Neuromuscular electrical stimulation of medium and low frequency on the quadriceps femoris

Abstract

Objective: The purpose of this study was to investigate the effects of neuromuscular electrical stimulation (NMES) in different frequencies on the quadriceps femoris. A randomized, controlled, blind cross-sectional study. Methods: Thirty subjects (12 men and 18 women), with an average age of 24.67 years, weight of 65.62 kg and height of 1.69 m were evaluated. Three random test conditions were applied: maximum voluntary isometric contraction (MVIC), maximum voluntary isometric contraction with medium frequency current (MVIC-MF) and maximum voluntary isometric contraction with low frequency current (MVIC-LF). Four MVICs were applied in each situation. The time between different isometric contraction types was 90 seconds while the time between the same conditions of contraction was 10 seconds. Results: Two-way ANOVA test showed that MVIC-MF had higher values for peak torque than MVIC-LF (p=0.02). Significant statistical results were found when comparing MVIC-MF and MVIC (p=0.03), but not for MVIC and MVIC-LF (p=0.52). Conclusion: Maximum voluntary isometric contraction associated with medium-frequency electrical stimulation was more effective than other NMES conditions.