The instantaneous effects of generic foot arch support insoles on centre of foot pressure in various modes of static balance

Abstract

The purpose of this study was to investigate the effects of generic foot arch support insoles on the center of foot pressure in Double-Legs-Stance, Single-Right-Leg-Stance, Single-Left-Leg-Stance, Right-Tandem-Stance and Left- Tandem-Stance. Ten healthy adults (male=5, female=5) were recruited in this study. Subjects were tested with no insole (Insole-A) and three different design of insoles (Insole-B, C and D) in each type of standing mode. A pressure mapping sensor (25Hz) with 25 sensel per square inch spatial resolution and pressure measurement system software were used to collect the center of pressure movements. A non-parametric Friedman test with Wilcoxon singed-ranks post-hoc test were used to analyze the significant effects of the insole. There was significant differences in anteroposterior travelled distance across insole support types, χ2(3, N=10) = 9.120, p < 0.05 for Double-Leg-Stance. However post-hoc test indicates that no significant difference in between any paired of insoles. Significant differences were found in anteroposterior peak velocity across insole support types for Single-Right-Leg- Stance, χ2(3, N=10) = 8.567, p < 0.05. Post-hoc test indicates that there is a significant difference in anteroposterior peak velocity for the Insole-C and Insole-B, z = -2.550, p < 0.05, with lower peak velocity of center of pressure shift in Insole-C. There were no significant differences found in Single-Left-Leg- Stance and Right-Tandem-Stance across all types of insole support. The results of the Friedman test indicate that no significant differences exist in Right-Tandem-Stance across all types of insole sup-port. There were significant differences in mediolateral range, mediolateral travelled distance and mediolateral position standard deviation across insole support types with chi square, χ2(3, N=10) = 9.0, χ2(3, N=10) = 9.12, χ2(3, N=10) = 8.04, p < 0.05 respectively for Left-Tandem- Stance. This study concludes that the generic foot arch support insoles have no significant positive instantaneous effects on center of pressure measurement.