Effects of Training With High and Low-Frequency Electrical Stimulation on Muscle Contractile Properties in Rabbits

Controversy exists regarding the effects of different frequencies of ES on muscle contractile properties. The purpose of this study was to investigate the role of ES frequency on muscle contractile properties. Six male rabbits were divided into 2 groups (low and high-frequency ES training groups, stimulated by using 20 and 100 Hz respectively). They were trained by using surface ES on the gastrocnemius muscle 2 h daily, 5 days per week for 4 weeks. The twitch time to peak torque decreased in the high-frequency group and increased in the low-frequency group after ES training. The peak twitch torque, maximal tetanic contraction torque, and fatigue resistance all increased in both groups. According to the results, ES training with different frequencies may result in different effects on muscle phenotype transformation, whereas, increased muscle mass, muscle fiber density, new capillaries, and circulation might be effects of ES training common to different frequencies.