Relationship between Functional Reach test and the displacement and sway of center of foot pressure

Abstract

The purpose of this study was to investigate the relationship between Functional Reach test (FRT) distance and displacement of the center of foot pressure. We enrolled 33 healthy young women and assessed FRT distance, anterior displacement of the center of foot pressure (COP-A), total length of body sway in the maximal reach position,rectangular area in the maximal reach position, and postural stability index (PSI) using a forceplate. PSI was calculated using the following equation: PSI = (FRT distance)2/rectangular area. The correlation between FRT distance and COP-A was 0.46. No correlation between FRT distance and PSI was detected. These results suggest that FRT distance is a weak measure of stability limits and dynamic balance.