• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.395-409
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• 2017

Objective: The purpose of this study was to optimize the number and positions of foot pressure sensors using the reliability analysis of the center of pressure (COP) in smart shoes. Background: Foot pressure can be different according to foot region, and it is important which region of the foot pressure needs to be measured. Method: Thirty adults (age: $20.5{\pm}1.8years$, body weight: $71.4{\pm}6.5kg$, height: $1.76{\pm}0.04m$) participated in this study. The foot pressure data were collected using the insole of Pedar-X system (Novel GmbH, USA) with a sampling frequency of 100Hz during 1.3m/s speed walking on the treadmill (Instrumented treadmill, Bertec, USA). The intraclass correlation coefficients (ICC) were calculated between the COP positions using 4, 5, 6, 7, 8, and 99 sensors, while one-way repeated measure ANOVA was performed between the standard deviation (SD) of the COP positions. Results: The medio-lateral (M/L) COP position using 99 sensors was positively correlated with the M/L COP positions using 6, 7, and 8 sensors; however, it was not correlated with the M/L COP positions using 4 and 5 sensors during landing phase (1~4%) (p<.05). The antero-posterior (A/P) COP position using 99 sensors was positively correlated with the A/P COP positions using 4, 5, 6, 7, and 8 sensors (p<.05). The SD of the COP position using 99 sensors was smaller than the SD of the M/L COP positions using 4, 5, 6, 7, and 8 sensors (p<.05). Conclusion: Based on our findings, it is desirable to arrange at least 6 sensors in smart shoes. Application: The study of optimizing the number and positions of foot pressure sensors would contribute to developing more effective smart shoes using foot pressure technology.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.261-268
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• 2012

The purpose of this study was to qualitatively analyze pressure intensity and the center of pressure(COP) trajectory according to shoe type. Subjects were ten first-year female university students. The EMED-AT 25/D(Novel, Germany) was used to measure pressure intensity and COP trajectory. The COP Excursion Index(CPEI) was used for within subject test design. Independent variables were bare feet and six types of shoes. Dependent variables were center of pressure trajectory and pressure intensity. Barefeet and five toed shoes had a similar pressure intensity and COP trajectory. COP trajectory for all other shoe types showed a medial wobble at the heel. Pressure intensity for all other shoe types was related to the structure of the shoes. In conclusion, different shoe types can not only affect gait, but they can also influence foot deformities, pain, and dysfunction.

• PNF and Movement
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• v.22 no.1
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• pp.23-30
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• 2024

Purpose: Ankle instability is a common issue in both daily activities and sports, often leading to recurrent injuries. Elastic taping is a non-pharmacological intervention used to improve ankle stability. This study aimed to investigate the immediate effects of elastic taping on ankle stability, center of pressure (COP) movement, and foot pressure distribution. Methods: A single-group pre-posttest design was employed, with 30 participants included in the study. Plantar pressure and COP parameters were measured before and after the application of elastic taping. Taping was administered in three distinct patterns to enhance ankle stability. Results: Immediate effects of elastic taping were evident in COP parameters. Following taping application, there was a significant decrease in COP total displacement, COP area, and COP velocity. However, no significant changes were observed in plantar pressure parameters. Conclusion: The application of elastic taping in this study demonstrated immediate effects on ankle stability and COP parameters, indicating its potential as a viable intervention for improving balance. Further research with larger sample sizes and long-term follow-up is needed to elucidate the sustained effects of elastic taping on ankle stability.

• The Journal of Korean Physical Therapy
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• v.23 no.3
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• pp.1-5
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• 2011

Purpose: This study examined the relationship between the center of pressure (COP) displacement time during the stance phase and dynamic balance ability when older adults cross a 10 cm obstacle. Methods: Fifteen older adults were enrolled in this study (all ${\geq}65$ years of age). The F-scan was used to measure the COP displacement time when subjects cross a 10 cm obstacle, and the Dynamic gait index. Berg's balance scale and the Four square step test were used to measure dynamic balance ability. Results: The Dynamic gait index, Berg's balance scale and the Four square step test were correlated with each other. Dynamic balance ability was correlated with COP displacement time during the stance phase at an obstacle crossing in older adults. Conclusion: People with higher dynamic balance ability show a smaller COP displacement time during the stance phase at an obstacle crossing. Therefore, dynamic balance ability can be predicted by measuring the center of pressure displacement time.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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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.

• Journal of Korean Physical Therapy Science
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• v.31 no.3
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• pp.15-22
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• 2024

Background: This study aimed to investigate the immediate effects of Flexi-bar exercise on plantar pressure and Center of Pressure in a standing position. Design: Single group pre-post test design Methods: Thirty healthy adult participants aged 20 to 35 years old and no recent musculoskeletal injuries were included in this single-group pre-post design study. Plantar pressure and COP data were collected using the WinTrack system before and after Flexi-bar exercise. Participants performed Flexi-bar exercises in both anterior-posterior and lateral directions for 30 seconds each. Results: The results revealed significant changes in plantar pressure and COP after Flexi-bar exercise. The support area of the left foot significantly increased (p<0.05), and a significant decrease in mean pressure was observed in the right foot (p<0.05). The total COP path length and area significantly decreased (p<0.05). Furthermore, there was a significant decrease in COP velocity along the X and Y axes (p<0.05). These findings suggest that Flexi-bar exercise can enhance plantar pressure distribution and COP movement patterns, contributing to improved balance ability. Conclusion: Flexi-bar exercise, performed in a standing position, has the potential to improve plantar pressure and COP characteristics. This exercise may serve as a valuable tool for enhancing balance ability. Further research is needed to explore the long-term effects and sustainability of these improvements.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1722-1725
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• 2014

An experimental investigation of COP(center of pressure) was performed using FSR(force sensing resistor) and force plate. The FSR sensor system is used as effective device to detect the movement of human body in activities of daily living. It has been shown that the FSR provides the trajectories of COP with repeatability and reliability.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.4
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• pp.67-74
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• 2020

PURPOSE: The progression of the center of pressure (COP) velocity of the stance phase may have important roles for predicting gait speed in older adults with cognitive decline. This study was conducted to identify the correlation between gait speed and the velocity of COP progression during the stance phase in older adults with cognitive decline. METHODS: Forty adults aged 65 years or older (twenty participants without cognitive decline, 20 participants with cognitive decline) were recruited. The COP progression velocity was measured using an F-scan pressure-sensitive insole system. The stance phase was divided into four sub-stages. (loading response, mid-stance, terminal stance, and pre-swing). Gait speed, double support phase, and cadence were also measured. Correlations and multiple regression analyses were performed. RESULTS: Gait speed was associated with the COP progression velocity in midstance (r = .719, p < .05), cadence (r = .719, p < .05) and the COP progression velocity in loading response velocity (r = .515, p < .05) in older adults with cognitive decline. However, no correlation was found in older adults without cognitive decline. In multiple regression analysis using gait speed as a dependent variable, the COP progression velocity in midstance and cadence were significant predictors of gait speed, with the COP progression velocity being the most significant predictor. CONCLUSION: The COP progression velocity is an important factor for predicting gait speed in older adults with cognitive decline, suggesting that the cognitive function influences gait speed and the velocity of COP progression.

• Fashion & Textile Research Journal
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• v.15 no.4
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• pp.613-619
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• 2013

This study compares the gait characteristics of elderly women during barefoot walking and walking with sneakers. We measured foot angles, max foot pressure, peak plantar pressure of each plantar region, velocity of Center of Pressure(COP), and axis shifting of COP with an RS-scan system. Elderly women's foot angles were narrower when walking with sneakers than when barefoot walking. We found that the subtalar joint angle (representing ankle joint flexibility) affected walking stability. Regarding the peak plantar pressure of each foot region, pressures were high in the medial regions and the pressures greatly varied depending on the region measured during barefoot walking. The COP moved significantly faster when walking with sneakers than barefoot walking and suggests that elderly women walked faster in sneakers. Axis shifting of the COP decreased during walking with sneakers and indicated that gait balance improved when walking with sneakers. The findings of the present study can be utilized as foundational data for elderly women's gait characteristics as well as data for the production of functional footwear. Future research that focuses on various types of shoes, age groups, and gender are recommended for the development of more functional footwear for stable gaits.

• PNF and Movement
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• v.12 no.4
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• pp.201-207
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• 2014

Purpose: The purpose of this study was functional leg length inequality effect on COP(Center Of Pressure) and LOS(limits Of Stability) and EMG activation. Methods: The participants were consisted of fourteen. Subjects were distributed 2 groups; control group, leg length inequality ${\leq}3mm$, n=8), experimental group(leg length inequality${\geq}10mm$, n=8). The participants were measured leg length wearing comfortable clothes through tape measure method(TMM). All subjects was measured COP(Center Of Pressure), LOS(limits of stability) using by Balance Trainer BT4(HUR, Finland). Results: The results COP was not exist statistical significant differences(p>0.05). LOS was not exist statistical significant difference(p>0.05). Conclusion: The results was not statistical significant differences COP and LOS depending on Leg Length Inequality. But between experimental group and comparison group was exist mean differences on COP, LOS(COP:Ex.>Com, LOS:Ex.