Acute Effects of Whole-Body Electromyostimulation during a Single Maximal Strength Training Session

Abstract

Whole-body electromyostimulation (WB-EMS) training is effective in improving training adaptation. However, WB-EMS may have side effects and contraindications that can lead to excessive muscle damage and physiological impairment. This randomized crossover study aimed to analyze the acute effects of WB-EMS on muscle damage, autonomic modulation and performance during a single maximal strength session in physically active participants. Twenty healthy and physically active participants randomly performed three maximal strength training sessions (90% 1RM) consisting of bench presses and squat exercises, with a continuous stimulus, a coordinated stimulus with concentric and eccentric phases, and without WB-EMS. Data showed no significant differences between the trials for muscle damage (blood creatine kinase levels), lactate blood levels and performance after exercise. Likewise, the heart rate, blood oxygen saturation and the rate of perceived exertion were similar during exercise between trials. The heart rate variability analysis also showed a similar autonomic response among the trials. Training with WB-EMS seemed to be safe at the observed time intervals while offering a stimulus similar to regular training in physically active participants, regardless of the delivery of the electrical stimuli. More studies are needed to assess the effectiveness of WB-EMS in improving exercise adaptations during training programs.

Keywords: WB-EMS; acute effects; creatine kinase; heart rate variability; muscle damage.

Figure 1

(A): creatine kinase blood levels before, after and the day after the strength exercise session with a continuous stimulus (Cont WB-EM), coordinated stimulus with concentric and eccentric phases (Coord WB-EMS) and without whole-body electromyostimulation (Control). (B): lactate blood levels before and after the strength exercise session with the continuous stimulus (Cont WB-EM), coordinated stimulus with concentric and eccentric phases (Coord WB-EMS) and without whole-body electromyostimulation (Control). * Significantly different than the pre-exercise in all trials (p < 0.05).

Figure 2

(A): heart rate, (B): percentage of the oxygen saturation, and (C): rate of the perceived exertion during the bench press exercise with the continuous stimulus (Cont WB-EM), coordinated stimulus with concentric and eccentric phases (Coord WB-EMS) and without whole-body electromyostimulation (Control). (D): heart rate, (E): percentage of the oxygen saturation, and (F): rate of the perceived exertion during the squat exercise with the continuous stimulus (Cont WB-EM), the coordinated stimulus with concentric and eccentric phases (Coord WB-EMS) and without whole-body electromyostimulation (Control).