The Relationship of PCI to Ambulatory Speed in Healthy Adult Females

Abstract

Ten healthy adult female subjects were asked to perform randomly one of five different ambulatory tasks, and their Physiological Cost Indexes (PCI) were measured 3 min after the tasks in order to investigate the relationship between ambulatory speed to PCI. The results revealed that it was not Mode C (comfortable walking speed), but Mode S (slow walking speed), which yielded the lowest, PCI 0.223 ± 0.09 bts/m at an average ambulatory speed of 59.3 ± 9.0 m/min. It was possible to approximate the relationship between PCI and ambulatory speed for both individual subjects and for the group as a whole with a quadratic polynomial expression. The relationship of actual PCI values to predicted PCI values showed a clear linear regression. The results obtained demonstrated the possibility of accurate prediction of PCI scores for randomly assigned ambulatory speeds.