The Russian protocol is a modality of electrical stimulation that has been employed for muscle strengthening. It was originally developed for strengthening of Russian Olympic athletes by Yadou Kots. This type of electrical stimulation is a medium frequency polyphasic AC waveform with burst modulations. There are typically 50 bursts per second with 50 pulses per burst. The application is 10 seconds on, 50 seconds off, for a duration of 10 minutes. The intensity is adjusted to elicit a tetanic contraction and is usually uncomfortable to the patient. There are several studies to indicate that this protocol may have some benefit in muscle strengthening. However, there are studies which also indicate that adjustments can be made to the original work of Kots which may be more appropriate and comfortable.
Articles Refuting Russian Electrical Stimulation
In an article by Alex Ward, Electrical stimulation using kilohertz-frequency alternating current, the effects of burst-modulated alternated currents were reviewed. Russian current is a type of burst-modulated alternating current that has been claimed to be beneficial for muscle strengthening. A single case study demonstrated significant strength gains with this protocol; however, there was also one study did not demonstrate any strength gains. In the study reporting strength gains, the parameters were 2.5 kHz AC applied in 10 millisecond bursts with a frequency of 50 Hz and 10 seconds on followed by 50 seconds off. Later studies have shown that short duration bursts are more comfortable for the same force output. The author concluded that the parameters used for Russian protocol are suboptimal for strengthening. Parameters that might be more beneficial would include a shorter duration of 2-4 millisecond burst of kilohertz AC. The author recommends a frequency of 1 to 2.5 kHz with a burst duration of 2 milliseconds for maximum muscle torque production.
According to the article: The effect of duty cycle and frequency on muscle torque production using kilohertz frequency range alternating . by Ward et al. there are suggested optimal parameters for Russian e-stim when it comes to subject comfort and subject maximal torque production. In regards to maximal torque production, the article suggests the best results are seen with a duty cycle of 20% or less, as compared to the more commonly adhered to 50% duty cycle setting, which is popular in many clinics. When comfort is taken as priority a frequency of 2.5 kHz is optimal, but for maximum torque production, 1 kHz should be considered.
In the study, Effect of Burst Frequency and Duration of Kilohertz-Frequency Alternating Currents and of Low-Frequency Pulsed Currents on Strength of Contraction, Muscle Fatigue, and Perceived Discomfort, the authors set out to determine if Russian electrical stimulation elicited a greater strength of muscle contraction than low frequency pulsed currents (LPC). This study showed no difference in the force of the contractions elicited by the LPC or Russian stimulation but the LPC fatigued muscles less. This study also showed no difference in the amount of discomfort experienced by patients when using either the LPC or Russian stimulation.
Ward, A. R. (2009). Electrical stimulation using kilohertz-frequency alternating current. Physical therapy, 89(2), 181-90. doi:10.2522/ptj.20080060
Ward, A. R., Robertson, V. J., & Ioannou, H. (2004). The effect of duty cycle and frequency on muscle torque production using kilohertz frequency range alternating current. Medical engineering & physics, 26(7), 569-79. doi:10.1016/j.medengphy.2004.04.007
Laufer, Yocheved, and Michal Elboim. "Effect of Burst Frequency and Duration of Kilohertz-Frequency Alternating Currents and of Low-Frequency Pulsed Currents on Strength of Contraction, Muscle Fatigue, and Perceived Discomfort ." Journal of the American Physical Therapy Association. 88.10 (2008): 1167-76. Web. 2 Mar. 2012. <http://ptjournal.apta.org/content/88/10/1167.long>.
Articles Supporting Russian Electrical Stimulation
The study, Torque responses in human quadriceps to burst-modulated alternating current at 3 carrier frequencies, examined the effects of frequency of burst-modulated current on the electrically induced torque of the quadriceps femoris muscle. The researchers used three groups to compare frequencies of 2500 Hz, 3750 Hz, and 5000 Hz. It was found that the electrically induced torque measures of the 2500 Hz frequency group were significantly greater than the 3750 Hz and 5000 Hz groups. Clinically, this information can be used on healthy subjects who are able to tolerate high stimulation intensities. The 2500 Hz frequency is more beneficial in generating greater electrically induced torques which is useful if strengthening is the goal of therapy.
In the article Interferential and burst-modulated biphasic pulsed currents yield greater muscular force than Russian current, by Bellew et al. Russian current was compared to interferential and burst-modulated biphasic pulsed currents to determine which method of electrical stimulation could produce the most amount of muscle force/torque by eliciting knee extension. The parameter of pulse duration was kept constant with each method, with a setting of 200 microseconds. Russian was delivered at 2500 Hz, burst modulated at 50 Hz, using 10msec burst duration and 10msec interburst interval. Biphasic pulsed was a symmetrical biphasic square wave delivered in bursts at 50 Hz. Quad IFC was delivered using currents of 2500 and 2550 Hz, yielding a 5050 Hz beat frequency. Treatments were administered 1 week from each other, and performed using optimal electrode placement. Results were compared with each healthy subjects’ previously recorded maximal voluntary isometric contraction (MVIT), showing that biphasic pulse, interferential, and Russian elicited 62.5%, 66.1%, and 35.8% of MVIT respectively. Therefore using the same pulse duration, Russian elicited significantly less torque and muscle force than biphasic pulsed, and interferential treatments.
In the article, Strength Changes in the Normal Quadriceps Femoris Muscle as a Result of Electrical Stimulation, the authors set out to find if Russian electrical stimulation alone could increase muscle strength. They used three experimental groups: a control group which did not exercise, a group that did an isometric workout, and a group that received Russian electrical stimulation. This study found that both the isometric and the electrical stimulation groups had a 2% increase in strength compared to the control group after a 5 week long program.
Parker, M. G., Keller, L., & Evenson, J. (2005). Torque responses in human quadriceps to burst-modulated alternating current at 3 carrier frequencies. The Journal of orthopaedic and sports physical therapy, 35(4), 239-45. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15901125
Bellew, J. W., Beiswanger, Z., Freeman, E., Gaerte, C., & Trafton, J. (2011). Interferential and burst-modulated biphasic pulsed currents yield greater muscular force than Russian current. Physiotherapy theory and practice. doi:10.3109/09593985.2011.637286
Laughman, R. Keith, James Youdas, Tom Garrett, and Edmund Chao. "Strength Changes in the Normal Quadriceps Femoris Muscle as a Result of Electrical Stimulation." Journal of the American Physical Therapy Association. 63.4 (1983): 494-5. Web. 2 Mar. 2012. <http://www.physther.net/content/63/4/494.full.pdf>.
Angie M., Luke G., and Ethan Q.
Angie M., Luke G., and Ethan Q.