Nitrite Supplementation in Long COVID Patients

Potential benefits of a nitrate juice supplement to improve skeletal muscle function and associated physical capacity will be studied in patients with Long COVID. Consenting patients with Long-COVID will be randomized to receive Beet-It nitrate beverage group versus a nitrate-depleted placebo beverage. Both groups will receive physical therapy at the long COVID Clinic at VAPHS with therapeutic goals to improve strength, balance, inspiratory, and aerobic capabilities. Physical therapy will last for 2 weeks and include 2 or 3 sessions with a physical therapist a week depending on each individual's exercise tolerance. These sessions can take place on-site or at home (or a hybrid combination) All participants will undergo functional assessments and tissue assessments before and after the 14-day study intervention.

Inclusion Criteria:Veterans with prior COVID-19, with residual symptoms of long COVID including increased fatigability (i.e., RPE 10 during steady-state walking and reduced physical activity (<8 Mets/day)).Inclusion limited to age 18 and overExclusion Criteria:Blood pressure <110/60 mmHg, either systolic or diastolic valueUnable to hold warfarin, novel oral anticoagulants (NOACs) or aspirin for 3 days prior to muscle biopsy, or to hold thienopyridine medications for 5 days prior to muscle biopsyCurrent use of organic nitrates or phosphodiesterase type 5 (PDE5) inhibitorsOrthopedic or other chronic condition which limits physical activity or functional testing assessmentsEnd-stage diseaseDementia or other reason unable to give informed consentAnemia (hemoglobin <11.0 g/dL or <10.0 g/dL)Unstable psychiatric diagnosisClinically significant alcohol intake (CAGE score 2 or >) or substance abuseChronic use of oral corticosteroids or medications that affect muscle functionUse of anti-bacterial mouthwash or antacids that confound the nitrate/nitrite/NO pathway.Involved in another greater than minimal risk study