Abstract: To investigate the differences in lower limb electromyography between women with flat feet and normal feet during walking, and the effects of arch support insoles, a total of 14 female university students were recruited, with normal feet (N) wearing normal insoles and flat feet walking for 30 minutes on both feet wearing arch support insoles (FF+ASI) and normal insoles (FF), respectively. EMG signals of the rectus femoris (RF), anterior tibialis (AT), longissimus peroneus (PL), medial head of gastrocnemius (MHOG), and lateral head of gastrocnemius (LHOG) on the affected side were obtained using the Trigno wireless surface system, and Root Mean Square (RMS) were collected every 10 minutes. The differences in RMS between FF and N groups: LHOG was significant (P =0.021) and PL was highly significant (P =0.006) at the 1st minute; PL, MHOG and LHOG were highly significant (P =0), (P =0), (P =0.001) at the 10th minute; PL and LHOG were significant (P =0.022), (P =0.016) and MHOG was highly significant (P =0.006) at the 20th minute; PL was significant (P =0.023), MHOG and LHOG were highly significant (P =0.007), (P =0.007) at the 30th minute. The difference in RMS of FF+ASI compared to FF was highly significant only for PL at the 10th minute (P =0.006). In conclusion, women with flat feet showed higher levels of PL, MHOG and LHOG discharge than normal feet, resulting in more fatigue in the lower limb muscles. Fortunately,wearing arch support insoles relieved fatigue in MHOG, RF, AT and LHOG.

Key words: flat feet, arch support insoles, electromyography, female