the comparison of plantar pressure distribution and frequency content of selected muscles between hydrodynamic and typical sport shoe

This study aimed to investigate the comparison of plantar pressure distribution and muscle frequency between hydrodynamic and typical sport shoe. 12 healthy adult male were recruited for this experimental study. the special hydrodynamic shoe has an outer sole with a special pathway for the fluid. the typical sports shoe with ethylene-vinyl acetate soles was recruited for the comparison. plantar pressure distribution was measured using the pedar insole system and the results have 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 1000hz sampling rate. subjects randomly wore hydrodynamic and typical sports shoes, then walk through the end of the pathway for the five times at self-selected speed. the plantar area was divided into eight areas and plantar pressure variables were calculated in these areas. the onset and offset of muscle activation were calculated. the frequency variable includes mean and median frequency, the 99.5% frequency which contain 99.5% signal, and the bandwidth frequency was also calculated. paired -t test was used for statistical comparison (p<0.05). the results indicated that there are considerable pressure reduction in heel, fore foot and toe (p<0.05). however, there is no difference between the time and frequency content of muscle activity. based on the results, it seems that hydrodynamic shoes could an important effect on the reduction of plantar pressure without any change in muscle activity during the gait.