Background: Long-distance walking is a convenient way for prompting physical activity of elderly people. However, walking ability declines with aging.

Research question: This study assessed if silicone insoles with heel lifts (named here the prescribed insoles) could facilitate long-distance walking of older adults.

Methods: Fifteen adults aged over 65, who did not have obvious lower-limb problems, walked on a treadmill for totally 60 min in two separate walking sessions: 1) with the prescribed insoles, and 2) with original insoles of the standardized shoes. Gait tests using force plates and a motion analysis system, and subjective evaluation using visual analog and Borg's CR10 scales were conducted at different time points of the treadmill walking.

Results: Objective gait anaylsis showed that without using the prescribed insoles, there were significant reductions (p < 0.05) in stance time, vertical ground reaction force, ankle dorsiflexion angle and ankle power generation of the dominant leg after the 60-minute treadmill walk. Such significant reductions were not observed in the same group of subjects upon using the prescribed insoles. Meanwhile, significant improvements in subjective perception of physical exertion, pain and fatigue were observed.

Significance: Heel lifts and silicone insoles are generally used to relieve plantar pain and reduce strain of plantar flexors in patients. This study showed they might also be solutions to facilitate long-distance walking of older adults, an approach which could prompt their physical activity.