Review of the evidence on the use of electrical muscle stimulation to treat sarcopenia

Electrical muscle stimulation (EMS) has been shown to increase muscle strength and mass, suggesting that it can be used for the treatment of sarcopenia. We herein present a detailed review of the physiological changes induced by EMS. Only human experimental and clinical studies were selected as reference articles for this review. Low-frequency stimulation appears to have greater effects on strengthening, while high frequency favors an increase in muscle mass. EMS also promotes compositional changes of the muscle fibers and improvements in the oxidative enzymatic activity and glucose uptake. Considering that structural changes towards type II muscle fibers and their motor units have an important role in the loss of muscle strength and that the response to muscular training is based on the capacity to increase muscle activation, an intervention protocol using EMS should focus on stimulating type II muscle fibers, rather than on inducing muscle hypertrophy.