This study will test whether pharmacologic agents that may improve mitochondrial function and
energy fuel metabolism [Empagliflozin (Empa)], with and without additional supplements that
increase perfusion and fatty acid oxidation [Potassium Nitrate (KNO3)], improve submaximal
exercise endurance and skeletal muscle oxidative phosphorylation capacity (SkM OxPhos) in
participants with Heart Failure with Preserved Ejection Fraction (HFpEF).