Muscle damage induced by electrical stimulation

Abstract

Electrical stimulation (ES) induces muscle damage that is characterised by histological alterations of muscle fibres and connective tissue, increases in circulating creatine kinase (CK) activity, decreases in muscle strength and development of delayed onset muscle soreness (DOMS). Muscle damage is induced not only by eccentric contractions with ES but also by isometric contractions evoked by ES. Muscle damage profile following 40 isometric contractions of the knee extensors is similar between pulsed current (75 Hz, 400 μs) and alternating current (2.5 kHz delivered at 75 Hz, 400 μs) ES for similar force output. When comparing maximal voluntary and ES-evoked (75 Hz, 200 μs) 50 isometric contractions of the elbow flexors, ES results in greater decreases in maximal voluntary contraction strength, increases in plasma CK activity and DOMS. It appears that the magnitude of muscle damage induced by ES-evoked isometric contractions is comparable to that induced by maximal voluntary eccentric contractions, although the volume of affected muscles in ES is not as large as that of eccentric exercise-induced muscle damage. It seems likely that the muscle damage in ES is associated with high mechanical stress on the activated muscle fibres due to the specificity of motor unit recruitment (i.e., non-selective, synchronous and spatially fixed manner). The magnitude of muscle damage induced by ES is significantly reduced when the second ES bout is performed 2-4 weeks later. It is possible to attenuate the magnitude of muscle damage by "pre-conditioning" muscles, so that muscle damage should not limit the use of ES in training and rehabilitation.

Electrical stimulation for neuromuscular testing and training: state-of-the art and unresolved issues

“…The spatially fixed recruitment implies that the same motor units are repeatedly activated by the same amount of electrical current which, in turn, hastens the onset of muscle fatigue (as also discussed by Gondin et al 2011b). Such early occurrence of fatigue represents a major limitation of NMES, and could eventually play a role in NMES-induced muscle damage (Nosaka et al 2011). In order to maximize the spatial recruitment during NMES, thus minimizing the extent of muscle fatigue, it has been recommended to implement different expedients during a treatment session such as progressive increase in current intensity, alteration in muscle length, and displacement of active electrodes (Maffiuletti 2010).…”

“…Acute NMES use may cause profound muscle damage Nosaka et al (2011) reviewed the most recent evidence available for the muscle damage induced by NMES-evoked contractions, which resembles the type of damage produced by voluntary eccentric contractions, resulting in decreased maximal voluntary contraction (MVC) strength, increased circulating levels of muscle proteins and delayed onset muscle soreness. Muscle damage profile following NMES-evoked isometric contractions of the knee extensors is similar between different stimulation paradigms (pulsed vs. alternating current) for similar force outputs.…”

Effects of low-intensity concentric and eccentric exercise combined with blood flow restriction on indices of exercise-induced muscle damage

“…Indices of EIMD include swelling of the exercised limb, decreased range of motion (ROM), increased creatine kinase and myoglobin levels in the blood, decreased force production, and delayed-onset muscle soreness (DOMS) [2]. The severity of EIMD is related to the type [3] and intensity [4] of exercise.…”

A Pilot Study on Pain and the Upregulation of Myoglobin through Low-frequency and High-amplitude Electrical Stimulation-induced Muscle Contraction

“…Some studies on pain control through limiting of sympathetic nerves by electric and hot stimuli have been carried out11, 12 ) . It is known that applying improper electrotherapy can induce adverse effects, such as pain and muscle damage7, 13 ) . However, no study has examined the effect of electric stimuli on myoglobin itself.…”