Inclusion Criteria:

Healthy Adults

• Healthy participants (≥ 18 years of age) will be recruited from the surrounding community.
• These participants will not have a history of cardiovascular, pulmonary, neurologic, orthopedic, or other diseases affecting the neuromuscular system.
• Additional inclusion criteria include: age, sex, and body mass index matched to the Human Hypertension (HTN) group and those who are able to engage in exercise (i.e., without significant orthopedic limitations or musculoskeletal disorders limiting their ability to exercise).

Patients with Hypertension

•  ≥ 18 years of age.
• Patients with HTN will have a clinical diagnosis of essential HTN and receiving standard pharmacologic therapy for > 3 months.
• In addition to their primary care physician, Dr. Borlaug, M.D. will provide oversight for all participants throughout the study duration. Patients will be tested while receiving optimized standard pharmacologic optimized therapy. All patients will be managed by their primary care physician or cardiologist with additional review by Dr. Borlaug (Co-Investigator) prior to enrollment to ensure inclusion and exclusion criteria have been satisfied and participation in exercise testing is safe. Additional inclusion criteria include no history of cardiovascular (except for HTN), pulmonary, renal, and/or muscular related abnormalities and those who are able to engage in exercise (i.e., without significant orthopedic limitations or musculoskeletal disorders limiting their ability to exercise).

Patients with Heart Failure:

• Patients with HF with reduced ejection fraction and HF with preserved ejection fraction. Patients with HF are expected to have a history of ischemic or idiopathic dilated cardiomyopathy (stable > 6 months with a duration of > 1 year) and New York Heart Association class I-III. Although HF medications may influence multiple physiologic systems, we feel it is important, practical, and safe to study these patients under conditions of optimal care. Concurrent withdrawal of ACE-inhibitor, beta-blocker, digoxin, and/or diuretic therapies would likely be associated with moderate decompensation in a high proportion of patients. All patients will be managed by their primary care physician or cardiologist prior to enrollment to ensure inclusion and exclusion criteria have been satisfied and participation in exercise testing is safe.

Exclusion Criteria:

• ≥ 18 years of age.
• History of dangerous arrhythmias.
• Body mass index > 35 kg/m^2.
• Current smokers and/or smoking history > 15 pack years.
• Pregnant women (testing will be done by research team if requested).
• Uremia, history of allergy to iodides.
• Impaired renal function.
• Creatinine value greater than or equal to 1.3 mg/dL (via clinical record within the past 6 months).
• Diagnosis of liver disease; or (10) individuals who are not able to engage in exercise.
• For individuals agreeing to undergo dual energy x-ray absorptiometry (DEXA) scanning for measurement of body composition as part of their study visit, additional exclusion criteria apply: recently administered gastrointestinal contrast or radionuclides; severe degenerative changes or fracture deformity in measurement areas; or inability to attain correct position and/or remain motionless for the measurement period.

Eligibility last updated 7/26/22. Questions regarding updates should be directed to the study team contact.