Respiratory Muscle-mediated Neural and Cardiovascular Consequences in Heart Failure With Preserved Ejection Fraction

The participants enrolled in this study will be asked to make 4 or 9 separate study visits. Healthy participants will perform 4 study visits and heart failure participants will perform 9 study visits.

During study visit 1, the participants will be asked to get a DEXA bone scan, perform pulmonary function tests, and exercise on a stationary bike at maximal exertion while breathing into a mouth piece. During the exercise test, a iodine-based dye will be injected via a venous catheter in the arm. Also, a thin balloon will be inserted through the nose into the esophagus.

During study visit 2, the participants will breathe the same way they did during exercise, but will be seated and not exercising. A thin balloon will be inserted through the nose into the esophagus.

During study visits 3 and 4, the participants will perform different respiratory muscle workouts at rest that will be at different intensities ranging from very easy to moderate for ~10 minutes. An iodine-based dye will be injected via a venous catheter in the arm.

The participant's with heart failure will then perform 8 weeks of breathing muscle training at home. After 3 weeks of breathing muscle training, the participants will return for study visit 5 where the training load will be adjusted. Following the 8 weeks of breathing muscle training, the heart failure participants will perform the same 4 study visits as outlined above.