REmotely Monitored, Mobile Health Supported Multidomain Rehabilitation Program With High Intensity Interval Training for COVID-19

Inclusion Criteria:

* Primary diagnosis of COVID-19 requiring hospital admission
* Discharged or expected to be discharged directly home from the hospital (not to a skilled nursing facility, inpatient rehabilitation center, or long-term acute care hospital)
* Able to ambulate with or without a gait aid prior to hospital discharge
* Age ≥ 18 years

Exclusion Criteria:

* Hospital discharge \> 60 days unless readmitted to hospital in first 30 days, then 60 day window restarts and new exclusion is last hospital discharge \> 60 days
* Not ambulating independently prior to COVID-19 illness (use of a gait aid permitted)
* Functional impairment resulting in inability to exercise at baseline
* Inability or unwillingness to comply with the study requirements or unable or unwilling to follow coaching via mobile-health iPhone interaction
* Any absolute contraindications to exercise, including but not limited to:

  * Recent (\< 5 days) acute primary cardiac event
  * Unstable Angina
  * Uncontrolled dysrhythmias causing symptoms or hemodynamic compromise
  * Uncontrolled hypertension over 255 mmHg Systolic or 155 diastolic blood pressure
  * Symptomatic aortic stenosis
  * Uncontrolled symptomatic heart failure
  * Acute myocarditis or pericarditis
  * Suspected or known dissecting aneurysm
* Any adverse changes during GXT (i.e., persistent oxygen saturation drop below 88% while on prescribed oxygen therapy or significant hypotension such as mean arterial blood pressure \< 60 mmHg on 2 consecutive readings within 1 minute)
* High risk for non-adherence as determined by screening evaluation
* Any condition, including cognitive impairment, that, in the judgment of the investigator, precludes participation because it could affect subject safety or ability of subject to complete the study
* Pregnant