Influence of transcutaneous electrical nerve stimulation on weight distribution in lower leg muscles

[Purpose] The purpose of this study was to compare the effects of transcutaneous electrical nerve stimulation (TENS), with and without visual input, on weight distribution following exercise-induced fatigue in the dorsiflexor and plantar flexor muscles of the ankle. [Subjects and Methods] This study had a cross-sectional design. Nineteen healthy adults (10 males, 9 females; mean age 21±0.8 years) were recruited to participate in a single group repeated measurements study lasting three days. On the first day, following exercise-induced fatigue, the standing position was maintained for 30 minutes, after which the postural sway was measured with eyes open (EO) and eyes closed (EC). On the second day, TENS was applied to the ankle dorsiflexors in the standing position for 30 minutes following exercise-induced fatigue. On the last day, TENS was applied to the plantar flexors, and the postural sway was measured with EO and EC following the same exercise-induced fatigue. [Results] On level terrain, with and without visual input, there was a significant difference between the baseline values and those following TENS on the tibialis anterior. On uneven terrain (simulated by a cushion), with and without visual input, there was a significant difference between the baseline values and those following TENS on the gastrocnemius. [Conclusion] Clinically, during walking on a flat surface for only a short period of time, TENS should be applied to the tibialis anterior. If walking training is performed on a variety of terrains for a longer time, TENS should be applied to the gastrocnemius.