Unfortunately, hospital-acquired weakness is highly prevalent among COVID-19 hospitalized patients, who often require prolonged bed-rest or paralytics for an extended period of time in order to maintain oxygenation. Prolonged bed rest has been associated with pronounced loss of muscle mass that can exceed 10% over the 1st week, which leads to functional impairment and complications post-hospital discharge. Physical therapy and in-hospital mobility program may reduce the incident of hospital-acquired weakness, but they are often impractical for COVID-19 patients. In particular, conventional mobility programs are challenging for those who are being treated in an intensive Care Unit. The purpose of this study is to test feasibility and proof-of-concept effectiveness of daily use of lower extremity electrical stimulation (EE) therapy, as a practical solution to address lower extremity muscle deconditioning, to address chronic consequences of COVID-19 including hospital-acquired weakness.

Phase I:

The purpose of this study is to test feasibility and proof-of-concept effectiveness of lower extremity electrical stimulation (EE) therapy to prevent muscular complications of COVID-19 including hospital-acquired weakness and neuropathy. This is a proof of concept randomized control trial (RCT) study for prevention. Eligible participants (n=19 anticipated) will be recruited from the Baylor St. Luke's' Medical Center (Houston, Texas). To be eligible participants should be hospitalized because of COVID-19 infection and suspected to be at risk for hospital acquired-weakness based on judgment of clinical intensivist investigators. Participants will be excluded if they are paralyzed. Other exclusion criteria include blow the knee amputation, those who have a demand-type cardiac pacemaker, implanted defibrillator or other implanted electronic device; those with wound infection, and other conditions that may interfere with outcomes or increase the risk of the use EE based on judgement of clinicians.

The Investigators hypothesize that implementation of EE as means of regular activation of lower extremity muscle is feasible and acceptable for the target population and would help to retain lower extremity muscle mass, lower extremity tissue oxygen saturation and perfusion, and thus reducing the severity of hospital acquired weakness and potentially improve outcomes of treatment among COVID-19 patients.

Participants will be randomized to intervention (IG) or control group (CG)). The entire cohort will receive daily EE in lower extremity (e.g. Gastronemius, tibial anterior muscle) up to 1 hour. EE therapy will be provided using a bio-electric stimulation technology (BEST) platform (Tennant Biomodulator PRO®, AVAZZIA, Inc.). The EE device will be functional for IG and non-functional for CG. The primary outcomes include between group difference and change from the baseline in muscle endurance, muscle strength, lower extremity tissue oxygen saturation, neuropathy, and muscle atrophy. Outcomes will be assessed at baseline, time of discharge or 2 weeks, whichever comes first.

Inclusion Criteria:

• COVID-19 test positive critically ill patients in need of assisted ventilation requiring care in the intensive care unit
• COVID-19 test positive critically ill patients in need of assisted ventilation requiring prolonged care in the hospital

Exclusion Criteria:

• Paralyzed patients (i.e., rocuronium, cisatracurium) at the moment of enrollment
• Patients under vasopressor therapy (i.e., norepinephrine, epinephrine, vasopressin) at the moment of enrollment
• Patients expected to be discharged in the next 24 hours
• Patient has a demand-type cardiac pacemaker, implanted defibrillator or other implanted electronic device.
• Active wound infection
• Below the knee amputations
• Based on the clinicians decision whether the patient is eligible for the study

an average of 2 weeks(phase I)

Serious adverse events related to electrical stimulation therapy (e.g. pain, muscle damage, skin irritation) will be collected during the study.

Devices may be active or sham.