The influence of instructions on the walking motion in elderly women : focusing on walking speed, plantar pressure and ankle motion

A study was conducted to analyze the effects of instructions on elderly women's walking speed, the pressure on their planta, and their ankle motion during walking. Compared with free walking, the subjects were given the following instructions : (1) to walk as fast as possible 'fast-walking'; (2) to walk with as long a stride as possible 'long-stride walking'; (3) to walk with the heels striking the ground first 'heel-strike walking'; (4) to walk with the upper limbs swinging forward and backward with a large amplitude 'arm-swing walking'. The subjects were nine healthy elderly women (73-95 years of age). Using a Parotec System (Paromed Co. Ltd.), the pressure on the planta was measured and images of the walking movements were analyzed using Winanalyze. Compared with free walking, the first peak value of the pressure on the planta and the pressure on the heels showed a significant increase when walking under instruction. It was understood that this was due to increased walking speed and strength of heel strike when the subjects were conscious of the walking motion. The increased walking speed depended on the expansion of each step length. It was also suggested that the smaller dorsiflexion of the ankle joint in these elderly women during free walking could be improved by using 'heel-strike' walking. When walking according to instructions, the walking ratio (step length/cadence) of the women was similar to that of normal adults except in the case of 'fast-walking'. It was suggested that 'heel-strike walking', 'long-stride walking' and 'arm-swing walking' were likely to maintain walking ability and also to maintain the fitness level of elderly women.