Inclusion Criteria:  BMI<40, 1-4 weeks post active COVID19 infection physician approval for undertaking exercise testing and training. Adequate intracranial ultrasound windows  Exclusion Criteria:  Lingering COVID19 symptomology cardiovascular disease pulmonary disease cerebrovascular disease taking medication that influences heart rate, blood pressure, or cerebrovascular function, severe obesity (BMI >40) metabolic comorbidities (diabetes, metabolic syndrome), recently been diagnosed with a mild traumatic brain injury (within past 6 months).