Spatial Distribution of Muscular Effects of Acute Whole-Body Electromyostimulation at the Mid-Thigh and Lower Leg—A Pilot Study Applying Magnetic Resonance Imaging

Abstract

Whole-body electromyostimulation (WB-EMS) is an innovative training method that stimulates large areas simultaneously. In order to determine the spatial distribution of WB-EMS with respect to volume involvement and stimulation depth, we determined the extent of intramuscular edema using magnetic resonance imaging (MRI) as a marker of structural effects. Intense WB-EMS first application (20 min, bipolar, 85 Hz, 350 µs) was conducted with eight physically less trained students without previous WB-EMS experience. Transversal T2-weighted MRI was performed at baseline and 72 h post WB-EMS to identify edema at the mid-thigh and lower leg. The depth of the edema ranged from superficial to maximum depth with superficial and deeper muscle groups of the mid-thigh or lower leg area approximately affected in a similar fashion. However, the grade of edema differed between the muscle groups, which suggests that the intensity of EMS-induced muscular contraction was not identical for all muscles. WB-EMS of the muscles via surface cuff electrodes has an effect on deeper parts of the stimulated anatomy. Reviewing the spatial and volume distribution, we observed a heterogeneous pattern of edema. We attribute this finding predominately to different stimulus thresholds of the muscles and differences in the stress resistance of the muscles.

Non-Athletic Cohorts Enrolled in Longitudinal Whole-Body Electromyostimulation Trials—An Evidence Map

“…The stimulus intensity of B-SES was consistently described as the maximum tolerable impulse intensity without pain (or discomfort); i.e., largely in line with the specification applied by WB-EMS. For both methods, acute stimulation effects on deeper muscle layers of the thigh and lower legs were reported [116,117]. We based our criteria of "safety" on missing adverse effects.…”

Revised contraindications for the use of non-medical WB-electromyostimulation. Evidence-based German consensus recommendations

“…Stimulus intensity of B-SES was consistently described as the maximum tolerable impulse intensity without pain (or discomfort); i.e., largely in line with the specification applied by WB-EMS. For both methods, acute stimulation effects on deeper muscle layers of the thigh and lower legs were reported ( 46 , 47 ). (2) As a key limitation of the systematic search, we cannot be sure that we identified all eligible articles, particularly due to poor information provided, difficulties in proper translation and, in some cases, missing author responses to our queries.…”

Influence of a long-term WB-EMS intervention on parameters of body composition and physical performance among individuals of different age decades between 19 and 81 years

“…Despite the low training duration and frequency, the effectiveness of WB-EMS has been extensively proven with regard to various aspects. Among other things, increases in muscular strength capabilities, enhancements in body composition, and increases in motor performance have been observed in individuals of different ages (Berger, Ludwig, Becker, Backfisch et al, 2020;Götz et al, 2022;Kemmler et al, 2022;Kemmler et al, 2021;Ludwig et al, 2020).…”