Whole-Body Electrostimulation for Functional Recovery in Post-COVID Syndrome

Post-COVID syndrome, also referred to as long COVID, is characterized by the persistence of physical, functional, and cognitive symptoms following acute SARS-CoV-2 infection. Fatigue, reduced exercise tolerance, and limitations in activities of daily living are among the most frequently reported and disabling symptoms. Despite the growing number of affected individuals, evidence-based rehabilitation strategies for this population remain limited. Whole-body electromyostimulation (WB-EMS) is a non-pharmacological intervention that involves the simultaneous activation of large muscle groups through low-frequency electrical impulses delivered via surface electrodes integrated into a wearable suit. This technique allows muscle activation with low mechanical load and has shown potential benefits in improving physical performance and functional capacity in different clinical populations. However, its effectiveness in individuals with post-COVID syndrome has not yet been established. This study is designed as a randomized, double-blind, controlled pilot clinical trial to evaluate the feasibility, safety, and preliminary effectiveness of a WB-EMS-based intervention in people with post-COVID syndrome. Participants will be randomly assigned to one of two groups: an experimental group receiving active WB-EMS during the performance of functional activities, and a control group undergoing the same intervention protocol with minimal electrical stimulation, intended to act as a placebo condition. Both participants and outcome assessors will be blinded to group allocation. The intervention will consist of 12 supervised sessions, delivered once per week. Session duration will progressively increase from 10 to a maximum of 20 minutes, according to participant tolerance and protocol progression. Electrical stimulation parameters will be individualized and adjusted to achieve visible and tolerable muscle contractions in the experimental group, while remaining at non-therapeutic levels in the control group. Functional activities performed during the sessions will be selected and graded by qualified health professionals, with the aim of improving physical capacity, fatigue management, and independence in activities of daily living. Outcome measures will be collected at baseline (pre-intervention), immediately after completion of the intervention (post-intervention), and at a three-month follow-up. Primary outcomes include fatigue and functional capacity. Secondary outcomes include physical performance, muscle strength, and independence in activities of daily living. Safety outcomes and adverse events will be monitored throughout the study. As a pilot trial, this study aims to assess the feasibility and acceptability of the intervention, as well as to generate preliminary data on its potential therapeutic effects. The findings will inform the design of future larger-scale randomized controlled trials and contribute to the development of rehabilitation strategies for individuals with post-COVID syndrome.