Impacts of different types of insoles on postural stability in older adults

• Four different types of insoles were examined in terms of their effects on postural stability in older adults.
• Static postural stability was not affected by insoles.
• Cupped insoles improved dynamic postural stability.
• Rigid insole was associated with better dynamic postural stability compared to soft insoles.
• The findings can aid in better understanding the insole design features that could improve postural stability in older adults.

The objective of this study was to examine the effects of different types of insoles on postural stability in older adults. Four types of commercially available insoles were selected including the cupped insoles, textured insoles, rigid insoles, and soft insoles. The experiment included a static stance session and a walking session. In the static stance session, the participants stood upright on a force platform as still as possible, with feet together, arms by the side and looking straight ahead. The mean velocity of center-of-pressure time series obtained from the force platform was used to assess static postural stability. In the walking session, the participants walked on a treadmill at their self-selected comfortable speed for 4.5 min in each insole condition. Dynamic postural stability was assessed using the margin of stability. It was found that static postural stability was not affected by insoles, but cupped insoles improved dynamic postural stability, and rigid insole was associated with better dynamic postural stability compared to soft insoles. These findings can aid in better understanding the insole design features associated with improved postural stability in older adults.