The Comparison of Plantar Pressure Distribution and Frequency Content of Selected Muscles Between Hydrodynamic and Typical Sport Shoe.

This study aimed to compare plantar pressure distribution and muscle frequency between hydrodynamic and typical sports shoes. Twelve healthy adult males participated in this experimental study. The hydrodynamic shoe features an outer sole with a pathway for fluid flow. The typical sports shoe with Ethylene-Vinyl Acetate soles was used for the comparison. Plantar pressure distribution was measured using the Pedar insole system, and the results were analyzed using Pedar-X software. Electrical muscle activity of the Gastrocnemius, Soleus, Palmaris longus, and tibialis anterior were measured using the Myon electromyography system at a 1000Hz sampling rate. Subjects were randomly assigned to wear either hydrodynamic or typical sports shoes and walked through the end of the pathway five times at a self-selected speed. The plantar area was divided into eight regions, and plantar pressure variables were calculated within these areas. The frequency variable includes mean and median frequency, as well as the 99.5th percentile frequency, representing 99.5% of the signal. Additionally, the bandwidth frequency was calculated. Paired t-test was used for statistical comparison (p<0.05). The results indicated considerable pressure reduction in the heel, forefoot, and toe (P<0.05). However, there is no difference in the time and frequency content of muscle activity between conditions. Based on the results, it seems that hydrodynamic shoes could have an important effect on the reduction of plantar pressure without any change in muscle activity during the gait.