Abstract
The purpose of this study was to investigate the characteristics of the backward stepping reaction in the elderly by estimation of the acceleration of the center of foot pressure (COP) and its relationship with muscular strength. The study participants were 10 elderly people who were capable of executing a backward stepping movement and 13 young subjects. We measured the acceleration of COP at the time of the stepping movement by using a separation-type force plate. Furthermore, we estimated the muscular strength of the antigravity muscles using a hand-held dynamometer. By using multiple regression analyses, we found muscular strength was the explanatory variable of the acceleration of the COP. Muscular strengths of the peroneus longus and the quadriceps femoris were detected as significant explanatory variables in the elderly age group and that of gluteus medius was detected as a significant explanatory variable in the younger age group. These results demonstrate that there was a difference between the 2 age groups with regard to backward stepping reaction, and muscular strength was identified as one of the factors contributing to the backward stepping reaction in the elderly population.
