Quantifying the effectiveness of static and dynamic insoles in reducing the tibial shock experienced during walking.

Many individuals work in jobs that require them to spend much of their day walking. There is evidence to suggest that shoe insoles may reduce the lower extremity discomfort for these workers. This study compared the effects of static and dynamic shoe insoles on lower extremity forces when walking at different speeds. Tibial acceleration (a.k.a. tibial shock) was assessed bilaterally in 30 participants who walked in both athletic shoes and work boots without any additional insole, with additional static insoles, and with additional dynamic insoles. The participants walked a prescribed course at a "slow", "normal", and "fast" pace. With both shoe types, there were significant reductions in tibial shock values when insoles were used. With the work boots, the dynamic insole further reduced tibial shock relative to the static insole. The significant interactions show that the differences between insole conditions become greater with faster walking speeds.