Determining the optimal frequency and current intensity of microcurrent stimulation for postural sway induction: A pilot study

Background: Maintaining postural balance is crucial for various daily activities, and the vestibular system plays a significant role in this process. Dysfunction in the vestibular system can result in impaired postural control and balance. Microcurrent therapy, which uses lower current intensities than traditional electrical stimulation methods, may offer a less painful alternative for vestibular system training. Objective: This pilot study aimed to investigate the effects of microcurrent stimulation on vestibular system training for posture control, with an emphasis on sway velocity and muscle activity, and to determine its optimal frequency and electric current intensity. Materials and methods: Twenty healthy young adults (mean age, 22.35 years; 76.5% female; mean body mass index, 24.5±3.5 kg/m²) participated in this study. Surface electromyography (EMG) of the tibialis anterior muscle and postural sway were measured during microcurrent stimulation at varying frequencies (0.5 Hz to 2.0 Hz) and intensities (50 μA to 400 μA) on the bilateral mastoid processes of 15 seconds each. The center of pressure displacement was recorded using a pressure platform, and muscle activity was assessed through EMG data. Results: The results showed that frequency did not significantly affect postural sway or muscle activity, whereas intensity did. Muscle activity was greatest at 1.5 Hz and 400 μA, and postural sway was most pronounced at 2.0 Hz and 400 μA. No adverse reactions were reported during or after the stimulation sessions. Conclusion: Microcurrent stimulation with optimal current and intensity may be a useful, non-invasive option for vestibular system training, particularly in populations where traditional electrical stimulation may cause discomfort. Further studies involving older adults and individuals with vestibular dysfunction are necessary to validate these findings.