Electrical stimulation is used extensively in physical therapy, and “Russian currents” have been advocated for use in increasing muscle force. This form of electrical stimulation seems to us to be the least understood in terms of physiological effects. Russian currents are alternating currents (AC) at a frequency of 2.5 kHz that are burst modulated at a frequency of 50 Hz with a 50% duty cycle. The stimulus is applied for a 10-second “on” period followed by a 50-second “off” or rest period, with a recommended treatment time of 10 minutes per stimulation session. This stimulation regimen (called the “10/50/10” regimen), applied once daily over a period of weeks, has been claimed to result in force gains.

Its capability of a high frequency (2500Hz) allows for deep muscle penetration, stimulation and intense muscle fiber contraction. It’s commonly used to relieve muscle spasms and to strengthen muscle power.