REmotely monitored, Mobile health-supported Multidomain Rehabilitation with High Intensity Interval Training for COVID-19 (REMM-HIIT-CoV): Trial Design and Rationale.

IMPORTANCE: Individuals hospitalized with COVID-19 are at increased risk for prolonged physical, cognitive, and psychosocial impairments. Timely post-acute rehabilitation may reduce these sequelae and accelerate recovery. OBJECTIVE: The objective is to determine whether a REmotely monitored, Mobile health-supported Multidomain Rehabilitation Program incorporating High-intensity Interval Training (REMM-HIIT-CoV) after COVID-19 hospitalization improves functional exercise capacity. DESIGN: This study is a multicenter, single-blinded, attention controlled, prospective randomized controlled trial. SETTING: Five academic medical centers will enroll participants for remotely delivered and monitored rehabilitation. PARTICIPANTS: The study will enroll 140 community-dwelling adults discharged within 60 days of COVID-19 hospitalization. INTERVENTION: Participants are randomized to either (1) a 12-week, individually tailored, structured and progressive multidomain physical rehabilitation intervention-targeting deficits in balance, mobility, strength, and endurance-delivered via videoconference and remotely monitored using activity trackers and a mobile health application; or (2) an exercise education control group without individualized exercise prescription. MAIN OUTCOMES AND MEASURES: The primary outcome is functional exercise capacity, measured by 6-minute walk distance at 3 months post-randomization. Secondary outcomes include cardiorespiratory fitness (VO2peak), physical function (Short Physical Performance Battery, 30-second Sit-to-Stand, Grip Strength), frailty (Fried Frailty Index), and cognitive function (Montreal Cognitive Assessment), self-reported quality of life (EQ-5D-5L), functional status (Duke Activity Status Index, Lawton Instrumental Activities of Daily Living), mental health (Hospital Anxiety and Depression Scale), and health-related social needs (Accountable Health Communities Health-related Social Needs Screening Tool). Exploratory outcomes include blood-derived biomarkers of inflammation and mitochondrial function, and ultrasound measures of lower extremity skeletal muscle structure. CONCLUSIONS: REMM-HIIT-CoV is the first randomized trial to evaluate a remotely delivered, structured, and tailored multidomain rehabilitation program incorporating HIIT in post-hospitalized COVID-19 survivors. RELEVANCE: Findings may inform evidence-based guidelines and policy-relevant models for home-based remote rehabilitation after severe respiratory infections.