Therapeutic Currents: Russian Current

Foundations of Clinical Electrotherapy - Chapter 9: Therapeutic Currents

Introduction

Electrostimulation (ES) requires selecting the appropriate current waveform to achieve the desired response (e.g., muscle contraction, sensory stimulation).
Modern devices offer multiwaveform options derived from direct current (DC), alternating current (AC), or pulsed current, each with different parameters.
Inconsistent terminology and marketing can cause confusion; waveforms should be described by specific parameters rather than trendy names.

Medium Frequency Current

Falls within the range of 1000 to 10000 Hz.
Advantages:
- Greater penetration.
- High tolerance and comfort.
- Suitable for pain and muscle stimulation.
- Low skin resistance.
Types:
- Rebox-type current: Non-invasive transcutaneous application for acute and chronic pain, immobility, musculoskeletal, and neurological disorders.
- Russian current: Medium frequency current delivered in alternating pulses or bursts.
- Interferential therapy.

Russian Current

Widely recognized waveform, named after Dr. Yakov Kots, who popularized it in the 1970s.
Kots claimed strength gains of up to 40% in elite Russian Olympic athletes.
These claims were significant because they represented gains in healthy individuals.
Russian current is a variation of alternating current.
Conventional Russian current is a 2,500 Hz alternating sinusoidal current delivered in short bursts (burst modulation).

Parameters

Bursts are delivered at 50 bursts per second.
Burst duration: 10 msec.
Inter burst interval: 10 msec.
Carrier frequency: 2,500 Hz (frequency of the sine wave interrupted into bursts).
Within each 10-msec burst, there are 25 complete cycles of AC.
Treatment frequency: 50 Hz with a 400 \mu sec cycle duration (1/2,500 cycles per second), suited for activating skeletal muscle.
Original Russian protocol: 10-second contraction time and 50-second off-time for 10 repetitions.
Duty cycle:
- Russian current has a 50% relative duty cycle (burst duration equals inter burst interval).
- Actual duty cycle of a 10-second on/50-second off protocol is 16.7% (\frac{10}{60} \times 100%).
The 50% relative duty cycle and 400- \mu sec pulse duration are benefits of burst-modulated AC for muscle strengthening.

Note

The evidence for burst modulated AC (Russian current) versus other waveforms for muscle strengthening remains inconclusive.
Ward (2009) reported that evidence ranges from a single case study showing increased strength to evidence of no increase in strength.
Recent studies suggest:
- A 1,000-Hz carrier frequency elicited greater torque than 2,500 Hz.
- Burst durations of 2 to 5 msec may be better suited for muscle stimulation compared to 10-msec.
Bellew et al. (2012 and 2013) supported Ward's findings, suggesting lesser carrier frequency and duty cycle elicited significantly greater muscle force.
Aussie current:
- A variation on Russian current, available in the United States.
- 1,000-Hz burst-modulated AC current delivered in 4-msec bursts.
- Greater torque production and decreased rate of muscle fatigue compared to conventional Russian current.

Characteristics Summary

Medium-frequency current.
Intermittent alternating sinusoidal current with a carrier frequency of 2500 Hz.
Sinusoidal waveform delivered in bursts or series of pulses.
Medium frequency, burst alternating current.

Waveform Parameters

Carrier Frequency: 2500Hz (2.5 KHz).
Waveform: Polyphasic sinusoidal waveform.
Current Amplitude: Maximum 100mA, clinically used at 70mA.
Bursts Frequency: 50 Hz.
Burst Duration: 10ms
On/Off Ratio: Ratio of stimulation (contraction) time to no stimulation (no contraction) time, set as 10ms:10ms.
Duty cycle: The proportion of on time to the summation of both the on and off time expressed as percentages, (e.g. \frac{10}{(10+10)} \times 100 = 50%).
Ramp-Up and Down: Set for 1-2 seconds to allow gradual increase of intensity, mimicking natural muscle contraction.

Training Protocol

Popular clinical protocol: (10/50/10)
- 10 seconds: Muscle contraction.
- 50 seconds: Off time (no contraction).
- Repeated for 10 cycles.
Duration and frequency of treatment: 10 minutes, once daily per week for several weeks (3-6 months).
Electrode placement: Parallel to the direction of muscle fibers.
Time delay switch:
- Synchronous mode: Both channels triggered simultaneously (no time delay set).
- Reciprocal mode: Channel 1 is on then channel 2 is off (time delay equal to time of channel 1).
- Overlapping mode: Channel 2 overlaps with on time and off time of channel 1 (time delay more than 1 sec but less than on time of channel 1).

Physiological Effects

Depend on the total number of bursts delivered per second.
Depolarization:
- Sensory nerve fibers: Moderate prickling sensation.
- Motor nerve fibers: Tetanic muscle contraction.
Painless contraction due to sensory nerve block of pain gate.
Allows use of high amplitude.
Stronger contraction than voluntary control.
- Voluntary contraction: Motor units recruited asynchronously.
- Electrically evoked muscle contraction: Motor units fire synchronously.
High level electrically evoked muscular contraction
Contraction against external load
Muscle strengthening

Indications

Strengthening the muscular system of healthy and athletic persons (as introduced by Kots in 1977).
Post-knee ligaments surgery
Post arthroscopic knee surgery
Following ligament sprain (↑ quads force during immobilization).
Post casting
Muscle spasm

Contraindications

Over the anterior cervical area
Over the lumbar or abdominal area during pregnancy
Over hemorrhagic area
Over neoplastic area
Over metallic and electronic implant
Over area of impaired skin sensation

Term 1: What is the basic principle of electrostimulation (ES)?
Definition 1: Electrostimulation requires selecting the appropriate current waveform to achieve the desired response.
Term 2: What are the types of current waveforms used in modern electrotherapy devices?
Definition 2: Direct current (DC), alternating current (AC), or pulsed current.
Term 3: What are the advantages of medium frequency current?
Definition 3: Greater penetration, high tolerance and comfort, suitable for pain and muscle stimulation, and low skin resistance.
Term 4: What is Rebox-type current used for?
Definition 4: Non-invasive transcutaneous application for acute and chronic pain, immobility, musculoskeletal, and neurological disorders.
Term 5: What is Russian current?
Definition 5: Medium frequency current delivered in alternating pulses or bursts.
Term 6: Who popularized Russian current?
Definition 6: Dr. Yakov Kots in the 1970s.
Term 7: What is the carrier frequency of conventional Russian current?
Definition 7: 2,500 Hz.
Term 8: What is the burst rate in Russian current?
Definition 8: 50 bursts per second.
Term 9: What is the burst duration in Russian current?
Definition 9: 10 msec.
Term 10: What is the inter burst interval in Russian current?
Definition 10: 10 msec.
Term 11: What is the treatment frequency of Russian current and why is it suited for activating skeletal muscle?
Definition 11: 50 Hz with a 400 \mu sec cycle duration (1/2,500 cycles per second).
Term 12: What is the original Russian protocol?
Definition 12: 10-second contraction time and 50-second off-time for 10 repetitions.
Term 13: What is the relative duty cycle of Russian current?
Definition 13: 50% (burst duration equals inter burst interval).
Term 14: What is the actual duty cycle of a 10-second on/50-second off protocol?
Definition 14: 16.7% (\frac{10}{60} \times 100%).
Term 15: What do recent studies suggest about optimizing carrier frequency and burst durations for muscle stimulation?
Definition 15: A 1,000-Hz carrier frequency elicited greater torque than 2,500 Hz, and burst durations of 2 to 5 msec may be better suited for muscle stimulation compared to 10-msec.
Term 16: What is Aussie current?
Definition 16: A variation on Russian current with a 1,000-Hz burst-modulated AC current delivered in 4-msec bursts.
Term 17: What are the advantages of Aussie current over conventional Russian current?
Definition 17: Greater torque production and decreased rate of muscle fatigue compared to conventional Russian current.
Term 18: What is the carrier frequency in Russian current?
Definition 18: 2500Hz (2.5 KHz).
Term 19: What is the waveform in Russian current?
Definition 19: Polyphasic sinusoidal waveform.
Term 20: What is the current amplitude typically used in Russian current therapy?
Definition 20: Maximum 100mA, clinically used at 70mA.
Term 21: What is the bursts frequency in Russian current?
Definition 21: 50 Hz.
Term 22: What is the burst duration in Russian current?
Definition 22: 10ms
Term 23: What is the on/off Ratio in Russian current?
Definition 23: Ratio of stimulation (contraction) time to no stimulation (no contraction) time, set as 10ms:10ms.
Term 24: What is the duty cycle in Russian current?
Definition 24: The proportion of on time to the summation of both the on and off time expressed as percentages, (e.g. \frac{10}{(10+10)} \times 100 = 50%).
Term 25: Why are ramp-up and ramp-down times used?
Definition 25: Set for 1-2 seconds to allow gradual increase of intensity, mimicking natural muscle contraction.
Term 26: What is a popular clinical protocol for Russian current?
Definition 26: 10 seconds: Muscle contraction; 50 seconds: Off time (no contraction); Repeated for 10 cycles.
Term 27: How should electrodes be placed during Russian current stimulation?
Definition 27: Parallel to the direction of muscle fibers.
Term 28: What is synchronous mode in Russian current?
Definition 28: Both channels triggered simultaneously (no time delay set).
Term 29: What is reciprocal mode in Russian current?
Definition 29: Channel 1 is on then channel 2 is off (time delay equal to time of channel 1).
Term 30: What is overlapping mode in Russian current?
Definition 30: Channel 2 overlaps with on time and off time of channel 1 (time delay more than 1 sec but less than on time of channel 1).
Term 31: What sensation is produced during sensory nerve fiber depolarization?
Definition 31: Moderate prickling sensation.
Term 32: What happens during motor nerve fiber depolarization?
Definition 32: Tetanic muscle contraction.
Term 33: How are motor units recruited during voluntary contraction?
Definition 33: Motor units recruited asynchronously.
Term 34: How are motor units recruited during electrically evoked muscle contraction?
Definition 34: Motor units fire synchronously.
Term 35: undefined
Definition 35: Strengthening the muscular system of healthy and athletic persons, post-knee ligaments surgery, post arthroscopic knee surgery,