LAUSR

CONTEXT Neuromuscular electrical stimulation (NMES) is widely used to induce muscular strength increase, however, no study has compared Russian current (RC) with Pulsed current (PC) effects after a training program. OBJECTIVES We studied the effects of different neuromuscular electrical stimulation (NMES) currents, Russian current (RC) and Pulsed current (PC) on the neuromuscular system after a six-week training period. DESIGN Blinded randomized controlled trial. SETTING Laboratory. PATIENTS Twenty-seven male soccer players (22.2±2.2 years, 74.2±10.0 kg, 177±0 cm, BMI: 23.7±2.9 kg/cm for the control group, 22.1±3.1 years, 69.7±5.7 kg, 174±0 cm, 23.0±2.5 kg/cm for the PC group, and 23.0±3.4 years, 72.1±10.7 kg,175±0 cm, 23.5±3.4 kg/cm for the RC group) were randomized into three groups: 1) control group, 2) RC (2500 Hz, burst 100 Hz, phase duration 200 μs), and 3) PC (100 Hz and 200 μs). Intervention: The experimental groups trained for six weeks, with three sessions per week with NMES. MAIN OUTCOME MEASURES Maximal voluntary isometric contraction (MVIC) and evoked torque, muscle architecture, sensory discomfort (VAS), and electromyographic activity (EMG) were evaluated before and after the six-week period. RESULTS Evoked torque increased in the RC (169.5±78.2 %, p<0.01) and PC groups (248.7±81.1 %, p<0.01). Muscle thickness and pennation angle increased in the RC (8.7±3.8 % and 16.7±9.0%, p<0.01) and PC groups (16.1±8.0 % and 27.4±11.0 %, p<0.01). The PC demonstrated lower values for VAS (38.8±17.1 %, p<0.01). There was no significant time difference for MVIC and RMS (root mean square) values (p>0.05). For all these variables, there was no difference between the RC and PC (p>0.05). CONCLUSION Despite the widespread use of RC in clinical practice, RC and PC training programs produced similar neuromuscular adaptations in soccer players. Nonetheless, as PC generated less perceived discomfort it could be preferred after several training sessions.