plantar pressure during climbing for the development of sports climbing shoes

Gaining better insight into the loading volume and intensity of runners outside of the lab will allow progress in academia and industry. Within academia, monitoring the load experienced during every day activities will improve the quality of longitudinal research studies addressing overuse injury development. This is because real world load patterns prior to the onset of the injury could be analysed and the influence of activity related fatigue could be considered. The footwear industry could use SEF information to optimize footwear selection or customization for an individual. SEF might also give feedback to the customer with respect to a less injury-risky movement behaviour. The results of the present study provide evidence that the prediction based estimation of loading parameters based on machine learning algorithms might be a feasible approach for the prediction of loading parameters. Nonetheless, prediction quality needs to be further improved, in particular for loading parameters outside of the sagittal plane. This might be achieved by using more sophisticated machine learning techniques and/or by adding sensor information from other locations or different sensors, e.g. gyroscopes or pressure sensors.

An analysis of functional insole on foot pressure distribution of shape memory material combinations

The purpose of this study was to analyze foot pressure distribution of shape memory materials functional insole. Comfort is an important aspect for footwear and insole. Footwear and insole comfort has an influence on injury [1,2]. The development of new materials is considered as the important point for manufacturing functional insole [3,4]. Ten healthy male (mean height: 174.7±4.0 cm, mean body mass: 71.0±8.0 kg, mean age 23.9±0.3 yrs.) were participated in this study. All subjects were free of lower extremity pain, history of serious injuries or operative treatment or subjective symptoms interfering with walking. Each subjects foot was pre-screened by Podoscopy (Alfoots, Korea) to see if they had any foot abnormalities. The subjects were required to normal walking (4.2km/h) for treadmill. Each subjects was seven different insole type (A ~G type, figure ​figure1)1) during walking. The PEDAR®-X insole system (Novel GmbH, Germany) was used to measure the foot pressure and force. Pressure distribution data (peak pressure, maximum mean pressure) was collected with pressure device at a sampling rate of 100Hz. The feet were divided into six regions: foot (Total), lateral forefoot (M1), medial forefoot (M2), midfoot (M3), lateral rearfoot (M4), and medial rearfoot (M5). Figure 1 Tested seven types insoles (L-R): Type A ~ G. N: normal material, S1: low hardness shape memory material, S2: high hardness shape memory material, P1: low hardness Poron® material, P2: high hardness Poron® material. Comparison of foot pressure is show in figure ​figure2.2. In the midfoot (M3) area, a significant different was found between insoles in peak pressure and maximum mean pressure. The type F and G insoles decreased the peak pressure and maximum mean pressure. Figure 2 Comparison of foot pressure of the seven types insoles.

Biomechanical analysis of marathon shoes applied to NESTFIT technology

The purpose of this study was to analyze foot pressure distribution of marathon shoes to which NESTFIT Technology was applied. As for marathon, shoes play a vital role in shortening records. However, they also might become a main factor of injury during longdistance running. This study will examine foot pressure distribution effects of marathon shoes during longdistance running, which have been developed by measuring Korean shoe lasts. The methods of this study can be explained as below. Firstly, ten healthy males were picked as subjects to participate in this study. 10 healthy male subjects with an average age of 22.3 years (SD=0.5), weight of 71.5 kg (SD=6.0) and height of 173.1 cm (SD=4.3) were recruited for this study. Secondly, the one equipment used for the study consist of af oot pressure device from Pedar-X, Germany and a treadmill from Pulse fitness, UK. Thirdly, the testing procedures involve each subject to test three different shoes by having running trials on a treadmill at a constant speed of 12.0km/hour. The pressure distribution data (contact area, maximum force, maximum peak pressure, maximum mean pressure)

Plantar pressure distribution during treadmill walking in comfort shoes with PLA(Poly Lactic Acid) resins

In the framework of environmentally friendly processes and products, poly lactic acid(PLA) represents the best polymeric substitutes for various petropolymers because of its renewability, biodegradability, biocompatibility and good thermomechanical properties [1]. The purpose of this study was to analyze foot pressure distribution of PLA materials in functional shoes. Comfort is an important aspect in footwear. Footwear comfort has an influence on

Kinetics and kinematics effects of variable stiffness shoe on lower extremity

activity, so optimal ankle stiffness may not have been achieved, hence RE was similar to SH and worse than BF. Shorter strides without cushioning or heightened proprioception produce less stability and may not be beneficial to performance. The results support suggestions that the initial foot angle (or footstrike) does not directly affect RE (Perl et al. 2012) or result from a change in heel lift, but rather from shorter stride lengths. This appears to be more influential than heightened proprioception. Whilst BF running offers performance benefits by improving RE, this appears to be done at the expense of increased injury risk. The heightened proprioception increases ankle stiffness and enables runners to adopt shorter SLs more economically.