Effects of neuromuscular electrical stimulation and resistance training on skeletal muscle responses of elderly people

Aim: Resistance training (RT) has been shown to be effective to increase and to maintain strength in elderly people. Neuromuscular electrical stimulation (NMES) has been suggested as an alternative for people who have limited movement. The main purpose of this study was to compare the effects of NMES and RT on skeletal muscle responses of elderly people. Method: Twenty-nine elderly male volunteers (70 ± 5 years old) participated in this study. For 8 weeks, they performed a training protocol that was randomly assigned as two different groups: NMES (n = 19) and RT (n = 10). Before and after the training, measurements were made of their anthropometric parameters, functional capacity and strength capacity (maximum voluntary contraction, MVC; maximal voluntary isometric contraction, MVIC). The electromyography activity (EMG) of the vastus lateralis (VL) and vastus medialis (VM) muscles during isokinetic (180 s-1) and isometric maximal contractions were analysed in a subset of samples (n = 3, for both NMES and RT). The EMG signals were recorded using a 16-channel surface electromyography device (EMG 16, LISiN, Bioengineering Center, Polytechnic of Turin, Italy; sampling rate, 2048 Hz; common-mode rejection rate, 96 dB; gain, 2000; signal passing limit, ±5 V; software EmgAcq). Results: MVIC increased in both of the groups during these protocols. Other analyses are ongoing. Conclusion: NMES stimulation appears to be an alternative for counteracting the loss of muscular strength associated with sarcopenia in elderly male people when RT cannot to be performed.