Functional evaluation of air insoles and methodology for determining the optimal thickness according to weight group

This study evaluates the effectiveness of four air insoles with varying thicknesses and one typical insole by measuring the total muscle activity, total muscle fatigue, left/right foot pressure symmetry ratio, and subjective fatigue among participants in three weight groups (<50, 50–70, and >70 kg). To minimize cumulative fatigue among participants, only one type of insole was tested per day. The 0.6- to 1.0-cm thick air insoles have a positive impact on muscle activity, muscle fatigue, and subjective fatigue compared to the typical 0.8-cm insoles. In terms of subjective fatigue, the 0.6-, 1.0-, and 1.2-cm air insoles yielded lower fatigue levels in the <50 kg group; however, the 50–70 kg group exhibited the lowest fatigue level when wearing the 0.8-cm air insoles. The proposed methodology may provide reference for optimal air insole thickness for users of varying weight ranges.