Which statement best describes the Russian current?

• A. Yakov Kots
• B. A sine wave current with 2500 pps carrier frequency (pulse duration 400 usec)
• C. Modulated at burst period 10 msec and inter-burst interval 10 msec; burst frequency 50 bps
• D. Elicited muscle forces greater than 100% MVC

Answer: (B)

The main idea behind the Russian current is a medium‑frequency carrier delivered in bursts to create strong, controlled muscle contractions with good comfort. The best description is a sine-wave current at a 2,500 Hz carrier that is delivered in bursts, with short pulses within those bursts. The 400 microsecond pulse width specifies how long each individual pulse lasts inside the high‑frequency wave, which is the defining feature you feel as a rapid, repeating sequence rather than a single low‑frequency pulse. This combination—high-frequency carrier and short intra-burst pulses—captures how Russian current is structured to reach deeper muscles with less skin irritation.

The other statements miss this core waveform description. One mentions a person’s name rather than the electrical pattern. Another describes the timing of bursts (on and off intervals) without tying it to the high‑frequency carrier and pulse width that characterize the method. The last implies a muscle force exceeding MVC, which isn’t a defining property of the current’s description and isn’t how stimulation is interpreted clinically.