Inclusion Criteria:  18 to 40 years of age Healthy, free of known cardiovascular, metabolic, or musculoskeletal disease  Exclusion Criteria:  History of smoking (within 3 months), diagnosed cardiovascular or metabolic disease, recent musculoskeletal injury preventing handgrip exercise, prescription of chronic medications other than oral contraceptives. Current or recent (within 6 months) use of ketone ester supplementation or participation in a ketogenic diet. Inability to abstain from drugs, caffeine, alcohol, or strenuous physical activity prior to the study visit.